Sample records for litter environment affects

  1. Fallout volume and litter type affect 137Cs concentration difference in litter between forest and stream environments.

    PubMed

    Sakai, Masaru; Gomi, Takashi; Negishi, Junjiro N

    2016-11-01

    It is important to understand the changes in the 137 Cs concentration in litter through leaching when considering that 137 Cs is transferred from basal food resources to animals in forested streams. We found that the difference of 137 Cs activity concentration in litter between forest and stream was associated with both litter type and 137 Cs fallout volume around Fukushima, Japan. The 137 Cs activity concentrations in the litter of evergreen conifers tended to be greater than those in the litter of broad-leaved deciduous trees because of the absence of deciduous leaves during the fallout period in March 2011. Moreover, 137 Cs activity concentrations in forest litter were greater with respect to the 137 Cs fallout volume. The 137 Cs activity concentrations in stream litter were much lower than those in forest litter when those in forest litter were higher. The 137 Cs leaching patterns indicated that the differences in 137 Cs activity concentration between forest and stream litter could change with changes in both fallout volume and litter type. Because litter is an important basal food resource in the food webs of both forests and streams, the 137 Cs concentration gradient reflects to possible 137 Cs transfer from lower to higher trophic animals. Our findings will improve our understanding of the spatial heterogeneity and variability of 137 Cs concentrations in animals resident to the contaminated landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. [Litter decomposition and its main affecting factors in tidal marshes of Minjiang River Estuary, East China].

    PubMed

    Zhang, Lin-Hai; Zeng, Cong-Sheng; Zhang, Wen-Juan; Wang, Tian-E; Tong, Chuan

    2012-09-01

    By using litterbag method, this paper studied the decomposition of the leaf- and flower litters of two emergent macrophytes, native species Phragmites australis and invasive species Spartina alterniflora, and related affecting factors in the Minjiang River estuary of East China. In the decomposition process of the litters, the decay of standing litter (0-90 days) was an important period, and the loss rate of the flower- and leaf litters dry mass of P. australis and S. alterniflora was 15.0 +/- 3.5% and 13.3 +/- 1.1%, and 31.9 +/- 1.1% and 20.8 +/- 1.4%, respectively. During lodging decay period (91-210 days), the loss rate of the flower- and leaf litters dry mass of P. australis and S. alterniflora was 69.5 +/- 0.6% and 71.5 +/- 2.5%, and 76.8 +/- 1.9% and 67.5 +/- 2.1%, respectively. In standing decay period, the decomposition rate of the two plants litters was positively correlated with the litters C/N but negatively correlated to the litters N/P, and the litters P was an important factor limiting the litters decay. In lodging decay period, the effects of the litters C/N, C/P, and N/P decreased, while the environment factors (climate, soil moisture, soil acidity and salinity, and sediment properties) acted more important roles. The differences in the factors affecting the decay of the litters in different decomposition periods were mainly related to the micro-environment and tidal process for the two plant communities.

  3. Optimizing temperament through litter size in short-lived, iteroparous mammals in seasonal environments.

    PubMed

    Eccard, Jana A; Rödel, Heiko G

    2011-09-01

    A number of short-lived, iteroparous animal species have small broods in the early breeding season and larger broods in later breeding season. Brood size affects not only offspring size, but as recent results suggest, may also affect offspring's temperament, hormonal status, and aggression as adults. Most populations of short-lived, iteroparous mammals fluctuate predictably over the season, with low densities in winter, increasing densities in summer and a population peak in late summer followed by a population breakdown. If animals live only through parts of the season, possibly such differences in density and hence also in social environments among seasons require different personality types to increase individual fitness. We present data on behavior of European rabbits from a field enclosure study. These data clearly show that aggressiveness is higher in young from smaller litters than in young from larger litters, and smaller litters are usually born during the early breeding season. Moreover, our data suggest that behavioral types of the young rabbits are stable over time, at least during their subadult life. We suggest, that changes in mean litter size over the course of the breeding season may not only be a product of mothers' age or food availability, but may also have an adaptive function by preparing offspring characteristics for adulthood in a social environment undergoing predictable density changes within the season. Copyright © 2011 Wiley Periodicals, Inc.

  4. Intestinal Microbiota of Broiler Chickens As Affected by Litter Management Regimens

    PubMed Central

    Wang, Lingling; Lilburn, Mike; Yu, Zhongtang

    2016-01-01

    Poultry litter is a mixture of bedding materials and enteric bacteria excreted by chickens, and it is typically reused for multiple growth cycles in commercial broiler production. Thus, bacteria can be transmitted from one growth cycle to the next via litter. However, it remains poorly understood how litter reuse affects development and composition of chicken gut microbiota. In this study, the effect of litter reuse on the microbiota in litter and in chicken gut was investigated using 2 litter management regimens: fresh vs. reused litter. Samples of ileal mucosa and cecal digesta were collected from young chicks (10 days of age) and mature birds (35 days of age). Based on analysis using DGGE and pyrosequencing of bacterial 16S rRNA gene amplicons, the microbiota of both the ileal mucosa and the cecal contents was affected by both litter management regimen and age of birds. Faecalibacterium, Oscillospira, Butyricicoccus, and one unclassified candidate genus closely related to Ruminococcus were most predominant in the cecal samples, while Lactobacillus was predominant in the ileal samples at both ages and in the cecal samples collected at day 10. At days 10 and 35, 8 and 3 genera, respectively, in the cecal luminal microbiota differed significantly in relative abundance between the 2 litter management regimens. Compared to the fresh litter, reused litter increased predominance of halotolerant/alkaliphilic bacteria and Faecalibacterium prausnitzii, a butyrate-producing gut bacterium. This study suggests that litter management regimens affect the chicken GI microbiota, which may impact the host nutritional status and intestinal health. PMID:27242676

  5. Increasing shrub abundance and N addition in Arctic tundra affect leaf and root litter decomposition differently

    NASA Astrophysics Data System (ADS)

    McLaren, J.; van de Weg, M. J.; Shaver, G. R.; Gough, L.

    2013-12-01

    Changes in global climate have resulted in a ';greening' of the Arctic as the abundance of deciduous shrub species increases. Consequently, not only the living plant community, but also the litter composition changes, which in turn can affect carbon turnover patterns in the Arctic. We examined effects of changing litter composition (both root and leaf litter) on decomposition rates with a litter bag study, and specifically focused on the impact of deciduous shrub Betula nana litter on litter decomposition from two evergreen shrubs (Ledum palustre, and Vaccinium vitis-idaea) and one graminoid (Eriophorum vaginatum) species. Additionally, we investigated how decomposition was affected by nutrient availability by placing the litterbags in an ambient and a fertilized moist acidic tundra environment. Measurements were carried out seasonally over 2 years (after snow melt, mid-growing season, end growing season). We measured litter mass loss over time, as well as the respiration rates (standardized for temperature and moisture) and temperature sensitivity of litter respiration at the time of harvesting the litter bags. For leaves, Betula litter decomposed faster than the other three species, with Eriophorum leaves decomposing the slowest. This pattern was observed for both mass loss and litter respiration rates, although the differences in respiration became smaller over time. Surprisingly, combining Betula with any other species resulted in slower overall weight loss rates than would be predicted based on monoculture weight loss rates. This contrasted with litter respiration at the time of sampling, which showed a positive mixing effect of adding Betula leaf liter to the other species. Apparently, during the first winter months (September - May) Betula litter decomposition is negatively affected by mixing the species and this legacy can still be observed in the total mass loss results later in the year. For root litter there were fewer effects of species identity on root

  6. 17β-estradiol in runoff as affected by various poultry litter application strategies.

    PubMed

    Delaune, P B; Moore, P A

    2013-02-01

    Steroidal hormones, which are excreted by all mammalian species, have received increasing attention in recent years due to potential environmental implications. The objective of this study was to evaluate 17β-estradiol concentrations in runoff water from plots receiving poultry litter applications using various management strategies. Treatments included the effects of 1) aluminum sulfate (alum) application rates to poultry litter; 2) time until the first runoff event occurs after poultry litter application; 3) poultry litter application rate; 4) fertilizer type; and 5) litter from birds fed modified diets. Rainfall simulators were used to cause continuous runoff from fertilized plots. Runoff samples were collected and analyzed for 17β-estradiol concentrations. Results showed that increasing alum additions to poultry litter decreased 17β-estradiol concentrations in runoff water. A significant exponential decline in 17β-estradiol runoff was also observed with increasing time until the first runoff event after litter application. Concentrations of 17β-estradiol in runoff water increased with increasing litter application rate and remained above background concentrations after three runoff events at higher application rates. Management practices such as diet modification and selection of fertilizer type were also shown to affect 17β-estradiol concentrations in runoff water. Although results from these experiments typically represented a worst case scenario since runoff events generally occurred immediately after litter application, the contaminant loss from pastures fertilized with poultry litter can be expected to be much lower than continual estradiol loadings observed from waste water treatment plants. Management practices such as alum amendment and application timing can significantly reduce the risk of 17β-estradiol losses in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Ambient temperature affects postnatal litter size reduction in golden hamsters.

    PubMed

    Ohrnberger, Sarah A; Monclús, Raquel; Rödel, Heiko G; Valencak, Teresa G

    2016-01-01

    To better understand how different ambient temperatures during lactation affect survival of young, we studied patterns of losses of pups in golden hamsters ( Mesocricetus auratus ) at different ambient temperatures in the laboratory, mimicking temperature conditions in natural habitats. Golden hamsters produce large litters of more than 10 young but are also known to wean fewer pups at the end of lactation than they give birth to. We wanted to know whether temperature affects litter size reductions and whether the underlying causes of pup loss were related to maternal food (gross energy) intake and reproductive performance, such as litter growth. For that, we exposed lactating females to three different ambient temperatures and investigated associations with losses of offspring between birth and weaning. Overall, around one third of pups per litter disappeared, obviously consumed by the mother. Such litter size reductions were greatest at 30 °C, in particular during the intermediate postnatal period around peak lactation. Furthermore, litter size reductions were generally higher in larger litters. Maternal gross energy intake was highest at 5 °C suggesting that mothers were not limited by milk production and might have been able to raise a higher number of pups until weaning. This was further supported by the fact that the daily increases in litter mass as well as in the individual pup body masses, a proxy of mother's lactational performance, were lower at higher ambient temperatures. We suggest that ambient temperatures around the thermoneutral zone and beyond are preventing golden hamster females from producing milk at sufficient rates. Around two thirds of the pups per litter disappeared at high temperature conditions, and their early growth rates were significantly lower than at lower ambient temperatures. It is possible that these losses are due to an intrinsic physiological limitation (imposed by heat dissipation) compromising maternal energy intake and

  8. Poultry litter and the environment: Physiochemical properties of litter and soil during successive flock rotations and after remote site deposition.

    PubMed

    Crippen, Tawni L; Sheffield, Cynthia L; Byrd, J Allen; Esquivel, Jesus F; Beier, Ross C; Yeater, Kathleen

    2016-05-15

    The U.S. broiler meat market has grown over the past 16 years and destinations for U.S. broiler meat exports expanded to over 150 countries. This market opportunity has spurred a corresponding increase in industrialized poultry production, which due to the confined space in which high numbers of animals are housed, risks accumulating nutrients and pollutants. The purpose of this research was to determine the level of pollutants within poultry litter and the underlying soil within a production facility; and to explore the impact of spent litter deposition into the environment. The study follows a production facility for the first 2.5 years of production. It monitors the effects of successive flocks and management practices on 15 physiochemical parameters: Ca, Cu, electrical conductivity, Fe, K, Mg, Mn, moisture, Na, NO3(-)/N, organic matter, P, pH, S, and Zn. Litter samples were collected in-house, after clean-outs and during stockpiling. The soil before house placement, after the clean-outs and following litter stockpiling was monitored. Management practices markedly altered the physiochemical profiles of the litter in-house. A canonical discriminant analysis was used to describe the relationship between the parameters and sampling times. The litter profiles grouped into five clusters corresponding to time and management practices. The soil in-house exhibited mean increases in all physiochemical parameters (2-297 fold) except Fe, Mg, %M, and pH. The spent litter was followed after deposition onto a field for use as fertilizer. After 20 weeks, the soil beneath the litter exhibited increases in EC, Cu, K, Na, NO3(-)/N, %OM, P, S and Zn; while %M decreased. Understanding the impacts of industrialized poultry farms on the environment is vital as the cumulative ecological impact of this land usage could be substantial if not properly managed to reduce the risk of potential pollutant infiltration into the environment. Published by Elsevier B.V.

  9. Genetic by environment interactions affect plant–soil linkages

    PubMed Central

    Pregitzer, Clara C; Bailey, Joseph K; Schweitzer, Jennifer A

    2013-01-01

    The role of plant intraspecific variation in plant–soil linkages is poorly understood, especially in the context of natural environmental variation, but has important implications in evolutionary ecology. We utilized three 18- to 21-year-old common gardens across an elevational gradient, planted with replicates of five Populus angustifolia genotypes each, to address the hypothesis that tree genotype (G), environment (E), and G × E interactions would affect soil carbon and nitrogen dynamics beneath individual trees. We found that soil nitrogen and carbon varied by over 50% and 62%, respectively, across all common garden environments. We found that plant leaf litter (but not root) traits vary by genotype and environment while soil nutrient pools demonstrated genotype, environment, and sometimes G × E interactions, while process rates (net N mineralization and net nitrification) demonstrated G × E interactions. Plasticity in tree growth and litter chemistry was significantly related to the variation in soil nutrient pools and processes across environments, reflecting tight plant–soil linkages. These data overall suggest that plant genetic variation can have differential affects on carbon storage and nitrogen cycling, with implications for understanding the role of genetic variation in plant–soil feedback as well as management plans for conservation and restoration of forest habitats with a changing climate. PMID:23919173

  10. Do soil organisms affect aboveground litter decomposition in the semiarid Patagonian steppe, Argentina?

    PubMed

    Araujo, Patricia I; Yahdjian, Laura; Austin, Amy T

    2012-01-01

    Surface litter decomposition in arid and semiarid ecosystems is often faster than predicted by climatic parameters such as annual precipitation or evapotranspiration, or based on standard indices of litter quality such as lignin or nitrogen concentrations. Abiotic photodegradation has been demonstrated to be an important factor controlling aboveground litter decomposition in aridland ecosystems, but soil fauna, particularly macrofauna such as termites and ants, have also been identified as key players affecting litter mass loss in warm deserts. Our objective was to quantify the importance of soil organisms on surface litter decomposition in the Patagonian steppe in the absence of photodegradative effects, to establish the relative importance of soil organisms on rates of mass loss and nitrogen release. We estimated the relative contribution of soil fauna and microbes to litter decomposition of a dominant grass using litterboxes with variable mesh sizes that excluded groups of soil fauna based on size class (10, 2, and 0.01 mm), which were placed beneath shrub canopies. We also employed chemical repellents (naphthalene and fungicide). The exclusion of macro- and mesofauna had no effect on litter mass loss over 3 years (P = 0.36), as litter decomposition was similar in all soil fauna exclusions and naphthalene-treated litter. In contrast, reduction of fungal activity significantly inhibited litter decomposition (P < 0.001). Although soil fauna have been mentioned as a key control of litter decomposition in warm deserts, biogeographic legacies and temperature limitation may constrain the importance of these organisms in temperate aridlands, particularly in the southern hemisphere.

  11. Litter composition effects on decomposition across the litter-soil interface

    EPA Science Inventory

    Background/Question/Methods Many studies have investigated the influence of plant litter species composition on decomposition dynamics, but given the variety of communities and environments around the world, a variety of consequences of litter-mixing have been reported. Litter ...

  12. Eutrophication triggers contrasting multilevel feedbacks on litter accumulation and decomposition in fens.

    PubMed

    Emsens, W-J; Aggenbach, C J S; Grootjans, A P; Nfor, E E; Schoelynck, J; Struyf, E; van Diggelen, R

    2016-10-01

    Eutrophication is a major threat for the persistence of nutrient-poor fens, as multilevel feedbacks on decomposition rates could trigger carbon loss and increase nutrient cycling. Here, we experimentally investigate the effects of macronutrient (NPK) enrichment on litter quality of six species of sedge (Carex sp.), which we relate to litter decomposition rates in a nutrient-poor and nutrient-rich environment. Our research focused on four levels: we examined how eutrophication alters (1) fresh litter production ("productivity shift"), (2) litter stoichiometry within the same species ("intraspecific shift"), (3) overall litter stoichiometry of the vegetation under the prediction that low-competitive species are outcompeted by fast-growing competitors ("interspecific shift"), and (4) litter decomposition rates due to an altered external environment (e.g., shifts in microbial activity; "exogenous shift"). Eutrophication triggered a strong increase in fresh litter production. Moreover, individuals of the same species produced litter with lower C:N and C:P ratios, higher K contents, and lower lignin, Ca and Mg contents (intraspecific shift), which increased litter decomposability. In addition, species typical for eutrophic conditions produced more easily degradable litter than did species typical for nutrient-poor conditions (interspecific shift). However, the effects of nutrient loading of the external environment (exogenous shift) were contradictory. Here, interactions between litter type and ambient nutrient level indicate that the (exogenous) effects of eutrophication on litter decomposition rates are strongly dependent of litter quality. Moreover, parameters of litter quality only correlated with decomposition rates for litter incubated in nutrient-poor environments, but not in eutrophic environments. This suggests that rates of litter decomposition can be uncoupled from litter stoichiometry under eutrophic conditions. In conclusion, our results show that

  13. Litter sex composition affects life-history traits in yellow-bellied marmots.

    PubMed

    Monclús, Raquel; Blumstein, Daniel T

    2012-01-01

    1. The presence of siblings might have long-lasting fitness consequences because they influence the early environment in which an animal develops. Several studies under laboratory conditions have shown long-lasting consequences from the presence of male siblings in utero on morphology and life-history traits. However, in wild animals, such effects of litter sex composition are unexplored. 2. We capitalized on a long-term study of individually marked yellow-bellied marmots (Marmota flaviventris) and documented the effects of weaned litter sex composition and anogenital distance on several life-history and fitness traits. 3. First, we demonstrated that the number of males in a litter influenced anogenital distance. Then, we found that masculinized females, those with larger anogenital distances, were less likely to survive their first hibernation, were more likely to disperse and were less likely to become pregnant and wean young. Males from male-biased litters had lower growth rates, but we failed to detect longer-term consequences. 4. Taken together, our results show profound sex-dependent effects of litter sex composition, probably due to differential prenatal exposure to androgens, in free-living animals. We conclude that masculinization might constitute an alternative mechanism explaining variation in different demographic traits. This finding highlights the importance of studying these maternal effects, and they enhance our concern over the widespread use of endocrine disrupting compounds. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

  14. Litter type affects the activity of aerobic decomposers in a boreal peatland more than site nutrient and water table regimes

    NASA Astrophysics Data System (ADS)

    Straková, P.; Niemi, R. M.; Freeman, C.; Peltoniemi, K.; Toberman, H.; Heiskanen, I.; Fritze, H.; Laiho, R.

    2011-09-01

    acquisition. This caused an increase in the rate of litter decomposition. The effects of the short-term WT drawdown were minor compared to those of the long-term WT drawdown: e.g., the increase in the activity of C-acquiring enzymes was up to 120 % (bog) or 320 % (fen) higher after the long-term WT drawdown compared to the short-term WT drawdown. In general, the patterns of microbial activity as well as their responses to WT drawdown depended on peatland type: e.g., the shift in activity allocation to C-acquisition was up to 100 % stronger at the fen compared to the bog. Our results imply that changes in plant community composition in response to persistent WT drawdown will strongly affect the C dynamics of peatlands. The predictions of decomposer activity under changing climate and/or land-use thus cannot be based on the direct effects of the changed environment only, but need to consider the indirect effects of environmental changes: the changes in plant community composition, their dependence on peatland type, and their time scale.

  15. Litter decay controlled by temperature, not soil properties, affecting future soil carbon.

    PubMed

    Gregorich, Edward G; Janzen, Henry; Ellert, Benjamin H; Helgason, Bobbi L; Qian, Budong; Zebarth, Bernie J; Angers, Denis A; Beyaert, Ronald P; Drury, Craig F; Duguid, Scott D; May, William E; McConkey, Brian G; Dyck, Miles F

    2017-04-01

    Widespread global changes, including rising atmospheric CO 2 concentrations, climate warming and loss of biodiversity, are predicted for this century; all of these will affect terrestrial ecosystem processes like plant litter decomposition. Conversely, increased plant litter decomposition can have potential carbon-cycle feedbacks on atmospheric CO 2 levels, climate warming and biodiversity. But predicting litter decomposition is difficult because of many interacting factors related to the chemical, physical and biological properties of soil, as well as to climate and agricultural management practices. We applied 13 C-labelled plant litter to soil at ten sites spanning a 3500-km transect across the agricultural regions of Canada and measured its decomposition over five years. Despite large differences in soil type and climatic conditions, we found that the kinetics of litter decomposition were similar once the effect of temperature had been removed, indicating no measurable effect of soil properties. A two-pool exponential decay model expressing undecomposed carbon simply as a function of thermal time accurately described kinetics of decomposition. (R 2  = 0.94; RMSE = 0.0508). Soil properties such as texture, cation exchange capacity, pH and moisture, although very different among sites, had minimal discernible influence on decomposition kinetics. Using this kinetic model under different climate change scenarios, we projected that the time required to decompose 50% of the litter (i.e. the labile fractions) would be reduced by 1-4 months, whereas time required to decompose 90% of the litter (including recalcitrant fractions) would be reduced by 1 year in cooler sites to as much as 2 years in warmer sites. These findings confirm quantitatively the sensitivity of litter decomposition to temperature increases and demonstrate how climate change may constrain future soil carbon storage, an effect apparently not influenced by soil properties. © 2016 Her Majesty

  16. Changes in litter quality induced by nutrient addition alter litter decomposition in an alpine meadow on the Qinghai-Tibet Plateau

    PubMed Central

    Zhu, Wenyan; Wang, Jinzhou; Zhang, Zhenhua; Ren, Fei; Chen, Litong; He, Jin-Sheng

    2016-01-01

    The effects of nitrogen (N) and phosphorus (P) addition on litter decomposition are poorly understood in Tibetan alpine meadows. Leaf litter was collected from plots within a factorial N × P addition experiment and allowed to decompose over 708 days in an unfertilized plot to determine the effects of N and/or P addition on litter decomposition. Results showed that nutrient addition significantly affected initial P and P-related biochemical properties of litter from all four species. However, the responses of litter N and N-related biochemical properties to nutrient addition were quite species-specific. Litter C decomposition and N release were species-specific. However, N and P addition significantly affected litter P release. Ratios of Hemicellulose + Cellulose to N and P were significantly related to litter C decomposition; C:N ratio was a determinant of litter N release; and C:P and (Hemicellulose + Cellulose):P controlled litter P release. Overall, litter C decomposition was controlled by litter quality of different plant species, and strongly affected by P addition. Increasing N availability is likely to affect litter C decomposition more indirectly by shifting plant species composition than directly by improving litter quality, and may accelerate N and P cycles, but shift the ecosystem to P limitation. PMID:27694948

  17. Potential Re-utilization of Composted Mangrove Litters for Pond Environment Quality Improvement

    NASA Astrophysics Data System (ADS)

    Dwi Hastuti, Endah; Budi Hastuti, Rini; Hariyati, Riche

    2018-05-01

    Production of mangrove litter from pruning and thinning activities is potential source of organic materials which could be re-utilized to improve pond environment quality and fertility. This research aimed to analyze the nutrient composition compost produced from mangrove litter and to describe the effect of compost application on pond quality. This research was conducted through two phases, including composting trial and application of compost on pond trial. Composting process was conducted for 45-60 days on mangrove litter achieved from pruning activities in the silvofishery pond using composting container, while application of compost in pond was conducted by pouring 2 kg of compost in 25 m2 pond. Production of compost included solid compost and liquid compost. Nutrient concentration of solid compost was ranged from 0.47-0.52% for N; 0.36-0.44% for P; and 5.45-6.39% for organic C, while liquid compost provided 0.62-0.69%; 0.24-0.32%; and 3.98-4.45% respectively for N, P and organic C. While C/N ratio was ranged from 11.60-12.78 and 5.77-7.18 respectively for solid and liquid compost. Solid compost quality resulted that N, P and C/N ration had fulfilled the standart criteria defined by Indonesia National Standart for compost. Observed impact of compost application on pond water quality were the improvement of water clarity and increasing abundance of klekap (lab-lab). This showed that mangrove litters could be converted into a more productive materials to enhance pond environment quality and productivity, decrease management cost and increase benefit. Scheduled fertilization with compost is suggested to be conducted to provide best benefit on silvofishery management.

  18. Sustaining anti-littering behavior within coastal and marine environments: Through the macro-micro level lenses.

    PubMed

    Beeharry, Yashna Devi; Bekaroo, Girish; Bokhoree, Chandradeo; Phillips, Michael Robert; Jory, Neelakshi

    2017-06-30

    Being regarded as a problem of global dimensions, marine litter has been a growing concern that affects human beings, wildlife and the economic health of coastal communities to varying degrees. Due to its involvement with human behavior, marine littering has been regarded as a cultural matter encompassing macro and micro level aspects. At the micro or individual level, behavior and behavioral motivation of an individual are driven by perception of that person while at the macro or societal level, aspects including policies and legislations influence behavior. This paper investigates marine littering through the macro-micro level lenses in order to analyze and recommend how anti-littering behavior can be improved and sustained. Using Coleman's model of micro-macro relations, research questions are formulated and investigated through a social survey. Results showed important differences in perceptions among participating groups and to address key issues, potential actions are proposed along with a framework to sustain anti-littering behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Does Short-term Litter Input Manipulation Affect Soil Respiration and the Carbon-isotopic Signature of Soil Respired CO2

    NASA Astrophysics Data System (ADS)

    Cheng, X.; Wu, J.

    2016-12-01

    Global change greatly alters the quality and quantity of plant litter inputs to soils, and further impacts soil organic matter (SOM) dynamics and soil respiration. However, the process-based understanding of how soil respiration may change with future shift in litter input is not fully understood. The Detritus Input and Removal Treatment (DIRT) experiment was conducted in coniferous forest (Platycladus orientalis (Linn.) Franco) ecosystem of central China to investigate the impact of above- and belowground litter input on soil respiration and the carbon-isotopic signature of soil respired CO2. Short-term (1-2 years) litter input manipulation significantly affected soil respiration, based on annual flux values, soil respiration was 31.9%, 20.5% and 37.2% lower in no litter (NL), no root (NR) and no input (NRNL), respectively, compared to control (CK). Whereas double litter (DL) treatment increased soil respiration by 9.1% compared to CK. The recalcitrance index of carbon (RIC) and the relative abundance of fungi increased under litter removal or root exclusion treatment (NL, NR and NRNL) compared to CK. Basal soil respiration was positively related to liable C and microbial biomass and negatively related to RIC and fungi to bacteria (F: B) ratio. The carbon-isotopic signature of soil respired CO2 enriched under litter removal and no input treatment, and slightly depleted under litter addition treatment compared to CK. Our results suggest that short-term litter input manipulation can affect the soil respiration by altering substrate availability and microbial community structure, and also impact the carbon-isotopic signature of soil respired CO2 possibly duo to change in the component of soil respiration and soil microclimate.

  20. Litter chemistry prevails over litter consumers in mediating effects of past steel industry activities on leaf litter decomposition.

    PubMed

    Lucisine, Pierre; Lecerf, Antoine; Danger, Michaël; Felten, Vincent; Aran, Delphine; Auclerc, Apolline; Gross, Elisabeth M; Huot, Hermine; Morel, Jean-Louis; Muller, Serge; Nahmani, Johanne; Maunoury-Danger, Florence

    2015-12-15

    Soil pollution has adverse effects on the performance and life history traits of microorganisms, plants, and animals, yet evidence indicates that even the most polluted sites can support structurally-complex and dynamic ecosystems. The present study aims at determining whether and how litter decomposition, one of the most important soil ecological processes leaf, is affected in a highly trace-metal polluted site. We postulated that past steel mill activities resulting in soil pollution and associated changes in soil characteristics would influence the rate of litter decomposition through two non-exclusive pathways: altered litter chemistry and responses of decomposers to lethal and sub-lethal toxic stress. We carried out a litter-bag experiment using Populus tremula L. leaf litter collected at, and allowed to decompose in, a trace metal polluted site and in three unpolluted sites used as controls. We designed a fully-factorial transplant experimental design to assess effects of litter origin and exposure site on the rate of litter decomposition. We further determined initial litter chemistry, fungal biomass, mesofauna abundance in litter bags, and the soil macrofauna community. Irrespective of the site of litter exposure, litter originating from the polluted site had a two-fold faster decomposition than litter from the unpolluted sites. Litter chemistry, notably the lignin content, seemed most important in explaining the degradation rate of the leaf litter. Abundance of meso and macro-detritivores was higher at the polluted site than at the unpolluted sites. However, litter decomposition proceeded at similar rates in polluted and unpolluted sites. Our results show that trace metal pollution and associated soil and litter changes do not necessarily weaken consumer control on litter decomposition through lethal and sub-lethal toxic stress. Copyright © 2015. Published by Elsevier B.V.

  1. Evaluation of different litter materials for broiler production in a hot and humid environment: 2. Productive performance and carcass characteristics.

    PubMed

    Garcês, Alice P J T; Afonso, Sónia M Santana; Chilundo, Abel; Jairoce, Chenjerai T S

    2017-02-01

    The availability of wood by-products for bedding material is falling in many regions due to rising demand for other uses. The objective of this study was to evaluate six alternative litter sources-river bed sand, coconut husk, rice hulls, Guinea grass, newspaper, and corncob-as a substitute for wood shavings (WS). The trial was carried out over 35 days in an open-sided and naturally ventilated broiler house under conditions of high ambient temperatures and relative humidity. During the brooding period (0 to 14 days), chicks raised on grass had lower (P < 0.05) footpad temperature than those grown on WS. After the brooding period (15 to 35 days), the temperatures of both litter and birds were higher (P < 0.05) for coconut husk than for WS. Grass litter resulted in lower (P < 0.05) final BW, FCR, and production efficiency. Sand and rice hulls were associated with lower (P < 0.05) survival rate and higher (P < 0.05) gizzard weight. Litter type did not affect carcass and meat yields. The footpad dermatitis score, associating incidence and severity, was not statistically different among the litter substrates tested, although numerically higher in coconut husk, grass, and corncob. The results obtained in this experiment indicate that, in a hot and humid environment, all materials except grass can be used as a substitute for wood shavings with comparable production efficiency.

  2. Effect of Fresh Poultry Litter and Compost on Soil Physical and Chemical Properties

    NASA Technical Reports Server (NTRS)

    Carr, Stacy; Tsegaye, Teferi; Coleman, Tommy

    1998-01-01

    Application of poultry litter and compost as a substitute for fertilizer not only uses unwanted waste and decreases expenditures for commercial fertilizer, it adds nutrients to soil for plant uptake. The properties of soil affected by poultry litter were analyzed to determine the positive and negative aspects of using this substitute fertilizer. This study focused on changes associated with saturated hydraulic conductivity, bulk density, nitrate concentrations, and pH after application of varying concentrations of poultry litter and compost. Soil samples from Tennessee Valley Substation in Alabama were analyzed in a laboratory at Alabama A&M University. As a result of the application of fresh poultry litter and compost, we found that the saturated hydraulic conductivity increased and the bulk density decreased, while the pH was generally not affected. Using poultry litter and compost as an alternative commercial fertilizers could be adapted by the farming community to protect the sustainability of our environment. Unwanted waste is used productively and soil is enriched for farming.

  3. Litter sex composition influences dominance status of Alpine marmots (Marmota marmota).

    PubMed

    Dupont, Pierre; Pradel, Roger; Lardy, Sophie; Allainé, Dominique; Cohas, Aurélie

    2015-11-01

    In social species, the hierarchical status of an individual has important consequences for its fitness. While many studies have focused on individual condition to explain access to dominance, very few have investigated the influence of the social environment, especially during early life. Yet it is known that environmental conditions early in life may influence several traits at adulthood. Here, we examine the influence of early social environment on accession to dominance by investigating the influence of litter size and sex composition on survival and the probability of ascending to dominance later in life using a 20-year dataset from a wild population of Alpine marmots (Marmota marmota). Although litter size had no effect on the fate of individuals, litter sex composition affected male juvenile survival and both male and female probabilities of reaching dominant status when adult. Male juveniles incur lower survival when the number of male juveniles in the litter increases, and individuals of both sexes from male-biased litters are more likely to become dominant than individuals from female-biased litters. However, the absolute number of sisters in the litter, rather than the sex ratio, seems to be an important predictor of the probability of acquiring dominant status: pups having more sisters are less likely to become dominant. Several potential mechanisms to explain these results are discussed.

  4. Zinc oxide nanoparticles affect carbon and nitrogen mineralization of Phoenix dactylifera leaf litter in a sandy soil.

    PubMed

    Rashid, Muhammad Imtiaz; Shahzad, Tanvir; Shahid, Muhammad; Ismail, Iqbal M I; Shah, Ghulam Mustafa; Almeelbi, Talal

    2017-02-15

    We investigated the impact of zinc oxide nanoparticles (ZnO NPs; 1000mgkg -1 soil) on soil microbes and their associated soil functions such as date palm (Phoenix dactylifera) leaf litter (5gkg -1 soil) carbon and nitrogen mineralization in mesocosms containing sandy soil. Nanoparticles application in litter-amended soil significantly decreased the cultivable heterotrophic bacterial and fungal colony forming units (cfu) compared to only litter-amended soil. The decrease in cfu could be related to lower microbial biomass carbon in nanoparticles-litter amended soil. Likewise, ZnO NPs also reduced CO 2 emission by 10% in aforementioned treatment but this was higher than control (soil only). Labile Zn was only detected in the microbial biomass of nanoparticles-litter applied soil indicating that microorganisms consumed this element from freely available nutrients in the soil. In this treatment, dissolved organic carbon and mineral nitrogen were 25 and 34% lower respectively compared to litter-amended soil. Such toxic effects of nanoparticles on litter decomposition resulted in 130 and 122% lower carbon and nitrogen mineralization efficiency respectively. Hence, our results entail that ZnO NPs are toxic to soil microbes and affect their function i.e., carbon and nitrogen mineralization of applied litter thus confirming their toxicity to microbial associated soil functions. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. The nutrition of poultry as a factor affecting litter quality and foot pad dermatitis - an updated review.

    PubMed

    Swiatkiewicz, S; Arczewska-Wlosek, A; Jozefiak, D

    2017-10-01

    Foot pad dermatitis (FPD), a condition of inflammation and necrotic lesions on the plantar surface of the footpads, is commonly observed in fast-growing broiler chickens and turkeys. FPD negatively affects the welfare of birds, performance indices and the economic profit of poultry meat production. Nutrition is an important factor affecting water intake, excreta moisture and litter quality and, in this way, the occurrence and intensity of FPD in birds. This article reviews and discusses the recent results published in the literature on the effects of nutritional factors on litter quality and FPD severity in broiler chickens and turkeys. Literature data on the efficacy of nutritional methods on the litter quality and FPD occurrence are not consistent. However, the results of several experiments indicate that the optimal level of crude protein, biotin and electrolytes (Na, K) in the diet, as well as feed additives such as feed enzymes hydrolysating non-starch polysaccharides and organic sources of microelements (zinc), may reduce the litter moisture as well as FPD incidence and severity in broiler chickens and turkey. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

  6. Microbial mineralization of organic nitrogen forms in poultry litters

    USDA-ARS?s Scientific Manuscript database

    Ammonia volatilization from the mineralization of uric acid and urea has a major impact on the poultry industry and the environment. Dry acids are a common management practice to reduce ammonia emissions from poultry houses, however little is known about how acidification affects the litter biologic...

  7. Does previous use affect litter box appeal in multi-cat households?

    PubMed

    Ellis, J J; McGowan, R T S; Martin, F

    2017-08-01

    It is commonly assumed that cats actively avoid eliminated materials (especially in multi-cat homes), suggesting regular litter box cleaning as the best defense against out-of-box elimination. The relationship between previous use and litter box appeal to familiar subsequent users is currently unknown. The purpose of this study was to investigate the relationship between previous litter box use and the identity of the previous user, type of elimination, odor, and presence of physical/visual obstructions in a multi-cat household scenario. Cats preferred a clean litter box to a dirty one, but the identity of the previous user had no impact on preferences. While the presence of odor from urine and/or feces did not impact litter box preferences, the presence of odorless faux-urine and/or feces did - with the presence of faux-feces being preferred over faux-urine. Results suggest neither malodor nor chemical communication play a role in litter box preferences, and instead emphasize the importance of regular removal of physical/visual obstructions as the key factor in promoting proper litter box use. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Marine Litter in the context of `G7' - Nothing but empty rhetoric?

    NASA Astrophysics Data System (ADS)

    Neumann, J.; Imhoff, H.

    2016-02-01

    The G7 summit 2015 in Germany has demonstrated that the major advanced economies mark a new path and mindset beyond their classical issues of world economy, foreign-, security-, and development policy - the protection of the marine environment. Focus themes were marine litter, deep-sea mining, and the protection of the high seas. In the G7 Leaders' Declaration they "acknowledge that marine litter, in particular plastic litter, poses a global challenge, directly affecting marine and coastal life and ecosystems […]". Based on priority actions defined in the annex to the Leaders' Declaration, termed the `G7 Action Plan to combat Marine Litter' (G7AP ML), in fact a novelty to the otherwise rather restrained political statements, the German Presidency aims at further defining and specifying actions that are listed in the `G7AP ML'. This will include inter alia explicit measures and timelines. Emphasizing the global importance and willingness of the G7 to act, and aiming at a swift implementation of the action plan with the intention to establish a real and realistic tool in the race of litter input vs. reduction of anthropogenic pressure on the marine environment, is key to the envisaged approach. Thus, building on existing experiences, such as the OSPAR Regional Action Plan on Marine Litter for the North-East Atlantic, it is intended to expand the geographical range of application towards a global perspective. What has been learned - e.g. concerning the need of close collaboration with stakeholders? What has been decided - on how implementation may be done in reality? And is the `G7AP ML' a valuable add-on to other initiatives, e.g. Global Partnership on Marine Litter - United Nations Environment Programme (UNEP)? These questions will be discussed in the light of the state of the art of the G7 marine litter topic.

  9. Effects of Litter Manipulation on Litter Decomposition in a Successional Gradients of Tropical Forests in Southern China

    PubMed Central

    Chen, Hao; Gurmesa, Geshere A.; Liu, Lei; Zhang, Tao; Fu, Shenglei; Liu, Zhanfeng; Dong, Shaofeng; Ma, Chuan; Mo, Jiangming

    2014-01-01

    Global changes such as increasing CO2, rising temperature, and land-use change are likely to drive shifts in litter inputs to forest floors, but the effects of such changes on litter decomposition remain largely unknown. We initiated a litter manipulation experiment to test the response of litter decomposition to litter removal/addition in three successional forests in southern China, namely masson pine forest (MPF), mixed coniferous and broadleaved forest (MF) and monsoon evergreen broadleaved forest (MEBF). Results showed that litter removal decreased litter decomposition rates by 27%, 10% and 8% and litter addition increased litter decomposition rates by 55%, 36% and 14% in MEBF, MF and MPF, respectively. The magnitudes of changes in litter decomposition were more significant in MEBF forest and less significant in MF, but not significant in MPF. Our results suggest that change in litter quantity can affect litter decomposition, and this impact may become stronger with forest succession in tropical forest ecosystem. PMID:24901698

  10. Plant litter decomposition and nutrient release in peatlands

    NASA Astrophysics Data System (ADS)

    Bragazza, Luca; Buttler, Alexandre; Siegenthaler, Andy; Mitchell, Edward A. D.

    Decomposition of plant litter is a crucial process in controlling the carbon balance of peatlands. Indeed, as long as the rate of litter decomposition remains lower than the rate of above- and belowground litter production, a net accumulation of peat and, thus, carbon will take place. In addition, decomposition controls the release of important nutrients such as nitrogen, phosphorus, and potassium, the availability of which affects the structure and the functioning of plant communities. This chapter describes the role of the main drivers in affecting mass loss and nutrient release from recently deposited plant litter. In particular, the rate of mass loss of Sphagnum litter and vascular plant litter is reviewed in relation to regional climatic conditions, aerobic/anaerobic conditions, and litter chemistry. The rate of nutrient release is discussed in relation to the rate of mass loss and associated litter chemistry by means of a specific case study.

  11. Litter type affects the activity of aerobic decomposers in a boreal peatland more than site nutrient and water level regimes

    NASA Astrophysics Data System (ADS)

    Straková, P.; Niemi, R. M.; Freeman, C.; Peltoniemi, K.; Toberman, H.; Heiskanen, I.; Fritze, H.; Laiho, R.

    2011-02-01

    Peatlands are carbon (C) storage ecosystems sustained by a high water level (WL). High WL creates anoxic conditions that suppress the activity of aerobic decomposers and provide conditions for peat accumulation. Peatland function can be dramatically affected by WL drawdown caused by land-use and/or climate change. Aerobic decomposers are directly affected by WL drawdown through environmental factors such as increased oxygenation and nutrient availability. Additionally, they are indirectly affected via changes in plant community composition and litter quality. We studied the relative importance of direct and indirect effects of WL drawdown on aerobic decomposer activity in plant litter. We did this by profiling 11 extracellular enzymes involved in the mineralization of organic C, nitrogen, phosphorus and sulphur. Our study sites represented a three-stage chronosequence from pristine (undrained) to short-term (years) and long-term (decades) WL drawdown conditions under two nutrient regimes. The litter types included reflected the prevalent vegetation, i.e., Sphagnum mosses, graminoids, shrubs and trees. WL drawdown had a direct and positive effect on microbial activity. Enzyme allocation shifted towards C acquisition, which caused an increase in the rate of decomposition. However, litter type overruled the direct effects of WL drawdown and was the main factor shaping microbial activity patterns. Our results imply that changes in plant community composition in response to persistent WL drawdown will strongly affect the C dynamics of peatlands.

  12. Pulse frequency and soil-litter mixing alter the control of cumulative precipitation over litter decomposition.

    PubMed

    Joly, François-Xavier; Kurupas, Kelsey L; Throop, Heather L

    2017-09-01

    Macroclimate has traditionally been considered the predominant driver of litter decomposition. However, in drylands, cumulative monthly or annual precipitation typically fails to predict decomposition. In these systems, the windows of opportunity for decomposer activity may rather depend on the precipitation frequency and local factors affecting litter desiccation, such as soil-litter mixing. We used a full-factorial microcosm experiment to disentangle the relative importance of cumulative precipitation, pulse frequency, and soil-litter mixing on litter decomposition. Decomposition, measured as litter carbon loss, saturated with increasing cumulative precipitation when pulses were large and infrequent, suggesting that litter moisture no longer increased and/or microbial activity was no longer limited by water availability above a certain pulse size. More frequent precipitation pulses led to increased decomposition at high levels of cumulative precipitation. Soil-litter mixing consistently increased decomposition, with greatest relative increase (+194%) under the driest conditions. Collectively, our results highlight the need to consider precipitation at finer temporal scale and incorporate soil-litter mixing as key driver of decomposition in drylands. © 2017 by the Ecological Society of America.

  13. Effects of prescribed burning and litter type on litter decomposition and nutrient release in mixed-grass prairie in Eastern Montana

    USDA-ARS?s Scientific Manuscript database

    Fire can affect litter decomposition and carbon (C) and nitrogen (N) dynamics. Here, we examined the effect of summer fire and three litter types on litter decomposition and litter C and N dynamics in a northern mixed-grass prairie over a 24 month period starting ca. 14 months after fire. Over all...

  14. Litter Ammonia Generation: Moisture Content and Organic vs. Inorganic Bedding Materials

    USDA-ARS?s Scientific Manuscript database

    Negative impacts on the environment, bird well-being, and farm worker health indicate the need for abatement strategies for poultry litter NH3 generation. Type of bedding affects many parameters related to poultry production including NH3 losses. Broiler excrement was mixed with pine wood shavings, ...

  15. Plant litter functional diversity effects on litter mass loss depend on the macro-detritivore community.

    PubMed

    Patoine, Guillaume; Thakur, Madhav P; Friese, Julia; Nock, Charles; Hönig, Lydia; Haase, Josephine; Scherer-Lorenzen, Michael; Eisenhauer, Nico

    2017-11-01

    A better understanding of the mechanisms driving litter diversity effects on decomposition is needed to predict how biodiversity losses affect this crucial ecosystem process. In a microcosm study, we investigated the effects of litter functional diversity and two major groups of soil macro-detritivores on the mass loss of tree leaf litter mixtures. Furthermore, we tested the effects of litter trait community means and dissimilarity on litter mass loss for seven traits relevant to decomposition. We expected macro-detritivore effects on litter mass loss to be most pronounced in litter mixtures of high functional diversity. We used 24 leaf mixtures differing in functional diversity, which were composed of litter from four species from a pool of 16 common European tree species. Earthworms, isopods, or a combination of both were added to each litter combination for two months. Litter mass loss was significantly higher in the presence of earthworms than in that of isopods, whereas no synergistic effects of macro-detritivore mixtures were found. The effect of functional diversity of the litter material was highest in the presence of both macro-detritivore groups, supporting the notion that litter diversity effects are most pronounced in the presence of different detritivore species. Species-specific litter mass loss was explained by nutrient content, secondary compound concentration, and structural components. Moreover, dissimilarity in N concentrations increased litter mass loss, probably because detritivores having access to nutritionally diverse food sources. Furthermore, strong competition between the two macro-detritivores for soil surface litter resulted in a decrease of survival of both macro-detritivores. These results show that the effects of litter functional diversity on decomposition are contingent upon the macro-detritivore community and composition. We conclude that the temporal dynamics of litter trait diversity effects and their interaction with

  16. Plant litter functional diversity effects on litter mass loss depend on the macro-detritivore community

    PubMed Central

    Patoine, Guillaume; Thakur, Madhav P.; Friese, Julia; Nock, Charles; Hönig, Lydia; Haase, Josephine; Scherer-Lorenzen, Michael; Eisenhauer, Nico

    2017-01-01

    A better understanding of the mechanisms driving litter diversity effects on decomposition is needed to predict how biodiversity losses affect this crucial ecosystem process. In a microcosm study, we investigated the effects of litter functional diversity and two major groups of soil macro-detritivores on the mass loss of tree leaf litter mixtures. Furthermore, we tested the effects of litter trait community means and dissimilarity on litter mass loss for seven traits relevant to decomposition. We expected macro-detritivore effects on litter mass loss to be most pronounced in litter mixtures of high functional diversity. We used 24 leaf mixtures differing in functional diversity, which were composed of litter from four species from a pool of 16 common European tree species. Earthworms, isopods, or a combination of both were added to each litter combination for two months. Litter mass loss was significantly higher in the presence of earthworms than in that of isopods, whereas no synergistic effects of macro-detritivore mixtures were found. The effect of functional diversity of the litter material was highest in the presence of both macro-detritivore groups, supporting the notion that litter diversity effects are most pronounced in the presence of different detritivore species. Species-specific litter mass loss was explained by nutrient content, secondary compound concentration, and structural components. Moreover, dissimilarity in N concentrations increased litter mass loss, probably because detritivores having access to nutritionally diverse food sources. Furthermore, strong competition between the two macro-detritivores for soil surface litter resulted in a decrease of survival of both macro-detritivores. These results show that the effects of litter functional diversity on decomposition are contingent upon the macro-detritivore community and composition. We conclude that the temporal dynamics of litter trait diversity effects and their interaction with

  17. Photodegradation of roxarsone in poultry litter leachates

    USGS Publications Warehouse

    Bednar, A.J.; Garbarino, J.R.; Ferrer, I.; Rutherford, D.W.; Wershaw, R. L.; Ranville, J.F.; Wildeman, T.R.

    2003-01-01

    Arsenic compounds have been used extensively in agriculture in the US for applications ranging from cotton herbicides to animal feed supplements. Roxarsone (3-nitro-4-hydroxyphenylarsonic acid), in particular, is used widely in poultry production to control coccidial intestinal parasites. It is excreted unchanged in the manure and introduced into the environment when litter is applied to farmland as fertilizer. Although the toxicity of roxarsone is less than that of inorganic arsenic, roxarsone can degrade, biotically and abiotically, to produce more toxic inorganic forms of arsenic, such as arsenite and arsenate. Experiments were conducted on aqueous litter leachates to test the stability of roxarsone under different conditions. Laboratory experiments have shown that arsenite can be cleaved photolytically from the roxarsone moiety at pH 4-8 and that the degradation rate increases with increasing pH. Furthermore, the rate of photodegradation increases with nitrate and natural organic matter concentration, reactants that are commonly found in poultry-litter-water leachates. Additional photochemical reactions rapidly oxidize the cleaved arsenite to arsenate. The formation of arsenate is not entirely undesirable, because it is less mobile in soil systems and less toxic than arsenite. A possible mechanism for the degradation of roxarsone in poultry litter leachates is proposed. The results suggest that poultry litter storage and field application practices could affect the degradation of roxarsone and subsequent mobilization of inorganic arsenic species. ?? 2002 Elsevier Science B.V. All rights reserved.

  18. Litter quality mediated nitrogen effect on plant litter decomposition regardless of soil fauna presence.

    PubMed

    Zhang, Weidong; Chao, Lin; Yang, Qingpeng; Wang, Qingkui; Fang, Yunting; Wang, Silong

    2016-10-01

    Nitrogen addition has been shown to affect plant litter decomposition in terrestrial ecosystems. The way that nitrogen deposition impacts the relationship between plant litter decomposition and altered soil nitrogen availability is unclear, however. This study examined 18 co-occurring litter types in a subtropical forest in China in terms of their decomposition (1 yr of exposure in the field) with nitrogen addition treatment (0, 0.4, 1.6, and 4.0 mol·N·m -2 ·yr -1 ) and soil fauna exclusion (litter bags with 0.1 and 2 cm mesh size). Results showed that the plant litter decomposition rate is significantly reduced because of nitrogen addition; the strength of the nitrogen addition effect is closely related to the nitrogen addition levels. Plant litters with diverse quality responded to nitrogen addition differently. When soil fauna was present, the nitrogen addition effect on medium-quality or high-quality plant litter decomposition rate was -26% ± 5% and -29% ± 4%, respectively; these values are significantly higher than that of low-quality plant litter decomposition. The pattern is similar when soil fauna is absent. In general, the plant litter decomposition rate is decreased by soil fauna exclusion; an average inhibition of -17% ± 1.5% was exhibited across nitrogen addition treatment and litter quality groups. However, this effect is weakly related to nitrogen addition treatment and plant litter quality. We conclude that the variations in plant litter quality, nitrogen deposition, and soil fauna are important factors of decomposition and nutrient cycling in a subtropical forest ecosystem. © 2016 by the Ecological Society of America.

  19. Citizen scientists reveal: Marine litter pollutes Arctic beaches and affects wild life.

    PubMed

    Bergmann, Melanie; Lutz, Birgit; Tekman, Mine B; Gutow, Lars

    2017-12-15

    Recent data indicate accumulation areas of marine litter in Arctic waters and significant increases over time. Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists on six beaches of Svalbard. Litter quantities recorded by cruise tourists varied from 9-524gm -2 and were similar to those from densely populated areas. Plastics accounted for >80% of the overall litter, most of which originated from fisheries. Photographs provided by citizens show deleterious effects of beach litter on Arctic wildlife, which is already under strong pressure from global climate change. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. The results stress once more that current legislative frameworks are insufficient to tackle the pollution of Arctic ecosystems. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Litter quality versus soil microbial community controls over decomposition: a quantitative analysis

    USGS Publications Warehouse

    Cleveland, Cory C.; Reed, Sasha C.; Keller, Adrienne B.; Nemergut, Diana R.; O'Neill, Sean P.; Ostertag, Rebecca; Vitousek, Peter M.

    2014-01-01

    The possible effects of soil microbial community structure on organic matter decomposition rates have been widely acknowledged, but are poorly understood. Understanding these relationships is complicated by the fact that microbial community structure and function are likely to both affect and be affected by organic matter quality and chemistry, thus it is difficult to draw mechanistic conclusions from field studies. We conducted a reciprocal soil inoculum × litter transplant laboratory incubation experiment using samples collected from a set of sites that have similar climate and plant species composition but vary significantly in bacterial community structure and litter quality. The results showed that litter quality explained the majority of variation in decomposition rates under controlled laboratory conditions: over the course of the 162-day incubation, litter quality explained nearly two-thirds (64 %) of variation in decomposition rates, and a smaller proportion (25 %) was explained by variation in the inoculum type. In addition, the relative importance of inoculum type on soil respiration increased over the course of the experiment, and was significantly higher in microcosms with lower litter quality relative to those with higher quality litter. We also used molecular phylogenetics to examine the relationships between bacterial community composition and soil respiration in samples through time. Pyrosequencing revealed that bacterial community composition explained 32 % of the variation in respiration rates. However, equal portions (i.e., 16 %) of the variation in bacterial community composition were explained by inoculum type and litter quality, reflecting the importance of both the meta-community and the environment in bacterial assembly. Taken together, these results indicate that the effects of changing microbial community composition on decomposition are likely to be smaller than the potential effects of climate change and/or litter quality changes in

  1. Odour emissions from poultry litter - A review litter properties, odour formation and odorant emissions from porous materials.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2016-07-15

    Odour emissions from meat chicken sheds can at times cause odour impacts on surrounding communities. Litter is seen as the primary source of this odour. Formation and emission of odour from meat chicken litter during the grow-out period are influenced by various factors such as litter conditions, the environment, microbial activity, properties of the odorous gases and management practices. Odour emissions vary spatially and temporally. This variability has made it challenging to understand how specific litter conditions contribute to odour emissions from the litter and production sheds. Existing knowledge on odorants, odour formation mechanisms and emission processes that contribute to odour emissions from litter are reviewed. Litter moisture content and water thermodynamics (i.e. water activity, Aw) are also examined as factors that contribute to microbial odour formation, physical litter conditions and the exchange of individual odorant gases at the air-water interface. Substantial opportunities exist for future research on litter conditions and litter formation mechanisms and how these contribute to odour emissions. Closing this knowledge gap will improve management strategies that intercept and interfere with odour formation and emission processes leading to an overall reduction in the potential to cause community impacts. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  2. The impact of alum addition on organic P transformations in poultry litter and litter-amended soil.

    PubMed

    Warren, Jason G; Penn, Chad J; McGrath, Joshua M; Sistani, Karamat

    2008-01-01

    Poultry litter treatment with alum (Al(2)(SO(4))(3) . 18H(2)O) lowers litter phosphorus (P) solubility and therefore can lower litter P release to runoff after land application. Lower P solubility in litter is generally attributed to aluminum-phosphate complex formation. However, recent studies suggest that alum additions to poultry litter may influence organic P mineralization. Therefore, alum-treated and untreated litters were incubated for 93 d to assess organic P transformations during simulated storage. A 62-d soil incubation was also conducted to determine the fate of incorporated litter organic P, which included alum-treated litter, untreated litter, KH(2)PO(4) applied at 60 mg P kg(-1) of soil, and an unamended control. Liquid-state (31)P nuclear magnetic resonance indicated that phytic acid was the only organic P compound present, accounting for 50 and 45% of the total P in untreated and alum-treated litters, respectively, before incubation and declined to 9 and 37% after 93 d of storage-simulating incubation. Sequential fractionation of litters showed that alum addition to litter transformed 30% of the organic P from the 1.0 mol L(-1) HCl to the 0.1 mol L(-1) NaOH extractable fraction and that both organic P fractions were more persistent in alum-treated litter compared with untreated litter. The soil incubation revealed that 0.1 mol L(-1) NaOH-extractable organic P was more recalcitrant after mixing than was the 1.0 mol L(-1) HCl-extractable organic P. Thus, adding alum to litter inhibits organic P mineralization during storage and promotes the formation of alkaline extractable organic P that sustains lower P solubility in the soil environment.

  3. Flower litters of alpine plants affect soil nitrogen and phosphorus rapidly in the eastern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Wang, Jinniu; Xu, Bo; Wu, Yan; Gao, Jing; Shi, Fusun

    2016-10-01

    Litters of reproductive organs have rarely been studied despite their role in allocating nutrients for offspring reproduction. This study determines the mechanism through which flower litters efficiently increase the available soil nutrient pool. Field experiments were conducted to collect plant litters and calculate biomass production in an alpine meadow of the eastern Tibetan Plateau. C, N, P, lignin, cellulose content, and their relevant ratios of litters were analyzed to identify their decomposition features. A pot experiment was performed to determine the effects of litter addition on the soil nutrition pool by comparing the treated and control samples. The litter-bag method was used to verify decomposition rates. The flower litters of phanerophyte plants were comparable with non-flower litters. Biomass partitioning of other herbaceous species accounted for 10-40 % of the aboveground biomass. Flower litter possessed significantly higher N and P levels but less C / N, N / P, lignin / N, and lignin and cellulose concentrations than leaf litter. The litter-bag experiment confirmed that the flower litters of Rhododendron przewalskii and Meconopsis integrifolia decompose approximately 3 times faster than mixed litters within 50 days. Pot experiment findings indicated that flower litter addition significantly increased the available nutrient pool and soil microbial productivity. The time of litter fall significantly influenced soil available N and P, and soil microbial biomass. Flower litters fed the soil nutrition pool and influenced nutrition cycling in alpine ecosystems more efficiently because of their non-ignorable production, faster decomposition rate, and higher nutrient contents compared with non-flower litters. The underlying mechanism can enrich nutrients, which return to the soil, and non-structural carbohydrates, which feed and enhance the transitions of soil microorganisms.

  4. Cigarette Litter: Smokers’ Attitudes and Behaviors

    PubMed Central

    Rath, Jessica M.; Rubenstein, Rebecca A.; Curry, Laurel E.; Shank, Sarah E.; Cartwright, Julia C.

    2012-01-01

    Cigarette butts are consistently the most collected items in litter clean-up efforts, which are a costly burden to local economies. In addition, tobacco waste may be detrimental to our natural environment. The tobacco industry has conducted or funded numerous studies on smokers’ littering knowledge and behavior, however, non-industry sponsored research is rare. We sought to examine whether demographics and smokers’ knowledge and beliefs toward cigarette waste as litter predicts littering behavior. Smokers aged 18 and older (n = 1,000) were interviewed about their knowledge and beliefs towards cigarette waste as litter. Respondents were members of the Research Now panel, an online panel of over three million respondents in the United States. Multivariate logistic regressions were conducted to determine factors significantly predictive of ever having littered cigarette butts or having littered cigarette butts within the past month (p-value < 0.05). The majority (74.1%) of smokers reported having littered cigarette butts at least once in their life, by disposing of them on the ground or throwing them out of a car window. Over half (55.7%) reported disposing of cigarette butts on the ground, in a sewer/gutter, or down a drain in the past month. Those who did not consider cigarette butts to be litter were over three and half times as likely to report having ever littered cigarette butts (OR = 3.68, 95%CI = 2.04, 6.66) and four times as likely to have littered cigarette butts in the past month (OR = 4.00, 95%CI = 2.53, 6.32). Males were significantly more likely to have littered cigarette butts in the past month compared to females (OR = 1.49, 95%CI = 1.14, 1.94). Holding the belief that cigarette butts are not litter was the only belief in this study that predicted ever or past-month littering of cigarette waste. Messages in anti-cigarette-litter campaigns should emphasize that cigarette butts are not just litter but are toxic waste and are harmful when disposed of

  5. Bacterial contamination of boar semen affects the litter size.

    PubMed

    Maroto Martín, Luis O; Muñoz, Eduardo Cruz; De Cupere, Françoise; Van Driessche, Edilbert; Echemendia-Blanco, Dannele; Rodríguez, José M Machado; Beeckmans, Sonia

    2010-07-01

    One hundred and fifteen semen samples were collected from 115 different boars from two farms in Cuba. The boars belonged to five different breeds. Evaluation of the semen sample characteristics (volume, pH, colour, smell, motility of sperm cells) revealed that they meet international standards. The samples were also tested for the presence of agglutinated sperm cells and for bacterial contamination. Seventy five percent of the ejaculates were contaminated with at least one type of bacteria and E. coli was by far the major contaminant, being present in 79% of the contaminated semen samples (n=68). Other contaminating bacteria belonged to the genera Proteus (n=31), Serratia (n=31), Enterobacter (n=24), Klebsiella (n=12), Staphylococcus (n=10), Streptococcus (n=8) and Pseudomonas (n=7). Only in one sample anaerobic bacteria were detected. Pearson's analysis of the data revealed that there is a positive correlation between the presence of E. coli and sperm agglutination, and a negative correlation between sperm agglutination and litter size. One-way ANOVA and post hoc Tukey analysis of 378 litters showed that the litter size is significantly reduced when semen is used that is contaminated with spermagglutinating E. coli above a threshold value of 3.5x10(3)CFU/ml. Copyright 2010 Elsevier B.V. All rights reserved.

  6. Anti-Litter Curriculum Packet, Interdisciplinary, K-12.

    ERIC Educational Resources Information Center

    Tillis, Richard

    This curriculum packet consists of 20 illustrated cards with 15 activities designed to create "positive feelings" about a clean environment. Activities range from picture coloring for younger students, to lessons such as the economic and health problems litter creates for older students. Objectives include encouraging anti-litter and…

  7. Environmental fate of roxarsone in poultry litter. Part II. Mobility of arsenic in soils amended with poultry litter

    USGS Publications Warehouse

    Rutherford, D.W.; Bednar, A.J.; Garbarino, J.R.; Needham, R.; Staver, K.W.; Wershaw, R. L.

    2003-01-01

    Poultry litter often contains arsenic as a result of organo-arsenical feed additives. When the poultry litter is applied to agricultural fields, the arsenic is released to the environment and may result in increased arsenic in surface and groundwater and increased uptake by plants. The release of arsenic from poultry litter, litter-amended soils, and soils without litter amendment was examined by extraction with water and strong acids (HCI and HN03). The extracts were analyzed for As, C, P, Cu, Zn, and Fe. Copper, zinc, and iron are also poultry feed additives. Soils with a known history of litter application and controlled application rate of arsenic-containing poultry litter were obtained from the University of Maryland Agricultural Experiment Station. Soils from fields with long-term application of poultry litter were obtained from a tilled field on the Delmarva Peninsula (MD) and an untilled Oklahoma pasture. Samples from an adjacent forest or nearby pasture that had no history of litter application were used as controls. Depth profiles were sampled for the Oklahoma pasture soils. Analysis of the poultry litter showed that 75% of the arsenic was readily soluble in water. Extraction of soils shows that weakly bound arsenic mobilized by water correlates positively with C, P, Cu, and Zn in amended fields and appears to come primarily from the litter. Strongly bound arsenic correlates positively with Fe in amended fields and suggests sorption or coprecipitation of As and Fe in the soil column.

  8. Natural zeolites in diet or litter of broilers.

    PubMed

    Schneider, A F; Almeida, D S De; Yuri, F M; Zimmermann, O F; Gerber, M W; Gewehr, C E

    2016-04-01

    This study aims to analyse the influence of adding natural zeolites (clinoptilolite) to the diet or litter of broilers and their effects on growth performance, carcass yield and litter quality. Three consecutive flocks of broilers were raised on the same sawdust litter, from d 1 to d 42 of age, and distributed in three treatments (control with no added zeolites, addition of 5 g/kg zeolite to diet and addition of 100 g/kg zeolites to litter). The addition of zeolites to the diet or litter did not affect growth performance or carcass yield. The addition of zeolites to the diet did not influence moisture content of the litter, ammonia volatilisation was reduced only in the first flock and pH of litter was reduced in the second and third flock. However, the addition of zeolites to the litter reduced moisture content, litter pH and ammonia volatilisation in all flocks analysed. The addition of 5 g/kg zeolite to the diet in three consecutive flocks was not effective in maintaining litter quality, whereas the addition of 100 g/kg natural zeolites to sawdust litter reduced litter moisture and ammonia volatilisation in three consecutive flocks raised on the same litter.

  9. Does litter size variation affect models of terrestrial carnivore extinction risk and management?

    PubMed

    Devenish-Nelson, Eleanor S; Stephens, Philip A; Harris, Stephen; Soulsbury, Carl; Richards, Shane A

    2013-01-01

    Individual variation in both survival and reproduction has the potential to influence extinction risk. Especially for rare or threatened species, reliable population models should adequately incorporate demographic uncertainty. Here, we focus on an important form of demographic stochasticity: variation in litter sizes. We use terrestrial carnivores as an example taxon, as they are frequently threatened or of economic importance. Since data on intraspecific litter size variation are often sparse, it is unclear what probability distribution should be used to describe the pattern of litter size variation for multiparous carnivores. We used litter size data on 32 terrestrial carnivore species to test the fit of 12 probability distributions. The influence of these distributions on quasi-extinction probabilities and the probability of successful disease control was then examined for three canid species - the island fox Urocyon littoralis, the red fox Vulpes vulpes, and the African wild dog Lycaon pictus. Best fitting probability distributions differed among the carnivores examined. However, the discretised normal distribution provided the best fit for the majority of species, because variation among litter-sizes was often small. Importantly, however, the outcomes of demographic models were generally robust to the distribution used. These results provide reassurance for those using demographic modelling for the management of less studied carnivores in which litter size variation is estimated using data from species with similar reproductive attributes.

  10. Flood pattern and weather determine Populus leaf litter breakdown and nitrogen dynamics on a cold desert floodplain

    USGS Publications Warehouse

    Andersen, D.C.; Nelson, S.M.

    2006-01-01

    Patterns and processes involved in litter breakdown on desert river floodplains are not well understood. We used leafpacks containing Fremont cottonwood (Populus deltoides subsp. wislizenii) leaf litter to investigate the roles of weather and microclimate, flooding (immersion), and macroinvertebrates on litter organic matter (OM) and nitrogen (N) loss on a floodplain in a cool-temperate semi-arid environment (Yampa River, northwestern Colorado, USA). Total mass of N in fresh autumn litter fell by ∼20% over winter and spring, but in most cases there was no further N loss prior to termination of the study after 653 days exposure, including up to 20 days immersion during the spring flood pulse. Final OM mass was 10–40% of initial values. The pattern of OM and N losses suggested most N would be released outside the flood season, when retention within the floodplain would be likely. The exclusion of macroinvertebrates modestly reduced the rate of OM loss (by about 10%) but had no effect on N dynamics over nine months. Immersion in floodwater accelerated OM loss, but modest variation in litter quality did not affect the breakdown rate. These results are consistent with the concept that decomposition on desert floodplains progresses much as does litter processing in desert uplands, but with periodic bouts of processing typical of aquatic environments when litter is inundated by floodwaters. The strong dependence of litter breakdown rate on weather and floods means that climate change or river flow management can easily disrupt floodplain nutrient dynamics.

  11. Evaluation of broiler litter transportation in northern Alabama, USA.

    PubMed

    Paudel, Krishna P; Adhikari, Murali; Martin, Neil R

    2004-10-01

    The profitability of using broiler litter as a source of crop nutrients was calculated using a phosphorus-consistent litter application rule. A ton of litter can cost effectively be transported up to 164 miles from the production facility. A cost-minimizing phosphorus-consistent transportation model developed to meet the nutrient needs of 29 counties in northern Alabama revealed that not all of the litter can be utilized in the region. The total cost increased when transportation of the litter out of the heavily surplus counties was prioritized. Total litter use was minimally affected by changes in chemical fertilizer prices. Shadow prices indicated the robustness of the model.

  12. Carbon redistribution during interrill erosion in subtropical forests: Effects of leaf litter diversity and soil fauna

    NASA Astrophysics Data System (ADS)

    Goebes, Philipp; Seitz, Steffen; Kühn, Peter; Scholten, Thomas

    2016-04-01

    Soil erosion is crucial for degradation of carbon (C) from their pools in the soil. If C of the eroded sediment and runoff are not only related to soil pools but also resulting additively from decomposition of litter cover, the system gets more complex. The role of these amounts for C cycling in a forest environment is not yet known properly and thus, the aim of this study was to investigate the role of leaf litter diversity, litter cover and soil fauna on C redistribution during interrill erosion. We established 96 runoff plots that were deployed with seven domestic leaf litter species resulting in none species (bare ground), 1-species, 2-species and 4-species mixtures. Every second runoff plot was equipped with a fauna extinction feature to investigate the role of soil meso- and macrofauna. Erosion processes were initiated using a rainfall simulator at two time steps (summer 2012 and autumn 2012) to investigate the role of leaf litter decomposition on C redistribution. C fluxes during 20 min rainfall simulation were 99.13 ± 94.98 g/m². C fluxes and C contents both were affected by soil fauna. C fluxes were higher with presence of soil fauna due to loosening and slackening of the soil surface rather than due to faster decomposition of leaves. In contrast, C contents were higher in the absence of soil fauna possibly resulting from a missing dilution effect in the top soil layer. Leaf litter diversity did not affect C fluxes, but indirectly affected C contents as it increased the soil fauna effect with higher leaf litter diversity due to superior food supply. Initial C contents in the soil mainly determined those of the eroded sediment. For future research, it will be essential to introduce a long-term decomposition experiment to get further insights into the processes of C redistribution.

  13. Does Litter Size Variation Affect Models of Terrestrial Carnivore Extinction Risk and Management?

    PubMed Central

    Devenish-Nelson, Eleanor S.; Stephens, Philip A.; Harris, Stephen; Soulsbury, Carl; Richards, Shane A.

    2013-01-01

    Background Individual variation in both survival and reproduction has the potential to influence extinction risk. Especially for rare or threatened species, reliable population models should adequately incorporate demographic uncertainty. Here, we focus on an important form of demographic stochasticity: variation in litter sizes. We use terrestrial carnivores as an example taxon, as they are frequently threatened or of economic importance. Since data on intraspecific litter size variation are often sparse, it is unclear what probability distribution should be used to describe the pattern of litter size variation for multiparous carnivores. Methodology/Principal Findings We used litter size data on 32 terrestrial carnivore species to test the fit of 12 probability distributions. The influence of these distributions on quasi-extinction probabilities and the probability of successful disease control was then examined for three canid species – the island fox Urocyon littoralis, the red fox Vulpes vulpes, and the African wild dog Lycaon pictus. Best fitting probability distributions differed among the carnivores examined. However, the discretised normal distribution provided the best fit for the majority of species, because variation among litter-sizes was often small. Importantly, however, the outcomes of demographic models were generally robust to the distribution used. Conclusion/Significance These results provide reassurance for those using demographic modelling for the management of less studied carnivores in which litter size variation is estimated using data from species with similar reproductive attributes. PMID:23469140

  14. Effects of top-dressing recycled broiler litter on litter production, litter characteristics, and nitrogen mass balance.

    PubMed

    Coufal, C D; Chavez, C; Niemeyer, P R; Carey, J B

    2006-03-01

    Top-dressing is a method of broiler litter management in which a thin layer of new, clean litter material is spread over the top of previously used litter prior to placement of a new flock. This fresh layer of bedding material increases the absorptive capacity of the litter and decreases litter caking. Although this practice has been widely used in the poultry industry for many years, no research has been conducted to quantify the effects the practice has on broiler performance, litter production rates, and nutrient content, or the ability of broiler litter to retain manure N and prevent volatilization. An experiment was conducted to quantify these parameters under simulated commercial conditions in a research facility. Nine consecutive flocks of broilers were reared on recycled broiler litter that had previously been used for 9 flocks. Control pens received no litter treatment whereas top-dressed pens received a thin layer of new rice hulls (1 to 2 cm) before the placement of each flock. Nitrogen loss was calculated using the mass balance method. Average broiler performance was not different between the top-dressed and control pens. Top-dressing of litter significantly (P < 0.05) reduced caked litter production compared with control pens in 6 of 9 flocks. However, average total litter production over all 9 flocks was not different between the 2 litter management strategies. In all flocks, litter N content was significantly reduced in top-dressed pens compared with control pens. As a result, litter C:N ratios were significantly higher for pens with top-dressed litter. Differences in N loss between the treatments were not consistent. Average N loss for all flocks was 10.61 and 11.92 g of N/kg of marketed broiler for control and top-dressed pens, respectively, or 20.1 and 22.5% of N inputs, respectively. Based on this experiment, top-dressing of recycled broiler litter would not be recommended as a strategy to reduce the volatilization of N from broiler rearing

  15. Effects of fire frequency on litter decomposition as mediated by changes to litter chemistry and soil environmental conditions.

    PubMed

    Ficken, Cari D; Wright, Justin P

    2017-01-01

    Litter quality and soil environmental conditions are well-studied drivers influencing decomposition rates, but the role played by disturbance legacy, such as fire history, in mediating these drivers is not well understood. Fire history may impact decomposition directly, through changes in soil conditions that impact microbial function, or indirectly, through shifts in plant community composition and litter chemistry. Here, we compared early-stage decomposition rates across longleaf pine forest blocks managed with varying fire frequencies (annual burns, triennial burns, fire-suppression). Using a reciprocal transplant design, we examined how litter chemistry and soil characteristics independently and jointly influenced litter decomposition. We found that both litter chemistry and soil environmental conditions influenced decomposition rates, but only the former was affected by historical fire frequency. Litter from annually burned sites had higher nitrogen content than litter from triennially burned and fire suppression sites, but this was correlated with only a modest increase in decomposition rates. Soil environmental conditions had a larger impact on decomposition than litter chemistry. Across the landscape, decomposition differed more along soil moisture gradients than across fire management regimes. These findings suggest that fire frequency has a limited effect on litter decomposition in this ecosystem, and encourage extending current decomposition frameworks into disturbed systems. However, litter from different species lost different masses due to fire, suggesting that fire may impact decomposition through the preferential combustion of some litter types. Overall, our findings also emphasize the important role of spatial variability in soil environmental conditions, which may be tied to fire frequency across large spatial scales, in driving decomposition rates in this system.

  16. Correlation of foliage and litter chemistry of sugar maple, Acer saccharum, as affected by elevated CO2 and varying N availability, and effects on decomposition

    Treesearch

    J. S. King; K. S. Pregitzer; D. R. Zak; M. E. Kubiske; W. E. Holmes

    2001-01-01

    Rising atmospheric carbon dioxide has the potential to alter leaf litter chemistry, potentially affecting decomposition and rates of carbon and nitrogen cycling in forest ecosystems. This study was conducted to determine whether growth under elevated atmospheric CO2 altered the quality and microbial decomposition of leaf litter of a widely...

  17. Nitrogen additions affect litter quality and soil biochemical properties in a peatland of Northeast China

    USGS Publications Warehouse

    Song, Yanyu; Song, Changchun; Meng, Henan; Swarzenski, Christopher M.; Wang, Xianwei; Tan, Wenwen

    2017-01-01

    Nitrogen (N) is a limiting nutrient in many peatland ecosystems. Enhanced N deposition, a major component of global climate change, affects ecosystem carbon (C) balance and alters soil C storage by changing plant and soil properties. However, the effects of enhanced N deposition on peatland ecosystems are poorly understood. We conducted a two-year N additions field experiment in a peatland dominated by Eriophorum vaginatum in the Da Xing’an Mountains, Northeast China. Four levels of N treatments were applied: (1) CK (no N added), (2) N1 (6 g N m−2 yr−1), (3) N2 (12 g N m−2 yr−1), and (4) N3 (24 g N m−2  yr−1). Plant and soil material was harvested at the end of the second growing season. N additions increased litter N and phosphorus (P) content, as well as β-glucosidase, invertase, and acid-phosphatase activity, but decreased litter C:N and C:P ratios. Litter carbon content remained unchanged. N additions increased available NH4+–N and NO3−–N as well as total Gram-positive (Gram+), Gram-negative (Gram−), and total bacterial phospholipid fatty acids (PLFA) in shallow soil (0–15 cm depth). An increase in these PLFAs was accompanied by a decrease in soil labile organic C (microbial biomass carbon and dissolved organic carbon), and appeared to accelerate decomposition and reduce the stability of the soil C pool. Invertase and urease activity in shallow soils and acid-phosphatase activity in deep soils (15–30 cm depth) was inhibited by N additions. Together, these findings suggest that an increase in N deposition in peatlands could accelerate litter decomposition and the loss of labile C, as well as alter microbial biomass and function.

  18. Tadpoles of Early Breeding Amphibians are Negatively Affected by Leaf Litter From Invasive Chinese Tallow Trees

    NASA Astrophysics Data System (ADS)

    Leonard, N. E.

    2005-05-01

    As wetlands are invaded by Chinese tallow trees (Triadica sebifera), native trees are displaced and detrital inputs to amphibian breeding ponds are altered. I used a mesocosm experiment to examine the effect of Chinese tallow leaf litter on the survival to, size at, and time to metamorphosis of amphibian larvae. Fifty 1000-L cattle watering tanks were treated with 1500 g dry weight of one of five leaf litter treatments: Chinese tallow, laurel oak (Quercus laurifolia), water tupelo (Nyssa aquatica), slash pine (Pinus elliottii), or a 3:1:1:1 mixture. Each tank received 45 tadpoles of Pseudacris feriarum, Bufo terrestris, and Hyla cinerea in sequence according to their natural breeding phonologies. Every Pseudacris feriarum and Bufo terrestris tadpole exposed to Chinese tallow died prior to metamorphosis. Hyla cinerea survival in tanks with tallow-only was significantly lower than that observed for all other leaf treatments. Hyla cinerea tadpoles from tallow-only and mixed-leaf treatments were larger at metamorphosis and transformed faster than those in tanks with native leaves only. These results suggest that Chinese tallow leaf litter may negatively affect tadpoles of early breeding frogs and that Chinese tallow invasion may change the structure of amphibian communities in temporary ponds.

  19. Early kit mortality and growth in farmed mink are affected by litter size rather than nest climate.

    PubMed

    Schou, T M; Malmkvist, J

    2017-09-01

    We investigated the effects of nest box climate on early mink kit mortality and growth. We hypothesised that litters in warm nest boxes experience less hypothermia-induced mortality and higher growth rates during the 1st week of life. This study included data from 749, 1-year-old breeding dams with access to nesting materials. Kits were weighed on days 1 and 7, dead kits were collected daily from birth until day 7 after birth, and nest climate was measured continuously from days 1 to 6. We tested the influences of the following daily temperature (T) and humidity (H) parameters on the number of live-born kit deaths and kit growth: T mean, T min, T max, T var (fluctuation) and H mean. The nest microclimate experienced by the kits was buffered against the ambient climate, with higher temperatures and reduced climate fluctuation. Most (77.0%) live-born kit deaths in the 1st week occurred on days 0 and 1. Seven of 15 climate parameters on days 1 to 3 had significant effects on live-born kit mortality. However, conflicting effects among days, marginal effects and late effects indicated that climate was not the primary cause of kit mortality. Five of 30 climate parameters had significant effects on kit growth. Few and conflicting effects indicated that the climate effect on growth was negligible. One exception was that large nest temperature fluctuations on day 1 were associated with reduced deaths of live-born kit (P<0.001) and increased kit growth (P=0.003). Litter size affected kit vitality; larger total litter size at birth was associated with greater risks of kit death (P<0.001) and reduced growth (P<0.001). The number of living kits in litters had the opposite effect, as kits in large liveborn litters had a reduced risk of death (P<0.001) and those with large mean litter size on days 1 to 7 had increased growth (P=0.026). Nest box temperature had little effect on early kit survival and growth, which could be due to dams' additional maternal behaviour. Therefore, we

  20. Mediterranean marine biodiversity under threat: Reviewing influence of marine litter on species.

    PubMed

    Deudero, Salud; Alomar, Carme

    2015-09-15

    The Mediterranean Sea is one of the most polluted seas worldwide, especially with regard to plastics. The presence of this emerging man made contaminant in marine environments precludes large effects and interactions with species exposed to massive litter quantities. In this review, available data of floating and seafloor litter around Mediterranean sub-basins are reported. A review of scientific literature on the interaction of plastic with marine biota resulted in the identification of 134 species, several taxa and feeding strategies affected from 1986 to 2014. Data from 17,334 individuals showed different levels of ingestion and effects on catalogued IUCN species (marine mammals and sea turtles) in addition to several pelagic fish and elasmobranchs. Biodiversity is certainly under threat, and knowledge of the extent of taxa affected is of concern considering the increasing plastic loads in the Mediterranean Sea and worldwide. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Differences in the sensitivity of fungi and bacteria to season and invertebrates affect leaf litter decomposition in a Mediterranean stream.

    PubMed

    Mora-Gómez, Juanita; Elosegi, Arturo; Duarte, Sofia; Cássio, Fernanda; Pascoal, Cláudia; Romaní, Anna M

    2016-08-01

    Microorganisms are key drivers of leaf litter decomposition; however, the mechanisms underlying the dynamics of different microbial groups are poorly understood. We investigated the effects of seasonal variation and invertebrates on fungal and bacterial dynamics, and on leaf litter decomposition. We followed the decomposition of Populus nigra litter in a Mediterranean stream through an annual cycle, using fine and coarse mesh bags. Irrespective of the season, microbial decomposition followed two stages. Initially, bacterial contribution to total microbial biomass was higher compared to later stages, and it was related to disaccharide and lignin degradation; in a later stage, bacteria were less important and were associated with hemicellulose and cellulose degradation, while fungi were related to lignin decomposition. The relevance of microbial groups in decomposition differed among seasons: fungi were more important in spring, whereas in summer, water quality changes seemed to favour bacteria and slowed down lignin and hemicellulose degradation. Invertebrates influenced litter-associated microbial assemblages (especially bacteria), stimulated enzyme efficiencies and reduced fungal biomass. We conclude that bacterial and fungal assemblages play distinctive roles in microbial decomposition and differ in their sensitivity to environmental changes, ultimately affecting litter decomposition, which might be particularly relevant in highly seasonal ecosystems, such as intermittent streams. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Effects of fire frequency on litter decomposition as mediated by changes to litter chemistry and soil environmental conditions

    PubMed Central

    Wright, Justin P.

    2017-01-01

    Litter quality and soil environmental conditions are well-studied drivers influencing decomposition rates, but the role played by disturbance legacy, such as fire history, in mediating these drivers is not well understood. Fire history may impact decomposition directly, through changes in soil conditions that impact microbial function, or indirectly, through shifts in plant community composition and litter chemistry. Here, we compared early-stage decomposition rates across longleaf pine forest blocks managed with varying fire frequencies (annual burns, triennial burns, fire-suppression). Using a reciprocal transplant design, we examined how litter chemistry and soil characteristics independently and jointly influenced litter decomposition. We found that both litter chemistry and soil environmental conditions influenced decomposition rates, but only the former was affected by historical fire frequency. Litter from annually burned sites had higher nitrogen content than litter from triennially burned and fire suppression sites, but this was correlated with only a modest increase in decomposition rates. Soil environmental conditions had a larger impact on decomposition than litter chemistry. Across the landscape, decomposition differed more along soil moisture gradients than across fire management regimes. These findings suggest that fire frequency has a limited effect on litter decomposition in this ecosystem, and encourage extending current decomposition frameworks into disturbed systems. However, litter from different species lost different masses due to fire, suggesting that fire may impact decomposition through the preferential combustion of some litter types. Overall, our findings also emphasize the important role of spatial variability in soil environmental conditions, which may be tied to fire frequency across large spatial scales, in driving decomposition rates in this system. PMID:29023560

  3. Leaf litter quality affects aquatic insect emergence: contrasting patterns from two foundation trees.

    PubMed

    Compson, Zacchaeus G; Adams, Kenneth J; Edwards, Joeseph A; Maestas, Jesse M; Whitham, Thomas G; Marks, Jane C

    2013-10-01

    Reciprocal subsidies between rivers and terrestrial habitats are common where terrestrial leaf litter provides energy to aquatic invertebrates while emerging aquatic insects provide energy to terrestrial predators (e.g., birds, lizards, spiders). We examined how aquatic insect emergence changed seasonally with litter from two foundation riparian trees, whose litter often dominates riparian streams of the southwestern United States: Fremont (Populus fremontii) and narrowleaf (Populus angustifolia) cottonwood. P. fremontii litter is fast-decomposing and lower in defensive phytochemicals (i.e., condensed tannins, lignin) relative to P. angustifolia. We experimentally manipulated leaf litter from these two species by placing them in leaf enclosures with emergence traps attached in order to determine how leaf type influenced insect emergence. Contrary to our initial predictions, we found that packs with slow-decomposing leaves tended to support more emergent insects relative to packs with fast-decomposing leaves. Three findings emerged. Firstly, abundance (number of emerging insects m(-2) day(-1)) was 25% higher on narrowleaf compared to Fremont leaves for the spring but did not differ in the fall, demonstrating that leaf quality from two dominant trees of the same genus yielded different emergence patterns and that these patterns changed seasonally. Secondly, functional feeding groups of emerging insects differed between treatments and seasons. Specifically, in the spring collector-gatherer abundance and biomass were higher on narrowleaf leaves, whereas collector-filterer abundance and biomass were higher on Fremont leaves. Shredder abundance and biomass were higher on narrowleaf leaves in the fall. Thirdly, diversity (Shannon's H') was higher on Fremont leaves in the spring, but no differences were found in the fall, showing that fast-decomposing leaves can support a more diverse, complex emergent insect assemblage during certain times of the year. Collectively, these

  4. Soil Fauna Affects Dissolved Carbon and Nitrogen in Foliar Litter in Alpine Forest and Alpine Meadow

    PubMed Central

    Liao, Shu; Yang, Wanqin; Tan, Yu; Peng, Yan; Li, Jun; Tan, Bo; Wu, Fuzhong

    2015-01-01

    Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) are generally considered important active biogeochemical pools of total carbon and nitrogen. Many studies have documented the contributions of soil fauna to litter decomposition, but the effects of the soil fauna on labile substances (i.e., DOC and TDN) in litter during early decomposition are not completely clear. Therefore, a field litterbag experiment was carried out from 13th November 2013 to 23rd October 2014 in an alpine forest and an alpine meadow located on the eastern Tibetan Plateau. Litterbags with different mesh sizes were used to provide access to or prohibit the access of the soil fauna, and the concentrations of DOC and TDN in the foliar litter were measured during the winter (the onset of freezing, deep freezing and thawing stage) and the growing season (early and late). After one year of field incubation, the concentration of DOC in the litter significantly decreased, whereas the TDN concentration in the litter increased. Similar dynamic patterns were detected under the effects of the soil fauna on both DOC and TDN in the litter between the alpine forest and the alpine meadow. The soil fauna showed greater positive effects on decreasing DOC concentration in the litter in the winter than in the growing season. In contrast, the dynamics of TND in the litter were related to seasonal changes in environmental factors, rather than the soil fauna. In addition, the soil fauna promoted a decrease in litter DOC/TDN ratio in both the alpine forest and the alpine meadow throughout the first year of decomposition, except for in the late growing season. These results suggest that the soil fauna can promote decreases in DOC and TDN concentrations in litter, contributing to early litter decomposition in these cold biomes. PMID:26406249

  5. Soil Fauna Affects Dissolved Carbon and Nitrogen in Foliar Litter in Alpine Forest and Alpine Meadow.

    PubMed

    Liao, Shu; Yang, Wanqin; Tan, Yu; Peng, Yan; Li, Jun; Tan, Bo; Wu, Fuzhong

    2015-01-01

    Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) are generally considered important active biogeochemical pools of total carbon and nitrogen. Many studies have documented the contributions of soil fauna to litter decomposition, but the effects of the soil fauna on labile substances (i.e., DOC and TDN) in litter during early decomposition are not completely clear. Therefore, a field litterbag experiment was carried out from 13th November 2013 to 23rd October 2014 in an alpine forest and an alpine meadow located on the eastern Tibetan Plateau. Litterbags with different mesh sizes were used to provide access to or prohibit the access of the soil fauna, and the concentrations of DOC and TDN in the foliar litter were measured during the winter (the onset of freezing, deep freezing and thawing stage) and the growing season (early and late). After one year of field incubation, the concentration of DOC in the litter significantly decreased, whereas the TDN concentration in the litter increased. Similar dynamic patterns were detected under the effects of the soil fauna on both DOC and TDN in the litter between the alpine forest and the alpine meadow. The soil fauna showed greater positive effects on decreasing DOC concentration in the litter in the winter than in the growing season. In contrast, the dynamics of TND in the litter were related to seasonal changes in environmental factors, rather than the soil fauna. In addition, the soil fauna promoted a decrease in litter DOC/TDN ratio in both the alpine forest and the alpine meadow throughout the first year of decomposition, except for in the late growing season. These results suggest that the soil fauna can promote decreases in DOC and TDN concentrations in litter, contributing to early litter decomposition in these cold biomes.

  6. The influence of litter quality and micro-habitat on litter decomposition and soil properties in a silvopasture system

    NASA Astrophysics Data System (ADS)

    Tripathi, G.; Deora, R.; Singh, G.

    2013-07-01

    Studies to understand litter processes and soil properties are useful for maintaining pastureland productivity as animal husbandry is the dominant occupation in the hot arid region. We aimed to quantify how micro-habitats and combinations of litters of the introduced leguminous tree Colophospermum mopane with the grasses Cenchrus ciliaris or Lasiurus sindicus influence decomposition rate and soil nutrient changes in a hot desert silvopasture system. Litter bags with tree litter alone (T), tree + C. ciliaris in 1:1 ratio (TCC) and tree + L. sindicus 1:1 ratio (TLS) litter were placed inside and outside of the C. mopane canopy and at the surface, 3-7 cm and 8-12 cm soil depths. We examined litter loss, soil fauna abundance, organic carbon (SOC), total (TN), ammonium (NH4-N) and nitrate (NO3-N) nitrogen, phosphorus (PO4-P), soil respiration (SR) and dehydrogenase activity (DHA) in soil adjacent to each litter bag. After 12 months exposure, the mean residual litter was 40.2% of the initial value and annual decomposition rate constant (k) was 0.98 (0.49-1.80). Highest (p < 0.01) litter loss was in the first four months, when faunal abundance, SR, DHA and humidity were highest but it decreased with time. These variables and k were highest under the tree canopies. The litter loss and k were highest (p < 0.01) in TLS under the tree canopy, but the reverse trend was found for litter outside the canopy. Faunal abundance, litter loss, k, nutrient release and biochemical activities were highest (p < 0.01) in the 3-7 cm soil layer. Positive correlations of litter loss and soil fauna abundance with soil nutrients, SR and DHA demonstrated the interactions of litter quality and micro-habitats together with soil fauna on increased soil fertility. These results suggest that a Colophospermum mopane and L. sindicus silvopasture system best promotes faunal abundance, litter decomposition and soil fertility. The properties of these species and the associated faunal resources may be

  7. Influence of in-house composting of reused litter on litter quality, ammonia volatilisation and incidence of broiler foot pad dermatitis.

    PubMed

    Martins, R S; Hötzel, M J; Poletto, R

    2013-01-01

    1. The objectives of this study were to evaluate the residual effects of two windrow composting methods for reused litter on its quality (pH, moisture, ammonia), ammonia (NH3) volatilisation and the prevalence (scores 0-4) of foot pad dermatitis (FPD) and hock burn (HB) on d 1, 7, 14 and 21 of age in broilers. Litter was allowed to compost for 8 d within a 14-d interval between flocks. 2. The composting methods studied were with or without a PVC plastic sheet. The same procedures were applied for three consecutive flocks, with litter initially having been used for 12 flocks. Data were analysed with a mixed model of repeated measures of day, with main effects and interactions of day, composting method, litter age (block) and house nested within method. 3. At d 1, litter NH3 and NH3 volatilisation were higher in the covered litter method. Litter moisture increased to 45.3% as broilers aged. The incidence of FPD also increased with age. No signs of HB were found in any bird throughout the trials. 4. There was no effect of litter composting methods on the prevalence of FPD or body weight at any age. 5. Litter moisture should be controlled to avoid NH3 volatilisation reaching critical levels. Windrow composting of litter with a PVC plastic sheet may not be required when considering the broiler housing environment.

  8. Fate of tannins in Corsican pine litter.

    PubMed

    Nierop, Klaas G J; Verstraten, Jacobus M

    2006-12-01

    Tannins are ubiquitous in higher plants and also in litter and soils where they affect many biogeochemical processes. Despite this well-recognized role, their fate in litter and mineral soils is hardly known, as often only trace amounts, if any, are measured. In this study, we conducted an incubation experiment with Corsican pine litter to which known amounts of tannic acid (TA) or condensed tannins (CTs) from Corsican pine were added. Using Folin-Ciocalteu as a measure for total phenolics and HCl-butanol as an assay specific for CTs, acetone/water extractable phenolics and tannins decreased with time towards very low levels. Application of thermally assisted hydrolysis and methylation to litter before and after acetone/water extraction revealed that TA concentration decreased. By contrast, CTs remained to a great extent in the litter and could not be extracted suggesting that they were tightly bound.

  9. Effects of dietary coarsely ground corn and litter type on broiler live performance, litter characteristics, gastrointestinal tract development, apparent ileal digestibility of energy and nitrogen, and intestinal morphology.

    PubMed

    Xu, Y; Stark, C R; Ferket, P R; Williams, C M; Auttawong, S; Brake, J

    2015-03-01

    The objectives of this study were to evaluate the effects of the dietary inclusion of 2 coarsely ground corn (CC) levels (0 or 50%) in diets of broilers reared on 2 litter types (new wood shavings or used litter) on live performance, litter characteristics, gastrointestinal tract (GIT) development, apparent ileal digestibility (AID) of energy and nitrogen (N), and intestinal morphology. No interaction effects between CC level and litter type were observed on live performance. No litter effect was observed on live performance. Dietary inclusion of 50% CC increased BW at 35 d (P<0.01) and improved cumulative feed conversion ratio (FCR) at 35 and 49 d of age (P<0.01). The 50% CC treatment increased absolute and relative gizzard weight (P<0.01) and decreased jejunum unit weight (g/cm) (P<0.01). The new litter treatment (litter N) increased absolute and relative proventriculus weight (P<0.05) but did not affect gizzard weight. An interaction effect between CC level and litter type was observed for litter N, where the 50% CC treatment reduced litter N regardless of litter type (P<0.01), but litter N was reduced by new litter only among birds fed 0% CC (P<0.05). The 50% CC inclusion increased litter pH (P<0.05) and improved the AID of energy and N by 6.8% (P<0.01) and 3.5% (P<0.05), respectively. The 50% CC treatment increased jejunum villi tip width (P<0.05) and villi surface area (P<0.01), and decreased the muscularis layer thickness (P<0.01), whereas new litter increased jejunum villi and ileum villi height (P<0.05), jejunum villi surface area (P<0.01), and the ratio of jejunum villi height to crypt depth (P<0.01). This study showed that birds fed pelleted and screened diets containing 50% CC exhibited improved BW, FCR, and AID of energy and N, in conjunction with altered morphology of the GIT and intestinal mucosa. Litter type affected some GIT traits and functions but did not affect live performance. © 2015 Poultry Science Association Inc.

  10. How interacting fungal species and mineral nitrogen inputs affect transfer of nitrogen from litter via arbuscular mycorrhizal mycelium.

    PubMed

    He, Yuejun; Cornelissen, J Hans C; Zhong, Zhangcheng; Dong, Ming; Jiang, Changhong

    2017-04-01

    In the karst landscape, widespread in the world including southern China, soil nutrient supply is strongly constrained. In such environments, arbuscular mycorrhizal (AM) fungi may facilitate plant nutrient uptake. However, the possible role of different AM fungal species, and their interactions, especially in transferring nitrogen (N) from litter to plant, is poorly understood. We conducted two microcosm experiments to investigate the role that two karst soil AM fungi, Glomus etunicatum and Glomus mosseae, play in the transfer of N from decomposing litter to the host plant and to determine how N availability influences these processes. In experiment 1, Cinnamomum camphora tree seedlings were grown in compartments inoculated with G. etunicatum. Lolium perenne leaf litter labeled with δ 15 N was added to the soil in unplanted compartments. Compartments containing the δ 15 N labeled litter were either accessible to hyphae but not to seedling roots or were not accessible to hyphae or roots. The addition of mineral N to one of the host compartments at the start of the experiment significantly increased the biomass of the C. camphora seedlings, N content and N:P ratio, AM mycelium length, and soil microbial biomass carbon and N. However, significantly, more δ 15 N was acquired, from the leaf litter by the AM hyphae and transferred to the host when mineral N was not added to the soil. In experiment 2, in which C. camphora seedlings were inoculated with both G. etunicatum and G. mosseae rather than with G. mosseae alone, there was a significant increase in mycelial growth (50.21%), in soil microbial biomass carbon (417.73%) in the rhizosphere, and in the amount of δ 15 N that was transferred to the host. These findings suggest that maintaining AM fungal diversity in karst soils could be important for mediating N transfer from organic material to host plants in N-poor soils.

  11. Factors affecting the abundance of leaf-litter arthropods in unburned and thrice-burned seasonally-dry Amazonian forests.

    PubMed

    Silveira, Juliana M; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-09-21

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance.

  12. Factors Affecting the Abundance of Leaf-Litter Arthropods in Unburned and Thrice-Burned Seasonally-Dry Amazonian Forests

    PubMed Central

    Silveira, Juliana M.; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance. PMID:20877720

  13. Association between litterers' profile and littering behavior: A chi-square approach

    NASA Astrophysics Data System (ADS)

    Asmui, Mas'udah; Zaki, Suhanom Mohd; Wahid, Sharifah Norhuda Syed; Mokhtar, Noorsuraya Mohd; Harith, Siti Suhaila

    2017-05-01

    Littering is not a novelty, yet a prolonged issue. The solutions have been discussed for a long time; however this issue still remains unresolved. Littering is commonly associated with littering behavior and awareness. The littering behavior is normally influenced by the litter profile such as gender, family income, education level and age. Jengka Street market, which is located in Pahang, is popularly known as a trade market. It offers diversities of wet and dry goods and is awaited by local residents and tourists. This study analyzes association between litterers' profile and littering behavior. Littering behavior is measured based on factors of trash bin facilities, awareness campaign and public littering behavior. 114 respondents were involved in this study with 62 (54.39%) are female aged more than 18 years old and majority of these female respondents are diploma holders. In addition, 78.95% of the respondents have family income below than RM3,000.00 per month. Based on the data analysis, it was found that first-time visitors littered higher than frequent visitors, lack of providing trash bin facilities contributes to positive littering behavior and there is a significant association between litterers' age and littering behavior by using chi-square approach.

  14. Measurement of broiler litter production rates and nutrient content using recycled litter.

    PubMed

    Coufal, C D; Chavez, C; Niemeyer, P R; Carey, J B

    2006-03-01

    It is important for broiler producers to know litter production rates and litter nutrient content when developing nutrient management plans. Estimation of broiler litter production varies widely in the literature due to factors such as geographical region, type of housing, size of broiler produced, and number of flocks reared on the same litter. Published data for N, P, and K content are also highly variable. In addition, few data are available regarding the rate of production, characteristics, and nutrient content of caked litter (cake). In this study, 18 consecutive flocks of broilers were reared on the same litter in experimental pens under simulated commercial conditions. The mass of litter and cake produced was measured after each flock. Samples of all litter materials were analyzed for pH, moisture, N, P, and K. Average litter and cake moisture content were 26.4 and 46.9%, respectively. Significant variation in litter and cake nutrient content was observed and can largely be attributed to ambient temperature differences. Average litter, cake, and total litter (litter plus cake) production rates were 153.3, 74.8, and 228.2 g of dry litter material per kg of live broiler weight (g/kg) per flock, respectively. Significant variation in litter production rates among flocks was also observed. Cumulative litter, cake, and total litter production rates after 18 flocks were 170.3, 78.7, and 249.0 g/kg, respectively. The data produced from this research can be used by broiler producers to estimate broiler litter and cake production and the nutrient content of these materials.

  15. Occurrence and sorption of fluoroquinolones in poultry litters and soils from São Paulo State, Brazil.

    PubMed

    Leal, Rafael Marques Pereira; Figueira, Rafael Fernandes; Tornisielo, Valdemar Luiz; Regitano, Jussara Borges

    2012-08-15

    Animal production is one of the most expressive sectors of Brazilian agro-economy. Although antibiotics are routinely used in this activity, their occurrence, fate, and potential impacts to the local environment are largely unknown. This research evaluated sorption-desorption and occurrence of four commonly used fluoroquinolones (norfloxacin, ciprofloxacin, danofloxacin, and enrofloxacin) in poultry litter and soil samples from São Paulo State, Brazil. The sorption-desorption studies involved batch equilibration technique and followed the OECD guideline for pesticides. All compounds were analyzed by HPLC, using fluorescence detector. Fluoroquinolones' sorption potential to the poultry litters (K(d) ≤65 L kg(-1)) was lower than to the soil (K(d) ~40,000 L kg(-1)), but was always high (≥69% of applied amount) indicating a higher specificity of fluoroquinolones interaction with soils. The addition of poultry litter (5%) to the soil had not affected sorption or desorption of these compounds. Desorption was negligible in the soil (≤0.5% of sorbed amount), but not in the poultry litters (up to 42% of sorbed amount). Fluoroquinolones' mean concentrations found in the poultry litters (1.37 to 6.68 mg kg(-1)) and soils (22.93 μg kg(-1)) were compatible to those found elsewhere (Austria, China, and Turkey). Enrofloxacin was the most often detected compound (30% of poultry litters and 27% of soils) at the highest mean concentrations (6.68 mg kg(-1) for poultry litters and 22.93 μg kg(-1) for soils). These results show that antibiotics are routinely used in poultry production and might represent one potential source of pollution to the environment that has been largely ignored and should be further investigated in Brazil. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Interaction between loggerhead sea turtles (Caretta caretta) and marine litter in Sardinia (Western Mediterranean Sea).

    PubMed

    Camedda, Andrea; Marra, Stefano; Matiddi, Marco; Massaro, Giorgio; Coppa, Stefania; Perilli, Angelo; Ruiu, Angelo; Briguglio, Paolo; de Lucia, G Andrea

    2014-09-01

    Anthropogenic debris in the environment affects many species that accidentally ingest it. The aim of this study is to evaluate the quantity and composition of marine litter ingested by loggerheads in Sardinia, thus supplying for the lack of data in the existing literature for this area. Seventeen of the 121 (14.04%) monitored turtles presented debris in their digestive tracts. Litter in faecal pellet of alive individuals (n = 91) and in gastro-intestinal contents of dead ones (n = 30) was categorized, counted and weighed. User plastic was the main category of ingested debris with a frequency of occurrence of 13.22% of the total sample, while sheet (12.39%) and fragments (9.09%) were the most relevant sub-categories. This study highlights for the first time the incidence of litter in alive turtles in Sardinia. This contribution improves the knowledge about marine litter interaction on Caretta caretta as bio-indicator. Results will be useful for the Marine Strategy implementation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Forest composition modifies litter dynamics and decomposition in regenerating tropical dry forest.

    PubMed

    Schilling, Erik M; Waring, Bonnie G; Schilling, Jonathan S; Powers, Jennifer S

    2016-09-01

    We investigated how forest composition, litter quality, and rainfall interact to affect leaf litter decomposition across three successional tropical dry forests in Costa Rica. We monitored litter stocks and bulk litter turnover in 18 plots that exhibit substantial variation in soil characteristics, tree community structure, fungal communities (including forests dominated by ecto- or arbuscular mycorrhizal host trees), and forest age. Simultaneously, we decomposed three standard litter substrates over a 6-month period spanning an unusually intense drought. Decay rates of standard substrates depended on the interaction between litter identity and forest type. Decomposition rates were correlated with tree and soil fungal community composition as well as soil fertility, but these relationships differed among litter types. In low fertility soils dominated by ectomycorrhizal oak trees, bulk litter turnover rates were low, regardless of soil moisture. By contrast, in higher fertility soils that supported mostly arbuscular mycorrhizal trees, bulk litter decay rates were strongly dependent on seasonal water availability. Both measures of decomposition increased with forest age, as did the frequency of termite-mediated wood decay. Taken together, our results demonstrate that soils and forest age exert strong control over decomposition dynamics in these tropical dry forests, either directly through effects on microclimate and nutrients, or indirectly by affecting tree and microbial community composition and traits, such as litter quality.

  18. Litter-Spinning Retarders

    NASA Technical Reports Server (NTRS)

    Wilson, John C.

    1995-01-01

    Aerodynamic plates stop litter from spinning during hoisting by helicopter. Features of proposed litter-spinning retarders include convenience of deployment and independence from ground restraint. Retarder plate(s) folded flat against bottom of litter during storage or while litter is loaded. Plate(s) held in storage position by latch that releases manually or automatically as litter is hoisted. Upon release, springs move plates into deployed position.

  19. Functionally dissimilar neighbors accelerate litter decomposition in two grass species.

    PubMed

    Barbe, Lou; Jung, Vincent; Prinzing, Andreas; Bittebiere, Anne-Kristel; Butenschoen, Olaf; Mony, Cendrine

    2017-05-01

    Plant litter decomposition is a key regulator of nutrient recycling. In a given environment, decomposition of litter from a focal species depends on its litter quality and on the efficiency of local decomposers. Both may be strongly modified by functional traits of neighboring species, but the consequences for decomposition of litter from the focal species remain unknown. We tested whether decomposition of a focal plant's litter is influenced by the functional-trait dissimilarity to the neighboring plants. We cultivated two grass species (Brachypodium pinnatum and Elytrigia repens) in experimental mesocosms with functionally similar and dissimilar neighborhoods, and reciprocally transplanted litter. For both species, litter quality increased in functionally dissimilar neighborhoods, partly as a result of changes in functional traits involved in plant-plant interactions. Furthermore, functional dissimilarity increased overall decomposer efficiency in one species, probably via complementarity effects. Our results suggest a novel mechanism of biodiversity effects on ecosystem functioning in grasslands: interspecific functional diversity within plant communities can enhance intraspecific contributions to litter decomposition. Thus, plant species might better perform in diverse communities by benefiting from higher remineralization rates of their own litter. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  20. Succession of Phylogeny and Function During Plant Litter Decomposition (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

    ScienceCinema

    Brodie, Eoin

    2018-04-26

    Eoin Brodie of Berkeley Lab on "Succession of phylogeny and function during plant litter decomposition" at the 8th Annual Genomics of Energy & Environment Meeting on March 27, 2013 in Walnut Creek, CA.

  1. Succession of Phylogeny and Function During Plant Litter Decomposition (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brodie, Eoin

    2013-03-01

    Eoin Brodie of Berkeley Lab on "Succession of phylogeny and function during plant litter decomposition" at the 8th Annual Genomics of Energy & Environment Meeting on March 27, 2013 in Walnut Creek, CA.

  2. Foliar litter decomposition in an alpine forest meta-ecosystem on the eastern Tibetan Plateau.

    PubMed

    Yue, Kai; Yang, Wanqin; Peng, Changhui; Peng, Yan; Zhang, Chuan; Huang, Chunping; Tan, Yu; Wu, Fuzhong

    2016-10-01

    Litter decomposition is a biological process fundamental to element cycling and a main nutrient source within forest meta-ecosystems, but few studies have looked into this process simultaneously in individual ecosystems, where environmental factors can vary substantially. A two-year field study conducted in an alpine forest meta-ecosystem with four litter species (i.e., willow: Salix paraplesia, azalea: Rhododendron lapponicum, cypress: Sabina saltuaria, and larch: Larix mastersiana) that varied widely in chemical traits showed that both litter species and ecosystem type (i.e., forest floor, stream and riparian zone) are important factors affecting litter decomposition, and their effects can be moderated by local-scale environmental factors such as temperature and nutrient availability. Litter decomposed fastest in the streams followed by the riparian zone and forest floor regardless of species. For a given litter species, both the k value and limit value varied significantly among ecosystems, indicating that the litter decomposition rate and extent (i.e., reaching a limit value) can be substantially affected by ecosystem type and the local-scale environmental factors. Apart from litter initial acid unhydrolyzable residue (AUR) concentration and its ratio to nitrogen concentration (i.e., AUR/N ratio), the initial nutrient concentrations of phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) were also important litter traits that affected decomposition depending on the ecosystem type. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Influence of waste management policy on the characteristics of beach litter in Kaohsiung, Taiwan.

    PubMed

    Liu, Ta-Kang; Wang, Meng-Wei; Chen, Ping

    2013-07-15

    Marine debris is a ubiquitous problem that poses a serious threat to the global oceans; it has motivated public participation in clean-up campaigns, as well as governmental involvement in developing mitigation strategies. While it is known that the problem of marine litter may be affected by waste management practices on land, beach survey results have seldom been compared with them. In this study, marine litter surveys on four beaches of Cijin Island were conducted to explore the effects of waste management and policy implications. Indirect evidence shows that chances for land-based litter, such as plastic bags and bottles, entering the marine environment can be greatly decreased if they can be properly reduced, reused and recycled. We suggest that mitigation measures should focus on source reduction, waste recycling and management, utilizing effective economic instruments, and pursuing a long-term public education campaign to raise the public awareness of this problem. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Distribution of beach litter along the coastline of Cádiz, Spain.

    PubMed

    Williams, Allan Thomas; Randerson, Peter; Di Giacomo, Carlo; Anfuso, Giorgio; Macias, Ana; Perales, José Antonio

    2016-06-15

    A total of 59 categories of litter items were found at 20 beaches (13 mechanically cleaned, 7 non-cleaned) in the Cádiz tourist environment, Spain. Cluster Analysis and Principal Components Analysis were used to highlight similarities and contrasts between sites and/or associations between litter categories. Multivariate analyses separated beaches according to the total numbers of litter items present. Non-cleaned sites showed a variety of litter category abundance with distinct origins and abundant, ubiquitous items (plastic and glass fragments). Of the 7 non-cleaned beaches (49 litter categories) river-mouth sites were distinct due with high numbers of litter items. The sheltered inner part of Cádiz Bay beaches had a wide range of litter type. Many sites were associated with locally deposited recreational litter categories; while industrial/commercial/fishing categories were abundant only at a few sites, indicating items transported onto the shore from the Guadalete river. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Stoichiometry and climatic stress drive respiration and nutrient dynamics of beech litter decomposition

    NASA Astrophysics Data System (ADS)

    Keiblinger, Katharina Maria; Hämmerle, Ieda; Zechmeister-Boltenstern, Sophie

    2010-05-01

    Little is known about how the variance in resources in terms of carbon (C), nitrogen (N), phosphorus (P) ratios affects respiration and nutrient dynamics. To elucidate how resource quantity and stoichiometry affect the decomposition process of beech (Fagus sylvatica) litter a terrestrial microcosm experiment was conducted. Our aim was to follow changes of beech litter stoichiometry and biogeochemical processes, and to quantify element losses as affected by temperature and moisture extremes. In addition to gaseous element losses (CO2) we examined the release of nutrients prone to leaching and the importance of environmental controls. We addressed mechanisms and pathways of carbon, nitrogen and phosphorus losses. In our experiment sterilised dried leaves were inoculated with a litter-soil suspension from a beech forest in order to ensure similar starting conditions. Beech litter from different Austrian sites covering C:N ratios from 45 to 66 and C:P ratios from 652 to 1467 were incubated at 15°C for six months. The water content was adjusted to 60% at regular intervals to keep the moisture constant. To monitor transient and persistent influences of environmental stress, the microcosms were subject to extreme changes in temperature (+30°C and -20°C) and moisture (draught) after an incubation time of three months. Litter stoichiometries (C:N, C:P) turned out to be strong predictors for respiration, and nitrogen, and phosphorous losses. (i) Litter with narrow litter C:nutrient ratios decomposed faster than litter with wider litter C:nutrient ratios; and therefore showed higher respiration rates. (ii) Increased nutrient losses as leachates were observed for high quality leaf litter i.e. inorganic nitrogen losses for sites with narrow litter C:N ratios and phosphate was released more quickly in sites with narrow C:P ratios. There was a strong functional response of the microbial community to environmental extremes. Respiration increased upon temperature extremes

  6. Highly reduced mass loss rates and increased litter layer in radioactively contaminated areas.

    PubMed

    Mousseau, Timothy A; Milinevsky, Gennadi; Kenney-Hunt, Jane; Møller, Anders Pape

    2014-05-01

    The effects of radioactive contamination from Chernobyl on decomposition of plant material still remain unknown. We predicted that decomposition rate would be reduced in the most contaminated sites due to an absence or reduced densities of soil invertebrates. If microorganisms were the main agents responsible for decomposition, exclusion of large soil invertebrates should not affect decomposition. In September 2007 we deposited 572 bags with uncontaminated dry leaf litter from four species of trees in the leaf litter layer at 20 forest sites around Chernobyl that varied in background radiation by more than a factor 2,600. Approximately one quarter of these bags were made of a fine mesh that prevented access to litter by soil invertebrates. These bags were retrieved in June 2008, dried and weighed to estimate litter mass loss. Litter mass loss was 40% lower in the most contaminated sites relative to sites with a normal background radiation level for Ukraine. Similar reductions in litter mass loss were estimated for individual litter bags, litter bags at different sites, and differences between litter bags at pairs of neighboring sites differing in level of radioactive contamination. Litter mass loss was slightly greater in the presence of large soil invertebrates than in their absence. The thickness of the forest floor increased with the level of radiation and decreased with proportional loss of mass from all litter bags. These findings suggest that radioactive contamination has reduced the rate of litter mass loss, increased accumulation of litter, and affected growth conditions for plants.

  7. Mixing effects on litter decomposition rates in a young tree diversity experiment

    NASA Astrophysics Data System (ADS)

    Setiawan, Nuri Nurlaila; Vanhellemont, Margot; De Schrijver, An; Schelfhout, Stephanie; Baeten, Lander; Verheyen, Kris

    2016-01-01

    Litter decomposition is an essential process for biogeochemical cycling and for the formation of new soil organic matter. Mixing litter from different tree species has been reported to increase litter decomposition rates through synergistic effects. We assessed the decomposition rates of leaf litter from five tree species in a recently established tree diversity experiment on a post-agriculture site in Belgium. We used 20 different leaf litter compositions with diversity levels ranging from 1 up to 4 species. Litter mass loss in litterbags was assessed 10, 20, 25, 35, and 60 weeks after installation in the field. We found that litter decomposition rates were higher for high-quality litters, i.e., with high nitrogen content and low lignin content. The decomposition rates of mixed litter were more affected by the identity of the litter species within the mixture than by the diversity of the litter per se, but the variability in litter decomposition rates decreased as the litter diversity increased. Among the 15 different mixed litter compositions in our study, only three litter combinations showed synergistic effects. Our study suggests that admixing tree species with high-quality litter in post-agricultural plantations helps in increasing the mixture's early-stage litter decomposition rate.

  8. Public perspective towards marine litter in West Aceh City

    NASA Astrophysics Data System (ADS)

    Kusumawati, I.; Setyowati, M.; Riana, E.; Prartono, T.

    2018-03-01

    Marine litter or marine debris is a man-made solid material discarded, abandoned or lost in coastline or into the sea. To reduce the amount of marine litter in the ocean, raising public awareness is an important way. One of the contributing factors on marine litter is the lack of understanding within the community, but to identify how people notice the problem is required adequate research literature. The purpose of this study is to examine the awareness of West Aceh community on marine litter along western coastal area. The research objectives; 1) to evaluate societal perception towards marine litter; 2) to examine the urgent indicator of public awareness in West Aceh City. This study will employ a survey approach by distributing questionnaires to 383 respondents. It was found that respondents show low awareness on marine litter according to statistical data, but there are some rooms to manage in order to raise the level of public awareness. It concludes that sense of responsibility could be enhanced by involving public in any activities for preventing and eradicating marine litter. Education aspect is also important to increase public understanding about the threats of marine debris on environment, human health and economic income.

  9. Effects of anthropogenic heavy metal contamination on litter decomposition in streams - A meta-analysis.

    PubMed

    Ferreira, Verónica; Koricheva, Julia; Duarte, Sofia; Niyogi, Dev K; Guérold, François

    2016-03-01

    Many streams worldwide are affected by heavy metal contamination, mostly due to past and present mining activities. Here we present a meta-analysis of 38 studies (reporting 133 cases) published between 1978 and 2014 that reported the effects of heavy metal contamination on the decomposition of terrestrial litter in running waters. Overall, heavy metal contamination significantly inhibited litter decomposition. The effect was stronger for laboratory than for field studies, likely due to better control of confounding variables in the former, antagonistic interactions between metals and other environmental variables in the latter or differences in metal identity and concentration between studies. For laboratory studies, only copper + zinc mixtures significantly inhibited litter decomposition, while no significant effects were found for silver, aluminum, cadmium or zinc considered individually. For field studies, coal and metal mine drainage strongly inhibited litter decomposition, while drainage from motorways had no significant effects. The effect of coal mine drainage did not depend on drainage pH. Coal mine drainage negatively affected leaf litter decomposition independently of leaf litter identity; no significant effect was found for wood decomposition, but sample size was low. Considering metal mine drainage, arsenic mines had a stronger negative effect on leaf litter decomposition than gold or pyrite mines. Metal mine drainage significantly inhibited leaf litter decomposition driven by both microbes and invertebrates, independently of leaf litter identity; no significant effect was found for microbially driven decomposition, but sample size was low. Overall, mine drainage negatively affects leaf litter decomposition, likely through negative effects on invertebrates. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Abundance of litter on Condor seamount (Azores, Portugal, Northeast Atlantic)

    NASA Astrophysics Data System (ADS)

    Pham, C. K.; Gomes-Pereira, J. N.; Isidro, E. J.; Santos, R. S.; Morato, T.

    2013-12-01

    Marine litter is an emerging problem for the world's ocean health but little is known on its distribution and abundance on seamounts and how it affects deep-sea ecosystems. The scientific underwater laboratory set up on Condor seamount offered an ideal case study for the first documentation of litter distribution on a shallow seamount with historical fishing. A total of 48 video transects deployed on the summit (n=45) and the northern flank (n=3) covered an area of 0.031 and 0.025km2, respectively, revealing 55 litter items. Litter density on the summit was 1439 litter items km-2, whilst on the deeper northern flank, estimates indicate densities of 397 litter items km-2. Lost fishing line was the dominant litter item encountered on both areas (73% of total litter on the summit and 50% on northern flank), all being entirely or partly entangled in the locally abundant gorgonians Dentomuricea cf. meteor and Viminella flagellum. Other items included lost weights, anchors and glass bottles. The predominance of lost fishing gear identifies the source of litter on Condor seamount as exclusively ocean-based and related to fishing activities. Abundance of litter on the Condor seamount was much lower than that reported from other locations closer to populated areas.

  11. Reciprocal Effects of Litter from Exotic and Congeneric Native Plant Species via Soil Nutrients

    PubMed Central

    Meisner, Annelein; de Boer, Wietse; Cornelissen, Johannes H. C.; van der Putten, Wim H.

    2012-01-01

    Invasive exotic plant species are often expected to benefit exclusively from legacy effects of their litter inputs on soil processes and nutrient availability. However, there are relatively few experimental tests determining how litter of exotic plants affects their own growth conditions compared to congeneric native plant species. Here, we test how the legacy of litter from three exotic plant species affects their own performance in comparison to their congeneric natives that co-occur in the invaded habitat. We also analyzed litter effects on soil processes. In all three comparisons, soil with litter from exotic plant species had the highest respiration rates. In two out of the three exotic-native species comparisons, soil with litter from exotic plant species had higher inorganic nitrogen concentrations than their native congener, which was likely due to higher initial litter quality of the exotics. When litter from an exotic plant species had a positive effect on itself, it also had a positive effect on its native congener. We conclude that exotic plant species develop a legacy effect in soil from the invaded range through their litter inputs. This litter legacy effect results in altered soil processes that can promote both the exotic plant species and their native congener. PMID:22359604

  12. Role of litter decomposition sensitivity to water content in non-additive litter mixture effect: theoretical demonstration and validation with a peatland litter experiment

    NASA Astrophysics Data System (ADS)

    Gogo, Sébastien; Leroy, Fabien; Zoccatelli, Renata; Bernard-Jannin, Léonard; Laggoun-Défarge, Fatima

    2017-04-01

    In this work, we showed theoretically that differences in litter water content, evaporation rate and reaction rate sensitivity to water content can give account of non-additive litter mixture effect. More specifically two litters with the same dependence to litter water content and contrasted water content, and 2 litters with contrasted decomposition sensitivity to litter water content can exert synergistic mixture effect on decomposition when the 2 litters interact. In these situations, water can flow from the wettest to the driest litter, changing the whole reaction rate without changing the whole litter water content. The reaction rate increase of the litter receiving the water was relatively more important than the reaction rate decrease of the litter supplying the water. These theoretical considerations were validated with experimental data. Sphagnum rubellum and Molinia caerulea decompose faster in measured mixture than expected from the rates obtained in monoculture incubation. Sphagnum rubellum litter can contain more water, which evaporates at a slower rate than Molinia caerulea. It is thus proposed that water flowed from Sphagnum rubellum litter to the Molinia caerulea litter, with a substantial increase of the decomposition of the latter. The physical and biochemical litter characteristics towards water explains a fraction of the synergistic effect of mixing the 2 litters, which suggests that other factors intervene in this effect, such as the carbon substrate.

  13. How do microlocal environmental variations affect microbial activities of a Pinus halepensis litter in a Mediterranean coastal area?

    PubMed

    Qasemian, Leila; Guiral, Daniel; Farnet, Anne-Marie

    2014-10-15

    Mediterranean coastal ecosystems suffer many different types of natural and anthropogenic environmental pressure. Microbial communities, major conductors of organic matter decomposition are also subject to these environmental constraints. In this study, our aim was to understand how microbial activities vary at a small spatio-temporal scale in a Mediterranean coastal environment. Microbial activities were monitored in a Pinus halepensis litter collected from two areas, one close to (10 m) and one far from (300 m) the French Mediterranean coast. Litters were transferred from one area to the other using litterbags and studied via different microbial indicators after 2, 5 and 13 months. Microbial Basal Respiration, qCO₂, certain enzyme activities (laccase, cellulase, β-glucosidase and acid phosphatase) and functional diversity via Biolog microplates were assayed in litterbags left in the area of origin as well as in litterbags transferred from one area to the other. Results highlight that microbial activities differ significantly in this short spatial scale over time. The influence of microlocal conditions more intensified for litters situated close to the sea, especially during summer seems to have a stressful effect on microbial communities, leading to less efficient functional activities. However, microbial activities were more strongly influenced by temporal variations linked to seasonality than by location. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Water addition, evaporation and water holding capacity of poultry litter.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2015-12-15

    Litter moisture content has been related to ammonia, dust and odour emissions as well as bird health and welfare. Improved understanding of the water holding properties of poultry litter as well as water additions to litter and evaporation from litter will contribute to improved litter moisture management during the meat chicken grow-out. The purpose of this paper is to demonstrate how management and environmental conditions over the course of a grow-out affect the volume of water A) applied to litter, B) able to be stored in litter, and C) evaporated from litter on a daily basis. The same unit of measurement has been used to enable direct comparison-litres of water per square metre of poultry shed floor area, L/m(2), assuming a litter depth of 5cm. An equation was developed to estimate the amount of water added to litter from bird excretion and drinking spillage, which are sources of regular water application to the litter. Using this equation showed that water applied to litter from these sources changes over the course of a grow-out, and can be as much as 3.2L/m(2)/day. Over a 56day grow-out, the total quantity of water added to the litter was estimated to be 104L/m(2). Litter porosity, water holding capacity and water evaporation rates from litter were measured experimentally. Litter porosity decreased and water holding capacity increased over the course of a grow-out due to manure addition. Water evaporation rates at 25°C and 50% relative humidity ranged from 0.5 to 10L/m(2)/day. Evaporation rates increased with litter moisture content and air speed. Maintaining dry litter at the peak of a grow-out is likely to be challenging because evaporation rates from dry litter may be insufficient to remove the quantity of water added to the litter on a daily basis. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  15. A multi-criteria evaluation system for marine litter pollution based on statistical analyses of OSPAR beach litter monitoring time series.

    PubMed

    Schulz, Marcus; Neumann, Daniel; Fleet, David M; Matthies, Michael

    2013-12-01

    During the last decades, marine pollution with anthropogenic litter has become a worldwide major environmental concern. Standardized monitoring of litter since 2001 on 78 beaches selected within the framework of the Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR) has been used to identify temporal trends of marine litter. Based on statistical analyses of this dataset a two-part multi-criteria evaluation system for beach litter pollution of the North-East Atlantic and the North Sea is proposed. Canonical correlation analyses, linear regression analyses, and non-parametric analyses of variance were used to identify different temporal trends. A classification of beaches was derived from cluster analyses and served to define different states of beach quality according to abundances of 17 input variables. The evaluation system is easily applicable and relies on the above-mentioned classification and on significant temporal trends implied by significant rank correlations. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. [Litter production and breakdown in swamps dominated by palms (Arecaceae) in northeastern Costa Rica].

    PubMed

    Myers, Ronald L

    2013-09-01

    In Raffia (Raphia taedigera) palm-swamps, it is frequent to observe high mounds at the base of the palm clumps. These mounds are formed by the accumulation of litter and organic matter, or might result from upturned roots of wind-thrown trees. The mounds serve as anchorage site for the palms, and could be important for the establishment of woody tree species in the swamp. The formation of these mounds might be explained by the unequal accumulation of organic matter in the wetland, or by differences in decomposition rates between Raffia litter versus the litter produced in adjacent mixed forests. To distinguish between these hypotheses, I compared the spatial distribution of litter in a R. taedigera swamp with the litter distribution on an adjacent slope forest, where litter distribution is expected to be homogeneous. In addition, I compared decomposition rates of major components of fine litter in three different environments: two wetlands dominated by palms (R. taedigera and Manicaria saccifera) and a slope forest that experiences lower inundation effects. On the palm swamp, noticeable concentration of litter was observed near the bases of clumps of palm as opposed to the swamp floor. In the adjacent slope forest, the magnitude of the differences in the distribution of litter is small and there is no accumulation at the base of emergent trees. It was also found that litter production increases during heavy rains and storms that follow dry periods. The swamp environment, independent of the litter, showed significantly lower decomposition rates than the surrounding forest slope. Furthermore, R. taedigera litter decomposes as fast as the slope forest litter. Overall, these results suggest that resistance to decomposition is not a major factor in the formation of mounds at the bases of R. taedigera clumps. Instead, litter accumulation contributes to the formation of the mounds that rise above the surface of the swamp.

  17. Microbiological and chemical properties of litter from different chicken types and production systems.

    PubMed

    Omeira, N; Barbour, E K; Nehme, P A; Hamadeh, S K; Zurayk, R; Bashour, I

    2006-08-15

    Chicken litter is produced in large quantities from all types of poultry raising activities. It is primarily used for land application, thus it is essential to analyze its properties before it is released to the environment. The objective of this study is to compare the microbiological and chemical properties of litter generated from layer and broiler chickens reared under intensive and free-range production systems. The microbiological analysis consisted of the enumeration of total bacteria, total coliforms, Staphylococcus species, Salmonella species and Clostridium perfringens. Chicken litter from layers reared under intensive and free range systems showed lower mean total bacterial count than the litter collected from chicken broilers reared under either of the two systems (P=0.0291). The litter from intensive layers had the lowest mean total coliform counts (P=0.0222) while the lowest Staphylococcus species count was observed in the litter from free-range layers (P=0.0077). The C. perfringens count was the lowest in chicken litter from intensively raised broilers and layers (P=0.0001). The chemical properties of litter from the different chicken types and production systems were compared based on determination of pH, electrical conductivity, carbon, nitrogen, phosphorus, potassium, cadmium and zinc. Litter from free-range broilers showed the highest pH value (P=0.0005); however, the electrical conductivity was higher in the litter from both intensive and free-range layers compared to the litter from both broiler production systems (P=0.0117). Chicken litter from intensive systems had higher nitrogen content than litter from free-range systems (P=0.0000). The total phosphorus was the lowest in free-range broiler litter (P=0.0001), while the total potassium was the lowest in litter from intensively managed broilers (P=0.0000). Zinc appeared higher in litter from layers compared to that from broilers (P=0.0101). The cadmium content was higher in the litter from

  18. Microbial communities may modify how litter quality affects potential decomposition rates as tree species migrate

    Treesearch

    Ashley D. Keiser; Jennifer D. Knoepp; Mark A. Bradford

    2013-01-01

    Background and aims Climate change alters regional plant species distributions, creating new combinations of litter species and soil communities. Biogeographic patterns in microbial communities relate to dissimilarity in microbial community function, meaning novel litters to communities may decompose differently than predicted from their chemical composition. Therefore...

  19. Flammability across the gymnosperm phylogeny: the importance of litter particle size.

    PubMed

    Cornwell, William K; Elvira, Alba; van Kempen, Lute; van Logtestijn, Richard S P; Aptroot, André; Cornelissen, J Hans C

    2015-04-01

    Fire is important to climate, element cycles and plant communities, with many fires spreading via surface litter. The influence of species on the spread of surface fire is mediated by their traits which, after senescence and abscission, have 'afterlife' effects on litter flammability. We hypothesized that differences in litter flammability among gymnosperms are determined by litter particle size effects on litterbed packing. We performed a mesocosm fire experiment comparing 39 phylogenetically wide-ranging gymnosperms, followed by litter size and shape manipulations on two chemically contrasting species, to isolate the underlying mechanism. The first-order control on litter flammability was, indeed, litter particle size in both experiments. Most gymnosperms were highly flammable, but a prominent exception was the non-Pinus Pinaceae, in which small leaves abscised singly produced dense, non-flammable litterbeds. There are two important implications: first, ecosystems dominated by gymnosperms that drop small leaves separately will develop dense litter layers, which will be less prone to and inhibit the spread of surface litter fire. Second, some of the needle-leaved species previously considered to be flammable in single-leaf experiments were among the least flammable in litter fuel beds, highlighting the role of the litter traits of species in affecting surface fire regimes. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  20. Covering their butts: responses to the cigarette litter problem.

    PubMed

    Smith, Elizabeth A; McDaniel, Patricia A

    2011-03-01

    Cigarette butt litter is a potential target of tobacco control. In addition to its toxicity and non-biodegradability, it can justify environmental regulation and policies that raise the price of tobacco and further denormalise its use. This paper examines how the tobacco industry has managed the cigarette butt litter issue and how the issue has been covered in the media. We searched the Legacy Tobacco Documents Library (http://legacy.library.ucsf.edu/) using a snowball strategy. We analysed data from approximately 700 documents, dated 1959-2006, using an interpretive approach. We also searched two newspaper databases, Lexis/Nexis and Newsbank, and found 406 relevant articles, dated 1982-2009 which we analysed quantitatively and qualitatively. The tobacco industry monitored and developed strategies for dealing with the cigarette litter issue because it affected the social acceptability of smoking, created the potential for alliances between tobacco control and environmental advocates, and created a target for regulation. The industry developed anti-litter programs with Keep America Beautiful (KAB) and similar organisations. Media coverage focused on industry-acceptable solutions, such as volunteer clean-ups and installation of ashtrays; stories that mentioned KAB were also more frequently positive towards the tobacco industry. Among alternative approaches, clean outdoor air (COA) laws received the most media attention. Cigarette litter, like secondhand smoke, is the result of smoker behaviour and affects nonsmokers. The tobacco industry has tried and failed to mitigate the impact of cigarette litter. Tobacco control advocates should explore alliances with environmental groups and propose policy options that hold the industry accountable for cigarette waste.

  1. Galling by Rhopalomyia solidaginis alters Solidago altissima architecture and litter nutrient dynamics in an old-field ecosystem

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crutsinger, Greg; Habenicht, Melissa N; Classen, Aimee T

    2008-01-01

    Plant-insect interactions can alter ecosystem processes, especially if the insects modify plant architecture, quality, or the quantity of leaf litter inputs. In this study, we investigated the interactions between the gall midge Rhopalomyia solidaginis and tall goldenrod, Solidago altissima, to quantify the degree to which the midge alters plant architecture and how the galls affect rates of litter decomposition and nutrient release in an old-field ecosystem. R. solidaginis commonly leads to the formation of a distinct apical rosette gall on S. altissima and approximately 15% of the ramets in a S. altissima patch were galled (range: 3-34%). Aboveground biomass ofmore » galled ramets was 60% higher and the leaf area density was four times greater on galled leaf tissue relative to the portions of the plant that were not affected by the gall. Overall decomposition rate constants did not differ between galled and ungalled leaf litter. However, leaf-litter mass loss was lower in galled litter relative to ungalled litter, which was likely driven by modest differences in initial litter chemistry; this effect diminished after 12 weeks of decomposition in the field. The proportion of N remaining was always higher in galled litter than in ungalled litter at each collection date indicating differential release of nitrogen in galled leaf litter. Several studies have shown that plant-insect interactions on woody species can alter ecosystem processes by affecting the quality or quantity of litter inputs. Our results illustrate how plant-insect interactions in an herbaceous species can affect ecosystem processes by altering the quality and quantity of litter inputs. Given that S. altissima dominates fields and roadsides and that R. solidaginis galls are highly abundant throughout eastern North America, these interactions are likely to be important for both the structure and function of old-field ecosystems.« less

  2. Direct and Indirect Effects of UV-B Exposure on Litter Decomposition: A Meta-Analysis

    PubMed Central

    Song, Xinzhang; Peng, Changhui; Jiang, Hong; Zhu, Qiuan; Wang, Weifeng

    2013-01-01

    Ultraviolet-B (UV-B) exposure in the course of litter decomposition may have a direct effect on decomposition rates via changing states of photodegradation or decomposer constitution in litter while UV-B exposure during growth periods may alter chemical compositions and physical properties of plants. Consequently, these changes will indirectly affect subsequent litter decomposition processes in soil. Although studies are available on both the positive and negative effects (including no observable effects) of UV-B exposure on litter decomposition, a comprehensive analysis leading to an adequate understanding remains unresolved. Using data from 93 studies across six biomes, this introductory meta-analysis found that elevated UV-B directly increased litter decomposition rates by 7% and indirectly by 12% while attenuated UV-B directly decreased litter decomposition rates by 23% and indirectly increased litter decomposition rates by 7%. However, neither positive nor negative effects were statistically significant. Woody plant litter decomposition seemed more sensitive to UV-B than herbaceous plant litter except under conditions of indirect effects of elevated UV-B. Furthermore, levels of UV-B intensity significantly affected litter decomposition response to UV-B (P<0.05). UV-B effects on litter decomposition were to a large degree compounded by climatic factors (e.g., MAP and MAT) (P<0.05) and litter chemistry (e.g., lignin content) (P<0.01). Results suggest these factors likely have a bearing on masking the important role of UV-B on litter decomposition. No significant differences in UV-B effects on litter decomposition were found between study types (field experiment vs. laboratory incubation), litter forms (leaf vs. needle), and decay duration. Indirect effects of elevated UV-B on litter decomposition significantly increased with decay duration (P<0.001). Additionally, relatively small changes in UV-B exposure intensity (30%) had significant direct effects on litter

  3. Allelopathic Effects of Litter Axonopus compressus against Two Weedy Species and Its Persistence in Soil

    PubMed Central

    Samedani, B.; Juraimi, A. S.; Rafii, M. Y.; Anuar, A. R.; Sheikh Awadz, S. A.; Anwar, M. P.

    2013-01-01

    This study investigated the allelopathic effect of Axonopus compressus litter on Asystasia gangetica and Pennisetum polystachion. In experiment 1 the bioassays with 0, 10, 30, and 50 g L−1 of aqueous A. compressus litter leachate were conducted. Experiment 2 was carried out by incorporating 0, 10, 20, 30, 40, and 50 g L−1 of A. compressus litter leachate into soil. In experiment 3, the fate of A. compressus litter leachate phenolics in the soil was investigated. A. compressus leachates did not affect the germination percentage of A. gangetica and P. polystachion, but delayed germination of A. gangetica seeds and decreased seed germination time of P. polystachion. A. compressus litter leachates affected weeds hypocotyl length. Hypocotyl length reductions of 18 and 31% were observed at the highest concentration (50 g L−1) compared to the control in A. gangetica and P. polystachion, respectively. When concentration of A. compressus litter leachate-amended soil increased A. gangetica and P. polystachion seedling shoot length, root length, seedling weight and chlorophyll concentration were not affected. The 5-week decomposition study of A. compressus showed that the phenolic compounds in A. compressus litter abruptly decreased about 52% after two weeks and remained steady until the end of the incubation. PMID:24260020

  4. Allelopathic effects of litter Axonopus compressus against two weedy species and its persistence in soil.

    PubMed

    Samedani, B; Juraimi, A S; Rafii, M Y; Anuar, A R; Sheikh Awadz, S A; Anwar, M P

    2013-01-01

    This study investigated the allelopathic effect of Axonopus compressus litter on Asystasia gangetica and Pennisetum polystachion. In experiment 1 the bioassays with 0, 10, 30, and 50 g L⁻¹ of aqueous A. compressus litter leachate were conducted. Experiment 2 was carried out by incorporating 0, 10, 20, 30, 40, and 50 g L⁻¹ of A. compressus litter leachate into soil. In experiment 3, the fate of A. compressus litter leachate phenolics in the soil was investigated. A. compressus leachates did not affect the germination percentage of A. gangetica and P. polystachion, but delayed germination of A. gangetica seeds and decreased seed germination time of P. polystachion. A. compressus litter leachates affected weeds hypocotyl length. Hypocotyl length reductions of 18 and 31% were observed at the highest concentration (50 g L⁻¹) compared to the control in A. gangetica and P. polystachion, respectively. When concentration of A. compressus litter leachate-amended soil increased A. gangetica and P. polystachion seedling shoot length, root length, seedling weight and chlorophyll concentration were not affected. The 5-week decomposition study of A. compressus showed that the phenolic compounds in A. compressus litter abruptly decreased about 52% after two weeks and remained steady until the end of the incubation.

  5. McDonald's Litter Hunt: A Community Litter Control System for Youth.

    ERIC Educational Resources Information Center

    McNees, M. Patrick; And Others

    1979-01-01

    Describes a community litter control program. Special adhesive stickers were randomly placed on existing litter throughout a community and youth were rewarded with special prizes for participating in the program. Litter was reduced 32 percent across the city. (Author/MA)

  6. Development of a phosphorus index for pastures fertilized with poultry litter--factors affecting phosphorus runoff.

    PubMed

    DeLaune, Paul B; Moore, Philip A; Carman, Dennis K; Sharpley, Andrew N; Haggard, Brian E; Daniel, Tommy C

    2004-01-01

    Currently, several state and federal agencies are proposing upper limits on soil test phosphorus (P), above which animal manures cannot be applied, based on the assumption that high P concentrations in runoff are due to high soil test P. Recent studies show that other factors are more indicative of P concentrations in runoff from areas where manure is being applied. The original P index was developed as an alternative P management tool incorporating factors affecting both the source and transport of P. The objective of this research was to evaluate the effects of multiple variables on P concentrations in runoff water and to construct a P source component of a P index for pastures that incorporates these effects. The evaluated variables were: (i) soil test P, (ii) soluble P in poultry litter, (iii) P in poultry diets, (iv) fertilizer type, and (v) poultry litter application rate. Field studies with simulated rainfall showed that P runoff was affected by the amount of soluble P applied in the fertilizer source. Before manure applications, soil test P was directly related to soluble P concentrations in runoff water. However, soil test P had little effect on P runoff after animal manure was applied. Unlike most other P indices, weighting factors of the P source components in the P index for pastures are based on results from runoff studies conducted under various management scenarios. As a result, weighting factors for the P source potential variables are well justified. A modification of the P index using scientific data should strengthen the ability of the P index concept to evaluate locations and management alternatives for P losses.

  7. Nonculturability Might Underestimate the Occurrence of Campylobacter in Broiler Litter.

    PubMed

    Kassem, Issmat I; Helmy, Yosra A; Kathayat, Dipak; Candelero-Rueda, Rosario A; Kumar, Anand; Deblais, Loic; Huang, Huang-Chi; Sahin, Orhan; Zhang, Qijing; Rajashekara, Gireesh

    2017-08-01

    We investigated the contribution of litter to the occurrence of Campylobacter on three broiler farms, which were known to have low (LO) and high (HI-A and HI-B) Campylobacter prevalence. For this purpose, we collected litter samples (n = 288) during and after two rearing cycles from each farm. We evaluated the occurrence of Campylobacter (using selective enrichment and quantitative real-time polymerase chain reaction [q-PCR] analysis) in the litter samples as well as the litter's pH and moisture content. Ceca from each flock (n = 144) were harvested at slaughter age and used to quantify Campylobacter colony-forming units (CFUs). Campylobacter was only retrieved from 7 litter samples that were collected from HI-A and HI-B during the growing period, but no Campylobacter was isolated from LO farms. The q-PCR analysis detected Campylobacter in pooled litter samples from all three farms. However, in litter collected during the same rotation, Campylobacter levels were significantly higher (p < 0.05) in HI-A and HI-B litter samples in comparison to those in LO. Cecal samples from HI-A and HI-B yielded relatively high numbers of Campylobacter CFUs, which were undetectable in LO samples. Litter's pH and moisture did not affect the overall occurrence of Campylobacter in litter and ceca on any of the farms. Our data suggest that Campylobacter was generally more abundant in litter that was collected from farms with highly colonized flocks. Therefore, better approaches for assessing the occurrence of Campylobacter in litter might be warranted in order to reduce the dissemination of these pathogens on and off poultry farms.

  8. Contrasting effects of plant species traits and moisture on the decomposition of multiple litter fractions.

    PubMed

    Riggs, Charlotte E; Hobbie, Sarah E; Cavender-Bares, Jeannine; Savage, Jessica A; Wei, Xiaojing

    2015-10-01

    Environmental variation in moisture directly influences plant litter decomposition through effects on microbial activity, and indirectly via plant species traits. Whether the effects of moisture and plant species traits are mutually reinforcing or counteracting during decomposition are unknown. To disentangle the effects of moisture from the effects of species traits that vary with moisture, we decomposed leaf litter from 12 plant species in the willow family (Salicaceae) with different native habitat moisture preferences in paired mesic and wetland plots. We fit litter mass loss data to an exponential decomposition model and estimated the decay rate of the rapidly cycling litter fraction and size of the remaining fraction that decays at a rate approaching zero. Litter traits that covaried with moisture in the species' native habitat significantly influenced the decomposition rate of the rapidly cycling litter fraction, but moisture in the decomposition environment did not. In contrast, for the slowly cycling litter fraction, litter traits that did not covary with moisture in the species' native habitat and moisture in the decomposition environment were significant. Overall, the effects of moisture and plant species traits on litter decomposition were somewhat reinforcing along a hydrologic gradient that spanned mesic upland to wetland (but not permanently surface-saturated) plots. In this system, plant trait and moisture effects may lead to greater in situ decomposition rates of wetland species compared to upland species; however, plant traits that do not covary with moisture will also influence decomposition of the slowest cycling litter fraction.

  9. Litter accumulation and nutrient content of roadside plant communities in Sichuan Basin, China

    USDA-ARS?s Scientific Manuscript database

    It is widely recognized that plant community composition strongly influences plant litter, but this relationship is difficult to interpret over heterogeneous conditions typical of modified environments such as roadways. We characterized litter accumulation and nutrient content (i.e., organic C, tota...

  10. Ingestion of marine litter by loggerhead sea turtles, Caretta caretta, in Portuguese continental waters.

    PubMed

    Nicolau, Lídia; Marçalo, Ana; Ferreira, Marisa; Sá, Sara; Vingada, José; Eira, Catarina

    2016-02-15

    The accumulation of litter in marine and coastal environments is a major threat to marine life. Data on marine litter in the gastrointestinal tract of stranded loggerhead turtles, Caretta caretta, found along the Portuguese continental coast was presented. Out of the 95 analysed loggerheads, litter was present in 56 individuals (59.0%) and most had less than 10 litter items (76.8%) and less than 5 g (dm) (96.8%). Plastic was the main litter category (frequency of occurrence=56.8%), while sheet (45.3%) was the most relevant plastic sub-category. There was no influence of loggerhead stranding season, cause of stranding or size on the amount of litter ingested (mean number and dry mass of litter items per turtle). The high ingested litter occurrence frequency in this study supports the use of the loggerhead turtle as a suitable tool to monitor marine litter trends, as required by the European Marine Strategy Framework Directive. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Riparian litter inputs to streams in the central Oregon Coast Range

    USGS Publications Warehouse

    Hart, Stephanie K.; Hibbs, David E.; Perakis, Steven S.

    2013-01-01

    Riparian-zone vegetation can influence terrestrial and aquatic food webs through variation in the amount, timing, and nutritional content of leaf and other litter inputs. We investigated how riparian-forest community composition, understory density, and lateral slope shaped vertical and lateral litter inputs to 16 streams in the Oregon Coast Range. Riparian forests dominated by deciduous red alder delivered greater annual vertical litter inputs to streams (504 g m−2 y−1) than did riparian forests dominated by coniferous Douglas-fir (394 g m−2 y−1). Deciduous forests also contributed greater lateral litter inputs per meter of stream bank on one side (109 g m−1 y−1) than did coniferous forests (63 g m−1 y−1). Total litter inputs from deciduous forests exceeded those from coniferous forests most strongly in November, coincident with an autumn peak in litter inputs. Lateral litter inputs contributed most to total inputs during winter in both forest types. Annual lateral litter movement increased with slope at deciduous sites, but only in spring/summer months at coniferous sites. Neither experimental removal of understory vegetation nor installation of mesh fences to block downslope litter movement affected lateral litter inputs to streams, suggesting that ground litter moves <5 m downslope annually. N concentrations of several litter fractions were higher at deciduous sites and, when combined with greater litter amounts, yielded twice as much total litter N flux to streams in deciduous than coniferous sites. The presence of red alder in riparian forests along many small streams of the deeply incised and highly dendritic basins of the Oregon Coast Range enhances total fluxes and seasonality of litter delivery to both terrestrial and aquatic food webs in this region and complements the shade and large woody debris provided by large coniferous trees.

  12. Monitoring multi-year macro ocean litter dynamics and backward-tracking simulation of litter origins on a remote island in the South China Sea

    NASA Astrophysics Data System (ADS)

    Ko, Chia-Ying; Hsin, Yi-Chia; Yu, Teng-Lang; Liu, Kuo-Lieh; Shiah, Fuh-Kwo; Jeng, Ming-Shiou

    2018-04-01

    (> 2 years) before drifting onto Dongsha Island. The estimated drifting time of macro ocean litter also showed monthly and directional variability. This study demonstrated that a tremendous quantity of macro ocean litter, which may cause great damage to the marine ecosystem, drifts in the ocean surface layer and is finally pushed onto beaches. Therefore, we proposed an action plan for effective ocean litter management development at regional and global spatial scales, which is vital for improving and restoring the health and sustainability of the oceanic environment.

  13. Ammonia volatilization from surface-applied poultry litter under conservation tillage management practices.

    PubMed

    Sharpe, R R; Schomberg, H H; Harper, L A; Endale, D M; Jenkins, M B; Franzluebbers, A J

    2004-01-01

    Land application of poultry litter can provide essential plant nutrients for crop production, but ammonia (NH(3)) volatilization from the litter can be detrimental to the environment. A multiseason study was conducted to quantify NH(3) volatilization rates from surface-applied poultry litter under no-till and paraplowed conservation tillage managements. Litter was applied to supply 90 to 140 kg N ha(-1). Evaluation of NH(3) volatilization was determined using gas concentrations and the flux-gradient gas transport technique using the momentum balance transport coefficient. Ammonia fluxes ranged from 3.3 to 24% of the total N applied during the winter and summer, respectively. Ammonia volatilization was rapid immediately after litter application and stopped within 7 to 8 d. Precipitation of 17 mm essentially halted volatilization, probably by transporting litter N into the soil matrix. Application of poultry to conservation-tilled cropland immediately before rainfall events would reduce N losses to the atmosphere but could also increase NO(3) leaching and runoff to streams and rivers.

  14. Are litter decomposition and fire linked through plant species traits?

    PubMed

    Cornelissen, Johannes H C; Grootemaat, Saskia; Verheijen, Lieneke M; Cornwell, William K; van Bodegom, Peter M; van der Wal, René; Aerts, Rien

    2017-11-01

    Contents 653 I. 654 II. 657 III. 659 IV. 661 V. 662 VI. 663 VII. 665 665 References 665 SUMMARY: Biological decomposition and wildfire are connected carbon release pathways for dead plant material: slower litter decomposition leads to fuel accumulation. Are decomposition and surface fires also connected through plant community composition, via the species' traits? Our central concept involves two axes of trait variation related to decomposition and fire. The 'plant economics spectrum' (PES) links biochemistry traits to the litter decomposability of different fine organs. The 'size and shape spectrum' (SSS) includes litter particle size and shape and their consequent effect on fuel bed structure, ventilation and flammability. Our literature synthesis revealed that PES-driven decomposability is largely decoupled from predominantly SSS-driven surface litter flammability across species; this finding needs empirical testing in various environmental settings. Under certain conditions, carbon release will be dominated by decomposition, while under other conditions litter fuel will accumulate and fire may dominate carbon release. Ecosystem-level feedbacks between decomposition and fire, for example via litter amounts, litter decomposition stage, community-level biotic interactions and altered environment, will influence the trait-driven effects on decomposition and fire. Yet, our conceptual framework, explicitly comparing the effects of two plant trait spectra on litter decomposition vs fire, provides a promising new research direction for better understanding and predicting Earth surface carbon dynamics. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  15. Effect of moisture content on the heating profile in composted broiler litter

    USDA-ARS?s Scientific Manuscript database

    Moisture content can affect the magnitude of heat generation during composting. Temperature was recorded every 2 min for 7 d at 10-cm increments throughout the vertical profile of broiler litter treated with five quantities of water addition. Water additions were applied to achieve litter moisture...

  16. The use of refused tea as litter material for broiler chickens.

    PubMed

    Atapattu, N S B M; Wickramasinghe, K P

    2007-05-01

    A completely randomized design experiment was conducted to determine the suitability of refused tea (RT) as a litter material for broiler chickens. Physiochemical properties of RT were compared with paddy husk (PH). Subsequently, broilers were raised on RT- or PH-based litter to compare the performances and litter qualities. Twenty-day-old broiler chicks (n = 150) were randomly allocated into 6 deep litter pens so that each treatment had 3 replicates. Chicks received 0.8 ft(2) of floor spacing until d 28 and 1.3 ft(2) thereafter. Each cage had a feeder and a drinker. Litter materials and litter samples taken on 28, 35, and 39 d were analyzed for bulk density, moisture, ash, and N. Chick mortality was low (1.3%) and similar on 2 types of litters. Live weights on d 28, 35, 39, and weight gains, feed intakes, dressing percentages, and feed conversion ratios were not affected by the type of litter material. The bulk density, moisture level, and pH of the RT were comparable with PH. Even though the water-holding capacity of PH (213%) was significantly higher (P < 0.01) than RT (70%), the latter material had significantly higher (P < 0.01) water-releasing capacity compared with the former (17.9 vs. 13.6%). Throughout the experiment the RT litter had around 10% units higher moisture level than PH litter. By d 39, the moisture content of the RT litter was (48%) significantly higher (P = 0.05) than PH litter (37%). The N contents of RT litter were higher (P < 0.05) than those of PH on d 28, 35, and 39, being 8.1, 7.8, and 7% and 3.4, 3.6, and 3%, respectively. It was concluded that RT could be successfully used as an alternative litter material for broilers. A higher N content in RT-based spent broiler litter would make it be a better organic fertilizer and ruminant feed compared with PH-based litter.

  17. Negative and positive interactions among plants: effects of competitors and litter on seedling emergence and growth of forest and grassland species.

    PubMed

    Loydi, A; Donath, T W; Otte, A; Eckstein, R L

    2015-05-01

    Living plant neighbours, but also their dead aboveground remains (i.e. litter), may individually exert negative or positive effects on plant recruitment. Although living plants and litter co-occur in most ecosystems, few studies have addressed their combined effects, and conclusions are ambivalent. Therefore, we examined the response in terms of seedling emergence and growth of herbaceous grassland and forest species to different litter types and amounts and the presence of competitors. We conducted a pot experiment testing the effects of litter type (grass, oak), litter amount (low, medium, high) and interspecific competition (presence or absence of four Festuca arundinacea individuals) on seedling emergence and biomass of four congeneric pairs of hemicryptophytes from two habitat types (woodland, grassland). Interactions between litter and competition were weak. Litter presence increased competitor biomass. It also had positive effects on seedling emergence at low litter amounts and negative effects at high litter amounts, while competition had no effect on seedling emergence. Seedling biomass was negatively affected by the presence of competitors, and this effect was stronger in combination with high amounts of litter. Litter affected seedling emergence while competition determined the biomass of the emerged individuals, both affecting early stages of seedling recruitment. High litter accumulation also reduced seedling biomass, but this effect seemed to be additive to competitor effects. This suggests that live and dead plant mass can affect species recruitment in natural systems, but the mechanisms by which they operate and their timing differ. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  18. Effects of neonatal litter size and age on ovarian gene expression and follicular development in gilts

    USDA-ARS?s Scientific Manuscript database

    Gilts raised in small litters have greater ovulation rate, stay in the herd longer and produce more pigs. The objective was to understand how neonatal litter size affects gilt development. The hypothesis is that gilts reared in smaller litters have greater ovarian follicular development. Within 24 h...

  19. Litter survey in Virginia.

    DOT National Transportation Integrated Search

    1976-01-01

    This report summarizes the findings of the litter survey for highways, urban areas, and recreational areas as specified in the "Virginia Litter Control Act". Litter samples from 61 highway sites, 11 urban sites, and 10 recreational sites geographical...

  20. Within-litter differences in personality and physiology relate to size differences among siblings in cavies.

    PubMed

    Guenther, A; Trillmich, F

    2015-06-01

    Many aspects of an animal's early life potentially contribute to long-term individual differences in physiology and behaviour. From several studies on birds and mammals it is known that the early family environment is one of the most prominent factors influencing early development. Most of these studies were conducted on highly altricial species. Here we asked whether in the highly precocial cavy (Cavia aperea) the size rank within a litter, i.e. whether an individual is born as the heaviest, the lightest or an intermediate sibling, affects personality traits directly after birth and after independence. Furthermore, we investigated whether individual states (early growth, baseline cortisol and resting metabolic rate) differ between siblings of different size ranks and assessed their relation to personality traits. Siblings of the same litter differed in personality traits as early as three days after birth. Pups born heaviest in the litter were more explorative and in general more risk-prone than their smaller siblings. Physiological state variables were tightly correlated with personality traits and also influenced by the size rank within litter, suggesting that the size relative to littermates constitutes an important factor in shaping an individual's developmental trajectory. Our data add valuable information on how personalities are shaped during early phases of life and indicate the stability of developmentally influenced behavioural and physiological traits. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity.

    PubMed

    Fossi, Maria Cristina; Pedà, Cristina; Compa, Montserrat; Tsangaris, Catherine; Alomar, Carme; Claro, Francoise; Ioakeimidis, Christos; Galgani, Francois; Hema, Tatjana; Deudero, Salud; Romeo, Teresa; Battaglia, Pietro; Andaloro, Franco; Caliani, Ilaria; Casini, Silvia; Panti, Cristina; Baini, Matteo

    2018-06-01

    The Mediterranean Sea has been described as one of the most affected areas by marine litter in the world. Although effects on organisms from marine plastic litter ingestion have been investigated in several oceanic areas, there is still a lack of information from the Mediterranean Sea. The main objectives of this paper are to review current knowledge on the impact of marine litter on Mediterranean biodiversity, to define selection criteria for choosing marine organisms suitable for use as bioindicator species, and to propose a methodological approach to assessing the harm related to marine litter ingestion in several Mediterranean habitats and sub-regions. A new integrated monitoring tool that would provide the information necessary to design and implement future mitigation actions in the Mediterranean basin is proposed. According to bibliographic research and statistical analysis on current knowledge of marine litter ingestion, the area of the Mediterranean most studied, in terms of number of species and papers in the Mediterranean Sea is the western sub-area as well as demersal (32.9%) and pelagic (27.7%) amongst habitats. Applying ecological and biological criteria to the most threatened species obtained by statistical analysis, bioindicator species for different habitats and monitoring scale were selected. A threefold approach, simultaneously measuring the presence and effects of plastic, can provide the actual harm and sub-lethal effects to organisms caused by marine litter ingestion. The research revealed gaps in knowledge, and this paper suggests measures to close the gap. This and the selection of appropriate bioindicator species would represent a step forward for marine litter risk assessment, and the implementation of future actions and mitigation measures for specific Mediterranean areas, habitats and species affected by marine litter ingestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Effects of litter addition on ectomycorrhizal associates of a lodgepole pine (Pinus contorta) stand in Yellowstone National Park

    NASA Technical Reports Server (NTRS)

    Cullings, Kenneth W.; New, Michael H.; Makhija, Shilpa; Parker, V. Thomas

    2003-01-01

    Increasing soil nutrients through litter manipulation, pollution, or fertilization can adversely affect ectomycorrhizal (EM) communities by inhibiting fungal growth. In this study, we used molecular genetic methods to determine the effects of litter addition on the EM community of a Pinus contorta stand in Yellowstone National Park that regenerated after a stand-replacing fire. Two controls were used; in unmodified control plots nothing was added to the soil, and in perlite plots perlite, a chemically neutral substance, was added to maintain soil moisture and temperature at levels similar to those under litter. We found that (i) species richness did not change significantly following perlite addition (2.6 +/- 0.3 species/core in control plots, compared with 2.3 +/- 0.3 species/core in perlite plots) but decreased significantly (P < 0.05) following litter addition (1.8 +/- 0.3 species/core); (ii) EM infection was not affected by the addition of perlite but increased significantly (P < 0.001) in response to litter addition, and the increase occurred only in the upper soil layer, directly adjacent to the added litter; and (iii) Suillus granulatus, Wilcoxina mikolae, and agaricoid DD were the dominant organisms in controls, but the levels of W. mikolae and agaricoid DD decreased significantly in response to both perlite and litter addition. The relative levels of S. granulatus and a fourth fungus, Cortinariaceae species 2, increased significantly (P < 0.01 and P < 0.05, respectively) following litter addition. Thus, litter addition resulted in some negative effects that may be attributable to moisture-temperature relationships rather than to the increased nutrients associated with litter. Some species respond positively to litter addition, indicating that there are differences in their physiologies. Hence, changes in the EM community induced by litter accumulation also may affect ecosystem function.

  3. Evaluation of litter type and dietary coarse ground corn inclusion on broiler live performance, gastrointestinal tract development, and litter characteristics.

    PubMed

    Xu, Y; Stark, C R; Ferket, P R; Williams, C M; Nusairat, B; Brake, J

    2015-03-01

    Two 49 d floor pen studies were conducted to evaluate the effects of litter type and dietary coarse ground corn (CC) inclusion on broiler live performance, gastrointestinal tract (GIT) development, and litter characteristics. Experiment 1 was a 2×2 factorial arrangement of 2 genders (male or female) and 2 CC levels (0 or 50%). From 15 to 35 d, the addition of CC decreased feed intake (P<0.01) and BW gain (P<0.05) of males but not females. The inclusion of CC decreased feed intake (P<0.01) and BW gain (P<0.01) from 0 to 49 d but improved adjusted feed conversion ratio (AdjFCR) from 35 to 49 d (P<0.05). Male broilers exhibited better live performance than females during the study as evidenced by greater feed intake (P<0.01) and BW gain (P<0.01), and improved FCR (P<0.01), but with increased mortality (P<0.05). The inclusion of CC increased relative gizzard weight (P<0.01) and decreased relative proventriculus weight (P<0.01) at 49 d. Experiment 2 was a 2×2 factorial arrangement of 2 CC levels (0 or 50%) and 2 litter types (ground old litter or new wood shavings litter). The inclusion of CC decreased feed intake throughout the experiment without affecting final BW when only males were used and improved FCR after 25 d (P<0.01). New litter improved FCR from 1 to 14 d (P<0.01). At 49 d, the birds fed the CC diet had reduced excreta nitrogen (P<0.05) and litter moisture (P<0.05). In conclusion, 50% CC inclusion initially produced negative effects on live performance that became positive as BW increased. The effects of CC became evident at an earlier age for males. New litter had only a marginal benefit on broiler live performance. © 2015 Poultry Science Association Inc.

  4. Impact of litter quantity on the soil bacteria community during the decomposition of Quercus wutaishanica litter.

    PubMed

    Zeng, Quanchao; Liu, Yang; An, Shaoshan

    2017-01-01

    The forest ecosystem is the main component of terrestrial ecosystems. The global climate and the functions and processes of soil microbes in the ecosystem are all influenced by litter decomposition. The effects of litter decomposition on the abundance of soil microorganisms remain unknown. Here, we analyzed soil bacterial communities during the litter decomposition process in an incubation experiment under treatment with different litter quantities based on annual litterfall data (normal quantity, 200 g/(m 2 /yr); double quantity, 400 g/(m 2 /yr) and control, no litter). The results showed that litter quantity had significant effects on soil carbon fractions, nitrogen fractions, and bacterial community compositions, but significant differences were not found in the soil bacterial diversity. The normal litter quantity enhanced the relative abundance of Actinobacteria and Firmicutes and reduced the relative abundance of Bacteroidetes, Plantctomycets and Nitrospiare. The Beta-, Gamma-, and Deltaproteobacteria were significantly less abundant in the normal quantity litter addition treatment, and were subsequently more abundant in the double quantity litter addition treatment. The bacterial communities transitioned from Proteobacteria-dominant (Beta-, Gamma-, and Delta) to Actinobacteria-dominant during the decomposition of the normal quantity of litter. A cluster analysis showed that the double litter treatment and the control had similar bacterial community compositions. These results suggested that the double quantity litter limited the shift of the soil bacterial community. Our results indicate that litter decomposition alters bacterial dynamics under the accumulation of litter during the vegetation restoration process, which provides important significant guidelines for the management of forest ecosystems.

  5. Using column experiments to examine transport of As and other trace elements released from poultry litter: Implications for trace element mobility in agricultural watersheds.

    PubMed

    Oyewumi, Oluyinka; Schreiber, Madeline E

    2017-08-01

    Trace elements are added to poultry feed to control infection and improve weight gain. However, the fate of these trace elements in poultry litter is poorly understood. Because poultry litter is applied as fertilizer in many agricultural regions, evaluation of the environmental processes that influence the mobility of litter-derived trace elements is critical for predicting if trace elements are retained in soil or released to water. This study examined the effect of dissolved organic carbon (DOC) in poultry litter leachate on the fate and transport of litter-derived elements (As, Cu, P and Zn) using laboratory column experiments with soil collected from the Delmarva Peninsula (Mid-Atlantic, USA), a region of intense poultry production. Results of the experiments showed that DOC enhanced the mobility of all of the studied elements. However, despite the increased mobility, 60-70% of Zn, As and P mass was retained within the soil. In contrast, almost all of the Cu was mobilized in the litter leachate experiments, with very little retention in soil. Overall, our results demonstrate that the mobility of As, Cu, Zn and P in soils which receive poultry litter application is strongly influenced by both litter leachate composition, specifically organic acids, and adsorption to soil. Results have implications for understanding fate and transport of trace elements released from litter application to soil water and groundwater, which can affect both human health and the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Climate and litter quality differently modulate the effects of soil fauna on litter decomposition across biomes

    PubMed Central

    García-Palacios, Pablo; Maestre, Fernando T.; Kattge, Jens; Wall, Diana H.

    2015-01-01

    Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesized litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~27%). However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. PMID:23763716

  7. Leaf Litter Mixtures Alter Microbial Community Development: Mechanisms for Non-Additive Effects in Litter Decomposition

    PubMed Central

    Chapman, Samantha K.; Newman, Gregory S.; Hart, Stephen C.; Schweitzer, Jennifer A.; Koch, George W.

    2013-01-01

    To what extent microbial community composition can explain variability in ecosystem processes remains an open question in ecology. Microbial decomposer communities can change during litter decomposition due to biotic interactions and shifting substrate availability. Though relative abundance of decomposers may change due to mixing leaf litter, linking these shifts to the non-additive patterns often recorded in mixed species litter decomposition rates has been elusive, and links community composition to ecosystem function. We extracted phospholipid fatty acids (PLFAs) from single species and mixed species leaf litterbags after 10 and 27 months of decomposition in a mixed conifer forest. Total PLFA concentrations were 70% higher on litter mixtures than single litter types after 10 months, but were only 20% higher after 27 months. Similarly, fungal-to-bacterial ratios differed between mixed and single litter types after 10 months of decomposition, but equalized over time. Microbial community composition, as indicated by principal components analyses, differed due to both litter mixing and stage of litter decomposition. PLFA biomarkers a15∶0 and cy17∶0, which indicate gram-positive and gram-negative bacteria respectively, in particular drove these shifts. Total PLFA correlated significantly with single litter mass loss early in decomposition but not at later stages. We conclude that litter mixing alters microbial community development, which can contribute to synergisms in litter decomposition. These findings advance our understanding of how changing forest biodiversity can alter microbial communities and the ecosystem processes they mediate. PMID:23658639

  8. Broiler diet modification and litter storage: impacts on phosphorus in litters, soils, and runoff.

    PubMed

    McGrath, Joshua M; Sims, J Thomas; Maguire, Rory O; Saylor, William W; Angel, C Roselina; Turner, Benjamin L

    2005-01-01

    Modifying broiler diets to mitigate water quality concerns linked to excess phosphorus (P) in regions of intensive broiler production has recently increased. Our goals were to evaluate the effects of dietary modification, using phytase and reduced non-phytate phosphorus (NPP) supplementation, on P speciation in broiler litters, changes in litter P forms during long-term storage, and subsequent impacts of diets on P in runoff from litter-amended soils. Four diets containing two levels of NPP with and without phytase were fed to broilers in a three-flock floor pen study. After removal of the third flock, litters were stored for 440 d at their initial moisture content (MC; 24%) and at a MC of 40%. Litter P fractions and orthophosphate and phytate P concentrations were determined before and after storage. After storage, litters were incorporated with a sandy and silt loam and simulated rainfall was applied. Phytase and reduced dietary NPP significantly reduced litter total P. Reducing dietary NPP decreased water-extractable inorganic phosphorus (IP) and the addition of dietary phytase reduced NaOH- and HCl-extractable organic P in litter, which correlated well with orthophosphate and phytic acid measured by 31P nuclear magnetic resonance (NMR), respectively. Although dry storage caused little change in P speciation, wet storage increased concentrations of water-soluble IP, which increased reactive P in runoff from litter-amended soils. Therefore, diet modification with phytase and reduced NPP could be effective in reducing P additions on a watershed scale. Moreover, efforts to minimize litter MC during storage may reduce the potential for dissolved P losses in runoff.

  9. Climate and litter quality differently modulate the effects of soil fauna on litter decomposition across biomes.

    PubMed

    García-Palacios, Pablo; Maestre, Fernando T; Kattge, Jens; Wall, Diana H

    2013-08-01

    Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesised litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~ 37%). [corrected]. However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. © 2013 John Wiley & Sons Ltd/CNRS.

  10. High dietary biotin levels affect the footpad and hock health of broiler chickens reared at different stocking densities and litter conditions.

    PubMed

    Sun, Z W; Fan, Q H; Wang, X X; Guo, Y M; Wang, H J; Dong, X

    2017-06-01

    Responses to stocking density (SD), dietary biotin concentration and litter condition were evaluated on 2016 Ross 308 male broilers in the fattening period (day 22-day 42). The birds were placed in 48 pens with either dry or wet litter to simulate the final stocking density of 30 kg (12 broilers/m 2 ; normal stocking density, NSD) and 40 kg (16 broilers/m 2 ; high stocking density, HSD) of body weight (BW)/m 2 floor space. A corn-soybean meal-based diet was supplemented with biotin to provide a normal (NB; 155 μg/kg) or high (HB, 1521 μg/kg) level of dietary biotin. There were six repetitions per treatment. The inappropriate moisture content of litter associated with HSD was avoided (p < 0.05) by good management (SD difference: dry litter, 6.65% vs. wet litter, 13.23%; 42 days), which made it advantageous (p < 0.01) for footpad (SD difference: dry litter, 0.118 vs. wet litter, 0.312; weekly average value) and hock health (SD difference: dry litter, 0.090 vs. wet litter, 0.303; weekly average value) of HSD birds, but not (p > 0.05) for growth and processing yield. In HSD, the biotin effect (gains, FCR) was significantly higher (p < 0.01) than in NSD. The similar response of HSD birds to supplemental biotin was observed (p < 0.05) for lesion scores of footpad and hock in particularly finishing chickens, and a significant interaction (p < 0.01) among stocking density, biotin supplementation and litter condition existed from 35 to 42 days of age. Taken together, increasing dietary biotin improves the performance and well-being of broiler chickens stocked at high densities in litter-independent and litter-dependent manners respectively. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  11. Comparing intra- and inter-specific effects on litter decomposition in an old-field ecosystem

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crutsinger, Greg; Sanders, Dr. Nathan James; Classen, Aimee T

    2009-09-01

    Plant species can differ in the quantity and quality of leaf litter they produce, and many studies have examined whether plant species diversity affects leaf-litter decomposition and nutrient release. A growing number of studies have indicated that intra-specific variation within plant species can also affect key ecosystem processes. However, the relative importance of intra- versus inter-specific variation for the functioning of ecosystems remains poorly known. Here, we investigate the effects of intra-specific variation in a dominant old-field plant species, tall goldenrod (Solidago altissima), and inter-specific variation among goldenrod species on litter quality, decomposition, and nitrogen (N) release. We found thatmore » the nutrient concentration of leaf litter varied among genotypes, which translated into 50% difference in decomposition rates. Variation among other goldenrod species in decomposition rate was more than twice that of genetic variation within S. altissima. Furthermore, by manipulating litterbags to contain 1, 3, 6, or 9 genotypes, we found that S. altissima genotype identity had much stronger effects than did genotypic diversity on leaf-litter quality, decomposition, and N release. Taken together, these results suggest that the order of ecological importance for controlling leaf-litter decomposition and N release dynamics is plant species identitygenotype identity>genotypic diversity.« less

  12. Warming and Nitrogen Addition Increase Litter Decomposition in a Temperate Meadow Ecosystem

    PubMed Central

    Gong, Shiwei; Guo, Rui; Zhang, Tao; Guo, Jixun

    2015-01-01

    Background Litter decomposition greatly influences soil structure, nutrient content and carbon sequestration, but how litter decomposition is affected by climate change is still not well understood. Methodology/Principal Findings A field experiment with increased temperature and nitrogen (N) addition was established in April 2007 to examine the effects of experimental warming, N addition and their interaction on litter decomposition in a temperate meadow steppe in northeastern China. Warming, N addition and warming plus N addition reduced the residual mass of L. chinensis litter by 3.78%, 7.51% and 4.53%, respectively, in 2008 and 2009, and by 4.73%, 24.08% and 16.1%, respectively, in 2010. Warming, N addition and warming plus N addition had no effect on the decomposition of P. communis litter in 2008 or 2009, but reduced the residual litter mass by 5.58%, 15.53% and 5.17%, respectively, in 2010. Warming and N addition reduced the cellulose percentage of L. chinensis and P. communis, specifically in 2010. The lignin percentage of L. chinensis and P. communis was reduced by warming but increased by N addition. The C, N and P contents of L. chinensis and P. communis litter increased with time. Warming and N addition reduced the C content and C:N ratios of L. chinensisand P. communis litter, but increased the N and P contents. Significant interactive effects of warming and N addition on litter decomposition were observed (P<0.01). Conclusion/Significance The litter decomposition rate was highly correlated with soil temperature, soil water content and litter quality. Warming and N addition significantly impacted the litter decomposition rate in the Songnen meadow ecosystem, and the effects of warming and N addition on litter decomposition were also influenced by the quality of litter. These results highlight how climate change could alter grassland ecosystem carbon, nitrogen and phosphorus contents in soil by influencing litter decomposition. PMID:25774776

  13. Shifts in leaf litter breakdown along a forest-pasture-urban gradient in Andean streams.

    PubMed

    Iñiguez-Armijos, Carlos; Rausche, Sirkka; Cueva, Augusta; Sánchez-Rodríguez, Aminael; Espinosa, Carlos; Breuer, Lutz

    2016-07-01

    Tropical montane ecosystems of the Andes are critically threatened by a rapid land-use change which can potentially affect stream variables, aquatic communities, and ecosystem processes such as leaf litter breakdown. However, these effects have not been sufficiently investigated in the Andean region and at high altitude locations in general. Here, we studied the influence of land use (forest-pasture-urban) on stream physico-chemical variables (e.g., water temperature, nutrient concentration, and pH), aquatic communities (macroinvertebrates and aquatic fungi) and leaf litter breakdown rates in Andean streams (southern Ecuador), and how variation in those stream physico-chemical variables affect macroinvertebrates and fungi related to leaf litter breakdown. We found that pH, water temperature, and nutrient concentration increased along the land-use gradient. Macroinvertebrate communities were significantly different between land uses. Shredder richness and abundance were lower in pasture than forest sites and totally absent in urban sites, and fungal richness and biomass were higher in forest sites than in pasture and urban sites. Leaf litter breakdown rates became slower as riparian land use changed from natural to anthropogenically disturbed conditions and were largely determined by pH, water temperature, phosphate concentration, fungal activity, and single species of leaf-shredding invertebrates. Our findings provide evidence that leaf litter breakdown in Andean streams is sensitive to riparian land-use change, with urban streams being the most affected. In addition, this study highlights the role of fungal biomass and shredder species (Phylloicus; Trichoptera and Anchytarsus; Coleoptera) on leaf litter breakdown in Andean streams and the contribution of aquatic fungi in supporting this ecosystem process when shredders are absent or present low abundance in streams affected by urbanization. Finally, we summarize important implications in terms of managing of

  14. Microbial decomposition is highly sensitive to leaf litter emersion in a permanent temperate stream.

    PubMed

    Mora-Gómez, Juanita; Duarte, Sofia; Cássio, Fernanda; Pascoal, Cláudia; Romaní, Anna M

    2018-04-15

    Drought frequency and intensity in some temperate regions are forecasted to increase under the ongoing global change, which might expose permanent streams to intermittence and have severe repercussions on stream communities and ecosystem processes. In this study, we investigated the effect of drought duration on microbial decomposition of Populus nigra leaf litter in a temperate permanent stream (Oliveira, NW Portugal). Specifically, we measured the response of the structural (assemblage composition, bacterial and fungal biomass) and functional (leaf litter decomposition, extracellular enzyme activities (EEA), and fungal sporulation) parameters of fungal and bacterial communities on leaf litter exposed to emersion during different time periods (7, 14 and 21d). Emersion time affected microbial assemblages and litter decomposition, but the response differed among variables. Leaf decomposition rates and the activity of β-glucosidase, cellobiohydrolase and phosphatase were gradually reduced with increasing emersion time, while β-xylosidase reduction was similar when emersion last for 7 or more days, and the phenol oxidase reduction was similar at 14 and 21days of leaf emersion. Microbial biomass and fungal sporulation were reduced after 21days of emersion. The structure of microbial assemblages was affected by the duration of the emersion period. The shifts in fungal assemblages were correlated with a decreased microbial capacity to degrade lignin and hemicellulose in leaf litter exposed to emersion. Additionally, some resilience was observed in leaf litter mass loss, bacterial biomass, some enzyme activities and structure of fungal assemblages. Our study shows that drought can strongly alter structural and functional aspects of microbial decomposers. Therefore, the exposure of leaf litter to increasing emersion periods in temperate streams is expected to affect decomposer communities and overall decomposition of plant material by decelerating carbon cycling in

  15. 40 CFR 1502.15 - Affected environment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Affected environment. 1502.15 Section 1502.15 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY ENVIRONMENTAL IMPACT STATEMENT § 1502.15 Affected environment. The environmental impact statement shall succinctly describe the...

  16. 40 CFR 1502.15 - Affected environment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Affected environment. 1502.15 Section 1502.15 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY ENVIRONMENTAL IMPACT STATEMENT § 1502.15 Affected environment. The environmental impact statement shall succinctly describe the...

  17. 40 CFR 1502.15 - Affected environment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Affected environment. 1502.15 Section 1502.15 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY ENVIRONMENTAL IMPACT STATEMENT § 1502.15 Affected environment. The environmental impact statement shall succinctly describe the...

  18. 40 CFR 1502.15 - Affected environment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Affected environment. 1502.15 Section 1502.15 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY ENVIRONMENTAL IMPACT STATEMENT § 1502.15 Affected environment. The environmental impact statement shall succinctly describe the...

  19. 40 CFR 1502.15 - Affected environment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Affected environment. 1502.15 Section 1502.15 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY ENVIRONMENTAL IMPACT STATEMENT § 1502.15 Affected environment. The environmental impact statement shall succinctly describe the...

  20. Marine litter on deep Arctic seafloor continues to increase and spreads to the North at the HAUSGARTEN observatory

    NASA Astrophysics Data System (ADS)

    Tekman, Mine B.; Krumpen, Thomas; Bergmann, Melanie

    2017-02-01

    The increased global production of plastics has been mirrored by greater accumulations of plastic litter in marine environments worldwide. Global plastic litter estimates based on field observations account only for 1% of the total volumes of plastic assumed to enter the marine ecosystem from land, raising again the question 'Where is all the plastic? '. Scant information exists on temporal trends on litter transport and litter accumulation on the deep seafloor. Here, we present the results of photographic time-series surveys indicating a strong increase in marine litter over the period of 2002-2014 at two stations of the HAUSGARTEN observatory in the Arctic (2500 m depth). Plastic accounted for the highest proportion (47%) of litter recorded at HAUSGARTEN for the whole study period. When the most southern station was considered separately, the proportion of plastic items was even higher (65%). Increasing quantities of small plastics raise concerns about fragmentation and future microplastic contamination. Analysis of litter types and sizes indicate temporal and spatial differences in the transport pathways to the deep sea for different categories of litter. Litter densities were positively correlated with the counts of ship entering harbour at Longyearbyen, the number of active fishing vessels and extent of summer sea ice. Sea ice may act as a transport vehicle for entrained litter, being released during periods of melting. The receding sea ice coverage associated with global change has opened hitherto largely inaccessible environments to humans and the impacts of tourism, industrial activities including shipping and fisheries, all of which are potential sources of marine litter.

  1. Effects of Nitrogen Addition on Litter Decomposition and CO2 Release: Considering Changes in Litter Quantity

    PubMed Central

    Li, Hui-Chao; Hu, Ya-Lin; Mao, Rong; Zhao, Qiong; Zeng, De-Hui

    2015-01-01

    This study aims to evaluate the impacts of changes in litter quantity under simulated N deposition on litter decomposition, CO2 release, and soil C loss potential in a larch plantation in Northeast China. We conducted a laboratory incubation experiment using soil and litter collected from control and N addition (100 kg ha−1 year−1 for 10 years) plots. Different quantities of litter (0, 1, 2 and 4 g) were placed on 150 g soils collected from the same plots and incubated in microcosms for 270 days. We found that increased litter input strongly stimulated litter decomposition rate and CO2 release in both control and N fertilization microcosms, though reduced soil microbial biomass C (MBC) and dissolved inorganic N (DIN) concentration. Carbon input (C loss from litter decomposition) and carbon output (the cumulative C loss due to respiration) elevated with increasing litter input in both control and N fertilization microcosms. However, soil C loss potentials (C output–C input) reduced by 62% in control microcosms and 111% in N fertilization microcosms when litter addition increased from 1 g to 4 g, respectively. Our results indicated that increased litter input had a potential to suppress soil organic C loss especially for N addition plots. PMID:26657180

  2. Marine Litter Distribution and Density in European Seas, from the Shelves to Deep Basins

    PubMed Central

    Pham, Christopher K.; Ramirez-Llodra, Eva; Alt, Claudia H. S.; Amaro, Teresa; Bergmann, Melanie; Canals, Miquel; Company, Joan B.; Davies, Jaime; Duineveld, Gerard; Galgani, François; Howell, Kerry L.; Huvenne, Veerle A. I.; Isidro, Eduardo; Jones, Daniel O. B.; Lastras, Galderic; Morato, Telmo; Gomes-Pereira, José Nuno; Purser, Autun; Stewart, Heather; Tojeira, Inês; Tubau, Xavier; Van Rooij, David; Tyler, Paul A.

    2014-01-01

    Anthropogenic litter is present in all marine habitats, from beaches to the most remote points in the oceans. On the seafloor, marine litter, particularly plastic, can accumulate in high densities with deleterious consequences for its inhabitants. Yet, because of the high cost involved with sampling the seafloor, no large-scale assessment of distribution patterns was available to date. Here, we present data on litter distribution and density collected during 588 video and trawl surveys across 32 sites in European waters. We found litter to be present in the deepest areas and at locations as remote from land as the Charlie-Gibbs Fracture Zone across the Mid-Atlantic Ridge. The highest litter density occurs in submarine canyons, whilst the lowest density can be found on continental shelves and on ocean ridges. Plastic was the most prevalent litter item found on the seafloor. Litter from fishing activities (derelict fishing lines and nets) was particularly common on seamounts, banks, mounds and ocean ridges. Our results highlight the extent of the problem and the need for action to prevent increasing accumulation of litter in marine environments. PMID:24788771

  3. Ammonia production in poultry houses can affect health of humans, birds, and the environment-techniques for its reduction during poultry production.

    PubMed

    Naseem, Sadia; King, Annie J

    2018-06-01

    Due to greater consumption of poultry products and an increase in exports, more poultry houses will be needed. Therefore, it is important to investigate ways that poultry facilities can coexist in close proximity to residential areas without odors and environmental challenges. Ammonia (NH 3 ) is the greatest concern for environmental pollution from poultry production. When birds consume protein, they produce uric acid, ultimately converted to NH 3 under favorable conditions. Factors that increase production include pH, temperature, moisture content, litter type, bird age, manure age, relative humidity, and ventilation rate (VR). NH 3 concentration and emissions in poultry houses depend on VR; seasons also have effects on NH 3 production. Modern ventilation systems can minimize NH 3 in enclosed production spaces quickly but increase its emissions to the environment. NH 3 adversely affects the ecosystem, environment, and health of birds and people. Less than 10 ppm is the ideal limit for exposure, but up to 25 ppm is also not harmful. NH 3 can be minimized by housing type, aerobic and anaerobic conditions, manure handling practices, litter amendment, and diet manipulation without affecting performance and production. Antibiotics can minimize NH 3 , but consumers have concerns about health effects. Administration of probiotics seems to be a useful replacement for antibiotics. More studies have been conducted on broilers, necessitating the need to evaluate the effect of probiotics on NH 3 production in conjunction with laying hen performance and egg quality. This comprehensive review focuses on research from 1950 to 2018.

  4. Litter quality impacts short- but not long-term soil carbon dynamics in soil aggregate fractions.

    PubMed

    Gentile, Roberta; Vanlauwe, Bernard; Six, Johan

    2011-04-01

    Complex molecules are presumed to be preferentially stabilized as soil organic carbon (SOC) based on the generally accepted concept that the chemical composition of litter is a major factor in its rate of decomposition. Hence, a direct link between litter quality and SOC quantity has been assumed, accepted, and ultimately incorporated in SOC models. Here, however, we present data from an incubation and field experiment that refutes the influence of litter quality on the quantity of stabilized SOC. Three different qualities of litter (Tithonia diversifolia, Calliandra calothyrsus, and Zea mays stover; 4 Mg C x ha(-1) yr(-1)) with and without the addition of mineral N fertilizer (0 or 120 kg N x ha(-1)season(-1) were added to a red clay Humic Nitisol in a 3-yr field trial and a 1.5-yr incubation experiment. The litters differed in their concentrations of N, lignin, and polyphenols with the ratio of (lignin + polyphenols): N ranging from 3.5 to 9.8 for the field trial and from 2.3 to 4.0 for the incubation experiment in the order of T. diversifolia < C. calothyrsus < or = Z. mays. Litter quality did not affect the amount of SOC stabilized after three annual additions in the field trial. Even within the most sensitive soil aggregate fractions, SOC contents and C:N ratios did not differ with litter quality, indicating that litter quality did not influence the mechanisms by which SOC was stabilized. While increasing litter quality displayed faster decomposition and incorporation of C into soil aggregates after 0.25 yr in the incubation study, all litters resulted in equivalent amounts of C stabilized in the soil after 1.5 yr, further corroborating the results of the field trial. The addition of N fertilizer did not affect SOC stabilization in either the field or the incubation trial. Thus, we conclude that, while litter quality controls shorter-term dynamics of C decomposition and accumulation in the soil, longer-term SOC patterns cannot be predicted based on initial

  5. Runoff quality from no-till cotton fertilized with broiler litter in subsurface bands.

    PubMed

    Adeli, A; Tewolde, H; Shankle, M W; Way, T R; Brooks, J P; McLaughlin, M R

    2013-01-01

    Surface broadcast of broiler litter to no-till row crops exposes the litter and its nutrients to risks of loss in runoff water and volatilization and may limit the potential benefit of litter to the crops. Subsurface banding of litter could alleviate these risks. A field study was conducted in 2008 and 2009 on an upland Falkner silt loam soil to determine the effect of broiler litter placement on runoff nutrient losses from no-till cotton ( L.). Treatments included surface broadcast broiler litter applied manually, subsurface-banded litter applied by tractor-drawn equipment, and no broiler litter, all in combination with or without winter wheat ( L.) cover crop residue. Broiler litter rate was 5.6 Mg ha. The experimental design was a randomized complete block with a split-plot arrangement of treatments replicated three times. In 2008, simulated rainfall was used to generate runoff 27 d after litter application. Subsurface-banded litter reduced runoff total C, N, P, NH, NO, Cu, Zn and water-soluble P (WP) concentrations by 72, 64, 51, 49, 70, 36, 65, and 77%, respectively, compared with surface broadcast. The reductions were greater in 2009 where runoff occurred 1 d after litter application. Bacterial runoff was decreased by one log with subsurface-banded litter compared to surface broadcast. Except for C, NH, N, and WP, the presence of winter cover crop residue did not affect the load or runoff nutrient concentrations in either year. The results indicate that subsurface banding litter to no-till cotton substantially reduces nutrient and bacterial losses in runoff compared with surface broadcasting. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. On the relationships between leaf-litter lignin and net primary productivity in tropical rain forests.

    PubMed

    Kitayama, Kanehiro; Suzuki, Shizuo; Hori, Masato; Takyu, Masaaki; Aiba, Shin-Ichiro; Majalap-Lee, Noreen; Kikuzawa, Kihachiro

    2004-07-01

    We investigated if tropical rainforest trees produced more-lignified leaves in less productive environments using forests on Mount Kinabalu, Borneo. Our investigation was based on two earlier suggestions that slower litter decomposition occurs under less productive forests and that trees under resource limitation invest a large amount of carbon as lignin as a defense substance to minimize the loss from herbivores. When nine forests at different altitudes (700-3100 m) and soil conditions (derived from sedimentary or ultrabasic rocks) but with the same gentle relief position were compared, the concentrations of leaf-litter lignin were positively correlated with litterfall rates and leaf-litter nitrogen concentrations. These patterns would be reinforced in intact leaves if the effects of resorption at the time of leaf shedding were taken into account, because greater magnitude of resorption of mobile elements but not of lignin would occur in less productive environments (i.e. dilution of lignin in intact leaves). These results did not support earlier suggestions to explain the variation of leaf-litter lignin. Instead, we suggest that lower lignin contents are adaptive to recycle minerals without retarding decomposition in less productive environments.

  7. Improving basic and translational science by accounting for litter-to-litter variation in animal models

    PubMed Central

    2013-01-01

    Background Animals from the same litter are often more alike compared with animals from different litters. This litter-to-litter variation, or “litter effects”, can influence the results in addition to the experimental factors of interest. Furthermore, sometimes an experimental treatment can only be applied to whole litters rather than to individual offspring. An example is the valproic acid (VPA) model of autism, where VPA is administered to pregnant females thereby inducing the disease phenotype in the offspring. With this type of experiment the sample size is the number of litters and not the total number of offspring. If such experiments are not appropriately designed and analysed, the results can be severely biased as well as extremely underpowered. Results A review of the VPA literature showed that only 9% (3/34) of studies correctly determined that the experimental unit (n) was the litter and therefore made valid statistical inferences. In addition, litter effects accounted for up to 61% (p <0.001) of the variation in behavioural outcomes, which was larger than the treatment effects. In addition, few studies reported using randomisation (12%) or blinding (18%), and none indicated that a sample size calculation or power analysis had been conducted. Conclusions Litter effects are common, large, and ignoring them can make replication of findings difficult and can contribute to the low rate of translating preclinical in vivo studies into successful therapies. Only a minority of studies reported using rigorous experimental methods, which is consistent with much of the preclinical in vivo literature. PMID:23522086

  8. The partitioning of litter carbon during litter decomposition under different rainfall patterns: a laboratory study

    NASA Astrophysics Data System (ADS)

    Yang, X.; Szlavecz, K. A.; Langley, J. A.; Pitz, S.; Chang, C. H.

    2017-12-01

    Quantifying litter C into different C fluxes during litter decomposition is necessary to understand carbon cycling under changing climatic conditions. Rainfall patterns are predicted to change in the future, and their effects on the fate of litter carbon are poorly understood. Soils from deciduous forests in Smithsonian Environmental Research Center (SERC) in Maryland, USA were collected to reconstruct soil columns in the lab. 13C labeled tulip poplar leaf litter was used to trace carbon during litter decomposition. Top 1% and the mean of 15-minute historical precipitation data from nearby weather stations were considered as extreme and control rainfall intensity, respectively. Both intensity and frequency of rainfall were manipulated, while the total amount was kept constant. A pulse of CO2 efflux was detected right after each rainfall event in the soil columns with leaf litter. After the first event, CO2 efflux of the control rainfall treatment soils increased to threefold of the CO2 efflux before rain event and that of the extreme treatment soils increased to fivefold. However, in soils without leaf litter, CO2 efflux was suppressed right after rainfall events. After each rainfall event, the leaf litter contribution to CO2 efflux first showed an increase, decreased sharply in the following two days, and then stayed relatively constant. In soil columns with leaf litter, the order of cumulative CO2 efflux was control > extreme > intermediate. The order of cumulative CO2 efflux in the bare soil treatment was extreme > intermediate > control. The order of volume of leachate from different treatments was extreme > intermediate > control. Our initial results suggest that more intense rainfall events result in larger pulses of CO2, which is rarely measured in the field. Additionally, soils with and without leaf litter respond differently to precipitation events. This is important to consider in temperate regions where leaf litter cover changes throughout the year

  9. Can't See the Wood for the Litter: Evaluation of Litter Behavior Modification in a Forest

    ERIC Educational Resources Information Center

    Lindemann-Matthies, Petra; Bonigk, Isabel; Benkowitz, Dorothee

    2012-01-01

    This study investigated elementary school children's (n = 171) litter behavior during guided forest tours following two different treatments. Four classes received a verbal appeal not to litter in the forest, while another four classes received both a verbal appeal and a demonstration of the desired litter behavior (picking up litter, putting it…

  10. Response of early Ruppia cirrhosa litter breakdown to nutrient addition in a coastal lagoon affected by agricultural runoff

    NASA Astrophysics Data System (ADS)

    Menéndez, Margarita

    2009-05-01

    The response of early Ruppia cirrhosa Petagna (Grande) litter decomposition to external nitrogen and phosphorus availability in La Tancada (Ebro River, NE Spain), a coastal lagoon that receives agricultural freshwater runoff from rice fields has been examined. Recently abscised dead R. cirrhosa stems were collected and 25 g of fresh weight was placed in litter bags with a mesh size of 100 μm and 1 mm. These bags were fertilised by adding nitrogen (N), a mixture of nitrogen plus phosphorus (N + P), or phosphorus (P), or were left untreated (CT). Macroinvertebrates were retrieved from the bags and the ash-free dry weight, and carbon, and N and P content of the remaining plant material were measured after 0, 3, 7, 14, 22 and 32 days. Litter decomposition rates, k (day -1), were estimated using a simple exponential model. Litter decay was clearly accelerated by the addition of P in the fine (100 μm) litter bags (0.042), but when N was added alone (0.0099) the decomposition rate was lower than in the CT treatments (0.022). No significant difference was observed between the N (0.0099-0.018) and N + P (0.0091-0.015) treatments in either the fine or the coarse (1 mm) litter bags. These results could be attributed to the relatively high availability of external (environmental) and internal (detritus contents) N. No significant effect of macro invertebrates was observed in the CT treatment or under N or P or N + P addition. The ratio between the decomposition rates in coarse and fine litter bags (k c/k f) was lower in disturbed Tancada lagoon (0.82) than in Cesine lagoon (2.11), a similar Mediterranean coastal water body with almost pristine conditions. These results indicate that, in addition to data on macroinvertebrate community structure, decomposition rates could also be used to assess water quality in coastal lagoons.

  11. The use of beached bird surveys for marine plastic litter monitoring in Ireland.

    PubMed

    Acampora, Heidi; Lyashevska, Olga; Van Franeker, Jan Andries; O'Connor, Ian

    2016-09-01

    Marine plastic litter has become a major threat to wildlife. Marine animals are highly susceptible to entanglement and ingestion of debris at sea. Governments all around the world are being urged to monitor litter sources and inputs, and to mitigate the impacts of marine litter, which is primarily composed of plastics. European policies, such as Oslo-Paris Convention (OSPAR) and Marine Strategy Framework Directive (MSFD) have adopted the monitoring of a seabird species, the Northern Fulmar (Fulmarus glacialis), as an environmental quality indicator through the analysis of stomach contents of beached Fulmar specimens. The aims of this research were to: firstly set a baseline investigation of multispecies of seabirds in Ireland affected by the ingestion of litter and, secondly to investigate the feasibility of using Fulmar and/or other potential species of seabird as an indicator for marine debris in Ireland through beached bird surveys. Within 30 months, 121 birds comprising 16 different species were collected and examined for the presence of litter. Of these, 27.3% (n = 33) comprising 12 different species were found to ingest litter, mainly plastics. The average mass of ingested litter was 0.141 g. Among 14 sampled Northern Fulmars, 13 (93%) had ingested plastic litter, all of them over the 0.1 g threshold used in OSPAR and MSFD policy target definitions. Results show that seabirds in Ireland are ingesting marine litter, as in many other countries in the world. Monitoring seabird litter ingestion has the potential to form part of a wider marine litter monitoring programme that can help to inform mitigation and management measures for marine litter. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. SOA Formation Potential of Emissions from Soil and Leaf Litter

    NASA Astrophysics Data System (ADS)

    Faiola, C. L.; Vanderschelden, G. S.; Wen, M.; Cobos, D. R.; Jobson, B. T.; VanReken, T. M.

    2013-12-01

    dominated by soil/litter emissions--soil/litter monoterpene emissions in spring could contribute up to 63% of total forest emissions. If this is the case, a significant portion of total forest monoterpene emission rates would be controlled by factors that affect soil/litter emissions rather than factors that affect plant emissions.

  13. Evaluating the effects of bedding materials and elevated platforms on contact dermatitis and plumage cleanliness of commercial broilers and on litter condition in broiler houses.

    PubMed

    Kaukonen, E; Norring, M; Valros, A

    2017-10-01

    1. Experiment 1, comparing wood shavings and ground straw bedding with peat, was performed on 7 broiler farms over two consecutive batches during the winter season. Experiment 2, assessing the effect of elevated (30 cm) platforms, was conducted in three farms replicated with 6 consecutive batches. 2. Footpad lesions were inspected at slaughter following the Welfare Quality® (WQ) assessment and official programme. Hock lesions, plumage cleanliness and litter condition were assessed using the WQ assessment. Litter height, pH, moisture and ammonia were determined. 3. Footpad condition on wood shavings appeared to be worse compared with peat using both methods of assessment and was accompanied by inferior hock skin health. WQ assessment resulted in poorer footpad and hock skin condition on ground straw compared with peat. Farms differed in footpad and hock skin condition. Footpad and hock lesions were not affected by platform treatment. Peat appeared more friable than ground straw. The initial pH of wood shavings was higher and moisture was lower than in peat, but at the end of production period there were no differences. Ground straw exhibited higher initial and lower end pH, and was drier in the beginning than peat. Litter condition and quality were not affected by platform treatment. 4. This study provides new knowledge about the applicability of peat as broiler bedding and shows no negative effects of elevated platforms on litter condition or the occurrence of contact dermatitis in commercial environments. The results suggest a complicated relationship between litter condition, moisture and contact dermatitis. Furthermore, it is concluded that the farmer's ability to manage litter conditions is important, regardless of the chosen litter material. Peat bedding was beneficial for footpad and hock skin health compared with wood shavings and ground straw.

  14. Distinct Microbial Limitations in Litter and Underlying Soil Revealed by Carbon and Nutrient Fertilization in a Tropical Rainforest

    PubMed Central

    Fanin, Nicolas; Barantal, Sandra; Fromin, Nathalie; Schimann, Heidy; Schevin, Patrick; Hättenschwiler, Stephan

    2012-01-01

    Human-caused alterations of the carbon and nutrient cycles are expected to impact tropical ecosystems in the near future. Here we evaluated how a combined change in carbon (C), nitrogen (N) and phosphorus (P) availability affects soil and litter microbial respiration and litter decomposition in an undisturbed Amazonian rainforest in French Guiana. In a fully factorial C (as cellulose), N (as urea), and P (as phosphate) fertilization experiment we analyzed a total of 540 litterbag-soil pairs after a 158-day exposure in the field. Rates of substrate-induced respiration (SIR) measured in litter and litter mass loss were similarly affected by fertilization showing the strongest stimulation when N and P were added simultaneously. The stimulating NP effect on litter SIR increased considerably with increasing initial dissolved organic carbon (DOC) concentrations in litter, suggesting that the combined availability of N, P, and a labile C source has a particularly strong effect on microbial activity. Cellulose fertilization, however, did not further stimulate the NP effect. In contrast to litter SIR and litter mass loss, soil SIR was reduced with N fertilization and showed only a positive effect in response to P fertilization that was further enhanced with additional C fertilization. Our data suggest that increased nutrient enrichment in the studied Amazonian rainforest can considerably change microbial activity and litter decomposition, and that these effects differ between the litter layer and the underlying soil. Any resulting change in relative C and nutrient fluxes between the litter layer and the soil can have important consequences for biogeochemical cycles in tropical forest ecosystems. PMID:23272052

  15. Broiler litter management effects on the nutrient composition of the litter

    USDA-ARS?s Scientific Manuscript database

    Application of poultry litter as a fertilizer source is a common practice in agriculture production. However, potential water quality concerns as a result of over application of poultry litter has risen as a major environmental issue in states with substantial poultry production. Fundamental to the ...

  16. Genetic Based Plant Resistance and Susceptibility Traits to Herbivory Influence Needle and Root Litter Nutrient Dynamics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Classen, Aimee T; Chapman, Samantha K.; Whitham, Thomas G

    2007-01-01

    It is generally assumed that leaf and root litter decomposition have similar drivers and that nutrient release from these substrates is synchronized. Few studies have examined these assumptions, and none has examined how plant genetics (i.e., plant susceptibility to herbivory) could affect these relationships. Here we examine the effects of herbivore susceptibility and resistance on needle and fine root litter decomposition of pi on pine, Pinus edulis. The study population consists of individual trees that are either susceptible or resistant to herbivory by the pi on needle scale, Matsucoccus acalyptus, or the stem-boring moth, Dioryctria albovittella. Genetic analyses and experimentalmore » removals and additions of these insects have identified trees that are naturally resistant and susceptible to these insects. These herbivores increase the chemical quality of litter inputs and alter soil microclimate, both of which are important decomposition drivers. Our research leads to four major conclusions: Herbivore susceptibility and resistance effects on 1) needle litter mass loss and phosphorus (P) retention in moth susceptible and resistant litter are governed by microclimate, 2) root litter nitrogen (N) and P retention, and needle litter N retention are governed by litter chemical quality, 3) net nutrient release from litter can reverse over time, 4) root and needle litter mass loss and nutrient release are determined by location (above- vs. belowground), suggesting that the regulators of needle and root decomposition differ at the local scale. Understanding of decomposition and nutrient retention in ecosystems requires consideration of herbivore effects on above- and belowground processes and how these effects may be governed by plant genotype. Because an underlying genetic component to herbivory is common to most ecosystems of the world and herbivory may increase in climatic change scenarios, it is important to evaluate the role of plant genetics in affecting

  17. Detection and quantification of ionophore antibiotics in runoff, soil and poultry litter.

    PubMed

    Sun, Peizhe; Barmaz, Delphine; Cabrera, Miguel L; Pavlostathis, Spyros G; Huang, Ching-Hua

    2013-10-18

    Ionophore antibiotics (IPAs) are widely used as coccidiostats in poultry and other livestock industries to promote growth and prevent infections. Because most of the ingested IPAs are excreted in poultry litter, which is primarily applied as grassland fertilizer, a significant amount of IPAs can be released into the litter-soil-water environment. A robust analytical method has been developed to quantify IPAs (monensin (MON), salinomycin (SAL) and narasin (NAR)) in complex environmental compartments including surface runoff, soil and poultry litter, with success to minimize matrix interference. The method for water samples involves solid-phase extraction (SPE) followed by liquid-liquid extraction (LLE) post-clean up steps. The method for solid samples involves bi-solvent LLE. IPAs were detected by HPLC-MS, with optimized parameters to achieve the highest sensitivity. Nigericin (NIG), an IPA not used in livestock industry, is successfully applied and validated as a surrogate standard. The method recoveries were at 92-95% and 81-85% in runoff samples from unfertilized and litter-fertilized fields, respectively. For solids, the method recoveries were at 93-99% in soils, and 79-83% in poultry litter samples. SAL was detected at up to 22mg/kg and MON and NAR at up to 4mg/kg in broiler litter from different farms. Up to 183μg/kg of MON was detected in litter-fertilized soils. All three IPAs were detected in the rainfall runoff from litter-fertilized lands at concentrations up to 9μg/L. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Inundation, vegetation, and sediment effects on litter decomposition in Pacific Coast tidal marshes

    USGS Publications Warehouse

    Janousek, Christopher; Buffington, Kevin J.; Guntenspergen, Glenn R.; Thorne, Karen M.; Dugger, Bruce D.; Takekawa, John Y.

    2017-01-01

    The cycling and sequestration of carbon are important ecosystem functions of estuarine wetlands that may be affected by climate change. We conducted experiments across a latitudinal and climate gradient of tidal marshes in the northeast Pacific to evaluate the effects of climate- and vegetation-related factors on litter decomposition. We manipulated tidal exposure and litter type in experimental mesocosms at two sites and used variation across marsh landscapes at seven sites to test for relationships between decomposition and marsh elevation, soil temperature, vegetation composition, litter quality, and sediment organic content. A greater than tenfold increase in manipulated tidal inundation resulted in small increases in decomposition of roots and rhizomes of two species, but no significant change in decay rates of shoots of three other species. In contrast, across the latitudinal gradient, decomposition rates of Salicornia pacifica litter were greater in high marsh than in low marsh. Rates were not correlated with sediment temperature or organic content, but were associated with plant assemblage structure including above-ground cover, species composition, and species richness. Decomposition rates also varied by litter type; at two sites in the Pacific Northwest, the grasses Deschampsia cespitosa and Distichlis spicata decomposed more slowly than the forb S. pacifica. Our data suggest that elevation gradients and vegetation structure in tidal marshes both affect rates of litter decay, potentially leading to complex spatial patterns in sediment carbon dynamics. Climate change may thus have direct effects on rates of decomposition through increased inundation from sea-level rise and indirect effects through changing plant community composition.

  19. Rain forest nutrient cycling and productivity in response to large-scale litter manipulation.

    PubMed

    Wood, Tana E; Lawrence, Deborah; Clark, Deborah A; Chazdon, Robin L

    2009-01-01

    from decomposing litter influences the magnitude. Seasonal or annual variation in leaf litter mass, such as occurs in strong El Niño events, could positively affect leaf litter nutrient cycling and forest productivity, indicating an ability of tropical trees to rapidly respond to increased nutrient availability.

  20. Plant structure predicts leaf litter capture in the tropical montane bromeliad Tillandsia turneri.

    PubMed

    Ospina-Bautista, F; Estévez Varón, J V

    2016-05-03

    Leaves intercepted by bromeliads become an important energy and matter resource for invertebrate communities, bacteria, fungi, and the plant itself. The relationship between bromeliad structure, defined as its size and complexity, and accumulated leaf litter was studied in 55 bromeliads of Tillandsia turneri through multiple regression and the Akaike information criterion. Leaf litter accumulation in bromeliads was best explained by size and complexity variables such as plant cover, sheath length, and leaf number. In conclusion, plant structure determines the amount of litter that enters bromeliads, and changes in its structure could affect important processes within ecosystem functioning or species richness.

  1. Climate history shapes contemporary leaf litter decomposition

    Treesearch

    Michael S. Strickland; Ashley D. Keiser; Mark A. Bradford

    2015-01-01

    Litter decomposition is mediated by multiple variables, of which climate is expected to be a dominant factor at global scales. However, like other organisms, traits of decomposers and their communities are shaped not just by the contemporary climate but also their climate history. Whether or not this affects decomposition rates is underexplored. Here we source...

  2. An evaluation of the presence of pathogens on broilers raised on poultry litter treatment-treated litter.

    PubMed

    Pope, M J; Cherry, T E

    2000-09-01

    Two trials were conducted to evaluate the presence of salmonella, campylobacter, and generic Escherichia coli on broilers raised on Poultry Litter Treatment (PLT)-enhanced litter in comparison with those raised on untreated litter. Two Company A farms included three houses on each farm as the treated group and three houses per farm as controls. Two complete growouts were evaluated on each farm. The Company B study included 10 farms with two paired houses per farm, one house as the treated group and one house as the control. One growout was evaluated per farm. The pathogen sampling consisted of litter sampling and whole bird rinses on the farm and in the processing plant. Litter pH, ammonia concentration, total litter bacteria, temperatures, and humidity were also recorded. The study with Company A resulted in lower mean levels of pH, ammonia concentration, total litter bacteria, litter E. coli, and bird rinse counts for salmonella and E. coli in houses treated with PLT. The results for Company B closely resembled those for Company A, but also included campylobacter data, which showed no difference between treated and control groups. The data indicate that PLT may be a beneficial component for on-farm pathogen reduction.

  3. Ecosystem and decomposer effects on litter dynamics along an old field to old-growth forest successional gradient

    NASA Astrophysics Data System (ADS)

    Mayer, Paul M.

    2008-03-01

    Identifying the biotic (e.g. decomposers, vegetation) and abiotic (e.g. temperature, moisture) mechanisms controlling litter decomposition is key to understanding ecosystem function, especially where variation in ecosystem structure due to successional processes may alter the strength of these mechanisms. To identify these controls and feedbacks, I measured mass loss and N flux in herbaceous, leaf, and wood litter along a successional gradient of ecosystem types (old field, transition forest, old-growth forest) while manipulating detritivore access to litter. Ecosystem type, litter type, and decomposers contributed directly and interactively to decomposition. Litter mass loss and N accumulation was higher while litter C:N remained lower in old-growth forests than in either old fields or transition forest. Old-growth forests influenced litter dynamics via microclimate (coolest and wettest) but also, apparently, through a decomposer community adapted to consuming the large standing stocks of leaf litter, as indicated by rapid leaf litter loss. In all ecosystem types, mass loss of herbaceous litter was greater than leaf litter which, in turn was greater than wood. However, net N loss from wood litter was faster than expected, suggesting localized N flux effects of wood litter. Restricting detritivore access to litter reduced litter mass loss and slowed the accumulation of N in litter, suggesting that macro-detritivores affect both physical and chemical characteristics of litter through selective grazing. These data suggest that the distinctive litter loss rates and efficient N cycling observed in old-growth forest ecosystems are not likely to be realized soon after old fields are restored to forested ecosystems.

  4. [Responses of soil microbial carbolic metabolism characteristics to home-field advantage of leaf litter decomposition in Liaoheyuan Nature Reserve of northern Hebei Province, China].

    PubMed

    Li, Tian-yu; Kang, Feng-feng; Han, Hai-rong; Gao, Jing; Song, Xiao-shuai; Yu, Shu

    2015-07-01

    Using litter bag method, we studied the responses of soil microbial biomass carbon (MBC), microbial respiration (MR) and microbial metabolic quotient (qCO2) in 0-5 cm, 5-10 cm and 10-20 cm soil layers to home-field advantage of Betula platyphlla and Quercus mongolica leaf litter decomposition in Liaoheyuan Nature Reserve, northern Hebei Province. The results showed that the contents of MBC in Betula platyphila and Quercus mongolica leaf litter treatments in home environment (Bh and Qh treatments) were significant higher than that in B. platyphlla and Q. mongolica leaf litter treatments in non-home environment (Ba and Qa treatments). There was no significant difference in MR between home and non-home environments. Response degree of MBC and MR to home-field advantage of different litter decomposition was inconsistent. The MBC of the different soil layers in Qa treatment fell by 39.6%, 34.9% and 33.5% compared to Qh treatment, respectively, and that in B. platyphlla treatment was decreased by 31.6%, 27.1% and 17.0%, respectively. MR of the different soil layers in Qa treatment accounted for 96.3%, 92.4% and 83.7% of Qh treatment, respectively, while MR in B. platyphila treatment was 99. 4%, 97. 3% and 101.3%, respectively. In contrast to MBC, qCO2 in soil showed a reverse pattern. Our study suggested that rich nutrients in soil enhanced microbial activity and weakened the conflict of nutrient uptake between plants and microorganisms, which led to the result that MBC and qCO2 had an obvious response to home-field advantage of litter decomposition, when litter decomposed in its home environment. There was a weak response between MR and home-field advantage of litter decomposition, because of influence of soil temperature, water content and their interaction. Furthermore, MBC, MR and qCO2 had a higher response degree to home-field advantage of Q. mongolica litter than B. platyphila litter, since lower quality litter exhibited higher home-field advantage of litter

  5. Interactions of tissue and fertilizer nitrogen on decomposition dynamics of lignin-rich conifer litter

    USGS Publications Warehouse

    Perakis, Steven S.; Matkins, Joselin J.; Hibbs, David E.

    2012-01-01

    High tissue nitrogen (N) accelerates decomposition of high-quality leaf litter in the early phases of mass loss, but the influence of initial tissue N variation on the decomposition of lignin-rich litter is less resolved. Because environmental changes such as atmospheric N deposition and elevated CO2 can alter tissue N levels within species more rapidly than they alter the species composition of ecosystems, it is important to consider how within-species variation in tissue N may shape litter decomposition and associated N dynamics. Douglas-fir (Pseudotsuga menziesii ) is a widespread lignin-rich conifer that dominates forests of high carbon (C) storage across western North America, and displays wide variation in tissue and litter N that reflects landscape variation in soil N. We collected eight unique Douglas-fir litter sources that spanned a two-fold range in initial N concentrations (0.67–1.31%) with a narrow range of lignin (29–35%), and examined relationships between initial litter chemistry, decomposition, and N dynamics in both ambient and N fertilized plots at four sites over 3 yr. High initial litter N slowed decomposition rates in both early (0.67 yr) and late (3 yr) stages in unfertilized plots. Applications of N fertilizer to litters accelerated early-stage decomposition, but slowed late-stage decomposition, and most strongly affected low-N litters, which equalized decomposition rates across litters regardless of initial N concentrations. Decomposition of N-fertilized litters correlated positively with initial litter manganese (Mn) concentrations, with litter Mn variation reflecting faster turnover of canopy foliage in high N sites, producing younger litterfall with high N and low Mn. Although both internal and external N inhibited decomposition at 3 yr, most litters exhibited net N immobilization, with strongest immobilization in low-N litter and in N-fertilized plots. Our observation for lignin-rich litter that high initial N can slow decomposition

  6. Through the sands of time: Beach litter trends from nine cleaned north cornish beaches.

    PubMed

    Watts, Andrew J R; Porter, Adam; Hembrow, Neil; Sharpe, Jolyon; Galloway, Tamara S; Lewis, Ceri

    2017-09-01

    Marine litter and its accumulation on beaches is an issue of major current concern due to its significant environmental and economic impacts. Yet our understanding of spatio-temporal trends in beach litter and the drivers of these trends are currently limited by the availability of robust long term data sets. Here we present a unique data set collected systematically once a month, every month over a six year period for nine beaches along the North Coast of Cornwall, U.K. to investigate the key drivers of beach litter in the Bude, Padstow and Porthcothan areas. Overall, an average of 0.02 litter items m -2 per month were collected during the six year study, with Bude beaches (Summerleaze, Crooklets and Widemouth) the most impacted (0.03 ± 0.004 litter items m -2 per month). The amount of litter collected each month decreased by 18% and 71% respectively for Padstow (Polzeath, Trevone and Harlyn) and Bude areas over the 6 years, possibly related to the regular cleaning, however litter increased by 120% despite this monthly cleaning effort on the Padstow area beaches. Importantly, at all nine beaches the litter was dominated by small, fragmented plastic pieces and rope fibres, which account for 32% and 17% of all litter items collected, respectively. The weathered nature of these plastics indicates they have been in the marine environment for an extended period of time. So, whilst classifying the original source of these plastics is not possible, it can be concluded they are not the result of recent public littering. This data highlights both the extent of the marine litter problem and that current efforts to reduce littering by beach users will only tackle a fraction of this litter. Such information is vital for developing effective management strategies for beach and marine litter at both regional and global levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. High-frequency fire alters C : N : P stoichiometry in forest litter.

    PubMed

    Toberman, Hannah; Chen, Chengrong; Lewis, Tom; Elser, James J

    2014-07-01

    Fire is a major driver of ecosystem change and can disproportionately affect the cycling of different nutrients. Thus, a stoichiometric approach to investigate the relationships between nutrient availability and microbial resource use during decomposition is likely to provide insight into the effects of fire on ecosystem functioning. We conducted a field litter bag experiment to investigate the long-term impact of repeated fire on the stoichiometry of leaf litter C, N and P pools, and nutrient-acquiring enzyme activities during decomposition in a wet sclerophyll eucalypt forest in Queensland, Australia. Fire frequency treatments have been maintained since 1972, including burning every 2 years (2yrB), burning every 4 years (4 yrB) and no burning (NB). C : N ratios in freshly fallen litter were 29-42% higher and C : P ratios were 6-25% lower for 2 yrB than NB during decomposition, with correspondingly lower 2yrB N : P ratios (27-32) than for NB (34-49). Trends in litter soluble and microbial N : P ratios were similar to the overall litter N : P ratios across fire treatments. Consistent with these, the ratio of activities for N-acquiring to P-acquiring enzymes in litter was higher for 2 yrB than NB, whereas 4 yrB was generally intermediate between 2 yrB and NB. Decomposition rates of freshly fallen litter were significantly lower for 2 yrB (72 ± 2% mass remaining at the end of experiment) than for 4 yrB (59 ± 3%) and NB (62 ± 3%), a difference that may be related to effects of N limitation, lower moisture content, and/or litter C quality. Results for older mixed-age litter were similar to those for freshly fallen litter although treatment differences were less pronounced. Overall, these findings show that frequent fire (2 yrB) decoupled N and P cycling, as manifested in litter C : N : P stoichiometry and in microbial biomass N : P ratio and enzymatic activities. Furthermore, these data indicate that fire induced a transient shift to N-limited ecosystem conditions

  8. Effects of multiple but low pesticide loads on aquatic fungal communities colonizing leaf litter.

    PubMed

    Talk, Anne; Kublik, Susanne; Uksa, Marie; Engel, Marion; Berghahn, Rüdiger; Welzl, Gerhard; Schloter, Michael; Mohr, Silvia

    2016-08-01

    In the first tier risk assessment (RA) of pesticides, risk for aquatic communities is estimated by using results from standard laboratory tests with algae, daphnids and fish for single pesticides such as herbicides, fungicides, and insecticides. However, fungi as key organisms for nutrient cycling in ecosystems as well as multiple pesticide applications are not considered in the RA. In this study, the effects of multiple low pesticide pulses using regulatory acceptable concentrations (RACs) on the dynamics of non-target aquatic fungi were investigated in a study using pond mesocosm. For that, fungi colonizing black alder (Alnus glutinosa) leaves were exposed to multiple, low pulses of 11 different pesticides over a period of 60days using a real farmer's pesticide application protocol for apple cropping. Four pond mesocosms served as treatments and 4 as controls. The composition of fungal communities colonizing the litter material was analyzed using a molecular fingerprinting approach based on the terminal Restriction Fragment Length Polymorphism (t-RFLP) of the fungal Internal Transcribed Spacer (ITS) region of the ribonucleic acid (RNA) gene(s). Our data indicated a clear fluctuation of fungal communities based on the degree of leaf litter degradation. However significant effects of the applied spraying sequence were not observed. Consequently also degradation rates of the litter material were not affected by the treatments. Our results indicate that the nutrient rich environment of the leaf litter material gave fungal communities the possibility to express genes that induce tolerance against the applied pesticides. Thus our data may not be transferred to other fresh water habitats with lower nutrient availability. Copyright © 2016. Published by Elsevier B.V.

  9. Insight into litter decomposition driven by nutrient demands of symbiosis system through the hypha bridge of arbuscular mycorrhizal fungi.

    PubMed

    Kong, Xiangshi; Jia, Yanyan; Song, Fuqiang; Tian, Kai; Lin, Hong; Bei, Zhanlin; Jia, Xiuqin; Yao, Bei; Guo, Peng; Tian, Xingjun

    2018-02-01

    Arbuscular mycorrhizal fungi (AMF) play an important role in litter decomposition. This study investigated how soil nutrient level affected the process. Results showed that AMF colonization had no significant effect on litter decomposition under normal soil nutrient conditions. However, litter decomposition was accelerated significantly under lower nutrient conditions. Soil microbial biomass in decomposition system was significantly increased. Especially, in moderate lower nutrient treatment (condition of half-normal soil nutrient), litters exhibited the highest decomposition rate, AMF hypha revealed the greatest density, and enzymes (especially nitrate reductase) showed the highest activities as well. Meanwhile, the immobilization of nitrogen (N) in the decomposing litter remarkably decreased. Our results suggested that the roles AMF played in ecosystem were largely affected by soil nutrient levels. At normal soil nutrient level, AMF exhibited limited effects in promoting decomposition. When soil nutrient level decreased, the promoting effect of AMF on litter decomposition began to appear, especially on N mobilization. However, under extremely low nutrient conditions, AMF showed less influence on decomposition and may even compete with decomposer microorganisms for nutrients.

  10. Degradation of polycyclic aromatic hydrocarbons (PAHs) during Sphagnum litters decay.

    PubMed

    Wang, Zucheng; Liu, Shasha; Bu, Zhao-Jun; Wang, Shengzhong

    2018-04-28

    The dynamics of polycyclic aromatic hydrocarbon (PAH) degradation in Sphagnum litters and the decomposition of the litters were investigated. PAH concentration decreased to approximately half of the initial concentration as Sphagnum litters decayed. The initial PAH concentration was 489.2 ± 72.2 ng g -1 , and the concentration after 120 days of incubation was 233.0 ± 5.8 ng g -1 . The different PAH compositions changed concentrations at different times. The low-molecular-weight (LMW) and high-molecular-weight (HMW) PAHs started to be degraded after incubation and after 40 days of incubation, respectively. PAH concentrations in the Sphagnum litters correlated with the total organic carbon (TOC) content (p < 0.05), indicating that PAHs were associated with the TOC of the Sphagnum litters and were degraded as organic matter decayed. The positive relationship between LMW PAH concentration and the soluble carbohydrate content (p < 0.05) indicated that LMW PAHs and the readily decomposed organic carbon fractions were cometabolized, or that LMW PAHs were mainly absorbed by soluble carbohydrate. The weak negative correlation between fulvic acid (FA) and PAH concentrations (p < 0.1) indicated that FA may enhance PAH degradation. Redundancy analysis suggested that the contents of both soluble carbohydrate and cellulose significantly affected the changes in PAH concentrations (p < 0.05), and that FA content and C/N ratios may also contribute to the changes in PAH concentrations (p < 0.1). However, the polyphenol that was related to microbial activities was not associated with changes in PAH concentrations. These results suggested that litter quality is more important than microbial activities in PAH degradation in Sphagnum litters.

  11. Parents and Early Life Environment Affect Behavioral Development of Laying Hen Chickens

    PubMed Central

    de Haas, Elske N.; Bolhuis, J. Elizabeth; Kemp, Bas; Groothuis, Ton G. G.; Rodenburg, T. Bas

    2014-01-01

    Severe feather pecking (SFP) in commercial laying hens is a maladaptive behavior which is associated with anxiety traits. Many experimental studies have shown that stress in the parents can affect anxiety in the offspring, but until now these effects have been neglected in addressing the problem of SFP in commercially kept laying hens. We therefore studied whether parental stock (PS) affected the development of SFP and anxiety in their offspring. We used flocks from a brown and white genetic hybrid because genetic background can affect SFP and anxiety. As SFP can also be influenced by housing conditions on the rearing farm, we included effects of housing system and litter availability in the analysis. Forty-seven rearing flocks, originating from ten PS flocks were followed. Behavioral and physiological parameters related to anxiety and SFP were studied in the PS at 40 weeks of age and in the rearing flocks at one, five, ten and fifteen weeks of age. We found that PS had an effect on SFP at one week of age and on anxiety at one and five weeks of age. In the white hybrid, but not in the brown hybrid, high levels of maternal corticosterone, maternal feather damage and maternal whole-blood serotonin levels showed positive relations with offsprings’ SFP at one week and offsprings’ anxiety at one and five weeks of age. Disruption and limitation of litter supply at an early age on the rearing farms increased SFP, feather damage and fearfulness. These effects were most prominent in the brown hybrid. It appeared that hens from a brown hybrid are more affected by environmental conditions, while hens from a white hybrid were more strongly affected by parental effects. These results are important for designing measures to prevent the development of SFP, which may require a different approach in brown and white flocks. PMID:24603500

  12. Riparian plant litter quality increases with latitude.

    PubMed

    Boyero, Luz; Graça, Manuel A S; Tonin, Alan M; Pérez, Javier; J Swafford, Andrew; Ferreira, Verónica; Landeira-Dabarca, Andrea; A Alexandrou, Markos; Gessner, Mark O; McKie, Brendan G; Albariño, Ricardo J; Barmuta, Leon A; Callisto, Marcos; Chará, Julián; Chauvet, Eric; Colón-Gaud, Checo; Dudgeon, David; Encalada, Andrea C; Figueroa, Ricardo; Flecker, Alexander S; Fleituch, Tadeusz; Frainer, André; Gonçalves, José F; Helson, Julie E; Iwata, Tomoya; Mathooko, Jude; M'Erimba, Charles; Pringle, Catherine M; Ramírez, Alonso; Swan, Christopher M; Yule, Catherine M; Pearson, Richard G

    2017-09-05

    Plant litter represents a major basal resource in streams, where its decomposition is partly regulated by litter traits. Litter-trait variation may determine the latitudinal gradient in decomposition in streams, which is mainly microbial in the tropics and detritivore-mediated at high latitudes. However, this hypothesis remains untested, as we lack information on large-scale trait variation for riparian litter. Variation cannot easily be inferred from existing leaf-trait databases, since nutrient resorption can cause traits of litter and green leaves to diverge. Here we present the first global-scale assessment of riparian litter quality by determining latitudinal variation (spanning 107°) in litter traits (nutrient concentrations; physical and chemical defences) of 151 species from 24 regions and their relationships with environmental factors and phylogeny. We hypothesized that litter quality would increase with latitude (despite variation within regions) and traits would be correlated to produce 'syndromes' resulting from phylogeny and environmental variation. We found lower litter quality and higher nitrogen:phosphorus ratios in the tropics. Traits were linked but showed no phylogenetic signal, suggesting that syndromes were environmentally determined. Poorer litter quality and greater phosphorus limitation towards the equator may restrict detritivore-mediated decomposition, contributing to the predominance of microbial decomposers in tropical streams.

  13. Temporal dynamics of phosphorus during aquatic and terrestrial litter decomposition in an alpine forest.

    PubMed

    Peng, Yan; Yang, Wanqin; Yue, Kai; Tan, Bo; Huang, Chunping; Xu, Zhenfeng; Ni, Xiangyin; Zhang, Li; Wu, Fuzhong

    2018-06-17

    Plant litter decomposition in forested soil and watershed is an important source of phosphorus (P) for plants in forest ecosystems. Understanding P dynamics during litter decomposition in forested aquatic and terrestrial ecosystems will be of great importance for better understanding nutrient cycling across forest landscape. However, despite massive studies addressing litter decomposition have been carried out, generalizations across aquatic and terrestrial ecosystems regarding the temporal dynamics of P loss during litter decomposition remain elusive. We conducted a two-year field experiment using litterbag method in both aquatic (streams and riparian zones) and terrestrial (forest floors) ecosystems in an alpine forest on the eastern Tibetan Plateau. By using multigroup comparisons of structural equation modeling (SEM) method with different litter mass-loss intervals, we explicitly assessed the direct and indirect effects of several biotic and abiotic drivers on P loss across different decomposition stages. The results suggested that (1) P concentration in decomposing litter showed similar patterns of early increase and later decrease across different species and ecosystems types; (2) P loss shared a common hierarchy of drivers across different ecosystems types, with litter chemical dynamics mainly having direct effects but environment and initial litter quality having both direct and indirect effects; (3) when assessing at the temporal scale, the effects of initial litter quality appeared to increase in late decomposition stages, while litter chemical dynamics showed consistent significant effects almost in all decomposition stages across aquatic and terrestrial ecosystems; (4) microbial diversity showed significant effects on P loss, but its effects were lower compared with other drivers. Our results highlight the importance of including spatiotemporal variations and indicate the possibility of integrating aquatic and terrestrial decomposition into a common

  14. Decomposition and nitrogen dynamics of 15N-labeled leaf, root, and twig litter in temperate coniferous forests

    USGS Publications Warehouse

    van Huysen, Tiff L.; Harmon, Mark E.; Perakis, Steven S.; Chen, Hua

    2013-01-01

    Litter nutrient dynamics contribute significantly to biogeochemical cycling in forest ecosystems. We examined how site environment and initial substrate quality influence decomposition and nitrogen (N) dynamics of multiple litter types. A 2.5-year decomposition study was installed in the Oregon Coast Range and West Cascades using 15N-labeled litter from Acer macrophyllum, Picea sitchensis, and Pseudotsuga menziesii. Mass loss for leaf litter was similar between the two sites, while root and twig litter exhibited greater mass loss in the Coast Range. Mass loss was greatest from leaves and roots, and species differences in mass loss were more prominent in the Coast Range. All litter types and species mineralized N early in the decomposition process; only A. macrophyllum leaves exhibited a net N immobilization phase. There were no site differences with respect to litter N dynamics despite differences in site N availability, and litter N mineralization patterns were species-specific. For multiple litter × species combinations, the difference between gross and net N mineralization was significant, and gross mineralization was 7–20 % greater than net mineralization. The mineralization results suggest that initial litter chemistry may be an important driver of litter N dynamics. Our study demonstrates that greater amounts of N are cycling through these systems than may be quantified by only measuring net mineralization and challenges current leaf-based biogeochemical theory regarding patterns of N immobilization and mineralization.

  15. Interaction of initial litter quality and thinning intensity on litter decomposition rate, nitrogen accumulation and release in a pine plantation

    Treesearch

    Xiao Chen; Deborah Page-Dumroese; Ruiheng Lv; Weiwei Wang; Guolei Li; Yong Liu

    2014-01-01

    Thinning alters litter quality and microclimate under forests. Both of these two changes after thinning induce alterations of litter decomposition rates and nutrient cycling. However, a possible interaction between these two changes remains unclear. We placed two types of litter (LN, low N concentration litter; HN, high N concentration litter) in a Chinese pine (Pinus...

  16. Development of piglets raised in a new multi-litter housing system vs. conventional single-litter housing until 9 weeks of age.

    PubMed

    van Nieuwamerongen, S E; Soede, N M; van der Peet-Schwering, C M C; Kemp, B; Bolhuis, J E

    2015-11-01

    This study compared the development until 9 wk of age of piglets raised in either a multi-litter (ML) system or a conventional single-litter (SL) system. The ML system consisted of a multi-suckling system with 5 sows and their litters before weaning, followed by housing in a pen with enrichment in a group of 40 piglets after weaning. In the SL system, piglets were housed with a crated sow before weaning, followed by postweaning housing in groups of 10 littermates in a standard pen. Fifty litters were used in 5 batches and piglets were weaned at 4 wk of age. Preweaning mortality was higher in the ML system than in the SL system (3.22 ± 0.42 vs. 1.52 ± 0.25 piglets per litter, < 0.01), mainly due to crushing before grouping of litters. Litter size at grouping did not differ between systems. ML piglets showed more feed-directed behavior at 2 wk of age (6.80 ± 0.96 vs. 2.35 ± 0.59, < 0.01), suggesting an earlier start of feed exploration, possibly due to social learning from the floor-fed sows and other piglets. Moreover, before weaning, ML piglets showed less damaging oral manipulation (e.g., tail biting) than SL piglets (1.4 ± 0.2 vs. 3.6 ± 0.3 freq/h, < 0.001), which was likely related to the more enriched environment in the ML system. After weaning, ML piglets ate 81% more feed between d 1 and 2 (0.29 ± 0.02 vs. 0.16 ± 0.03 kg/piglet, < 0.01) and had an 82% higher weight gain until d 5 than SL piglets (1.35 ± 0.21 vs. 0.75 ± 0.17 kg, < 0.05) despite a similar weaning weight (ML: 8.4 ± 0.2 kg, SL: 8.3 ± 0.2 kg). Within the first 2 wk after weaning, ML piglets had a lower fecal consistency score (0.27 ± 0.03 vs. 0.39 ± 0.03, < 0.05), indicating a lower occurrence of diarrhea compared with SL piglets. Over the entire 5-wk postweaning phase, ML piglets had a 24% higher weight gain ( < 0.05) and showed more play behavior (4.0 ± 0.3 vs. 2.8 ± 0.3 freq/h, < 0.05) and less damaging oral manipulation (1.8 ± 0.3 vs. 3.5 ± 0.4 freq/h, < 0.01) than SL piglets

  17. Microbial plant litter decomposition in aquatic and terrestrial boreal systems along a natural fertility gradient

    NASA Astrophysics Data System (ADS)

    Soares, A. Margarida P. M.; Kritzberg, Emma S.; Rousk, Johannes

    2017-04-01

    Plant litter decomposition is a global ecosystem process, with a crucial role in carbon and nutrient cycling. The majority of litter processing occurs in terrestrial systems, but an important fraction also takes place in inland waters. Among environmental factors, pH impacts the litter decomposition through its selective influence on microbial decomposers. Fungal communities are less affected by pH than bacteria, possibly owing to a wider pH tolerance by this group. On the other hand, bacterial pH optima are constrained to a narrower range of pH values. The microbial decomposition of litter is universally nutrient limited; but few comparisons exist between terrestrial and aquatic systems. We investigated the microbial colonisation and decomposition of plant litter along a fertility gradient, which varied in both pH and N availability in both soil and adjacent water. To do this we installed litterbags with birch (Betula pendula) in streams and corresponding soils in adjacent riparian areas in a boreal system, in Krycklan, Sweden. During the four months covering the ice-free growth season we monitored the successional dynamics of fungal (acetate incorporation into ergosterol) and bacterial growth (thymidine incorporation), microbial respiration in leaf litter, and quantitative and qualitative changes in litter over time. We observed that bacterial growth rates were initially higher in litter decomposing in streams than those in soils, but differences between terrestrial and aquatic bacterial production converged towards the end of the experiment. In litter bags installed in soils, bacterial growth was lower at sites with more acidic pH and lower N availability, while aquatic bacteria were relatively unaffected by the fertility level. Fungal growth rates were two-fold higher for litter decomposing in streams than in soils. In aquatic systems, fungal growth was initially lower in low fertility sites, but differences gradually disappeared over the time course. Fungal

  18. Tea polyphenols dominate the short-term tea (Camellia sinensis) leaf litter decomposition*

    PubMed Central

    Fan, Dong-mei; Fan, Kai; Yu, Cui-ping; Lu, Ya-ting; Wang, Xiao-chang

    2017-01-01

    Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography (HPLC) and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid (GA), catechin gallate (CG), and gallocatechin (GC) were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols. PMID:28124839

  19. Tea polyphenols dominate the short-term tea (Camellia sinensis) leaf litter decomposition.

    PubMed

    Fan, Dong-Mei; Fan, Kai; Yu, Cui-Ping; Lu, Ya-Ting; Wang, Xiao-Chang

    Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography (HPLC) and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid (GA), catechin gallate (CG), and gallocatechin (GC) were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols.

  20. Decomposition rate of Rhizopora stylosa litter in Tanjung Rejo Village, Deli Serdang Regency, North Sumatera Province

    NASA Astrophysics Data System (ADS)

    Rambey, R.; Delvian; Sianturi, S. D.

    2018-02-01

    Research on the decomposition rate of Rhizopora stylosa litter in Tanjung Rejo village, Deli Serdang Regency, North Sumatera Province was conducted from September 2016 to May 2017. The objectives of this research were (1) to measure the decomposition rate of Rhizophora stylosa litter and (2) to determine the type of functional fungi in decomposition of litter. R. stylosa litter decomposition is characterized by a reduction in litter weight per observation period. Decomposition rate tended to increase every week, which was from 0.238 in the seventh day and reached 0.302 on the fiftysixthth day. The decomposition rate of R. stylosa litter of leaf was high with the value of k per day > 0,01 caused by macrobentos and fungi, and also the decomposition of R. stylosa litter conducted in the pond area which is classified far from the coast. Therefore, to enable the high population of fungi which affect the decomposition rate of the litter. The types of fungi decomposers were: Aspergillus sp.-1, Aspergillus sp.-2, Aspergillus sp.-3, Rhizophus sp.-1., Rhizophus sp.-2, Penicillium sp., Syncephalastrum sp. and Fusarium sp.

  1. Decomposition and nitrogen dynamics of 15N-labeled leaf, root, and twig litter in temperate coniferous forests

    Treesearch

    T.L. van Huysen; M.E. Harmon; S.S. Perakis; H. Chen

    2013-01-01

    Litter nutrient dynamics contribute significantly to biogeochemical cycling in forest ecosystems. We examined how site environment and initial substrate quality influence decomposition and nitrogen (N) dynamics of multiple litter types. A 2.5-year decomposition study was installed in the Oregon Coast Range and West Cascades using 15N-labeled...

  2. Plant species traits are the predominant control on litter decomposition rates within biomes worldwide.

    PubMed

    Cornwell, William K; Cornelissen, Johannes H C; Amatangelo, Kathryn; Dorrepaal, Ellen; Eviner, Valerie T; Godoy, Oscar; Hobbie, Sarah E; Hoorens, Bart; Kurokawa, Hiroko; Pérez-Harguindeguy, Natalia; Quested, Helen M; Santiago, Louis S; Wardle, David A; Wright, Ian J; Aerts, Rien; Allison, Steven D; van Bodegom, Peter; Brovkin, Victor; Chatain, Alex; Callaghan, Terry V; Díaz, Sandra; Garnier, Eric; Gurvich, Diego E; Kazakou, Elena; Klein, Julia A; Read, Jenny; Reich, Peter B; Soudzilovskaia, Nadejda A; Vaieretti, M Victoria; Westoby, Mark

    2008-10-01

    Worldwide decomposition rates depend both on climate and the legacy of plant functional traits as litter quality. To quantify the degree to which functional differentiation among species affects their litter decomposition rates, we brought together leaf trait and litter mass loss data for 818 species from 66 decomposition experiments on six continents. We show that: (i) the magnitude of species-driven differences is much larger than previously thought and greater than climate-driven variation; (ii) the decomposability of a species' litter is consistently correlated with that species' ecological strategy within different ecosystems globally, representing a new connection between whole plant carbon strategy and biogeochemical cycling. This connection between plant strategies and decomposability is crucial for both understanding vegetation-soil feedbacks, and for improving forecasts of the global carbon cycle.

  3. Factors influencing leaf litter decomposition: An intersite decomposition experiment across China

    USGS Publications Warehouse

    Zhou, G.; Guan, L.; Wei, X.; Tang, X.; Liu, S.; Liu, J.; Zhang, Dongxiao; Yan, J.

    2008-01-01

    The Long-Term Intersite Decomposition Experiment in China (hereafter referred to as LTIDE-China) was established in 2002 to study how substrate quality and macroclimate factors affect leaf litter decomposition. The LTIDE-China includes a wide variety of natural and managed ecosystems, consisting of 12 forest types (eight regional broadleaf forests, three needle-leaf plantations and one broadleaf plantation) at eight locations across China. Samples of mixed leaf litter from the south subtropical evergreen broadleaf forest in Dinghushan (referred to as the DHS sample) were translocated to all 12 forest types. The leaf litter from each of other 11 forest types was placed in its original forest to enable comparison of decomposition rates of DHS and local litters. The experiment lasted for 30 months, involving collection of litterbags from each site every 3 months. Our results show that annual decomposition rate-constants, as represented by regression fitted k-values, ranged from 0.169 to 1.454/year. Climatic factors control the decomposition rate, in which mean annual temperature and annual actual evapotranspiration are dominant and mean annual precipitation is subordinate. Initial C/N and N/P ratios were demonstrated to be important factors of regulating litter decomposition rate. Decomposition process may apparently be divided into two phases controlled by different factors. In our study, 0.75 years is believed to be the dividing line of the two phases. The fact that decomposition rates of DHS litters were slower than those of local litters may have been resulted from the acclimation of local decomposer communities to extraneous substrate. ?? 2008 Springer Science+Business Media B.V.

  4. Environmentally friendly animal litter

    DOEpatents

    Chett, Boxley; McKelvie, Jessica

    2013-08-20

    A method of making an animal litter that includes geopolymerized ash, wherein, the animal litter is made from a quantity of a pozzolanic ash mixed with a sufficient quantity of water and an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. After the geopolymerized ash is formed, it is dried, broken into particulates, and sieved to a desired size. These geopolymerized ash particulates are used to make a non-clumping or clumping animal litter. Odor control may be accomplished with the addition of a urease inhibitor, pH buffer, an odor eliminating agent, and/or fragrance.

  5. Beach litter occurrence in sandy littorals: The potential role of urban areas, rivers and beach users in central Italy

    NASA Astrophysics Data System (ADS)

    Poeta, Gianluca; Conti, Luisa; Malavasi, Marco; Battisti, Corrado; Acosta, Alicia Teresa Rosario

    2016-11-01

    Litter washed ashore on the coastline, also called beach litter, constitutes one of the most obvious signs of marine litter pollution. Surveys of beach litter represent a fundamental tool for monitoring pollution in the marine environment and have been used world-wide to classify and quantify marine litter. Identifying the sources of marine and beach litter is, together with education, the prime weapon in combating this type of pollution. This work investigates the impact of three main potential land sources on litter occurrence: urban areas, rivers and beach users. Three sources were analyzed simultaneously on a broad scale (Lazio region, central Italy) using a random sampling design and fitting a generalized linear mixed-effect model. The results show that urban areas are the main drivers for the occurrence of marine litter along central Italy's coastal ecosystems, suggesting that the presence of such litter on Lazio beaches could be effectively reduced by identifying failings in recycling and waste collection procedures and by improving waste processing systems and sewage treatment in urban areas.

  6. The effect of leaf litter cover on surface runoff and soil erosion in Northern China.

    PubMed

    Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

    2014-01-01

    The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter), four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (p<0.05). Average runoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, p<0.05), and the efficiency in runoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h-1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05) were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (p<0.05) with sediment yield. These results suggest that the protective role of leaf litter in runoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes.

  7. The Effect of Leaf Litter Cover on Surface Runoff and Soil Erosion in Northern China

    PubMed Central

    Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

    2014-01-01

    The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter), four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (p<0.05). Average runoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, p<0.05), and the efficiency in runoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h−1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05) were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (p<0.05) with sediment yield. These results suggest that the protective role of leaf litter in runoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes. PMID:25232858

  8. Land use not litter quality is a stronger driver of decomposition in hyperdiverse tropical forest.

    PubMed

    Both, Sabine; Elias, Dafydd M O; Kritzler, Ully H; Ostle, Nick J; Johnson, David

    2017-11-01

    In hyperdiverse tropical forests, the key drivers of litter decomposition are poorly understood despite its crucial role in facilitating nutrient availability for plants and microbes. Selective logging is a pressing land use with potential for considerable impacts on plant-soil interactions, litter decomposition, and nutrient cycling. Here, in Borneo's tropical rainforests, we test the hypothesis that decomposition is driven by litter quality and that there is a significant "home-field advantage," that is positive interaction between local litter quality and land use. We determined mass loss of leaf litter, collected from selectively logged and old-growth forest, in a fully factorial experimental design, using meshes that either allowed or precluded access by mesofauna. We measured leaf litter chemical composition before and after the experiment. Key soil chemical and biological properties and microclimatic conditions were measured as land-use descriptors. We found that despite substantial differences in litter quality, the main driver of decomposition was land-use type. Whilst inclusion of mesofauna accelerated decomposition, their effect was independent of land use and litter quality. Decomposition of all litters was slower in selectively logged forest than in old-growth forest. However, there was significantly greater loss of nutrients from litter, especially phosphorus, in selectively logged forest. The analyses of several covariates detected minor microclimatic differences between land-use types but no alterations in soil chemical properties or free-living microbial composition. These results demonstrate that selective logging can significantly reduce litter decomposition in tropical rainforest with no evidence of a home-field advantage. We show that loss of key limiting nutrients from litter (P & N) is greater in selectively logged forest. Overall, the findings hint at subtle differences in microclimate overriding litter quality that result in reduced

  9. Environmental fate of roxarsone in poultry litter. I. Degradation of roxarsone during composting

    USGS Publications Warehouse

    Garbarino, J.R.; Bednar, A.J.; Rutherford, D.W.; Beyer, R.S.; Wershaw, R. L.

    2003-01-01

    Roxarsone, 3-nitro-4-hydroxyphenylarsonic acid, is an organoarsenic compound that is used extensively in the feed of broiler poultryto control coccidial intestinal parasites, improve feed efficiency, and promote rapid growth. Nearly all the roxarsone in the feed is excreted unchanged in the manure. Poultry litter composed of the manure and bedding material has a high nutrient content and is used routinely as a fertilizer on cropland and pasture. Investigations were conducted to determine the fate of poultrylitter roxarsone in the environment. Experiments indicated that roxarsone was stable in fresh dried litter; the primary arsenic species extracted with water from dried litter was roxarsone. However, when water was added to litter at about 50 wt % and the mixture was allowed to compost at 40oC, the speciation of arsenic shifted from roxarsone to primarily arsenate in about 30 days. Increasing the amount of water increased the rate of degradation. Experiments also suggested that the degradation process most likely was biotic in nature. The rate of degradation was directly proportional to the incubation temperature; heat sterilization eliminated the degradation. Biotic degradation also was supported by results from enterobacteriaceae growth media that were inoculated with litter slurry to enhance the biotic processes and to reduce the concomitant abiotic effects from the complex litter solution. Samples collected from a variety of litter windrows in Arkansas, Oklahoma, and Maryland also showed that roxarsone originally present had been converted to arsenate.

  10. Quality of soluble organic C, N, and P produced by different types and species of litter: root litter versus leaf litter

    USDA-ARS?s Scientific Manuscript database

    In forested ecosystems, the quality of dissolved organic matter (DOM) produced by freshly senesced litter may differ by litter type and species, and these differences may influence the amount of DOM that is respired versus that which may either contribute to soil organic matter accumulation or be le...

  11. Leaf litter decomposition and elemental change in three Appalachian mountain streams of different pH

    Treesearch

    Steven W. Solada; Sue A. Perry; William B. Perry

    1996-01-01

    The decomposition of leaf litter provides the primary nutrient source for many of the headwater mountain streams in forested catchments. An investigation of factors affected by global change that influence organic matter decomposition, such as temperature and pH, is important in understanding the dynamics of these systems. We conducted a study of leaf litter elemental...

  12. Maternal-Neonatal Pheromone/Interomone Added to Cat Litter Improves Litter Box Use and Reduces Aggression in Pair-Housed Cats.

    PubMed

    McGlone, John J; Garcia, Arlene; Thompson, William G; Pirner, Glenna M

    2018-03-27

    Introducing a new cat into a household with one or more resident cats can be a significant source of stress for the cats involved. These studies sought to determine if rabbit maternal-neonatal pheromone (2-methyl-2-butenal [2M2B]) in litter impacted cat social behaviors and litter box use. Study 1 determined that cats preferred to eliminate in litter containing 2M2B; other semiochemicals tested did not change litter box use. Cats prone to aggression were identified in an intermediate pilot study, and eight pairs of these cats were selected for Study 2. In Study 2, cat pairs were provided litter containing either vehicle or 2M2B for 24 hours. Cats experiencing control litter displayed more aggression during the first 6 hours (p < .01) and spent more time using the litter box 12 hours and 18 hours after pairing compared with cats experiencing litter with 2M2B (p = .02). These results suggest 2M2B-infused cat litter may act as an interomone in cats housed domestically to prevent initial occurrences of aggression and may improve cat welfare in multicat households.

  13. Species diversity and chemical properties of litter influence non-additive effects of litter mixtures on soil carbon and nitrogen cycling

    PubMed Central

    Mao, Bing; Mao, Rong; Zeng, De-Hui

    2017-01-01

    Decomposition of litter mixtures generally cannot be predicted from the component species incubated in isolation. Therefore, such non-additive effects of litter mixing on soil C and N dynamics remain poorly understood in terrestrial ecosystems. In this study, litters of Mongolian pine and three dominant understory species and soil were collected from a Mongolian pine plantation in Northeast China. In order to examine the effects of mixed-species litter on soil microbial biomass N, soil net N mineralization and soil respiration, four single litter species and their mixtures consisting of all possible 2-, 3- and 4-species combinations were added to soils, respectively. In most instances, species mixing produced synergistic non-additive effects on soil microbial biomass N and soil respiration, but antagonistic non-additive effects on net N mineralization. Species composition rather than species richness explained the non-additive effects of species mixing on soil microbial biomass N and net N mineralization, due to the interspecific differences in litter chemical composition. Both litter species composition and richness explained non-additive soil respiration responses to mixed-species litter, while litter chemical diversity and chemical composition did not. Our study indicated that litter mixtures promoted soil microbial biomass N and soil respiration, and inhibited net N mineralization. Soil N related processes rather than soil respiration were partly explained by litter chemical composition and chemical diversity, highlighting the importance of functional diversity of litter on soil N cycling. PMID:28686660

  14. Species diversity and chemical properties of litter influence non-additive effects of litter mixtures on soil carbon and nitrogen cycling.

    PubMed

    Mao, Bing; Mao, Rong; Zeng, De-Hui

    2017-01-01

    Decomposition of litter mixtures generally cannot be predicted from the component species incubated in isolation. Therefore, such non-additive effects of litter mixing on soil C and N dynamics remain poorly understood in terrestrial ecosystems. In this study, litters of Mongolian pine and three dominant understory species and soil were collected from a Mongolian pine plantation in Northeast China. In order to examine the effects of mixed-species litter on soil microbial biomass N, soil net N mineralization and soil respiration, four single litter species and their mixtures consisting of all possible 2-, 3- and 4-species combinations were added to soils, respectively. In most instances, species mixing produced synergistic non-additive effects on soil microbial biomass N and soil respiration, but antagonistic non-additive effects on net N mineralization. Species composition rather than species richness explained the non-additive effects of species mixing on soil microbial biomass N and net N mineralization, due to the interspecific differences in litter chemical composition. Both litter species composition and richness explained non-additive soil respiration responses to mixed-species litter, while litter chemical diversity and chemical composition did not. Our study indicated that litter mixtures promoted soil microbial biomass N and soil respiration, and inhibited net N mineralization. Soil N related processes rather than soil respiration were partly explained by litter chemical composition and chemical diversity, highlighting the importance of functional diversity of litter on soil N cycling.

  15. Arsenic speciation and reactivity in poultry litter

    USGS Publications Warehouse

    Arai, Y.; Lanzirotti, A.; Sutton, S.; Davis, J.A.; Sparks, D.L.

    2003-01-01

    Recent U.S. government action to lower the maximum concentration levels (MCL) of total arsenic (As) (10 ppb) in drinking water has raised serious concerns about the agricultural use of As-containing biosolids such as poultry litter (PL). In this study, solid-state chemical speciation, desorbability, and total levels of As in PL and long-term amended soils were investigated using novel synchrotronbased probing techniques (microfocused (??) synchrotron X-ray fluorescence (SXRF) and ??-X-ray absorption near-edge structure (XANES) spectroscopies) coupled with chemical digestion and batch experiments. The total As levels in the PL were as high as ???50 mg kg-1, and As(II/III and V) was always concentrated in abundant needle-shaped microscopic particles (???20/ ??m x 850 ??m) associated with Ca, Cu, and Fe and to a lesser extent with S, CI, and Zn. Postedge XANES features of litter particles are dissimilar to those of the organo-As(V) compound in poultry feed (i.e., roxarsone), suggesting possible degradation/transformation of roxarsone in the litter and/or in poultry digestive tracts. The extent of As desorption from the litter increased with increasing time and pH from 4.5 to 7, but at most 15% of the total As was released after 5 d at pH 7, indicating the presence of insoluble phases and/or strongly retained soluble compounds. No significant As accumulation (< 15 mg kg-1) was found in long-term PL-a mended agricultural surface soils. This suggests that As in the PL may have undergone surface and subsurface transport processes. Our research results raise concerns about long-term PL amendment effects on As contamination in surrounding soilwater environments.

  16. Increased plastic litter cover affects the foraging activity of the sandy intertidal gastropod Nassarius pullus.

    PubMed

    Aloy, Alexander B; Vallejo, Benjamin M; Juinio-Meñez, Marie Antonette

    2011-08-01

    This study analyzed the foraging behavior of the gastropod Nassarius pullus on garbage-impacted sandy shores of Talim Bay, Batangas, Philippines. The effect of different levels of plastic garbage cover on foraging efficiency was investigated. Controlled in situ baiting experiments were conducted to quantify aspects of foraging behavior as affected by the levels of plastic litter cover in the foraging area. The results of the study indicated that the gastropod's efficiency in locating and in moving towards a food item generally decreased as the level of plastic cover increased. Prolonged food searching time and increased self-burial in sand were highly correlated with increased plastic cover. The accuracy of orientation towards the actual position of the bait decreased significantly when the amount of plastic cover increased to 50%. These results are consistent with the significant decreases in the abundance of the gastropod observed during periods of deposition of large amounts of plastic and other debris on the shore. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Shrub encroachment in Arctic tundra: Betula nana effects on above- and belowground litter decomposition.

    PubMed

    McLaren, Jennie R; Buckeridge, Kate M; van de Weg, Martine J; Shaver, Gaius R; Schimel, Joshua P; Gough, Laura

    2017-05-01

    Rapid arctic vegetation change as a result of global warming includes an increase in the cover and biomass of deciduous shrubs. Increases in shrub abundance will result in a proportional increase of shrub litter in the litter community, potentially affecting carbon turnover rates in arctic ecosystems. We investigated the effects of leaf and root litter of a deciduous shrub, Betula nana, on decomposition, by examining species-specific decomposition patterns, as well as effects of Betula litter on the decomposition of other species. We conducted a 2-yr decomposition experiment in moist acidic tundra in northern Alaska, where we decomposed three tundra species (Vaccinium vitis-idaea, Rhododendron palustre, and Eriophorum vaginatum) alone and in combination with Betula litter. Decomposition patterns for leaf and root litter were determined using three different measures of decomposition (mass loss, respiration, extracellular enzyme activity). We report faster decomposition of Betula leaf litter compared to other species, with support for species differences coming from all three measures of decomposition. Mixing effects were less consistent among the measures, with negative mixing effects shown only for mass loss. In contrast, there were few species differences or mixing effects for root decomposition. Overall, we attribute longer-term litter mass loss patterns to patterns created by early decomposition processes in the first winter. We note numerous differences for species patterns between leaf and root decomposition, indicating that conclusions from leaf litter experiments should not be extrapolated to below-ground decomposition. The high decomposition rates of Betula leaf litter aboveground, and relatively similar decomposition rates of multiple species below, suggest a potential for increases in turnover in the fast-decomposing carbon pool of leaves and fine roots as the dominance of deciduous shrubs in the Arctic increases, but this outcome may be tempered by

  18. Tree litter and forest understorey vegetation: a conceptual framework to understand the effects of tree litter on a perennial geophyte, Anemone nemorosa.

    PubMed

    Baltzinger, Marie; Archaux, Frédéric; Dumas, Yann

    2012-05-01

    Litter is a key factor in structuring plant populations, through positive or negative interactions. The litter layer forms a mechanical barrier that is often strongly selective against individuals lacking hypocotyle plasticity. Litter composition also interacts with plant growth by providing beneficial nutrients or, inversely, by allowing harmful allelopathic leaching. As conspicuous litter fall accumulation is often observed under deciduous forests, interactions between tree litter and understorey plant populations are worthy of study. In a 1-year ex-situ experiment, the effects of tree litter on the growth of Anemone nemorosa, a small perennial forest geophyte, were investigated. Three 'litter quantity' treatments were defined, representative of forest floor litter (199, 356·5 and 514 g m(-2)), which were crossed with five 'litter composition' treatments (Quercus petraea, Fagus sylvatica, Carpinus betulus, Q. petraea + F. sylvatica and Q. petraea + C. betulus), plus a no-litter control. Path analysis was then used to investigate the pathways linking litter characteristics and components of adult plant growth. As expected, the heavier the litter, the longer the petiole; rhizome growth, however, was not depreciated by the litter-induced petiole lengthening. Both rhizome mass increment and number of initiated buds marginally increased with the amount of litter. Rhizome mass increment was in fact determined primarily by leaf area and leaf life span, neither of which was unequivocally correlated with any litter characteristics. However, the presence of litter significantly increased leafing success: following a late frost event, control rhizomes growing in the absence of litter experienced higher leaf mortality before leaf unfolding. The study questions the role of litter as a physical or chemical barrier to ground vegetation; to better understand this role, there is a need for ex-situ, longer-term experiments coupled with in-situ observations in the forest.

  19. Tree litter and forest understorey vegetation: a conceptual framework to understand the effects of tree litter on a perennial geophyte, Anemone nemorosa

    PubMed Central

    Baltzinger, Marie; Archaux, Frédéric; Dumas, Yann

    2012-01-01

    Background and Aims Litter is a key factor in structuring plant populations, through positive or negative interactions. The litter layer forms a mechanical barrier that is often strongly selective against individuals lacking hypocotyle plasticity. Litter composition also interacts with plant growth by providing beneficial nutrients or, inversely, by allowing harmful allelopathic leaching. As conspicuous litter fall accumulation is often observed under deciduous forests, interactions between tree litter and understorey plant populations are worthy of study. Methods In a 1-year ex-situ experiment, the effects of tree litter on the growth of Anemone nemorosa, a small perennial forest geophyte, were investigated. Three ‘litter quantity’ treatments were defined, representative of forest floor litter (199, 356·5 and 514 g m−2), which were crossed with five ‘litter composition’ treatments (Quercus petraea, Fagus sylvatica, Carpinus betulus, Q. petraea + F. sylvatica and Q. petraea + C. betulus), plus a no-litter control. Path analysis was then used to investigate the pathways linking litter characteristics and components of adult plant growth. Key Results As expected, the heavier the litter, the longer the petiole; rhizome growth, however, was not depreciated by the litter-induced petiole lengthening. Both rhizome mass increment and number of initiated buds marginally increased with the amount of litter. Rhizome mass increment was in fact determined primarily by leaf area and leaf life span, neither of which was unequivocally correlated with any litter characteristics. However, the presence of litter significantly increased leafing success: following a late frost event, control rhizomes growing in the absence of litter experienced higher leaf mortality before leaf unfolding. Conclusions The study questions the role of litter as a physical or chemical barrier to ground vegetation; to better understand this role, there is a need for ex-situ, longer

  20. The fate of nitrogen mineralized from leaf litter — Initial evidence from 15N-labeled litter

    Treesearch

    Kathryn B. Piatek

    2011-01-01

    Decomposition of leaf litter includes microbial immobilization of nitrogen (N), followed by N mineralization. The fate of N mineralized from leaf litter is unknown. I hypothesized that N mineralized from leaf litter will be re-immobilized into other forms of organic matter, including downed wood. This mechanism may retain N in some forests. To test this hypothesis, oak...

  1. Litter decomposition in southern Appalachian black locust and pine-hardwood stands: litter quality and nitrogen dynamics

    Treesearch

    David L. White; Bruce L. Haines

    1988-01-01

    The chemical quality of litter, through its interaction with macroclimate and the litter biota, largely regulates the rate of organic matter (OM) and nitrogen (N) turnover in the forest floor (Cromack 1973; Fogel and Cromack 1977; Meentemeyer 1978; Aber and Melillo 1982; Melillo et al. 1982). Litter quality is thought to be related to the N require-ment and...

  2. The effect of alum addition on microbial communities in poultry litter.

    PubMed

    Rothrock, M J; Cook, K L; Warren, J G; Sistani, K

    2008-08-01

    and elucidating their role in the acidified litter environment.

  3. Long-term marine litter monitoring in the remote Great Australian Bight, South Australia.

    PubMed

    Edyvane, K S; Dalgetty, A; Hone, P W; Higham, J S; Wace, N M

    2004-06-01

    , fishing-related litter in the Bight has reduced at a slower rate than domestic litter. While the level of glass and soft plastics on the beach have both reduced by almost 93% (i.e. 103-7 kg and 119-8 kg, respectively), the level of hard plastics, has diminished at a slower rate, with reductions of only 75% (i.e. 122-30 kg). Some fisheries (i.e. rock lobster, Southern Shark Fishery) have shown marked reductions in fishing-related litter. This is probably due, to some extent, to significant reductions in fishing effort in the region, although this requires further investigation. The information from the Anxious Bay beach litter survey is crucial in monitoring trends in ocean litter in Australia's southern oceans and compliance with international litter regulations. While fishing-related litter remains the major source of ship-based or ocean litter in Australia's southern oceans, the continued reduction in ship-based litter since 1991 supports increasing compliance to MARPOL (Annex V) by commercial fisheries and shipping in the Great Australian Bight. While Australia participates in marine debris monitoring programs in the Antarctic (under CCAMLR), there is currently no national program or management framework to assess, manage and monitor ocean-based litter along Australia's coasts, and monitor compliance with MARPOL. Apart from the commitments under CCAMLR for Antarctic (and sub-Antarctic) marine environments, there are no other regional programs, guidelines or monitoring protocols or to assess and manage ocean litter in the Southern Ocean.

  4. Poultry litter environment selects for the development of antibiotic resistance (AR) in Salmonella Heidelberg via conjugative IncX plasmids

    USDA-ARS?s Scientific Manuscript database

    The fitness of S. Heidelberg in poultry litter (PL) was determined following growth preconditioning in either Brain Heart Infusion (BHI) broth or poultry litter extracts (PLE, a centrifuged and filter sterilized PL slurry). Isolates were monitored by direct culture count for up to 9 days. The concen...

  5. Marine litter on the seafloor of the Faial-Pico Passage, Azores Archipelago.

    PubMed

    Rodríguez, Yasmina; Pham, Christopher K

    2017-03-15

    Plastic pollution in the marine environment attracts much attention from both researchers and the general public. Plastic items and other debris are commonly observed everywhere in the ocean, from the surface down to the deep ocean floor. In this study, we analysed 45.2km of video footage, collected during 56 transects surveying the seafloor of the Faial-Pico Passage in order to quantify the abundance of marine litter and its interactions with benthic fauna. The footage was collected by a Remotely Operated Vehicle (ROV) and a manned submersible at depths ranging between 40 and 525m. The mean litter density in the passage was 0.26±0.03 items·100m -1 (±SE) and was significantly higher between 151 and 250m compared to other depth strata. Overall, derelict fishing gear, mostly made of plastic, were the most common objects found on the seafloor, representing 64% of all items. Although we observed few evidence of direct deleterious effects by the litter, interactions with fauna were observed in more than half of the items. This study makes an important contribution in quantifying the abundance of marine litter on the seafloor of the Azores. The location of the Faial-Pico Passage, close to shore, makes it an appropriate site for long-term monitoring of litter on the seafloor and evaluate the efficiency of upcoming public policies aimed at reducing litter input into the oceans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Environmentally-friendly animal litter

    DOEpatents

    Boxley, Chett; McKelvie, Jessica

    2012-08-28

    An animal litter composition including geopolymerized ash particulates having a network of repeating aluminum-silicon units is described herein. Generally, the animal litter is made from a quantity of a pozzolanic ash mixed with a sufficient quantity of water and an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. After the geopolymerized ash is formed, it is dried, broken into particulates, and sieved to a desired size. These geopolymerized ash particulates are used to make a non-clumping or clumping animal litter. Odor control is accomplished with the addition of a urease inhibitor, pH buffer, an odor eliminating agent, and/or fragrance.

  7. Environmentally-friendly animal litter

    DOEpatents

    Boxley, Chett; McKelvie, Jessica

    2013-09-03

    An animal litter composition that includes geopolymerized ash particulates having a network of repeating aluminum-silicon units is described herein. Generally, the animal litter is made from a quantity of a pozzolanic ash mixed with an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. This geopolymerization reaction may occur within a pelletizer. After the geopolymerized ash is formed, it may be dried and sieved to a desired size. These geopolymerized ash particulates may be used to make a non-clumping or clumping animal litter or other absorbing material. Aluminum sulfate, clinoptilolite, silica gel, sodium alginate and mineral oil may be added as additional ingredients.

  8. Factors affecting birth weight in sheep: maternal environment

    PubMed Central

    Gardner, D S; Buttery, P J; Daniel, Z; Symonds, M E

    2007-01-01

    Knowledge of factors affecting variation in birth weight is especially important given the relationship of birth weight to neonatal and adult health. The present study utilises two large contemporary datasets in sheep of differing breeds to explore factors that influence weight at term. For dataset one (Study 1; n = 154 Blue-faced Leicester×Swaledale (Mule) and 87 Welsh Mountain ewes, 315 separate cases of birth weight), lamb birth weight as the outcome measure was related to maternal characteristics and individual energy intake of the ewe during specified periods of gestation, i.e. early (1-30 days; term ∼147 days gestation), mid (31-80 days) or late (110-147 days) pregnancy. For dataset two (Study 2; n = 856 Mule ewes and 5821 cases of birth weight), we investigated using multilevel modelling the influence of ewe weight, parity, barrenness, lamb sex, litter size, lamb mortality and year of birth on lamb birth weight. For a subset of these ewes (n = 283), the effect of the ewes’ own birth weight was also examined. Interactions between combinations of variables were selectively investigated. Litter size, as expected, had the single greatest influence on birth weight with other significant effects being year of birth, maternal birth weight, maternal nutrition, sex of the lamb, ewe barrenness and maternal body composition at mating. The results of the present study have practical implications not only for sheep husbandry but also for the increased knowledge of factors that significantly influence variation in birth weight; as birth weight itself has become a significant predictor of later health outcomes. PMID:17244755

  9. Tree species diversity affects decomposition through modified micro-environmental conditions across European forests.

    PubMed

    Joly, François-Xavier; Milcu, Alexandru; Scherer-Lorenzen, Michael; Jean, Loreline-Katia; Bussotti, Filippo; Dawud, Seid Muhie; Müller, Sandra; Pollastrini, Martina; Raulund-Rasmussen, Karsten; Vesterdal, Lars; Hättenschwiler, Stephan

    2017-05-01

    Different tree species influence litter decomposition directly through species-specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear. We addressed this question by studying the decomposition of two common substrates, cellulose paper and wood sticks, in a total of 209 forest stands of varying tree species diversity across six major forest types at the scale of Europe. Tree species richness showed a weak but positive correlation with the decomposition of cellulose but not with that of wood. Surprisingly, macroclimate had only a minor effect on cellulose decomposition and no effect on wood decomposition despite the wide range in climatic conditions among sites from Mediterranean to boreal forests. Instead, forest canopy density and stand-specific litter traits affected the decomposition of both substrates, with a particularly clear negative effect of the proportion of evergreen tree litter. Our study suggests that species richness and composition of tree canopies modify decomposition indirectly through changes in microenvironmental conditions. These canopy-induced differences in the local decomposition environment control decomposition to a greater extent than continental-scale differences in macroclimatic conditions. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  10. Biochemical Control of Fungal Biomass and Enzyme Production During Native Hawaiian Litter Degradation

    NASA Astrophysics Data System (ADS)

    Amatangelo, K. L.; Cordova, T. P.; Vitousek, P. M.

    2007-12-01

    Microbial growth and enzyme production during decomposition is controlled by the availability of carbon substrates, essential elements, and the ratios of these (such as lignin:N). We manipulated carbon:nutrient stoichiometry during decomposition using a natural fertility gradient in Hawaii and litter of varying initial biochemistry. We collected freshly senesced litter of seven biochemically distinct species from three sites offering differing levels of N, P, cations, and 15N , but similar yearly rainfall and temperature patterns. Litter types were decomposed at both the sites they were collected, and at the other site(s) that species was found. Litter was collected at multiple time points, and after one year of decomposition, calculated K constants varied an order of magnitude, from 0.276 to 2.76. Decomposition rates varied significantly with both litter site of origin and deployment, except at the oldest, P-limited site, where litter site of origin was not significantly correlated with decomposition within species. As microbial exocellular enzymes provide the catalyst for the breakdown of organic molecules including phenols, cellulose, and cutin, we assayed polyphenol oxidase, cellobiohydrolase, cutinase, chitinase, and lignin peroxidase to evaluate the breakdown sequence of different litter types. To measure the fungal biomass accumulating during decomposition, we extracted (22E)-Ergosta-5,7,22-trien-3beta- ol (ergosterol) on a subset of samples. The production of particular exocellular enzymes on litter species responded distinctly to origin and decomposition sites: after six months, chitinase and cellobiohydrolase were significantly affected by origin site, whereas polyphenol oxidase activity was controlled by deployment site. We conclude that site characteristics can alter the interaction between litter carbon:nutrient ratios and decomposition rate, mediated through microbial biomass and enzyme production.

  11. Litter of the hemiparasite Bartsia alpina enhances plant growth: evidence for a functional role in nutrient cycling.

    PubMed

    Quested, Helen M; Press, Malcolm C; Callaghan, Terry V

    2003-05-01

    Hemiparasitic angiosperms concentrate nutrients in their leaves and also produce high quality litter, which can decompose faster and release more nutrients than that of surrounding species. The impact of these litters on plant growth may be particularly important in nutrient-poor communities where hemiparisites can be abundant, such as the sub-Arctic. We tested the hypothesis that plant growth is enhanced by the litter of the hemiparasite Bartsia alpina, in comparison with litter of co-occurring dwarf shrub species, using a pot based bioassay approach. Growth of Betula nana and Poa alpina was up to 51% and 41% greater, respectively, in the presence of Bartsia alpina litter than when grown with dwarf shrub litter (Vaccinium uliginosum, Betula nana and Empetrum nigrum subsp. hermaphroditum). The nutrient concentrations of Betula nana plants grown with Bartsia alpina litter were almost double those of plants grown with dwarf shrub litter, and a significantly greater proportion of biomass was allocated to shoots rather than roots, strongly suggesting that nutrient availability was higher where Bartsia alpina litter was present. The presence of litter from dwarf shrubs, or the moss Hylocomium splendens, did not reduce the positive effect of Bartsia alpina litter on plant growth. E. nigrum litter did not appear to affect plant growth substantially differently from litter of other dwarf shrub species, despite earlier reports of its allelopathic action. The enhanced nutrient uptake and growth of plants in the presence of Bartsia alpina (and potentially other hemiparasitic species) litter could have important implications for communities in which it occurs, including enhanced survival of seedlings of co-occurring species and increased resource patchiness.

  12. Effects of Chicken Litter Storage Time and Ammonia Content on Thermal Resistance of Desiccation-Adapted Salmonella spp.

    PubMed

    Chen, Zhao; Wang, Hongye; Ionita, Claudia; Luo, Feng; Jiang, Xiuping

    2015-10-01

    Broiler chicken litter was kept as a stacked heap on a poultry farm, and samples were collected up to 9 months of storage. Chicken litter inoculated with desiccation-adapted Salmonella cells was heat-treated at 75, 80, 85, and 150°C. Salmonella populations decreased in all these samples during heat treatment, and the inactivation rates became lower in chicken litter when storage time was extended from 0 to 6 months. There was no significant difference (P > 0.05) in thermal resistance of Salmonella in 6- and 9-month litter samples, indicating that a threshold for thermal resistance was reached after 6 months. Overall, the thermal resistance of Salmonella in chicken litter was affected by the storage time of the litter. The changes in some chemical, physical, and microbiological properties during storage could possibly contribute to this difference. Moisture and ammonia could be two of the most significant factors influencing the thermal resistance of Salmonella cells in chicken litter. Our results emphasize the importance of adjusting time and temperature conditions for heat processing chicken litter when it is removed from the chicken house at different time intervals. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. Effects of Chicken Litter Storage Time and Ammonia Content on Thermal Resistance of Desiccation-Adapted Salmonella spp.

    PubMed Central

    Chen, Zhao; Wang, Hongye; Ionita, Claudia; Luo, Feng

    2015-01-01

    Broiler chicken litter was kept as a stacked heap on a poultry farm, and samples were collected up to 9 months of storage. Chicken litter inoculated with desiccation-adapted Salmonella cells was heat-treated at 75, 80, 85, and 150°C. Salmonella populations decreased in all these samples during heat treatment, and the inactivation rates became lower in chicken litter when storage time was extended from 0 to 6 months. There was no significant difference (P > 0.05) in thermal resistance of Salmonella in 6- and 9-month litter samples, indicating that a threshold for thermal resistance was reached after 6 months. Overall, the thermal resistance of Salmonella in chicken litter was affected by the storage time of the litter. The changes in some chemical, physical, and microbiological properties during storage could possibly contribute to this difference. Moisture and ammonia could be two of the most significant factors influencing the thermal resistance of Salmonella cells in chicken litter. Our results emphasize the importance of adjusting time and temperature conditions for heat processing chicken litter when it is removed from the chicken house at different time intervals. PMID:26209673

  14. Season mediates herbivore effects on litter and soil microbial abundance and activity in a semi-arid woodland

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Classen, Aimee T; Overby, Stephen; Hart, Stephen C

    2007-01-01

    Herbivores can directly impact ecosystem function by altering litter quality entering an ecosystem or indirectly by affecting a shift in the microbial community that mediate nutrient processes. We examine herbivore susceptibility and resistance effects on litter microarthropod and soil microbial communities to test the general hypothesis that herbivore driven changes in litter inputs will feedback to the microbial community. Our study population consisted of individual trees that are susceptible or resistant to the stem-boring moth (Dioryctria albovittella) and trees that herbivores have been manually removed since 1982. Moth herbivory increased pi on litter nitrogen concentrations (16%) and canopy precipitation infiltrationmore » (28%), both significant factors influencing litter and soil microbial populations. Our research resulted in three major conclusions: 1) In spite of an increase in litter quality, herbivory does not change litter microarthropod abundance or species richness. 2) Herbivore susceptibility alters bulk soil microbial communities, but not soil properties. 3) Season has a strong influence on microbial communities, and their response to herbivore inputs, in this semi-arid ecosystem.« less

  15. Quicklime treatment and stirring of different poultry litter substrates for reducing pathogenic bacteria counts.

    PubMed

    Lopes, M; Roll, V F B; Leite, F L; Dai Prá, M A; Xavier, E G; Heres, T; Valente, B S

    2013-03-01

    Testing different management practices can help to identify conditions that decrease or even eliminate pathogenic bacteria in poultry litter. A trial was conducted to evaluate the effects of daily manual stirring (rotation of the litter with a pitchfork) for the first 14 d of a bird's life (WDR), in 3 types of poultry litter substrates and quicklime treatment (CaO) during layout time between flocks on pathogenic bacteria occurrence (cfu). A total of 216 male Cobb broilers were randomly allotted to 18 pens with new litter (experimental unit). A split-plot design, with 6 treatments allotted to the main plots, was used: 1) wood shavings (WS) + WDR, 2) WS without stirring up to 14 d (WODR), 3) rice hulls (RIH) + WDR, 4) RIH + WODR, 5) mixture of 50% RIH and WS + WDR, and 6) mixture of 50% RIH and WS + WODR. Two treatments were allotted to the subplots: 0 and 300 g of CaO•m(-2) litter. After depopulation, litter samples were collected, and CaO was incorporated into the litter in the designated half of each pen. The cfu from litter samples after 7 d of the quicklime treatment were counted on Chapman agar, brain heart infusion media, and MacConkey agar. The data were analyzed using ANOVA, and the means were compared by least squares means (P < 0.05). Neither the type of substrate nor the act of stirring affected the cfu. The incorporation of 300 g of CaO•m(-2) litter efficiently reduced the cfu observed on brain heart infusion, Chapman agar, and MacConkey agar media by 57.2, 66.9, and 92.1%, respectively, compared with control (6.4, 17.9, and 46.1%; P < 0.001). In conclusion, the incorporation of 300 g/m(-2) of quicklime in poultry litter reduces the cfu, regardless of the substrate and stirring performed.

  16. Who is who in litter decomposition? Metaproteomics reveals major microbial players and their biogeochemical functions

    PubMed Central

    Schneider, Thomas; Keiblinger, Katharina M; Schmid, Emanuel; Sterflinger-Gleixner, Katja; Ellersdorfer, Günther; Roschitzki, Bernd; Richter, Andreas; Eberl, Leo; Zechmeister-Boltenstern, Sophie; Riedel, Kathrin

    2012-01-01

    Leaf-litter decomposition is a central process in carbon cycling; however, our knowledge about the microbial regulation of this process is still scarce. Metaproteomics allows us to link the abundance and activity of enzymes during nutrient cycling to their phylogenetic origin based on proteins, the ‘active building blocks' in the system. Moreover, we employed metaproteomics to investigate the influence of environmental factors and nutrients on the decomposer structure and function during beech litter decomposition. Litter was collected at forest sites in Austria with different litter nutrient content. Proteins were analyzed by 1-D-SDS-PAGE followed by liquid-chromatography and tandem mass-spectrometry. Mass spectra were assigned to phylogenetic and functional groups by a newly developed bioinformatics workflow, assignments being validated by complementary approaches. We provide evidence that the litter nutrient content and the stoichiometry of C:N:P affect the decomposer community structure and activity. Fungi were found to be the main producers of extracellular hydrolytic enzymes, with no bacterial hydrolases being detected by our metaproteomics approach. Detailed investigation of microbial succession suggests that it is influenced by litter nutrient content. Microbial activity was stimulated at higher litter nutrient contents via a higher abundance and activity of extracellular enzymes. PMID:22402400

  17. Enhanced summer warming reduces fungal decomposer diversity and litter mass loss more strongly in dry than in wet tundra.

    PubMed

    Christiansen, Casper T; Haugwitz, Merian S; Priemé, Anders; Nielsen, Cecilie S; Elberling, Bo; Michelsen, Anders; Grogan, Paul; Blok, Daan

    2017-01-01

    Many Arctic regions are currently experiencing substantial summer and winter climate changes. Litter decomposition is a fundamental component of ecosystem carbon and nutrient cycles, with fungi being among the primary decomposers. To assess the impacts of seasonal climatic changes on litter fungal communities and their functioning, Betula glandulosa leaf litter was surface-incubated in two adjacent low Arctic sites with contrasting soil moisture regimes: dry shrub heath and wet sedge tundra at Disko Island, Greenland. At both sites, we investigated the impacts of factorial combinations of enhanced summer warming (using open-top chambers; OTCs) and deepened snow (using snow fences) on surface litter mass loss, chemistry and fungal decomposer communities after approximately 1 year. Enhanced summer warming significantly restricted litter mass loss by 32% in the dry and 17% in the wet site. Litter moisture content was significantly reduced by summer warming in the dry, but not in the wet site. Likewise, fungal total abundance and diversity were reduced by OTC warming at the dry site, while comparatively modest warming effects were observed in the wet site. These results suggest that increased evapotranspiration in the OTC plots lowered litter moisture content to the point where fungal decomposition activities became inhibited. In contrast, snow addition enhanced fungal abundance in both sites but did not significantly affect litter mass loss rates. Across sites, control plots only shared 15% of their fungal phylotypes, suggesting strong local controls on fungal decomposer community composition. Nevertheless, fungal community functioning (litter decomposition) was negatively affected by warming in both sites. We conclude that although buried soil organic matter decomposition is widely expected to increase with future summer warming, surface litter decay and nutrient turnover rates in both xeric and relatively moist tundra are likely to be significantly restricted by

  18. Leaf litter breakdown of native and exotic tree species in two Hawaiian streams that differ in flow

    Treesearch

    Megan Roberts; Ayron M. Strauch; Tracy Wiegner; Richard A. Mackenzie

    2016-01-01

    Riparian leaf litter is a major source of allochthonous organic material to temperate and tropical streams, promoting primary and secondary productivity in lotic and nearshore habitats. In tropical island streams, where native leaf-shredding macroinvertebrates are absent, physical fragmentation from stream flow is an important factor affecting leaf litter breakdown and...

  19. The Experimental Control of Littering

    ERIC Educational Resources Information Center

    Clark, Roger N.; And Others

    1972-01-01

    Behavior, incentives, and education programs were researched as factors relating to littering. Experiments in theaters, forest campgrounds, and hiking and dispersed car camping areas indicate incentive systems are necessary and feasible for curbing litter problems. (BL)

  20. Influence of Litter Diversity on Dissolved Organic Matter Release and Soil Carbon Formation in a Mixed Beech Forest

    PubMed Central

    Scheibe, Andrea; Gleixner, Gerd

    2014-01-01

    We investigated the effect of leaf litter on below ground carbon export and soil carbon formation in order to understand how litter diversity affects carbon cycling in forest ecosystems. 13C labeled and unlabeled leaf litter of beech (Fagus sylvatica) and ash (Fraxinus excelsior), characterized by low and high decomposability, were used in a litter exchange experiment in the Hainich National Park (Thuringia, Germany). Litter was added in pure and mixed treatments with either beech or ash labeled with 13C. We collected soil water in 5 cm mineral soil depth below each treatment biweekly and determined dissolved organic carbon (DOC), δ13C values and anion contents. In addition, we measured carbon concentrations and δ13C values in the organic and mineral soil (collected in 1 cm increments) up to 5 cm soil depth at the end of the experiment. Litter-derived C contributes less than 1% to dissolved organic matter (DOM) collected in 5 cm mineral soil depth. Better decomposable ash litter released significantly more (0.50±0.17%) litter carbon than beech litter (0.17±0.07%). All soil layers held in total around 30% of litter-derived carbon, indicating the large retention potential of litter-derived C in the top soil. Interestingly, in mixed (ash and beech litter) treatments we did not find a higher contribution of better decomposable ash-derived carbon in DOM, O horizon or mineral soil. This suggest that the known selective decomposition of better decomposable litter by soil fauna has no or only minor effects on the release and formation of litter-derived DOM and soil organic matter. Overall our experiment showed that 1) litter-derived carbon is of low importance for dissolved organic carbon release and 2) litter of higher decomposability is faster decomposed, but litter diversity does not influence the carbon flow. PMID:25486628

  1. Influence of litter diversity on dissolved organic matter release and soil carbon formation in a mixed beech forest.

    PubMed

    Scheibe, Andrea; Gleixner, Gerd

    2014-01-01

    We investigated the effect of leaf litter on below ground carbon export and soil carbon formation in order to understand how litter diversity affects carbon cycling in forest ecosystems. 13C labeled and unlabeled leaf litter of beech (Fagus sylvatica) and ash (Fraxinus excelsior), characterized by low and high decomposability, were used in a litter exchange experiment in the Hainich National Park (Thuringia, Germany). Litter was added in pure and mixed treatments with either beech or ash labeled with 13C. We collected soil water in 5 cm mineral soil depth below each treatment biweekly and determined dissolved organic carbon (DOC), δ13C values and anion contents. In addition, we measured carbon concentrations and δ13C values in the organic and mineral soil (collected in 1 cm increments) up to 5 cm soil depth at the end of the experiment. Litter-derived C contributes less than 1% to dissolved organic matter (DOM) collected in 5 cm mineral soil depth. Better decomposable ash litter released significantly more (0.50±0.17%) litter carbon than beech litter (0.17±0.07%). All soil layers held in total around 30% of litter-derived carbon, indicating the large retention potential of litter-derived C in the top soil. Interestingly, in mixed (ash and beech litter) treatments we did not find a higher contribution of better decomposable ash-derived carbon in DOM, O horizon or mineral soil. This suggest that the known selective decomposition of better decomposable litter by soil fauna has no or only minor effects on the release and formation of litter-derived DOM and soil organic matter. Overall our experiment showed that 1) litter-derived carbon is of low importance for dissolved organic carbon release and 2) litter of higher decomposability is faster decomposed, but litter diversity does not influence the carbon flow.

  2. Controls on mass loss and nitrogen dynamics of oak leaf litter along an urban-rural land-use gradient

    Treesearch

    Richard V. Pouyat; Margaret M. Carreiro

    2003-01-01

    Using reciprocal leaf litter transplants, we investigated the effects of contrasting environments (urban vs. rural) and intraspecific variations in oak leaf litter quality on mass loss rates and nitrogen (N) dynamics along an urban-rural gradient in the New York City metropolitan area. Differences in earthworm abundances and temperature had previously been documented...

  3. Trees as templates for tropical litter arthropod diversity.

    PubMed

    Donoso, David A; Johnston, Mary K; Kaspari, Michael

    2010-09-01

    Increased tree species diversity in the tropics is associated with even greater herbivore diversity, but few tests of tree effects on litter arthropod diversity exist. We studied whether tree species influence patchiness in diversity and abundance of three common soil arthropod taxa (ants, gamasid mites, and oribatid mites) in a Panama forest. The tree specialization hypothesis proposes that tree-driven habitat heterogeneity maintains litter arthropod diversity. We tested whether tree species differed in resource quality and quantity of their leaf litter and whether more heterogeneous litter supports more arthropod species. Alternatively, the abundance-extinction hypothesis states that arthropod diversity increases with arthropod abundance, which in turn tracks resource quantity (e.g., litter depth). We found little support for the hypothesis that tropical trees are templates for litter arthropod diversity. Ten tree species differed in litter depth, chemistry, and structural variability. However, the extent of specialization of invertebrates on particular tree taxa was low and the more heterogeneous litter between trees failed to support higher arthropod diversity. Furthermore, arthropod diversity did not track abundance or litter depth. The lack of association between tree species and litter arthropods suggests that factors other than tree species diversity may better explain the high arthropod diversity in tropical forests.

  4. Is it worth hyperaccumulating Ni on non-serpentine soils? Decomposition dynamics of mixed-species litters containing hyperaccumulated Ni across serpentine and non-serpentine environments.

    PubMed

    Adamidis, George C; Kazakou, Elena; Aloupi, Maria; Dimitrakopoulos, Panayiotis G

    2016-06-01

    Nickel (Ni)-hyperaccumulating species produce high-Ni litters and may potentially influence important ecosystem processes such as decomposition. Although litters resembling the natural community conditions are essential in order to predict decomposition dynamics, decomposition of mixed-species litters containing hyperaccumulated Ni has never been studied. This study aims to test the effect of different litter mixtures containing hyperaccumulated Ni on decomposition and Ni release across serpentine and non-serpentine soils. Three different litter mixtures were prepared based on the relative abundance of the dominant species in three serpentine soils in the island of Lesbos, Greece where the Ni-hyperaccumulator Alyssum lesbiacum is present. Each litter mixture decomposed on its original serpentine habitat and on an adjacent non-serpentine habitat, in order to investigate whether the decomposition rates differ across the contrasted soils. In order to make comparisons across litter mixtures and to investigate whether additive or non-additive patterns of mass loss occur, a control non-serpentine site was used. Mass loss and Ni release were measured after 90, 180 and 270 d of field exposure. The decomposition rates and Ni release had higher values on serpentine soils after all periods of field exposure. The recorded rapid release of hyperaccumulated Ni is positively related to the initial litter Ni concentration. No differences were found in the decomposition of the three different litter mixtures at the control non-serpentine site, while their patterns of mass loss were additive. Our results: (1) demonstrate the rapid decomposition of litters containing hyperaccumulated Ni on serpentine soils, indicating the presence of metal-tolerant decomposers; and (2) imply the selective decomposition of low-Ni parts of litters by the decomposers on non-serpentine soils. This study provides support for the elemental allelopathy hypothesis of hyperaccumulation, presenting the

  5. Study on Hydrological Functions of Litter Layers in North China

    PubMed Central

    Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

    2013-01-01

    Canopy interception, throughfall, stemflow, and runoff have received considerable attention during the study of water balance and hydrological processes in forested ecosystems. Past research has either neglected or underestimated the role of hydrological functions of litter layers, although some studies have considered the impact of various characteristics of rainfall and litter on litter interception. Based on both simulated rainfall and litter conditions in North China, the effect of litter mass, rainfall intensity and litter type on the maximum water storage capacity of litter (S) and litter interception storage capacity (C) were investigated under five simulated rainfall intensities and four litter masses for two litter types. The results indicated: 1) the S values increased linearly with litter mass, and the S values of broadleaf litter were on average 2.65 times larger than the S values of needle leaf litter; 2) rainfall intensity rather than litter mass determined the maximum interception storage capacity (Cmax); Cmax increased linearly with increasing rainfall intensity; by contrast, the minimum interception storage capacity (Cmin) showed a linear relationship with litter mass, but a poor correlation with rainfall intensity; 3) litter type impacted Cmax and Cmin; the values of Cmax and Cmin for broadleaf litter were larger than those of needle leaf litter, which indicated that broadleaf litter could intercepte and store more water than needle leaf litter; 4) a gap existed between Cmax and Cmin, indicating that litter played a significant role by allowing rainwater to infiltrate or to produce runoff rather than intercepting it and allowing it to evaporate after the rainfall event; 5) Cmin was always less than S at the same litter mass, which should be considered in future interception predictions. Vegetation and precipitation characteristics played important roles in hydrological characteristics. PMID:23936188

  6. Sequential monitoring of beach litter using webcams.

    PubMed

    Kako, Shin'ichiro; Isobe, Atsuhiko; Magome, Shinya

    2010-05-01

    This study attempts to establish a system for the sequential monitoring of beach litter using webcams placed at the Ookushi beach, Goto Islands, Japan, to establish the temporal variability in the quantities of beach litter every 90 min over a one and a half year period. The time series of the quantities of beach litter, computed by counting pixels with a greater lightness than a threshold value in photographs, shows that litter does not increase monotonically on the beach, but fluctuates mainly on a monthly time scale or less. To investigate what factors influence this variability, the time derivative of the quantity of beach litter is compared with satellite-derived wind speeds. It is found that the beach litter quantities vary largely with winds, but there may be other influencing factors. (c) 2010 Elsevier Ltd. All rights reserved.

  7. Temperatures below leaf litter during winter prescribed burns: implications for litter-roosting bats

    Treesearch

    Roger W. Perry; Virginia L. McDaniel

    2015-01-01

    Some bat species, including eastern red bats (Lasiurus borealis), roost for short periods beneath leaf litter on the forest floor during winter in the south-eastern USA, a region subjected to frequent fire. The variability in fuel consumption, the heterogeneous nature of burns, and the effects of litter and duff moisture on forest-floor...

  8. Changes in litter near an aluminum reduction plant

    USGS Publications Warehouse

    Beyer, W.N.; Fleming, W.J.; Swineford, D.

    1987-01-01

    Litter was collected from eight sites at distances as far as 33 km from an AI reduction plant in western Tennessee. As a result of an accumulation of fine litter (< 4.75 mm) the weight of the litter per unit area was abnormally high at the two sites within 2 km of the plant. Compared to litter collected far from the plant, it had a lower fiber content, was more sapric, and was less acid. Fluoride emissions from the plant were suggested as the probable cause of litter changes. Concentrations of water-extractable and acid-extractable F- in the litter, the 0- to 5-cm soil layer, and the 5- to 15-cm soil layer were strongly correlated with distance from the plant. Total acid-extractable F- in the litter and upper 15 cm of soil was about 41 times as much at the closest site (700 mg/kg) as at the most distant sites (12 and 16 mg/kg). In a bioassay of litter from our study sites, woodlice (Porcellio scaber Latr.) had an abnormally high mortality in litter that contained 440 mg/kg or more of acid-extractable F-. However, when F- was added as NaF to litter, a significant increase in mortality was observed only in treatments exceeding 800 mg/kg. The decrease in the rate of decomposition of the litter might eventually induce a deficiency of soil macronutrients, but none was detected.

  9. Growth and mycorrhizal community structure of Pinus sylvestris seedlings following the addition of forest litter.

    PubMed

    Aucina, Algis; Rudawska, Maria; Leski, Tomasz; Skridaila, Audrius; Riepsas, Edvardas; Iwanski, Michal

    2007-08-01

    We report the effects of pine and oak litter on species composition and diversity of mycorrhizal fungi colonizing 2-year-old Pinus sylvestris L. seedlings grown in a bare-root nursery in Lithuania. A layer of pine or oak litter was placed on the surface of the nursery bed soil to mimic natural litter cover. Oak litter amendment appeared to be most favorable for seedling survival, with a 73% survival rate, in contrast to the untreated mineral bed soil (44%). The concentrations of total N, P, K, Ca, and Mg were higher in oak growth medium than in pine growth medium. Relative to the control (pH 6.1), the pH was lower in pine growth medium (5.8) and higher in oak growth medium (6.3). There were also twofold and threefold increases in the C content of growth medium with the addition of pine and oak litter, respectively. Among seven mycorrhizal morphotypes, eight different mycorrhizal taxa were identified: Suillus luteus, Suillus variegatus, Wilcoxina mikolae, a Tuber sp., a Tomentella sp., Cenococcum geophilum, Amphinema byssoides, and one unidentified ectomycorrhizal symbiont. Forest litter addition affected the relative abundance of mycorrhizal symbionts more than their overall representation. This was more pronounced for pine litter than for oak litter, with 40% and 25% increases in the abundance of suilloid mycorrhizae, respectively. Our findings provide preliminary evidence that changes in the supply of organic matter through litter manipulation may have far-reaching effects on the chemistry of soil, thus influencing the growth and survival of Scots pine seedlings and their mycorrhizal communities.

  10. Reflectance of litter accumulation levels at five wavelengths within the 0.5- to 2.5 micron waveband

    NASA Technical Reports Server (NTRS)

    Gerbermann, A. H.; Everitt, J. H.; Gausman, H. W. (Principal Investigator)

    1982-01-01

    Reflectance was measured for 1-m2 range grass plots with two canopy treatments (standing and clipped) and four levels of litter accumulation and for grain sorghum with two canopy treatments. Reflectance was significantly higher at the 0.65- to 1.65-, and 2.20-micrometer. Wavelengths for both grass and grain sorghum canopies when the canopies were clipped and the resulting litter was removed. The natural accumulation of litter under the grass canopy did not significantly affect reflectance. The 1.65- and 2.20-micrometer wavelength reflectances of the live grass and the intact litter were 21.8% and 16.2%, respectively, and those of grain sorghum were 21.8% and 16.5%, respectively.

  11. Effects of elevated atmospheric CO2 on competition between the mosquitoes Aedes albopictus and Ae. triseriatus via changes in litter quality and production.

    PubMed

    Smith, C; Baldwin, A H; Sullivan, J; Leisnham, P T

    2013-05-01

    Elevated atmospheric CO2 can alter aquatic communities via changes in allochthonous litter inputs. We tested effects of atmospheric CO2 on the invasive Aedes albopictus (Skuse) and native Aedes triseriatus (Say) (Diptera: Culicidae) via changes in competition for microbial food or resource inhibition/toxicity. Quercus alba L. litter was produced under elevated (879 ppm) and ambient (388 ppm) atmospheric CO2. Saplings grown at elevated CO2 produced greater litter biomass, which decayed faster and leached more tannins than saplings at ambient CO2. Competition was tested by raising larvae in different species and density combinations provisioned with elevated- or ambient-CO2 litter. Species-specific performance to water conditions was tested by providing single-species larval cohorts with increasing amounts of elevated- or ambient-CO2 litter, or increasing concentrations of tannic acid. Larval densities affected some fitness parameters of Ae. albopictus and Ae. triseriatus, but elevated-CO2 litter did not modify the effects of competition on population growth rates or any fitness parameters. Population growth rates and survival of each species generally were affected negatively by increasing amounts of both elevated- and ambient-CO2 litter from 0.252 to 2.016 g/liter, and tannic acid concentrations above 100 mg/liter were entirely lethal to both species. Aedes albopictus had consistently higher population growth rates than Ae. triseriatus. These results suggest that changes to litter production and chemistry from elevated CO2 are unlikely to affect the competitive outcome between Ae. albopictus and Ae. triseriatus, but that moderate increases in litter production increase population growth rates of both species until a threshold is exceeded that results in resource inhibition and toxicity.

  12. Genotype × Herbivore Effect on Leaf Litter Decomposition in Betula Pendula Saplings: Ecological and Evolutionary Consequences and the Role of Secondary Metabolites

    PubMed Central

    Silfver, Tarja; Paaso, Ulla; Rasehorn, Mira; Rousi, Matti; Mikola, Juha

    2015-01-01

    Plant genetic variation and herbivores can both influence ecosystem functioning by affecting the quantity and quality of leaf litter. Few studies have, however, investigated the effects of herbivore load on litter decomposition at plant genotype level. We reduced insect herbivory using an insecticide on one half of field-grown Betula Pendula saplings of 17 genotypes, representing random intrapopulation genetic variation, and allowed insects to naturally colonize the other half. We hypothesized that due to induced herbivore defence, saplings under natural herbivory produce litter of higher concentrations of secondary metabolites (terpenes and soluble phenolics) and have slower litter decomposition rate than saplings under reduced herbivory. We found that leaf damage was 89 and 53% lower in the insecticide treated saplings in the summer and autumn surveys, respectively, which led to 73% higher litter production. Litter decomposition rate was also affected by herbivore load, but the effect varied from positive to negative among genotypes and added up to an insignificant net effect at the population level. In contrast to our hypothesis, concentrations of terpenes and soluble phenolics were higher under reduced than natural herbivory. Those genotypes, whose leaves were most injured by herbivores, produced litter of lowest mass loss, but unlike we expected, the concentrations of terpenes and soluble phenolics were not linked to either leaf damage or litter decomposition. Our results show that (1) the genetic and herbivore effects on B. pendula litter decomposition are not mediated through variation in terpene or soluble phenolic concentrations and suggest that (2) the presumably higher insect herbivore pressure in the future warmer climate will not, at the ecological time scale, affect the mean decomposition rate in genetically diverse B. pendula populations. However, (3) due to the significant genetic variation in the response of decomposition to herbivory, evolutionary

  13. Type of litter determines the formation and properties of charred material during wildfires

    NASA Astrophysics Data System (ADS)

    Chavez, Bruno; Fonturbel, M. Teresa; Salgado, Josefa; García-Oliva, Felipe; Vega, Jose A.; Merino, Agustin

    2014-05-01

    Wildfire is one of the most important disturbances all over the World, affecting both the amount and composition of forest floor and mineral soils. In comparison with unburnt areas, wildfire-affected forest floor usually shows lower contents of labile C compounds and higher concentrations of recalcitrant aromatic forms. These changes in composition can have important impact on biogeochemical cycles and therefore ecosystem functions. Although burning of different types of litter can lead to different amount and types of pyrogenic compounds, this aspect has not been evaluated yet. The effect of wildfire on SOM composition and stability were evaluated in five major types of non-wood litter in Mediterranean ecosystems: Pinus nigra, E. arborea, P. pinaster, U. europaeus and Eucalyptus globulus. In each of these ecosystems, forest floor samples from different soil burn severities were sampled. Soil burnt severities were based on visual signs of changes in forest floor and deposition of ash. Pyrogenic carbon quality were analysed using elementary analysis, solid-state 13 C nuclear magnetic resonance spectroscopy, Reflectance Infrared Fourier Transform (FTIR) and thermal analysis (simultaneous DSC-TG). The study showed that the different types of litter influenced the formation and characteristics of charred material. They differed in the temperature at which they start to be formed, the amounts of charred compounds and in their chemical composition. The resulting charred materials from the different litter, showed an important variability in the degree of carbonitation/aromatization. Unlike the biochar obtained through pyrolysis of woody sources, which contains exclusively aromatic structures, in the charred material produced in some litter, lignin, cellulose and even cellulose persist even in the high soil burnt severity. Coinciding with increases in aromatic contents, important decreases in atomic H/C and O/C ratios were recorded. However, the values found in some

  14. Soil microbial communities and enzyme activities under various poultry litter application rates.

    PubMed

    Acosta-Martínez, V; Harmel, R Daren

    2006-01-01

    The potential excessive nutrient and/or microbial loading from mismanaged land application of organic fertilizers is forcing changes in animal waste management. Currently, it is not clear to what extent different rates of poultry litter impact soil microbial communities, which control nutrient availability, organic matter quality and quantity, and soil degradation potential. From 2002 to 2004, we investigated the microbial community and several enzyme activities in a Vertisol soil (fine, smectitic, thermic, Udic Haplustert) at 0 to 15 cm as affected by different rates of poultry litter application to pasture (0, 6.7, and 13.4 Mg ha(-1)) and cultivated sites (0, 4.5, 6.7, 9.0, 11.2, and 13.4 Mg ha(-1)) in Texas, USA. No differences in soil pH (average: 7.9), total N (pasture: 2.01-3.53, cultivated: 1.09-1.98 g kg(-1) soil) or organic C (pasture average: 25-26.7, cultivated average: 13.9-16.1 g kg(-1) soil) were observed following the first four years of litter application. Microbial biomass carbon (MBC) and nitrogen (MBN) increased at litter rates greater than 6.7 Mg ha(-1) (pasture: MBC = >863, MBN = >88 mg kg(-1) soil) compared to sites with no applied litter (MBC = 722, MBN = 69 mg kg(-1) soil). Enzyme activities of C (beta-glucosidase, alpha-galactosidase, beta-glucosaminidase) or N cycling (beta-glucosaminidase) were increased at litter rates greater than 6.7 Mg ha(-1). Enzyme activities of P (alkaline phosphatase) and S (arylsulfatase) mineralization showed the same response in pasture, but they were only increased at the highest (9.0, 11.2, and 13.4 Mg ha(-1)) litter application rates in cultivated sites. According to fatty acid methyl ester (FAME) analysis, the pasture soils experienced shifts to higher bacterial populations at litter rates of 6.7 Mg ha(-1), and shifts to higher fungal populations at the highest litter application rates in cultivated sites. While rates greater than 6.7 Mg ha(-1) provided rapid enhancement of the soil microbial populations

  15. Litter survey : status report 1.

    DOT National Transportation Integrated Search

    1979-01-01

    At the request of the Division of Litter Control of the Department of Conservation and Economic Development, the Research Council has initiated a litter survey program at approximately 25 sites on the state highway system. The purpose of this program...

  16. Litter mixture dominated by leaf litter of the invasive species, Flaveria bidentis, accelerates decomposition and favors nitrogen release.

    PubMed

    Li, Huiyan; Wei, Zishang; Huangfu, Chaohe; Chen, Xinwei; Yang, Dianlin

    2017-01-01

    In natural ecosystems, invasive plant litter is often mixed with that of native species, yet few studies have examined the decomposition dynamics of such mixtures, especially across different degrees of invasion. We conducted a 1-year litterbag experiment using leaf litters from the invasive species Flaveria bidentis (L.) and the dominant co-occurring native species, Setaria viridis (L.). Litters were allowed to decompose either separately or together at different ratios in a mothproof screen house. The mass loss of all litter mixtures was non-additive, and the direction and strength of effects varied with species ratio and decomposition stage. During the initial stages of decomposition, all mixtures had a neutral effect on the mass loss; however, at later stages of decomposition, mixtures containing more invasive litter had synergistic effects on mass loss. Importantly, an increase in F. bidentis litter with a lower C:N ratio in mixtures led to greater net release of N over time. These results highlight the importance of trait dissimilarity in determining the decomposition rates of litter mixtures and suggest that F. bidentis could further synchronize N release from litter as an invasion proceeds, potentially creating a positive feedback linked through invasion as the invader outcompetes the natives for nutrients. Our findings also demonstrate the importance of species composition as well as the identity of dominant species when considering how changes in plant community structure influence plant invasion.

  17. Inhibitory and toxic effects of extracellular self-DNA in litter: a mechanism for negative plant-soil feedbacks?

    PubMed

    Mazzoleni, Stefano; Bonanomi, Giuliano; Incerti, Guido; Chiusano, Maria Luisa; Termolino, Pasquale; Mingo, Antonio; Senatore, Mauro; Giannino, Francesco; Cartenì, Fabrizio; Rietkerk, Max; Lanzotti, Virginia

    2015-02-01

    Plant-soil negative feedback (NF) is recognized as an important factor affecting plant communities. The objectives of this work were to assess the effects of litter phytotoxicity and autotoxicity on root proliferation, and to test the hypothesis that DNA is a driver of litter autotoxicity and plant-soil NF. The inhibitory effect of decomposed litter was studied in different bioassays. Litter biochemical changes were evaluated with nuclear magnetic resonance (NMR) spectroscopy. DNA accumulation in litter and soil was measured and DNA toxicity was assessed in laboratory experiments. Undecomposed litter caused nonspecific inhibition of root growth, while autotoxicity was produced by aged litter. The addition of activated carbon (AC) removed phytotoxicity, but was ineffective against autotoxicity. Phytotoxicity was related to known labile allelopathic compounds. Restricted (13) C NMR signals related to nucleic acids were the only ones negatively correlated with root growth on conspecific substrates. DNA accumulation was observed in both litter decomposition and soil history experiments. Extracted total DNA showed evident species-specific toxicity. Results indicate a general occurrence of litter autotoxicity related to the exposure to fragmented self-DNA. The evidence also suggests the involvement of accumulated extracellular DNA in plant-soil NF. Further studies are needed to further investigate this unexpected function of extracellular DNA at the ecosystem level and related cellular and molecular mechanisms. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  18. Soil-atmosphere N2O and CH4 exchanges was suppressed by litter layer in a subtropical secondary forest

    NASA Astrophysics Data System (ADS)

    Cui, J. J.; Lai, D. Y. F.

    2016-12-01

    Forest soil has a great potential in affecting future climate change through biogeochemical cycling and exchanging greenhouse gases (GHGs) with the atmosphere. As a proxy of changing atmospheric CO2 concentration, enhanced litter production arising from CO2 fertilization can affect soil GHG fluxes and induce feedbacks to the climate system. However, these litter-soil- atmosphere interactions remain unclear, especially in subtropical forests. In this study, we carried out static chamber measurements and field manipulations in a subtropical secondary forest in Hong Kong over one year to investigate the temporal variations and controls, as well as the effects of changing litter amounts on soil-atmosphere GHG fluxes. Our results show distinct seasonal pattern of GHG fluxes and soil parameters over the study period. While CO2 flux did not respond significantly to litter manipulation, regression analysis indicates that CO2 flux was regulated by soil temperature and soil moisture. Litter reduction stimulated mean N2O emissions by 105%, and the positive effect was most pronounced during the hot-humid season from May to October. On the other hand, litter addition was found to reduce CH4 uptake by 32%. Our findings suggest that the presence of litter might serve a physical barrier for gas diffusion. It is suggested that the biogeochemical feedback arising from litterfall should be taken into account in simulating the response of forest GHG fluxes to future global change.

  19. Energetic contaminants inhibit plant litter decomposition in soil.

    PubMed

    Kuperman, Roman G; Checkai, Ronald T; Simini, Michael; Sunahara, Geoffrey I; Hawari, Jalal

    2018-05-30

    Individual effects of nitrogen-based energetic materials (EMs) 2,4-dinitrotoluene (2,4-DNT), 2-amino-4,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), nitroglycerin (NG), and 2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (CL-20) on litter decomposition, an essential biologically-mediated soil process, were assessed using Orchard grass (Dactylis glomerata) straw in Sassafras sandy loam (SSL) soil, which has physicochemical characteristics that support "very high" qualitative relative bioavailability for organic chemicals. Batches of SSL soil were separately amended with individual EMs or acetone carrier control. To quantify the decomposition rates, one straw cluster was harvested from a set of randomly selected replicate containers from within each treatment, after 1, 2, 3, 4, 6, and 8 months of exposure. Results showed that soil amended with 2,4-DNT or NG inhibited litter decomposition rates based on the median effective concentration (EC50) values of 1122 mg/kg and 860 mg/kg, respectively. Exposure to 2-ADNT, 4-ADNT or CL-20 amended soil did not significantly affect litter decomposition in SSL soil at ≥ 10,000 mg/kg. These ecotoxicological data will be helpful in identifying concentrations of EMs in soil that present an acceptable ecological risk for biologically-mediated soil processes. Published by Elsevier Inc.

  20. Methods for estimating litter decomposition. Chapter 8

    Treesearch

    Noah J. Karberg; Neal A. Scott; Christian P. Giardina

    2008-01-01

    Litterfall in terrestrial ecosystems represents the primary pathway for nutrient return to soil. Heterotrophic metabolism, facilitated through comminution by small insects and leaching during precipitation events, results in the release of plant litter carbon as CO2 into the atmosphere. The balance between litter inputs and heterotrophic litter...

  1. Marine Litter, Eutrophication and Noise Assessment Tools

    NASA Astrophysics Data System (ADS)

    Palazov, Atanas; Velcheva, Maya; Milkova, Tanya; Slabakova, Violeta; Marinova, Veselka

    2017-04-01

    MARLEN - Marine Litter, Eutrophication and Noise Assessment Tools is a project under the Programme BG02.03: Increased capacity for assessing and predicting environmental status in marine and inland waters, managed by Bulgarian Ministry of environment and waters and co-financed by the Financial Mechanism of the European Economic Area (EEA FM) 2009 - 2014. Project Beneficiary is the Institute of oceanology - Bulgarian Academy of Sciences with two partners: Burgas municipality and Bulgarian Black Sea Basin Directorate. Initial assessment of ecological state of Bulgarian marine waters showed lack of data for some descriptors of MSFD. The main goal of MARLEN is to build up tools for assessment of marine environment by implementing new technologies and best practices for addressing three main areas of interest with lack of marine data in particular: a) Marine litter detection and classification in coastal areas; b) Regular near real time surface water eutrophication monitoring on large aquatory; c) Underwater noise monitoring. Developed tools are an important source of real time, near real time and delay mode marine data for Bulgarian Black Sea waters. The partnership within the project increased capacity for environmental assessments and training of personnel and enhances collaboration between scientific institutes, regional and local authorities. Project results supported implementation of MSFD in Bulgarian marine waters for the benefit of coastal population, marine industry, tourism, marine research and marine spatial planning.

  2. Effects of a silica-based feed supplement on performance, health, and litter quality of growing turkeys.

    PubMed

    Tran, S T; Bowman, M E; Smith, T K

    2015-08-01

    Poor litter quality is a potential challenge to footpad health as well as the primary cause of ammonia volatilization. High ambient ammonia concentration is one of the most significant factors negatively affecting poultry production today. Some minerals have been reported to reduce ammonia release from poultry litter. Silicon dioxide, a highly pure and natural mineral, shows promise in decreasing ammonia volatilization and improving litter quality. The objective of the current study was to investigate the effects of feed-borne silicon dioxide on litter quality and how this impacts bird performance, general health and footpad health throughout a 12-wk posthatching turkey study. Supplementing the diet with silicon dioxide was found to significantly improve turkey BW gain and the efficiency of feed conversion. The severity of footpad dermatitis was monitored throughout the experimental period but no significant effect of diet was seen. The feeding of silicon dioxide reduced litter pH which decreased the conversion of NH4⁺ to NH3 thereby reducing nitrogen losses from litter. It was concluded that, under our study conditions, the feeding of 0.02% silicon dioxide offers potential economic benefits to turkey producers. © 2015 Poultry Science Association Inc.

  3. Interacting Microbe and Litter Quality Controls on Litter Decomposition: A Modeling Analysis

    PubMed Central

    Moorhead, Daryl; Lashermes, Gwenaëlle; Recous, Sylvie; Bertrand, Isabelle

    2014-01-01

    The decomposition of plant litter in soil is a dynamic process during which substrate chemistry and microbial controls interact. We more clearly quantify these controls with a revised version of the Guild-based Decomposition Model (GDM) in which we used a reverse Michaelis-Menten approach to simulate short-term (112 days) decomposition of roots from four genotypes of Zea mays that differed primarily in lignin chemistry. A co-metabolic relationship between the degradation of lignin and holocellulose (cellulose+hemicellulose) fractions of litter showed that the reduction in decay rate with increasing lignin concentration (LCI) was related to the level of arabinan substitutions in arabinoxylan chains (i.e., arabinan to xylan or A∶X ratio) and the extent to which hemicellulose chains are cross-linked with lignin in plant cell walls. This pattern was consistent between genotypes and during progressive decomposition within each genotype. Moreover, decay rates were controlled by these cross-linkages from the start of decomposition. We also discovered it necessary to divide the Van Soest soluble (labile) fraction of litter C into two pools: one that rapidly decomposed and a second that was more persistent. Simulated microbial production was consistent with recent studies suggesting that more rapidly decomposing materials can generate greater amounts of potentially recalcitrant microbial products despite the rapid loss of litter mass. Sensitivity analyses failed to identify any model parameter that consistently explained a large proportion of model variation, suggesting that feedback controls between litter quality and microbial activity in the reverse Michaelis-Menten approach resulted in stable model behavior. Model extrapolations to an independent set of data, derived from the decomposition of 12 different genotypes of maize roots, averaged within <3% of observed respiration rates and total CO2 efflux over 112 days. PMID:25264895

  4. Different pathways but same result? Comparing chemistry and biological effects of burned and decomposed litter

    NASA Astrophysics Data System (ADS)

    Mazzoleni, Stefano; Bonanomi, Giuliano; Incerti, Guido; El-Gawad, Ahmed M. Abd; Sarker, Tushar Chandra; Cesarano, Gaspare; Saulino, Luigi; Saracino, Antonio; Castro Rego, Francisco

    2017-04-01

    Litter burning and biological decomposition are oxidative processes co-occurring in many terrestrial ecosystems, producing organic matter with different chemical properties and differently affecting plant growth and soil microbial activity. Here, we tested the chemical convergence hypothesis (i.e. materials with different initial chemistry tend to converge towards a common profile, with similar biological effects, as the oxidative process advances) for burning and decomposition. We compared the molecular composition of 63 organic materials - 7 litter types either fresh, decomposed for 30, 90, 180 days, or heated at 100, 200, 300, 400, 500 °C - as assessed by 13C NMR. We used litter water extracts (5% dw) as treatments in bioassays on plant (Lepidium sativum) and fungal (Aspergillus niger) growth, and a washed quartz sand amended with litter materials (0.5 % dw) to assess heterotrophic respiration by CO2 flux chamber. We observed different molecular variations for materials either burning (i.e. a sharp increase of aromatic C and a decrease of most other fractions above 200 °C) or decomposing (i.e. early increase of alkyl, methoxyl and N-alkyl C and decrease of O-alkyl and di-O-alkyl C fractions). Soil respiration and fungal growth progressively decreased with litter age and temperature. Plant growth underwent an inhibitory effect by untreated litter, more and less rapidly released over decomposing and burning materials, respectively. Correlation analysis between NMR and bioassay data showed that opposite responses for soil respiration and fungi, compared to plants, are related to essentially the same C molecular types. Our findings suggest a functional convergence of decomposed and burnt organic substrates, emerging from the balance between the bioavailability of labile C sources and the presence of recalcitrant and pyrogenic compounds, oppositely affecting different trophic levels.

  5. Climate change effects on macrofaunal litter decomposition: the interplay of temperature, body masses and stoichiometry.

    PubMed

    Ott, David; Rall, Björn C; Brose, Ulrich

    2012-11-05

    Macrofauna invertebrates of forest floors provide important functions in the decomposition process of soil organic matter, which is affected by the nutrient stoichiometry of the leaf litter. Climate change effects on forest ecosystems include warming and decreasing litter quality (e.g. higher C : nutrient ratios) induced by higher atmospheric CO(2) concentrations. While litter-bag experiments unravelled separate effects, a mechanistic understanding of how interactions between temperature and litter stoichiometry are driving decomposition rates is lacking. In a laboratory experiment, we filled this void by quantifying decomposer consumption rates analogous to predator-prey functional responses that include the mechanistic parameters handling time and attack rate. Systematically, we varied the body masses of isopods, the environmental temperature and the resource between poor (hornbeam) and good quality (ash). We found that attack rates increased and handling times decreased (i) with body masses and (ii) temperature. Interestingly, these relationships interacted with litter quality: small isopods possibly avoided the poorer resource, whereas large isopods exhibited increased, compensatory feeding of the poorer resource, which may be explained by their higher metabolic demands. The combination of metabolic theory and ecological stoichiometry provided critically important mechanistic insights into how warming and varying litter quality may modify macrofaunal decomposition rates.

  6. Temperature response of litter and soil organic matter decomposition is determined by chemical composition of organic material.

    PubMed

    Erhagen, Björn; Öquist, Mats; Sparrman, Tobias; Haei, Mahsa; Ilstedt, Ulrik; Hedenström, Mattias; Schleucher, Jürgen; Nilsson, Mats B

    2013-12-01

    The global soil carbon pool is approximately three times larger than the contemporary atmospheric pool, therefore even minor changes to its integrity may have major implications for atmospheric CO2 concentrations. While theory predicts that the chemical composition of organic matter should constitute a master control on the temperature response of its decomposition, this relationship has not yet been fully demonstrated. We used laboratory incubations of forest soil organic matter (SOM) and fresh litter material together with NMR spectroscopy to make this connection between organic chemical composition and temperature sensitivity of decomposition. Temperature response of decomposition in both fresh litter and SOM was directly related to the chemical composition of the constituent organic matter, explaining 90% and 70% of the variance in Q10 in litter and SOM, respectively. The Q10 of litter decreased with increasing proportions of aromatic and O-aromatic compounds, and increased with increased contents of alkyl- and O-alkyl carbons. In contrast, in SOM, decomposition was affected only by carbonyl compounds. To reveal why a certain group of organic chemical compounds affected the temperature sensitivity of organic matter decomposition in litter and SOM, a more detailed characterization of the (13) C aromatic region using Heteronuclear Single Quantum Coherence (HSQC) was conducted. The results revealed considerable differences in the aromatic region between litter and SOM. This suggests that the correlation between chemical composition of organic matter and the temperature response of decomposition differed between litter and SOM. The temperature response of soil decomposition processes can thus be described by the chemical composition of its constituent organic matter, this paves the way for improved ecosystem modeling of biosphere feedbacks under a changing climate. © 2013 John Wiley & Sons Ltd.

  7. Long-term litter decomposition controlled by manganese redox cycling

    PubMed Central

    Keiluweit, Marco; Nico, Peter; Harmon, Mark E.; Mao, Jingdong; Pett-Ridge, Jennifer; Kleber, Markus

    2015-01-01

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of litter was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn2+ provided by fresh plant litter to produce oxidative Mn3+ species at sites of active decay, with Mn eventually accumulating as insoluble Mn3+/4+ oxides. Formation of reactive Mn3+ species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn3+-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn3+ species in the litter layer. This observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant–soil system may have a profound impact on litter decomposition rates. PMID:26372954

  8. Long-term litter decomposition controlled by manganese redox cycling.

    PubMed

    Keiluweit, Marco; Nico, Peter; Harmon, Mark E; Mao, Jingdong; Pett-Ridge, Jennifer; Kleber, Markus

    2015-09-22

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of litter was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn(2+) provided by fresh plant litter to produce oxidative Mn(3+) species at sites of active decay, with Mn eventually accumulating as insoluble Mn(3+/4+) oxides. Formation of reactive Mn(3+) species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn(3+)-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn(3+) species in the litter layer. This observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant-soil system may have a profound impact on litter decomposition rates.

  9. [Relationships between decomposition rate of leaf litter and initial quality across the alpine timberline ecotone in Western Sichuan, China].

    PubMed

    Yang, Lin; Deng, Chang-chun; Chen Ya-mei; He, Run-lian; Zhang, Jian; Liu, Yang

    2015-12-01

    The relationships between litter decomposition rate and their initial quality of 14 representative plants in the alpine forest ecotone of western Sichuan were investigated in this paper. The decomposition rate k of the litter ranged from 0.16 to 1.70. Woody leaf litter and moss litter decomposed much slower, and shrubby litter decomposed a little faster. Then, herbaceous litters decomposed fastest among all plant forms. There were significant linear regression relationships between the litter decomposition rate and the N content, lignin content, phenolics content, C/N, C/P and lignin/N. Lignin/N and hemicellulose content could explain 78.4% variation of the litter decomposition rate (k) by path analysis. The lignin/N could explain 69.5% variation of k alone, and the direct path coefficient of lignin/N on k was -0.913. Principal component analysis (PCA) showed that the contribution rate of the first sort axis to k and the decomposition time (t) reached 99.2%. Significant positive correlations existed between lignin/N, lignin content, C/N, C/P and the first sort axis, and the closest relationship existed between lignin/N and the first sort axis (r = 0.923). Lignin/N was the key quality factor affecting plant litter decomposition rate across the alpine timberline ecotone, with the higher the initial lignin/N, the lower the decomposition rate of leaf litter.

  10. Statistical analyses of the results of 25 years of beach litter surveys on the south-eastern North Sea coast.

    PubMed

    Schulz, Marcus; Clemens, Thomas; Förster, Harald; Harder, Thorsten; Fleet, David; Gaus, Silvia; Grave, Christel; Flegel, Imme; Schrey, Eckart; Hartwig, Eike

    2015-08-01

    In the North Sea, the amount of litter present in the marine environment represents a severe environmental problem. In order to assess the magnitude of the problem and measure changes in abundance, the results of two beach litter monitoring programmes were compared and analysed for long-term trends applying multivariate techniques. Total beach litter pollution was persistently high. Spatial differences in litter abundance made it difficult to identify long-term trends: Partly more than 8000 litter items year(-1) were recorded on a 100 m long survey site on the island of Scharhörn, while the survey site on the beach on the island of Amrum revealed abundances lower by two orders of magnitude. Beach litter was dominated by plastic with mean proportions of 52%-91% of total beach litter. Non-parametric time series analyses detected many significant trends, which, however, did not show any systematic spatial patterns. Cluster analyses partly led to groupings of beaches according to their expositions to sources of litter, wind and currents. Surveys in short intervals of one to two weeks were found to give higher annual sums of beach litter than the quarterly surveys of the OSPAR method. Surveys at regular intervals of four weeks to five months would make monitoring results more reliable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Effects of forage species and poultry litter application timing on forage preference by horses.

    PubMed

    Clark, J K; Shanks, B C; Jogan, K S; Philipp, D; Coffey, K P; Jack, N E; Caldwell, J D; Rhein, R T

    2016-12-01

    Bermudagrass ( L.) is a familiar forage in the equine industry and teff () is gaining popularity as well. However, it is unclear if the application of poultry litter as a fertilizer affects palatability of these forages in horses. Therefore, the objective of this study was to determine if forage species and timing of litter application as a fertilizer has an effect on preference by horses. Hay treatments were arranged in a 2 × 3 factorial treatment arrangement consisting of teff and bermudagrass harvested after no poultry litter application (NL), poultry litter applied to stubble immediately after removal of the previous cutting (L0), or poultry litter applied 14 d after the previous cutting (L14). Mature, stock-type geldings ( = 5; 480 ± 52.9 kg) were used in this study arranged as a balanced incomplete block design. Horses were offered different combinations of 4 of the 6 total forages daily for 3 d in each of 3 evaluation periods that immediately followed a 10-d adaptation period. Each forage was offered at half of the total daily DMI as measured during the last 5 d of the 10-d adaptation period to encourage selection among the 4 forages. Each hay offered was randomly allocated to a corner and suspended in hay nets over muck buckets in the corners of each stall. Horses were individually housed in 3.6- by 3.6-m indoor stalls with sand bedding and access to 3.6- by 7.6-m outdoor runs. Along with hay, horses were offered oats twice daily at 0.125% of BW at each feeding. Dry matter intake was greater ( < 0.01) for bermudagrass than for teff and for NL and L0 treatments compared with L14 treatments. Horses spent more ( < 0.01) time consuming bermudagrass compared with teff. However, there were no differences ( ≥ 0.25) in time spent consuming hay across litter treatments. Therefore, horses may prefer bermudagrass to teff and later application of poultry litter may affect voluntary intake by horses. However, all forages were mature, which may have impacted total

  12. The effect of dietary protein and phosphorus on ammonia concentration and litter composition in broilers.

    PubMed

    Ferguson, N S; Gates, R S; Taraba, J L; Cantor, A H; Pescatore, A J; Straw, M L; Ford, M J; Burnham, D J

    1998-08-01

    An experiment was conducted to determine whether broiler litter concentration of N and P and equilibrium NH3 gas concentration can be reduced by reducing dietary CP and P levels and supplementing with amino acids and phytase, respectively, without adversely affecting bird performance. Equilibrium NH3 gas concentration above the litter was measured. The experiment was divided into a starter period (1 to 21 d) and grower period (22 to 42 d), each having two different CP and P levels in a 2 x 2 factorial arrangement. The CP treatments consisted of a control with a mean CP of 204 and 202 g/kg for starter and grower periods, respectively, and a low CP diet with means of 188 and 183 g/kg, respectively, but with similar amino acid levels as the control. The P treatments comprised starter and grower control diets containing means of 6.7 and 6.3 g/kg P, respectively, and low P treatment means of 5.8 and 5.4 g/kg P supplemented with 1.0 g/kg phytase. Reducing starter diet CP by 16 g/kg reduced weight gain by 3.5% and, hence, body weight at 21 d of age, but did not affect feed intake or feed efficiency. Reducing P did not affect feed intake and weight gain, but improved feed efficiency by 2.0%. Responses in feed intake and efficiency to CP depended on the level of dietary P. For the grower period there were no significant differences in feed intake, weight gain, and feed efficiency, nor in body weight at 42 d of age, after correcting for 21-d body weight, between CP and P treatments. There were significant (P < 0.001) reductions in litter N and P concentrations, but not equilibrium NH3 gas concentration, moisture content, or pH, for low CP and P diets. Mean equilibrium NH3 gas concentration was 63 ppm. Litter N concentration was reduced 16.3% with the low CP diets, and litter P by 23.2% in low P treatments. The results suggest that dietary manipulation shows merit for reducing litter N and P concentrations while maintaining acceptable production performance from broilers.

  13. Combined Effects of Dissolved Nutrients and Oxygen on Plant Litter Decomposition and Associated Fungal Communities.

    PubMed

    Gomes, Patrícia Pereira; Ferreira, Verónica; Tonin, Alan M; Medeiros, Adriana Oliveira; Júnior, José Francisco Gonçalves

    2018-05-01

    Aquatic ecosystems worldwide have been substantially altered by human activities, which often induce changes in multiple factors that can interact to produce complex effects. Here, we evaluated the combined effects of dissolved nutrients (nitrogen [N] and phosphorus [P]; three levels: concentration found in oligotrophic streams in the Cerrado biome, 10× and 100× enriched) and oxygen (O 2 ; three levels: hypoxic [4% O 2 ], depleted [55% O 2 ], and saturated [96% O 2 ]) on plant litter decomposition and associated fungal decomposers in laboratory microcosms simulating stream conditions under distinct scenarios of water quality deterioration. Senescent leaves of Maprounea guianensis were incubated for 10 days in an oligotrophic Cerrado stream to allow microbial colonization and subsequently incubated in microcosms for 21 days. Leaves lost 1.1-3.0% of their initial mass after 21 days, and this was not affected either by nutrients or oxygen levels. When considering simultaneous changes in nutrients and oxygen concentrations, simulating increased human pressure, fungal biomass accumulation, and sporulation rates were generally inhibited. Aquatic hyphomycete community structure was also affected by changes in nutrients and oxygen availability, with stronger effects found in hypoxic treatments than in depleted or saturated oxygen treatments. This study showed that the effects of simultaneous changes in the availability of dissolved nutrients and oxygen in aquatic environments can influence the activity and composition of fungal communities, although these effects were not translated into changes in litter decomposition rates.

  14. Litter fall from shrubs in the northern Majove Desert

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Strojan, C.L.; Turner,F.B.; Castetter, R.

    1979-10-01

    Plant litter was collected in traps from 8 to 10 replicates each of Ambrosia dumosa, Ephedra nevadensis, Krameria parvifolia, Larrea tradentata, Lycium andersonii, and Lycium pallidum in Rock Valley, southern Nevada, USA. Collections were made at biweekly to monthly intervals from 1975 to 1977 and handsorted into leaves, stems, flowers, and fruits. Litter fall was generally correlated with annual rainfall, which was low in 1975 (62 mm), high in 1976 (223 mm), and close to the longterm mean in 1977 (141 mm). Leaves were generally the largest litter category, followed by stems, fruits, and flowers. Large sample variations were found,more » particularly for reproductive parts. Aboveground litter fall from the six species, which comprise approx. = 82% of pernnial plant biomass and approx. = 81% of shrub cover in Rock Valley, was about 117 kg/ha in 1975 and 318 kg/ha in 1976. Total aboveground litter fall for Rock Valley (all perennial and annual plants) was estimated to be 194 kg/ha in 1975 and 530 kg/ha in 1976. Distinct litter fall patterns occurred for shrub species and litter categories. Most litter fell during the summer months, with individual species peaks reflecting particular phenologies. Significant amounts of live aboveground biomass were shed as litter. Amounts of litter from the six species ranged from 7 to 83% of their respective live aboveground biomass.« less

  15. Leaf Litter Chemistry Drives the Structure and Composition of Soil Testate Amoeba Communities in a Tropical Montane Rainforest of the Ecuadorian Andes.

    PubMed

    Krashevska, Valentyna; Sandmann, Dorothee; Marian, Franca; Maraun, Mark; Scheu, Stefan

    2017-10-01

    We investigated the role of leaf litter chemistry and richness in affecting testate amoeba communities of tropical rainforest in the Ecuadorian Andes. Litterbags containing leaf litter from four dominating tree species (Clusia sp., Myrcia pubescens, Graffenrieda emarginata, and Cecropia andina) with richness 1, 2, and 4 species were established and exposed in the field for 12 months at 2000 m a.s.l. Chemical elements and compounds of leaf litter were analyzed before exposure. At the end of exposure, microbial biomass and litter mass loss were measured, and living testate amoeba species number, density, biomass, and community composition were determined. In total, 125 testate amoeba species colonized the litter in litterbags. The results suggest that high litter nitrogen and low lignin concentrations are indicators of high litter quality for testate amoebae density and species richness. Their species number and density significantly declined in the order 1 > 4 > 2 leaf litter species and varied with leaf litter chemistry being at a maximum in high-quality single leaf litter species and low in low-quality leaf litter. Further, the addition of litter of high-quality to low-quality litter increased testate amoebae biomass and density; however, the values did not exceed the ones in single high-quality litter treatments. Moreover, the structure of testate amoeba communities varied with litter chemistry, with Fe, Na, lignin, and litter C-to-N ratio being of major importance, and indicating that litter chemistry reflects habitat quality for testate amoebae. Overall, the data show that leaf litter chemistry overrides leaf litter richness in structuring testate amoeba communities.

  16. Plant diversity does not buffer drought effects on early-stage litter mass loss rates and microbial properties.

    PubMed

    Vogel, Anja; Eisenhauer, Nico; Weigelt, Alexandra; Scherer-Lorenzen, Michael

    2013-09-01

    Human activities are decreasing biodiversity and changing the climate worldwide. Both global change drivers have been shown to affect ecosystem functioning, but they may also act in concert in a non-additive way. We studied early-stage litter mass loss rates and soil microbial properties (basal respiration and microbial biomass) during the summer season in response to plant species richness and summer drought in a large grassland biodiversity experiment, the Jena Experiment, Germany. In line with our expectations, decreasing plant diversity and summer drought decreased litter mass loss rates and soil microbial properties. In contrast to our hypotheses, however, this was only true for mass loss of standard litter (wheat straw) used in all plots, and not for plant community-specific litter mass loss. We found no interactive effects between global change drivers, that is, drought reduced litter mass loss rates and soil microbial properties irrespective of plant diversity. High mass loss rates of plant community-specific litter and low responsiveness to drought relative to the standard litter indicate that soil microbial communities were adapted to decomposing community-specific plant litter material including lower susceptibility to dry conditions during summer months. Moreover, higher microbial enzymatic diversity at high plant diversity may have caused elevated mass loss of standard litter. Our results indicate that plant diversity loss and summer drought independently impede soil processes. However, soil decomposer communities may be highly adapted to decomposing plant community-specific litter material, even in situations of environmental stress. Results of standard litter mass loss moreover suggest that decomposer communities under diverse plant communities are able to cope with a greater variety of plant inputs possibly making them less responsive to biotic changes. © 2013 John Wiley & Sons Ltd.

  17. Long-term litter decomposition controlled by manganese redox cycling

    DOE PAGES

    Keiluweit, Marco; Nico, Peter S.; Harmon, Mark; ...

    2015-09-08

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of littermore » was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn 2+ provided by fresh plant litter to produce oxidative Mn 3+ species at sites of active decay, with Mn eventually accumulating as insoluble Mn 3+/4+ oxides. Formation of reactive Mn 3+ species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn 3+-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn 3+ species in the litter layer. As a result, this observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant–soil system may have a profound impact on litter decomposition rates.« less

  18. How does litter become soil organic matter? Tracing the fate of needle- and root-derived soil organic matter through 10 years of decomposition

    NASA Astrophysics Data System (ADS)

    Hicks Pries, Caitlin E.; Hatton, Pierre-Joseph; Castanha, Cristina; Bird, Jeffrey A.; Torn, Margaret S.

    2014-05-01

    All soil organic matter (SOM) is derived from plant material. However, little is known about the process by which plant litter becomes SOM (as opposed to the better-studied controls on rates of carbon (C) and nitrogen (N) loss from litter). We investigated the transformations of above- and below-ground plant inputs in soil over ten years, and whether litter type (roots versus needles) affects the form and location of litter-derived C and N in soil after 10 years. We placed 15N and 13C-labeled Pinus ponderosa needle and fine root litter in the Blodgett Experimental Forest in the Sierra Nevada foothills in 2001. A two-way factorial design was used with needle and root litter placed into O and A soil horizons. Litter was inserted into the given horizon within soil mesocosms (10.2 cm diameter x 24 cm long PVC) that had two 5 x 5 cm mesh windows to allow contact with the surrounding soil. After 0.5, 1, 1.5, 4.5, and 10 years, the mesocosms were collected from the field. Isotopes were used to measure the percent recovery of the litter C and N in the bulk soil of the O and A horizons. To investigate mineral associations of the added litter C and N after 10 years, we sequentially fractionated the soils by density. The fractions were a free light fraction (<1.75 g cm-3), a fraction dominated by secondary phyllosilicate minerals (1.75-2.5 g cm-3), a quartz and feldspar-dominated fraction (2.5-2.78 g cm-3), and a fraction dominated by biotite with kaolinite and iron oxide coatings (>2.78 g cm-3). These fractions differ in the type of organic matter they are associated with according to C:N ratios and molecular characterization via FTIR. The biotite fraction had the lowest C:N ratios, indicating it was the most microbially-processed. After 10 years, more root litter C (about 44%) was retained in the soil than needle litter C (about 28%). In line with slower rates of decomposition, root C and N remained in the particulate (>2 mm) fraction and the free light fraction longer than

  19. Effect of litter quality on foot pad dermatitis, hock burns and breast blisters in broiler breeders during the production period.

    PubMed

    Kaukonen, Eija; Norring, Marianna; Valros, Anna

    2016-12-01

    Foot pad dermatitis and hock burn lesions are a form of contact dermatitis, a condition affecting skin areas in contact with unsuitable or irritating material. Contact dermatitis is a common problem, reducing the welfare of broilers, and is believed to also affect broiler breeders. However, there is very little research on contact dermatitis in breeders. This study followed the severity of foot pad lesions in broiler breeders throughout the production period. At slaughter the presence of hock burns and breast blisters was also determined. In addition, changes in litter condition over time and the impact of litter quality on foot pads were evaluated. The study was performed on 10 broiler breeder farms, including altogether 18 flocks. Foot pads of 100 hens per flock were assessed at the end of rearing period, three times during the production period, and at slaughter. Foot pad and hock lesions, as well as litter condition were scored on a 5-point scale. Litter quality was evaluated as pH, moisture and ammonia content. The condition of foot pads deteriorated towards slaughter age, with the occurrence of severe lesions reaching a maximum of 64% on average at slaughter. Hock lesions and breast blisters were rare. The litter layer became drier over time. Although poorer litter condition and wetness influenced foot pad health negatively, the effect on severe lesions was not significant. We also observed a negative effect on foot pad condition of larger slat areas. In conclusion, maintaining good litter quality alone is not enough to ensure healthy foot pads in broiler breeders.

  20. Potential energy expenditure by litter-roosting bats associated with temperature under leaf litter during winter

    Treesearch

    Roger W. Perry

    2013-01-01

    In temperate portions of North America, some bats that remain active during winter undergo short periods of hibernation below leaf litter on the forest floor during episodes of below-freezing weather. These winter roosts may provide above-freezing conditions, but the thermal conditions under leaf litter are unclear. Further, little is known of the relationship between...

  1. Biochemical Composition Suggests Different Roles of Leaf Litter and Fine Roots in Soil Carbon Formation

    NASA Astrophysics Data System (ADS)

    Xia, M.; Pregitzer, K. S.; Talhelm, A. F.

    2012-12-01

    stimulate the decay of lignin by providing required energy. Therefore, fine roots of Acer saccharum have a relatively recalcitrant nature based on their distinct biochemical composition, suggesting fine roots may be the major driver of soil carbon formation in the ecosystems we studied. Litter type and N addition had significant interactions on lignin, holocellulose, and NSC (P< 0.05), indicating these traits of different litter types respond differently to N addition. In leaf litter, the concentrations of lignin, NSC, and bound CT were affected by N addition (P< 0.05). By contrast, N addition only reduced the soluble protein concentration in fine roots (P< 0.05). Hence, substrate quality of leaf litter and fine roots responds differently to the simulated N deposition, and may eventually lead to different responses in decomposition pattern. This is one of few studies comparing the detailed biochemical profile of leaf litter and fine roots in a dominant tree species. Different biochemical traits of fine roots and leaf litter may reflect the different specializations for their physiological functions. This work highlights the importance of fine root in the soil carbon formation due to its recalcitrant nature, and emphasizes the necessity of differentiating the responses of leaf litter and fine root decompositions to environmental changes when modeling biogeochemical cycles.

  2. From the litter up and the sky down: Perspectives on urban ...

    EPA Pesticide Factsheets

    The structure of the urban forest represents the complex product of local biophysical conditions, socio-economic milieu, people preferences and management with rare counterparts in rural forests. However, urban forest structure, as similarly observed in rural forests, affects key ecological and hydrological processes as well as the plethora of organisms regulating these processes. This seminar talk will firstly present key mechanisms regulating urban eco-hydrological processes “from a litter up” perspective. In particular, fine scale effects of urban forest structure upon i) organic matter decomposition, and comminution, ii) community-assembly of decomposers, detritivores, and ecosystem engineers (i.e. bacteria, litter-dwelling macrofauna, ants), and iii) stormwater runoff infiltration and interception will be discussed. The second part of this intervention will look at the structure of the urban forest “from a sky down” perspective. Recent findings from large scale LiDAR investigations will be presented to discuss social and biophysical drivers affecting urban forest structure at sub-continental scale, as well as short-term tree loss dynamics across residential landscapes, and how these can potentially affect eco-hydrological processes at large scale. Urban forest structure, as similarly observed in rural forests, affects key ecological and hydrological processes as well as the plethora of organisms regulating these processes.

  3. Plastic litter accumulation on high-water strandline of urban beaches in Mumbai, India.

    PubMed

    Jayasiri, H B; Purushothaman, C S; Vennila, A

    2013-09-01

    Today, almost every beach on every coastline is threatened by human activities. The inadequate recycling and poor management of waste in developing countries has resulted in considerable quantities of plastic contaminating beaches. Though India has long coastline of 5,420 km along the mainland with 43 % of sandy beaches, data on litter accumulation, particularly the plastics, which are one of the most common and persistent pollutants in marine environment, are scanty. The abundance and distribution of plastic litter was quantitatively assessed in four sandy beaches in Mumbai, India, bimonthly from May 2011 to March 2012. Triplicates of 2 × 2 m (4 m(2)) quadrats were sampled in each beach with a total of 72 quadrats. Overall, average abundance of 11.6 items m(-2) (0.25-282.5 items m(-2)) and 3.24 g m(-2) (0.27-15.53 g m(-2)) plastic litter was recorded in Mumbai beaches. Plastic litter accumulation significantly varied temporally and spatially at p = 0.05. Significantly higher plastic litter accumulation was recorded in Juhu beach. Furthermore, the highest abundance by weight was recorded in November and May numerically. More than 80 % of plastic particles were within the size range of 5-100 mm both by number and weight. Moreover, coloured plastics were predominant with 67 % by number of items and 51 % by weight. Probably, the intense use of beaches for recreation, tourism, and religious activities has increased the potential for plastic contamination in urban beaches in Mumbai.

  4. Marine litter in submarine canyons of the Bay of Biscay

    NASA Astrophysics Data System (ADS)

    van den Beld, Inge M. J.; Guillaumont, Brigitte; Menot, Lénaïck; Bayle, Christophe; Arnaud-Haond, Sophie; Bourillet, Jean-François

    2017-11-01

    Marine litter is a matter of increasing concern worldwide, from shallow seas to the open ocean and from beaches to the deep-seafloor. Indeed, the deep sea may be the ultimate repository of a large proportion of litter in the ocean. We used footage acquired with a Remotely Operated Vehicle (ROV) and a towed camera to investigate the distribution and composition of litter in the submarine canyons of the Bay of Biscay. This bay contains many submarine canyons housing Vulnerable Marine Ecosystems (VMEs) such as scleractinian coral habitats. VMEs are considered to be important for fish and they increase the local biodiversity. The objectives of the study were to investigate and discuss: (i) litter density, (ii) the principal sources of litter, (iii) the influence of environmental factors on the distribution of litter, and (iv) the impact of litter on benthic communities. Litter was found in all 15 canyons and at three sites on the edge of the continental shelf/canyon, in 25 of 29 dives. The Belle-île and Arcachon Canyons contained the largest amounts of litter, up to 12.6 and 9.5 items per 100 images respectively. Plastic items were the most abundant (42%), followed by fishing-related items (16%). The litter had both a maritime and a terrestrial origin. The main sources could be linked to fishing activities, major shipping lanes and river discharges. Litter appeared to accumulate at water depths of 801-1100 m and 1401-1700 m. In the deeper of these two depth ranges, litter accumulated on a geologically structured area, accounting for its high frequency at this depth. A larger number of images taken in areas of coral in the shallower of these two depth ranges may account for the high frequency of litter detection at this depth. A larger number of litter items, including plastic objects in particular, were observed on geological structures and in coral areas than on areas of bare substratum. The distribution of fishing-related items was similar for the various types of

  5. Water quality benefits of subsurface-banded poultry litter

    USDA-ARS?s Scientific Manuscript database

    Broiler chicken production is an important industry in Alabama and several other states. Broiler litter is commonly used as a fertilizer on pastures and cropland. This litter has commonly been land-applied near the broiler houses and this has resulted in long-term repeated application of litter to...

  6. Litter Species Composition and Topographic Effects on Fuels and Modeled Fire Behavior in an Oak-Hickory Forest in the Eastern USA.

    PubMed

    Dickinson, Matthew B; Hutchinson, Todd F; Dietenberger, Mark; Matt, Frederick; Peters, Matthew P

    2016-01-01

    Mesophytic species (esp. Acer rubrum) are increasingly replacing oaks (Quercus spp.) in fire-suppressed, deciduous oak-hickory forests of the eastern US. A pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to burn at lower intensities. Species effects, however, are confounded by topographic gradients that affect overstory composition and fuel bed decomposition. To examine the separate and combined effects of litter species composition and topography on surface fuel beds, we conducted a common garden experiment in oak-hickory forests of the Ohio Hills. Each common garden included beds composed of mostly oak and mostly maple litter, representative of oak- and maple-dominated stands, respectively, and a mixture of the two. Beds were replenished each fall for four years. Common gardens (N = 16) were established at four topographic positions (ridges, benches on south- and northeast-facing slopes, and stream terraces) at each of four sites. Litter source and topographic position had largely independent effects on fuel beds and modeled fire dynamics after four years of development. Loading (kg m-2) of the upper litter layer (L), the layer that primarily supports flaming spread, was least in more mesic landscape positions and for maple beds, implying greater decomposition rates for those situations. Bulk density in the L layer (kg m-3) was least for oak beds which, along with higher loading, would promote fire spread and fireline intensity. Loading and bulk density of the combined fermentation and humic (FH) layers were least on stream terrace positions but were not related to species. Litter- and FH-layer moistures during a 5-day dry-down period after a rain event were affected by time and topographic effects while litter source effects were not evident. Characteristics of flaming combustion determined with a cone calorimeter pointed to greater fireline

  7. Experimental study of terrestrial plant litter interaction with aqueous solutions

    NASA Astrophysics Data System (ADS)

    Fraysse, F.; Pokrovsky, O. S.; Meunier, J.-D.

    2010-01-01

    Quantification of silicon and calcium recycling by plants is hampered by the lack of physico-chemical data on reactivity of plant litter in soil environments. We applied a laboratory experimental approach for determining the silica and calcium release rates from litter of typical temperate and boreal plants: pine ( Pinus laricio), birch ( Betula pubescens), larch ( Larix gmelinii), elm ( Ulmus laevis Pall.), tree fern ( Dicksonia squarrosa), and horsetail (Equisetum arvense) in 0.01 M NaCl solutions, pH of 2-10 and temperature equals to 5, 25 and 40 °C. Open system, mixed-flow reactors equipped with dialysis compartment and batch reactors were used. Comparative measurements were performed on intact larch needles and samples grounded during different time, sterilized or not and with addition or not of sodium azide in order to account for the effect of surface to mass ratio and possible microbiological activity on the litter dissolution rates. Litter degradation results suggest that the silica release rate is independent on dissolved organic carbon release (cell breakdown) which implies the presence of phytoliths in a pure "inorganic" pool not complexed with organic matter. Calcium and DOC are released at the very first stage of litter dissolution while Si concentration increases gradually suggesting the presence of Ca and Si in two different pools. The dry-weight normalized dissolution rate at circum-neutral pH range (approx. 1-10 μmol/g DW/day) is 2 orders of magnitude higher than the rates of Si release from common soil minerals (kaolinite, smectite, illite). Minimal Ca release rates evaluated from batch and mixed-flow reactors are comparable with those of most reactive soil minerals such as calcite and apatite, and several orders of magnitude higher than the dissolution rates of major rock-forming silicates (feldspars, pyroxenes). The activation energy for Si liberation from plant litter is approx. 50 kJ/mol which is comparable with that of surface

  8. Joint Analysis of Binomial and Continuous Traits with a Recursive Model: A Case Study Using Mortality and Litter Size of Pigs

    PubMed Central

    Varona, Luis; Sorensen, Daniel

    2014-01-01

    This work presents a model for the joint analysis of a binomial and a Gaussian trait using a recursive parametrization that leads to a computationally efficient implementation. The model is illustrated in an analysis of mortality and litter size in two breeds of Danish pigs, Landrace and Yorkshire. Available evidence suggests that mortality of piglets increased partly as a result of successful selection for total number of piglets born. In recent years there has been a need to decrease the incidence of mortality in pig-breeding programs. We report estimates of genetic variation at the level of the logit of the probability of mortality and quantify how it is affected by the size of the litter. Several models for mortality are considered and the best fits are obtained by postulating linear and cubic relationships between the logit of the probability of mortality and litter size, for Landrace and Yorkshire, respectively. An interpretation of how the presence of genetic variation affects the probability of mortality in the population is provided and we discuss and quantify the prospects of selecting for reduced mortality, without affecting litter size. PMID:24414548

  9. Phosphorus availability modulates the toxic effect of silver on aquatic fungi and leaf litter decomposition.

    PubMed

    Funck, J Arce; Clivot, H; Felten, V; Rousselle, P; Guérold, F; Danger, M

    2013-11-15

    The functioning of forested headwater streams is intimately linked to the decomposition of leaf litter by decomposers, mainly aquatic hyphomycetes, which enables the transfer of allochthonous carbon to higher trophic levels. Evaluation of this process is being increasingly used as an indicator of ecosystem health and ecological integrity. Yet, even though the individual impacts of contaminants and nutrient availability on decomposition have been well studied, the understanding of their combined effects remains limited. In the current study, we investigated whether the toxic effects of a reemerging contaminant, silver (Ag), on leaf litter decomposition could be partly overcome in situations where microorganisms were benefitting from high phosphorus (P) availability, the latter being a key chemical element that often limits detritus decomposition. We also investigated whether these interactive effects were mediated by changes in the structure of the aquatic hyphomycete community. To verify these hypotheses, leaf litter decomposition by a consortium of ten aquatic hyphomycete species was followed in a microcosm experiment combining five Ag contamination levels and three P concentrations. Indirect effects of Ag and P on the consumption of leaf litter by the detritivorous crustacean, Gammarus fossarum, were also evaluated. Ag significantly reduced decomposition but only at the highest concentration tested, independently of P level. By contrast, P and Ag interactively affected fungal biomass. Both P level and Ag concentrations shaped microbial communities without significantly affecting the overall species richness. Finally, the levels of P and Ag interacted significantly on G. fossarum feeding rates, high [Ag] reducing litter consumption and low P availability tending to intensify the feeding rate. Given the high level of contaminant needed to impair the decomposition process, it is unlikely that a direct effect of Ag on leaf litter decomposition could be observed in

  10. Litter decay rates are determined by lignin chemistry

    Treesearch

    Jennifer M. Talbot; Daniel J. Yelle; James Nowick; Kathleen K. Treseder

    2011-01-01

    Litter decay rates are often correlated with the initial lignin:N or lignin:cellulose content of litter, suggesting that interactions between lignin and more labile compounds are important controls over litter decomposition. The chemical composition of lignin may influence these interactions, if lignin physically or chemically protects labile components from microbial...

  11. The effect of increasing the dietary valine-to-lysine ratio on sow metabolism, milk production, and litter growth.

    PubMed

    Strathe, A V; Bruun, T S; Zerrahn, J-E; Tauson, A-H; Hansen, C F

    2016-01-01

    A study was conducted to investigate the effect of increasing the dietary valine-to-lysine ratio (Val:Lys) for lactating sows weaning more than 12 piglets. Five hundred fifty-eight sows (parity 1 to 4) were allotted to 6 dietary treatments from 2 d postpartum, when litters were standardized to 14 piglets. Diets were analyzed to have a total dietary Val:Lys of 0.84, 0.86, 0.88, 0.90, 0.95, or 0.99:1. On all 558 sows, BW, back fat thickness (BF), and litter weight were registered at d 108 of gestation and d 2 and 25 (weaning) postpartum. On a subsample of 72 sows, additional measurements were made: sow BW and BF were measured on d 17 and litter weight was measured on d 10 and 17, and blood and urine samples were collected weekly. The litter size at weaning was not affected by the dietary Val:Lys ( = 0.23) and, on average, the sows weaned 13.0 ± 1.1 piglets. Average daily gain of the litter (2.93 ± 0.53 kg/d; = 0.84), litter weight at weaning ( = 0.67), the average milk yield (11.3 ± 1.4 kg/d; = 0.49), and milk contents of fat ( = 0.57), protein ( = 0.18), and lactose ( = 0.20) were not affected by the dietary Val:Lys. Increasing the dietary Val:Lys increased the milk concentration of Val ( < 0.05) and Ile ( < 0.01). The change in sow BW and BF were similar for all sows from d 2 to 17, d 17 to 25, and d 2 to 25 ( > 0.05). During lactation, sows, on average, had a BW and back fat loss of 22.1 ± 12.7 kg and 2.9 ± 1.7 mm, respectively. Plasma concentrations of glucose ( = 0.26), lactate ( = 0.95), urea N ( = 0.84), NEFA ( = 0.24), and creatinine ( = 0.42); urine concentration of creatinine ( = 0.57); and concentrations of AA in whole blood ( > 0.05) were not affected by the dietary Val:Lys. In conclusion, there was no effect of increasing the total dietary Val:Lys above 0.84:1 on sow metabolism and litter performance during lactation.

  12. The afterlife of interspecific indirect genetic effects: genotype interactions alter litter quality with consequences for decomposition and nutrient dynamics.

    PubMed

    Genung, Mark A; Bailey, Joseph K; Schweitzer, Jennifer A

    2013-01-01

    Aboveground-belowground linkages are recognized as divers of community dynamics and ecosystem processes, but the impacts of plant-neighbor interactions on these linkages are virtually unknown. Plant-neighbor interactions are a type of interspecific indirect genetic effect (IIGE) if the focal plant's phenotype is altered by the expression of genes in a neighboring heterospecific plant, and IIGEs could persist after plant senescence to affect ecosystem processes. This perspective can provide insight into how plant-neighbor interactions affect evolution, as IIGEs are capable of altering species interactions and community composition over time. Utilizing genotypes of Solidago altissima and Solidago gigantea, we experimentally tested whether IIGEs that had affected living focal plants would affect litter decomposition rate, as well as nitrogen (N) and phosphorous (P) dynamics after the focal plant senesced. We found that species interactions affected N release and genotype interactions affected P immobilization. From a previous study we knew that neighbor genotype influenced patterns of biomass allocation for focal plants. Here we extend those previous results to show that these changes in biomass allocation altered litter quality, that then altered rates of decomposition and nutrient cycling. Our results provide insights into above- and belowground linkages by showing that, through their effects on plant litter quality (e.g., litter lignin:N), IIGEs can have afterlife effects, tying plant-neighbor interactions to ecosystem processes. This holistic approach advances our understanding of decomposition and nutrient cycling by showing that evolutionary processes (i.e., IIGEs) can influence ecosystem functioning after plant senescence. Because plant traits are determined by the combined effects of genetic and environmental influences, and because these traits are known to affect decomposition and nutrient cycling, we suggest that ecosystem processes can be described as gene

  13. The Afterlife of Interspecific Indirect Genetic Effects: Genotype Interactions Alter Litter Quality with Consequences for Decomposition and Nutrient Dynamics

    PubMed Central

    Genung, Mark A.; Bailey, Joseph K.; Schweitzer, Jennifer A.

    2013-01-01

    Aboveground-belowground linkages are recognized as divers of community dynamics and ecosystem processes, but the impacts of plant-neighbor interactions on these linkages are virtually unknown. Plant-neighbor interactions are a type of interspecific indirect genetic effect (IIGE) if the focal plant’s phenotype is altered by the expression of genes in a neighboring heterospecific plant, and IIGEs could persist after plant senescence to affect ecosystem processes. This perspective can provide insight into how plant-neighbor interactions affect evolution, as IIGEs are capable of altering species interactions and community composition over time. Utilizing genotypes of Solidago altissima and Solidago gigantea, we experimentally tested whether IIGEs that had affected living focal plants would affect litter decomposition rate, as well as nitrogen (N) and phosphorous (P) dynamics after the focal plant senesced. We found that species interactions affected N release and genotype interactions affected P immobilization. From a previous study we knew that neighbor genotype influenced patterns of biomass allocation for focal plants. Here we extend those previous results to show that these changes in biomass allocation altered litter quality, that then altered rates of decomposition and nutrient cycling. Our results provide insights into above- and belowground linkages by showing that, through their effects on plant litter quality (e.g., litter lignin:N), IIGEs can have afterlife effects, tying plant-neighbor interactions to ecosystem processes. This holistic approach advances our understanding of decomposition and nutrient cycling by showing that evolutionary processes (i.e., IIGEs) can influence ecosystem functioning after plant senescence. Because plant traits are determined by the combined effects of genetic and environmental influences, and because these traits are known to affect decomposition and nutrient cycling, we suggest that ecosystem processes can be described as

  14. Influence of raised plastic floors compared with pine shaving litter on environment and Pekin duck condition.

    PubMed

    Karcher, D M; Makagon, M M; Fraley, G S; Fraley, S M; Lilburn, M S

    2013-03-01

    Commercial poultry production management practices have been under increased public scrutiny driven by concerns for food safety and animal welfare. Within the United States, wood shavings and raised plastic floors are common flooring systems used in duck production. It is intuitive that each flooring type would present different management challenges influencing physical characteristics of growing ducks. This study evaluated the relationship between flooring type and duck condition during the winter. Random samples of 20 ducks from 5 predetermined areas (n = 100) were examined in commercial duck houses (n = 9, litter; n = 11, raised plastic slats). Ducks were assessed at 7, 21, and 32 d of age for eye, nostril, and feather cleanliness, feather and foot pad quality, and gait. The data were analyzed to determine the proportion of ducks with a given score. In both housing types, the proportion of 0 scores for foot pad quality improved during the production cycle (P < 0.0001). Feather hygiene declined with age in ducks reared on litter flooring, whereas ducks reared on slatted flooring had cleaner feathers at d 32 (P < 0.011). With the exception of foot pad scores, the majority of ducks had no detectable problems for any single trait. The only main effect due to flooring pertained to feather quality with the proportion of ducks having a 0 or 1 score greater in litter flooring systems than slats (P < 0.05). Overall, the condition of ducks reared, regardless of flooring system, was considered to be good.

  15. Gap locations influence the release of carbon, nitrogen and phosphorus in two shrub foliar litter in an alpine fir forest

    PubMed Central

    He, Wei; Wu, Fuzhong; Yang, Wanqin; Zhang, Danju; Xu, Zhenfeng; Tan, Bo; Zhao, Yeyi; Justine, Meta Francis

    2016-01-01

    Gap formation favors the growth of understory plants and affects the decomposition process of plant debris inside and outside of gaps. Little information is available regarding how bioelement release from shrub litter is affected by gap formation during critical periods. The release of carbon (C), nitrogen (N), and phosphorus (P) in the foliar litter of Fargesia nitida and Salix paraplesia in response to gap locations was determined in an alpine forest of the eastern Qinghai-Tibet Plateau via a 2-year litter decomposition experiment. The daily release rates of C, N, and P increased from the closed canopy to the gap centers during the two winters, the two later growing seasons and the entire 2 years, whereas this trend was reversed during the two early growing seasons. The pairwise ratios among C, N, and P converged as the litter decomposition proceeded. Compared with the closed canopy, the gap centers displayed higher C:P and N:P ratio but a lower C:N ratio as the decomposition proceeded. Alpine forest gaps accelerate the release of C, N, and P in decomposing shrub litter, implying that reduced snow cover resulting from vanishing gaps may inhibit the release of these elements in alpine forests. PMID:26906762

  16. Plastic litter from shotgun ammunition on Danish coastlines - Amounts and provenance.

    PubMed

    Kanstrup, Niels; Balsby, Thorsten J S

    2018-06-01

    Plastic litter in the marine environment is a major global issue. Discarded plastic shotgun ammunition shells and discharged wads are an unwelcome addition and feature among the top ten litter items found on reference beaches in Denmark. To understand this problem, its scale and origins, collections were made by volunteers along Danish coastal shorelines. In all 3669 plastic ammunition items were collected at 68 sites along 44.6 km of shoreline. The collected items were scored for characteristic variables such as gauge and length, shot type, and the legibility of text, the erosion, and the presence of metallic components. Scores for characteristics were related to the site, area, and season and possible influences discussed. The prevalence of collected plastic shotgun litter ranges from zero to 41 items per 100 m with an average of 3.7 items per 100 m. Most ammunition litter on Danish coasts originates from hunting on Danish coastal waterbodies, but a small amount may come from further afield. North Sea coasts are the most distinctive suggesting the possible contribution of long distance drift as well as the likelihood that such litter can persist in marine habitats for decades. The pathway from initial discard to eventual wash-up and collection depends on the physical properties of plastic components, marine tides and currents, coastal topography and shoreline vegetation. Judging from the disintegration of the cartridge and the wear and decomposition of components, we conclude that there is a substantial supply of polluting plastic ammunition materials that has and will accumulate. These plastic items pose a hazard to marine ecosystems and wash up on coasts for many years to come. We recommend that responsible managers, hunters and ammunition manufacturers will take action now to reduce the problem and, thereby, protect ecosystems, wildlife and the sustainability of hunting. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Effects of Plant Functional Group Loss on Soil Microbial Community and Litter Decomposition in a Steppe Vegetation.

    PubMed

    Xiao, Chunwang; Zhou, Yong; Su, Jiaqi; Yang, Fan

    2017-01-01

    Globally, many terrestrial ecosystems are experiencing a rapid loss of biodiversity. Continued improvements in our understanding of interrelationships between plant diversity and soil microbes are critical to address the concern over the consequences of the decline in biodiversity on ecosystem functioning and services. By removing forbs, or grasses, or, to an extreme scenario, both forbs and grasses in a steppe vegetation in Inner Mongolia, we studied how plant functional group (PFG) loss affects soil microbial community composition using phospholipid fatty acid analysis (PLFA) and litter decomposition using a litter-bag method. PFG loss significantly decreased above- and below-ground plant biomass, soil microbial biomass carbon (SMBC) and nitrogen (SMBN), but had no effect on the ratio of SMBC to SMBN. Although the ratio of fungal to bacterial PLFAs remained unaffected, PFG loss significantly reduced the amount of bacterial, fungal, and total PLFAs. PFG loss decreased litter monthly mass loss and decay constant, and such decrease was significant when both forbs and grasses were removed. Our results provide robust evidence that PFG loss in grassland ecosystem can lead to a rapid response of soil microbial activity which may affect litter decomposition and soil nutrient cycling, suggesting that the assessment of plant-microbe interactions in soils is an integral component of ecosystem response to biodiversity loss.

  18. Preliminary investigation of the transport of small plastic litter along a vegetated riverbank

    NASA Astrophysics Data System (ADS)

    Liu, Da; Valyrakis, Manousos

    2017-04-01

    Plastics are widely used in consumer products, due to its low cost, low weight and high durability compared to other types of materials. Contamination of marine ecosystems due to plastics (including microplastics) is a challenge that has received a lot of attention due to the significant risks it poses for the environment and human health. Plastics find their way to the ocean from land via the river system. Studying and obtaining a better understanding of the mechanisms contributing to the fate of plastic litter is therefore important in proactively devising methods to reduce their quantity or produce designs to trap plastic pollutants and prevent them from entering the ocean through estuaries. In this context, it is a common observation of hydraulic practitioners and field geomorphologists, that plastic litter can be trapped within riparian vegetation patches along streams or canals, which can be washed away in periods of high flows. To this goal this study aims to use a series of purpose specific physical experiments to examine the mechanisms of dispersion of plastic litter along the water surface of a channel with simulated riparian vegetation. The set of experiments are conducted in a recirculating flume with rigid riverbank and riparian vegetation modeled by a large number of acrylic rods, placed on the top of the riverbank section. Six different sizes of pieces of Styrofoam are used to simulate plastic litter. These are released from different locations upstream and in the vicinity of the riparian vegetation for various configurations (linear, staggered and random) of characteristic solid density. The trajectory of the plastic litter is recorded with a camera offering a top view of the arrangement. From the analysis of this a variety of results are obtained including transport metrics (including transport velocity and time to trapping) and litter-trapping location. The relation between the size of the litter, the vegetation configuration and the traveling

  19. UVB exposure does not accelerate rates of litter decomposition in a semiarid riparian ecosystem

    USDA-ARS?s Scientific Manuscript database

    Aboveground litter decomposition is controlled mainly by substrate quality and climate factors across terrestrial ecosystems, but photodegradation from exposure to high-intensity ultraviolet-B (UVB) radiation may also be important in arid and semi-arid environments. We investigated the interactive e...

  20. Situating Arab-Israeli artisanal fishermen's perceptions of marine litter in a socio-institutional and socio-cultural context.

    PubMed

    Brennan, Ruth E; Portman, Michelle E

    2017-02-15

    Understanding the mental constructs underlying people's social responses, decisions and behaviors is crucial to defining the governance challenges faced in dealing with marine anthropogenic litter. Using interactive governance theory, this study provides qualitative insights into how a small group of Arab-Israeli artisanal fishermen perceive marine litter and its impact (system to be governed) in the context of the socio-institutional structures (governing system) which manage waste and aim to protect the surrounding environment. It demonstrates that, until the relationships between local people and the various governing institutions are transformed, there is little hope for citizen cooperation in reducing marine litter long-term in the case-study site. More generally, underlying narratives and politics playing out at a local level need to be understood in order to identify which interventions are likely to be effective and which are not. An intervention checklist to assess the potential effectiveness of a marine litter intervention is proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Within-litter variation in birth weight: impact of nutritional status in the sow.

    PubMed

    Yuan, Tao-lin; Zhu, Yu-hua; Shi, Meng; Li, Tian-tian; Li, Na; Wu, Guo-yao; Bazer, Fuller W; Zang, Jian-jun; Wang, Feng-lai; Wang, Jun-jun

    2015-06-01

    Accompanying the beneficial improvement in litter size from genetic selection for high-prolificacy sows, within-litter variation in birth weight has increased with detrimental effects on post-natal growth and survival due to an increase in the proportion of piglets with low birth-weight. Causes of within-litter variation in birth weight include breed characteristics that affect uterine space, ovulation rate, degree of maturation of oocytes, duration of time required for ovulation, interval between ovulation and fertilization, uterine capacity for implantation and placentation, size and efficiency of placental transport of nutrients, communication between conceptus/fetus and maternal systems, as well as nutritional status and environmental influences during gestation. Because these factors contribute to within-litter variation in birth weight, nutritional status of the sow to improve fetal-placental development must focus on the following three important stages in the reproductive cycle: pre-mating or weaning to estrus, early gestation and late gestation. The goal is to increase the homogeneity of development of oocytes and conceptuses, decrease variations in conceptus development during implantation and placentation, and improve birth weights of newborn piglets. Though some progress has been made in nutritional regulation of within-litter variation in the birth weight of piglets, additional studies, with a focus on and insights into molecular mechanisms of reproductive physiology from the aspects of maternal growth and offspring development, as well as their regulation by nutrients provided to the sow, are urgently needed.

  2. Litter type control on soil C and N stabilization dynamics in a temperate forest.

    PubMed

    Hatton, Pierre-Joseph; Castanha, Cristina; Torn, Margaret S; Bird, Jeffrey A

    2015-03-01

    While plant litters are the main source of soil organic matter (SOM) in forests, the controllers and pathways to stable SOM formation remain unclear. Here, we address how litter type ((13) C/(15) N-labeled needles vs. fine roots) and placement-depth (O vs. A horizon) affect in situ C and N dynamics in a temperate forest soil after 5 years. Litter type rather than placement-depth controlled soil C and N retention after 5 years in situ, with belowground fine root inputs greatly enhancing soil C (x1.4) and N (x1.2) retention compared with aboveground needles. While the proportions of added needle and fine root-derived C and N recovered into stable SOM fractions were similar, they followed different transformation pathways into stable SOM fractions: fine root transfer was slower than for needles, but proportionally more of the remaining needle-derived C and N was transferred into stable SOM fractions. The stoichiometry of litter-derived C vs. N within individual SOM fractions revealed the presence at least two pools of different turnover times (per SOM fraction) and emphasized the role of N-rich compounds for long-term persistence. Finally, a regression approach suggested that models may underestimate soil C retention from litter with fast decomposition rates. © 2014 John Wiley & Sons Ltd.

  3. Alum treatment of poultry litter: decomposition and nitrogen dynamics.

    PubMed

    Gilmour, J T; Koehler, M A; Cabrera, M L; Szajdak, L; Moore, P A

    2004-01-01

    While the poultry industry is a major economic benefit to several areas in the USA, land application of poultry litter to recycle nutrients can lead to impaired surface and ground water quality. Amending poultry litter with alum [Al3(SO4)2 x 14H2O] has received considerable attention as a method of economically reducing ammonia volatilization in the poultry house and soluble phosphorus in runoff waters. The objective of this study was to characterize the effect of alum on broiler litter decomposition and N dynamics under laboratory conditions. Litter that had been amended with alum in the poultry house after each of the first four of five flock cycles (Experiment I) and litter that had been amended with alum after removal from a poultry house after the third flock cycle (Experiment II) were compared with unamended litter in separate studies. The litters in Experiment I were surface-applied to simulate application to grasslands, while the litters in Experiment II were incorporated to simulate application to conventionally tilled crops. The only statistically significant differences in decomposition due to alum occurred early in Experiment II and the differences were small. The only statistically significant differences in net N mineralization, soil inorganic N, and soil NH4+-N in either experiment was found in Experiment I after 70 d of incubation where soil inorganic N was significantly greater for the alum treatment. Thus, alum had little effect on decomposition or N dynamics. Results of many of the studies on litter not amended with alum should be applicable to litters amended with alum to reduce P availability.

  4. Leaf and root litter decomposition is discontinued at high altitude tropical montane rainforests contributing to carbon sequestration.

    PubMed

    Marian, Franca; Sandmann, Dorothee; Krashevska, Valentyna; Maraun, Mark; Scheu, Stefan

    2017-08-01

    We investigated how altitude affects the decomposition of leaf and root litter in the Andean tropical montane rainforest of southern Ecuador, that is, through changes in the litter quality between altitudes or other site-specific differences in microenvironmental conditions. Leaf litter from three abundant tree species and roots of different diameter from sites at 1,000, 2,000, and 3,000 m were placed in litterbags and incubated for 6, 12, 24, 36, and 48 months. Environmental conditions at the three altitudes and the sampling time were the main factors driving litter decomposition, while origin, and therefore quality of the litter, was of minor importance. At 2,000 and 3,000 m decomposition of litter declined for 12 months reaching a limit value of ~50% of initial and not decomposing further for about 24 months. After 36 months, decomposition commenced at low rates resulting in an average of 37.9% and 44.4% of initial remaining after 48 months. In contrast, at 1,000 m decomposition continued for 48 months until only 10.9% of the initial litter mass remained. Changes in decomposition rates were paralleled by changes in microorganisms with microbial biomass decreasing after 24 months at 2,000 and 3,000 m, while varying little at 1,000 m. The results show that, irrespective of litter origin (1,000, 2,000, 3,000 m) and type (leaves, roots), unfavorable microenvironmental conditions at high altitudes inhibit decomposition processes resulting in the sequestration of carbon in thick organic layers.

  5. Fungal contamination of poultry litter: a public health problem.

    PubMed

    Viegas, C; Carolino, E; Malta-Vacas, J; Sabino, R; Viegas, S; Veríssimo, C

    2012-01-01

    Although numerous studies have been conducted on microbial contaminants associated with various stages related to poultry and meat products processing, only a few reported on fungal contamination of poultry litter. The goals of this study were to (1) characterize litter fungal contamination and (2) report the incidence of keratinophilic and toxigenic fungi presence. Seven fresh and 14 aged litter samples were collected from 7 poultry farms. In addition, 27 air samples of 25 litters were also collected through impaction method, and after laboratory processing and incubation of collected samples, quantitative colony-forming units (CFU/m³) and qualitative results were obtained. Twelve different fungal species were detected in fresh litter and Penicillium was the most frequent genus found (59.9%), followed by Alternaria (17.8%), Cladosporium (7.1%), and Aspergillus (5.7%). With respect to aged litter, 19 different fungal species were detected, with Penicillium sp. the most frequently isolated (42.3%), followed by Scopulariopsis sp. (38.3%), Trichosporon sp. (8.8%), and Aspergillus sp. (5.5%). A significant positive correlation was found between litter fungal contamination (CFU/g) and air fungal contamination (CFU/m³). Litter fungal quantification and species identification have important implications in the evaluation of potential adverse health risks to exposed workers and animals. Spreading of poultry litter in agricultural fields is a potential public health concern, since keratinophilic (Scopulariopsis and Fusarium genus) as well as toxigenic fungi (Aspergillus, Fusarium, and Penicillium genus) were isolated.

  6. Influence of nitrogen additions on litter decomposition, nutrient dynamics, and enzymatic activity of two plant species in a peatland in Northeast China.

    PubMed

    Song, Yanyu; Song, Changchun; Ren, Jiusheng; Tan, Wenwen; Jin, Shaofei; Jiang, Lei

    2018-06-01

    Nitrogen (N) availability affects litter decomposition and nutrient dynamics, especially in N-limited ecosystems. We investigated the response of litter decomposition to N additions in Eriophorum vaginatum and Vaccinium uliginosum peatlands. These two species dominate peatlands in Northeast China. In 2012, mesh bags containing senesced leaf litter of Eriophorum vaginatum and Vaccinium uliginosum were placed in N addition plots and sprayed monthly for two years with NH 4 NO 3 solution at dose rates of 0, 6, 12, and 24gNm -2 year -1 (CK, N1, N2 and N3, respectively). Mass loss, N and phosphorus (P) content, and enzymatic activity were measured over time as litter decomposed. In the control plots, V. uliginosum litter decomposed faster than E. vaginatum litter. N1, N2, and N3 treatments increased the mass losses of V. uliginosum litter by 6%, 9%, and 4% respectively, when compared with control. No significant influence of N additions was found on the decomposition of E. vaginatum litter. However, N and P content in E. vaginatum litter and V. uliginosum litter significantly increased with N additions. Moreover, N additions significantly promoted invertase and β-glucosidase activity in E. vaginatum and V. uliginosum litter. However, only in V. uliginosum litter was polyphenol oxidase activity significantly enhanced. Our results showed that initial litter quality and polyphenol oxidase activity influence the response of plant litter to N additions in peatland ecosystems. Increased N availability may change peatland soil N and P cycling by enhancing N and P immobilization during litter decomposition. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Biochar lowers ammonia emission and improves nitrogen retention in poultry litter composting.

    PubMed

    Agyarko-Mintah, Eunice; Cowie, Annette; Van Zwieten, Lukas; Singh, Bhupinder Pal; Smillie, Robert; Harden, Steven; Fornasier, Flavio

    2017-03-01

    The poultry industry produces abundant quantities of nutrient-rich litter, much of which is composted before use as a soil amendment. However, a large proportion of nitrogen (N) in poultry litter is lost via volatilisation during composting, with negative environmental and economic consequences. This study examined the effect of incorporating biochar during composting of poultry litter on ammonia (NH 3 ) volatilisation and N retention. Biochars produced at 550°C from greenwaste (GWB) and poultry litter (PLB) feedstocks were co-composted with a mixture of raw poultry litter and sugarcane straw [carbon (C):N ratio 10:1] in compost bins. Ammonia emissions accounted for 17% of the total N (TN) lost from the control and 12-14% from the biochar-amended compost. The TN emitted as NH 3 , as a percentage of initial TN, was significantly lower (P<0.05) i.e. by 60% and 55% in the compost amended with GWB and PLB, respectively, relative to the control. The proportion of N retained in the finished compost, as a percentage of initial TN, was 84%, 78% and 67% for the GWB, PLB and nil biochar control, respectively. Lower concentration of dissolved organic C (DOC) together with higher activity of beta-glucosidase and leucine-aminopeptidase were found in the GWB-amended compost (cf. control). It is hypothesized that lower NH 3 emission in the GWB-amended compost was caused not just by the higher surface area of this biochar but could also be related to greater incorporation of ammonium (NH 4 + ) in organic compounds during microbial utilisation of DOC. Furthermore, the GWB-amended compost retained more NH 4 + at the end of composting than the PLB-amended compost. Results showed that addition of biochar, especially GWB, generated multiple benefits in composting of poultry litter: decrease of NH 3 volatilisation, decrease in NH 3 toxicity towards microorganisms, and improved N retention, thus enhancing the fertiliser value of the composted litter. It is suggested that the latter

  8. Early stage litter decomposition across biomes

    Treesearch

    Ika Djukic; Sebastian Kepfer-Rojas; Inger Kappel Schmidt; Klaus Steenberg Larsen; Claus Beier; Björn Berg; Kris Verheyen; Adriano Caliman; Alain Paquette; Alba Gutiérrez-Girón; Alberto Humber; Alejandro Valdecantos; Alessandro Petraglia; Heather Alexander; Algirdas Augustaitis; Amélie Saillard; Ana Carolina Ruiz Fernández; Ana I. Sousa; Ana I. Lillebø; Anderson da Rocha Gripp; André-Jean Francez; Andrea Fischer; Andreas Bohner; Andrey Malyshev; Andrijana Andrić; Andy Smith; Angela Stanisci; Anikó Seres; Anja Schmidt; Anna Avila; Anne Probst; Annie Ouin; Anzar A. Khuroo; Arne Verstraeten; Arely N. Palabral-Aguilera; Artur Stefanski; Aurora Gaxiola; Bart Muys; Bernard Bosman; Bernd Ahrends; Bill Parker; Birgit Sattler; Bo Yang; Bohdan Juráni; Brigitta Erschbamer; Carmen Eugenia Rodriguez Ortiz; Casper T. Christiansen; E. Carol Adair; Céline Meredieu; Cendrine Mony; Charles A. Nock; Chi-Ling Chen; Chiao-Ping Wang; Christel Baum; Christian Rixen; Christine Delire; Christophe Piscart; Christopher Andrews; Corinna Rebmann; Cristina Branquinho; Dana Polyanskaya; David Fuentes Delgado; Dirk Wundram; Diyaa Radeideh; Eduardo Ordóñez-Regil; Edward Crawford; Elena Preda; Elena Tropina; Elli Groner; Eric Lucot; Erzsébet Hornung; Esperança Gacia; Esther Lévesque; Evanilde Benedito; Evgeny A. Davydov; Evy Ampoorter; Fabio Padilha Bolzan; Felipe Varela; Ferdinand Kristöfel; Fernando T. Maestre; Florence Maunoury-Danger; Florian Hofhansl; Florian Kitz; Flurin Sutter; Francisco Cuesta; Francisco de Almeida Lobo; Franco Leandro de Souza; Frank Berninger; Franz Zehetner; Georg Wohlfahrt; George Vourlitis; Geovana Carreño-Rocabado; Gina Arena; Gisele Daiane Pinha; Grizelle González; Guylaine Canut; Hanna Lee; Hans Verbeeck; Harald Auge; Harald Pauli; Hassan Bismarck Nacro; Héctor A. Bahamonde; Heike Feldhaar; Heinke Jäger; Helena C. Serrano; Hélène Verheyden; Helge Bruelheide; Henning Meesenburg; Hermann Jungkunst; Hervé Jactel; Hideaki Shibata; Hiroko Kurokawa; Hugo López Rosas; Hugo L. Rojas Villalobos; Ian Yesilonis; Inara Melece; Inge Van Halder; Inmaculada García Quirós; Isaac Makelele; Issaka Senou; István Fekete; Ivan Mihal; Ivika Ostonen; Jana Borovská; Javier Roales; Jawad Shoqeir; Jean-Christophe Lata; Jean-Paul Theurillat; Jean-Luc Probst; Jess Zimmerman; Jeyanny Vijayanathan; Jianwu Tang; Jill Thompson; Jiří Doležal; Joan-Albert Sanchez-Cabeza; Joël Merlet; Joh Henschel; Johan Neirynck; Johannes Knops; John Loehr; Jonathan von Oppen; Jónína Sigríður Þorláksdóttir; Jörg Löffler; José-Gilberto Cardoso-Mohedano; José-Luis Benito-Alonso; Jose Marcelo Torezan; Joseph C. Morina; Juan J. Jiménez; Juan Dario Quinde; Juha Alatalo; Julia Seeber; Jutta Stadler; Kaie Kriiska; Kalifa Coulibaly; Karibu Fukuzawa; Katalin Szlavecz; Katarína Gerhátová; Kate Lajtha; Kathrin Käppeler; Katie A. Jennings; Katja Tielbörger; Kazuhiko Hoshizaki; Ken Green; Lambiénou Yé; Laryssa Helena Ribeiro Pazianoto; Laura Dienstbach; Laura Williams; Laura Yahdjian; Laurel M. Brigham; Liesbeth van den Brink; Lindsey Rustad; al. et

    2018-01-01

    Through litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies...

  9. Evaluation of the Caravelle litter retrieval system.

    DOT National Transportation Integrated Search

    1988-01-01

    Based on observations, the Caravelle Litter Technologies, Inc's., demonstration of its litter retrieval equipment it was concluded that use of the equipment on highways open to traffic would require extensive and expensive traffic control. The machin...

  10. Conspecific Leaf Litter-Mediated Effect of Conspecific Adult Neighborhood on Early-Stage Seedling Survival in A Subtropical Forest.

    PubMed

    Liu, Heming; Shen, Guochun; Ma, Zunping; Yang, Qingsong; Xia, Jianyang; Fang, Xiaofeng; Wang, Xihua

    2016-11-25

    Conspecific adults have strong negative effect on the survival of nearby early-stage seedlings and thus can promote species coexistence by providing space for the regeneration of heterospecifics. The leaf litter fall from the conspecific adults, and it could mediate this conspecific negative adult effect. However, field evidence for such effect of conspecific leaf litter remains absent. In this study, we used generalized linear mixed models to assess the effects of conspecific leaf litter on the early-stage seedling survival of four dominant species (Machilus leptophylla, Litsea elongate, Acer pubinerve and Distylium myricoides) in early-stage seedlings in a subtropical evergreen broad-leaved forest in eastern China. Our results consistently showed that the conspecific leaf litter of three species negatively affected the seedling survival. Meanwhile, the traditional conspecific adult neighborhood indices failed to detect this negative conspecific adult effect. Our study revealed that the accumulation of conspecific leaf litter around adults can largely reduce the survival rate of nearby seedlings. Ignoring it could result in underestimation of the importance of negative density dependence and negative species interactions in the natural forest communities.

  11. Larch Litter Removal Has No Significant Effect On Runoff

    Treesearch

    Richard S. Startz; David N. Tolsted

    1974-01-01

    Runoff was measured on paired litter-removed, litter-left plots in an 11-year-old European larch plantation. On five of the six pairs of plots, the plot with the litter left intact yielded more runoff. however, the differences were neither statistically nor hydrologically significant.

  12. Soil respiration as affected by long-term broiler litter application to a udult in the ozark highlands.

    PubMed

    McMullen, Richard L; Brye, Kristofor R; Gbur, Edward E

    2015-01-01

    The United States produced 8.4 billion broiler chickens () and an estimated 10.1 to 14.3 million Mg of broiler litter (BL) in 2012. Arkansas' production of 1 billion broilers in 2012 produced an estimated 1.2 to 1.7 million Mg of BL, most of which was concentrated in the Ozark Highlands region of northwest Arkansas. Increased CO release from soils associated with agricultural practices has generated concerns regarding the contribution of certain agricultural management practices to global warming. The objectives of this study were to evaluate the effects of long-term (>6 yr) BL application to a Udult on soil respiration and annual C emissions and to determine the predictability of soil respiration based on soil temperature and moisture in the Ozark Highlands region of northwest Arkansas. Soil respiration was measured routinely between May 2009 and May 2012 in response to annual BL application rates of 0, 5.6, and 11.2 Mg dry litter ha that began in 2003. Soil respiration varied ( < 0.01) with BL rate, measurement date, and year. Additions of BL stimulated respiration after application, and rainfall events after dry-soil conditions stimulated respiration in all years. Soil temperature at the 10-cm depth, 0- to 6-cm soil volumetric water content (VWC), and annual CO-C emissions were unaffected ( > 0.05) by BL application rate but differed ( < 0.01) among study years. Multiple regression indicated that soil respiration could be reasonably predicted using 2-cm-depth soil temperature (T) and the product of T and VWC as predictors ( = 0.52; < 0.01). Results indicate that organic amendments, such as BL, can stimulate release of CO from the soil to the atmosphere, potentially negatively affecting atmospheric greenhouse gas concentrations; thus, there may be application rates above which the benefits of organic amendments may be diminished by adverse environmental effects. Improved BL management strategies are needed to lessen the loss of CO from BL-amended soils. Copyright

  13. Drought and detritivores determine leaf litter decomposition in calcareous streams of the Ebro catchment (Spain).

    PubMed

    Monroy, Silvia; Menéndez, Margarita; Basaguren, Ana; Pérez, Javier; Elosegi, Arturo; Pozo, Jesús

    2016-12-15

    Drought, an important environmental factor affecting the functioning of stream ecosystems, is likely to become more prevalent in the Mediterranean region as a consequence of climate change and enhanced water demand. Drought can have profound impacts on leaf litter decomposition, a key ecosystem process in headwater streams, but there is still limited information on its effects at the regional scale. We measured leaf litter decomposition across a gradient of aridity in the Ebro River basin. We deployed coarse- and fine-mesh bags with alder and oak leaves in 11 Mediterranean calcareous streams spanning a range of over 400km, and determined changes in discharge, water quality, leaf-associated macroinvertebrates, leaf quality and decomposition rates. The study streams were subject to different degrees of drought, specific discharge (Ls -1 km -2 ) ranging from 0.62 to 9.99. One of the streams dried out during the experiment, another one reached residual flow, whereas the rest registered uninterrupted flow but with different degrees of flow variability. Decomposition rates differed among sites, being lowest in the 2 most water-stressed sites, but showed no general correlation with specific discharge. Microbial decomposition rates were not correlated with final nutrient content of litter nor to fungal biomass. Total decomposition rate of alder was positively correlated to the density and biomass of shredders; that of oak was not. Shredder density in alder bags showed a positive relationship with specific discharge during the decomposition experiment. Overall, the results point to a complex pattern of litter decomposition at the regional scale, as drought affects decomposition directly by emersion of bags and indirectly by affecting the functional composition and density of detritivores. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Litter Species Composition and Topographic Effects on Fuels and Modeled Fire Behavior in an Oak-Hickory Forest in the Eastern USA

    PubMed Central

    Hutchinson, Todd F.; Dietenberger, Mark; Matt, Frederick; Peters, Matthew P.

    2016-01-01

    Mesophytic species (esp. Acer rubrum) are increasingly replacing oaks (Quercus spp.) in fire-suppressed, deciduous oak-hickory forests of the eastern US. A pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to burn at lower intensities. Species effects, however, are confounded by topographic gradients that affect overstory composition and fuel bed decomposition. To examine the separate and combined effects of litter species composition and topography on surface fuel beds, we conducted a common garden experiment in oak-hickory forests of the Ohio Hills. Each common garden included beds composed of mostly oak and mostly maple litter, representative of oak- and maple-dominated stands, respectively, and a mixture of the two. Beds were replenished each fall for four years. Common gardens (N = 16) were established at four topographic positions (ridges, benches on south- and northeast-facing slopes, and stream terraces) at each of four sites. Litter source and topographic position had largely independent effects on fuel beds and modeled fire dynamics after four years of development. Loading (kg m-2) of the upper litter layer (L), the layer that primarily supports flaming spread, was least in more mesic landscape positions and for maple beds, implying greater decomposition rates for those situations. Bulk density in the L layer (kg m-3) was least for oak beds which, along with higher loading, would promote fire spread and fireline intensity. Loading and bulk density of the combined fermentation and humic (FH) layers were least on stream terrace positions but were not related to species. Litter- and FH-layer moistures during a 5-day dry-down period after a rain event were affected by time and topographic effects while litter source effects were not evident. Characteristics of flaming combustion determined with a cone calorimeter pointed to greater fireline

  15. Intrapopulation Genotypic Variation of Foliar Secondary Chemistry during Leaf Senescence and Litter Decomposition in Silver Birch (Betula pendula)

    PubMed Central

    Paaso, Ulla; Keski-Saari, Sarita; Keinänen, Markku; Karvinen, Heini; Silfver, Tarja; Rousi, Matti; Mikola, Juha

    2017-01-01

    Abundant secondary metabolites, such as condensed tannins, and their interpopulation genotypic variation can remain through plant leaf senescence and affect litter decomposition. Whether the intrapopulation genotypic variation of a more diverse assortment of secondary metabolites equally persists through leaf senescence and litter decomposition is not well understood. We analyzed concentrations of intracellular phenolics, epicuticular flavonoid aglycones, epicuticular triterpenoids, condensed tannins, and lignin in green leaves, senescent leaves and partly decomposed litter of silver birch, Betula pendula. Broad-sense heritability (H2) and coefficient of genotypic variation (CVG) were estimated for metabolites in senescent leaves and litter using 19 genotypes selected from a B. pendula population in southern Finland. We found that most of the secondary metabolites remained through senescence and decomposition and that their persistence was related to their chemical properties. Intrapopulation H2 and CVG for intracellular phenolics, epicuticular flavonoid aglycones and condensed tannins were high and remarkably, increased from senescent leaves to decomposed litter. The rank of genotypes in metabolite concentrations was persistent through litter decomposition. Lignin was an exception, however, with a diminishing genotypic variation during decomposition, and the concentrations of lignin and condensed tannins had a negative genotypic correlation in the senescent leaves. Our results show that secondary metabolites and their intrapopulation genotypic variation can for the most part remain through leaf senescence and early decomposition, which is a prerequisite for initial litter quality to predict variation in litter decomposition rates. Persistent genotypic variation also opens an avenue for selection to impact litter decomposition in B. pendula populations through acting on their green foliage secondary chemistry. The negative genotypic correlations and diminishing

  16. Intrapopulation Genotypic Variation of Foliar Secondary Chemistry during Leaf Senescence and Litter Decomposition in Silver Birch (Betula pendula).

    PubMed

    Paaso, Ulla; Keski-Saari, Sarita; Keinänen, Markku; Karvinen, Heini; Silfver, Tarja; Rousi, Matti; Mikola, Juha

    2017-01-01

    Abundant secondary metabolites, such as condensed tannins, and their interpopulation genotypic variation can remain through plant leaf senescence and affect litter decomposition. Whether the intrapopulation genotypic variation of a more diverse assortment of secondary metabolites equally persists through leaf senescence and litter decomposition is not well understood. We analyzed concentrations of intracellular phenolics, epicuticular flavonoid aglycones, epicuticular triterpenoids, condensed tannins, and lignin in green leaves, senescent leaves and partly decomposed litter of silver birch, Betula pendula . Broad-sense heritability ( H 2 ) and coefficient of genotypic variation ( CV G ) were estimated for metabolites in senescent leaves and litter using 19 genotypes selected from a B. pendula population in southern Finland. We found that most of the secondary metabolites remained through senescence and decomposition and that their persistence was related to their chemical properties. Intrapopulation H 2 and CV G for intracellular phenolics, epicuticular flavonoid aglycones and condensed tannins were high and remarkably, increased from senescent leaves to decomposed litter. The rank of genotypes in metabolite concentrations was persistent through litter decomposition. Lignin was an exception, however, with a diminishing genotypic variation during decomposition, and the concentrations of lignin and condensed tannins had a negative genotypic correlation in the senescent leaves. Our results show that secondary metabolites and their intrapopulation genotypic variation can for the most part remain through leaf senescence and early decomposition, which is a prerequisite for initial litter quality to predict variation in litter decomposition rates. Persistent genotypic variation also opens an avenue for selection to impact litter decomposition in B. pendula populations through acting on their green foliage secondary chemistry. The negative genotypic correlations and

  17. The Impact of Coffee and Pasture Agriculture on Predatory and Omnivorous Leaf-Litter Ants

    PubMed Central

    Dias, Nivia da Silva; Zanetti, Ronald; Santos, Mônica Silva; Peñaflor, Maria Fernanda Gomes Villalba; Broglio, Sônia Maria Forti; Delabie, Jacques Hubert Charles

    2013-01-01

    Ants are known to function as reliable biological indicators for habitat impact assessment. They play a wide range of ecological roles depending on their feeding and nesting habits. By clustering ants in guilds, it is possible both to assess how agriculture and forest fragmentation can disturb ant communities and to predict the ecological impacts due to losses of a specific guild. This study aimed at determining the impact of non-shaded coffee and pasture agriculture on predatory and omnivorous guilds of leaf-litter ants of Atlantic Forest fragments in Minas Gerais, Brazil. Both coffee and pasture agriculture influenced leaf-litter ant community, although coffee was more disruptive than pasture. Coffee agriculture not only disturbed the diversity of predatory ants, but also negatively affected the number of predatory and omnivorous ants when compared to forest fragments. In contrast, pasture agriculture only disrupted the abundance of predatory ants. Fragment edges skirting crops were negatively affected in terms of leaf-litter ant abundance, but not diversity. Cluster analysis showed that forest fragments were similar irrespective of the cultivation, but the borders were similar to the crop. The study assessed agriculture impact by surveying ant guilds, and revealed that the predatory guild is more susceptible than omnivorous ants. PMID:23902334

  18. Exposure to the leaf litter microbiome of healthy adults protects seedlings from pathogen damage.

    PubMed

    Christian, Natalie; Herre, Edward Allen; Mejia, Luis C; Clay, Keith

    2017-07-12

    It is increasingly recognized that microbiota affect host health and physiology. However, it is unclear what factors shape microbiome community assembly in nature, and how microbiome assembly can be manipulated to improve host health. All plant leaves host foliar endophytic fungi, which make up a diverse, environmentally acquired fungal microbiota. Here, we experimentally manipulated assembly of the cacao tree ( Theobroma cacao ) fungal microbiome in nature and tested the effect of assembly outcome on host health. Using next-generation sequencing, as well as culture-based methods coupled with Sanger sequencing, we found that manipulating leaf litter exposure and location within the forest canopy significantly altered microbiome composition in cacao. Exposing cacao seedlings to leaf litter from healthy conspecific adults enriched the seedling microbiome with Colletotrichum tropicale , a fungal endophyte known to enhance pathogen resistance of cacao seedlings by upregulating host defensive pathways. As a result, seedlings exposed to healthy conspecific litter experienced reduced pathogen damage. Our results link processes that affect the assembly and composition of microbiome communities to their functional consequences for host success, and have broad implications for understanding plant-microbe interactions. Deliberate manipulation of the plant-fungal microbiome also has potentially important applications for cacao production and other agricultural systems in general. © 2017 The Author(s).

  19. The impact of coffee and pasture agriculture on predatory and omnivorous leaf-litter ants.

    PubMed

    Dias, Nivia da Silva; Zanetti, Ronald; Santos, Mônica Silva; Peñaflor, Maria Fernanda Gomes Villalba; Broglio, Sônia Maria Forti; Delabie, Jacques Hubert Charles

    2013-01-01

    Ants are known to function as reliable biological indicators for habitat impact assessment. They play a wide range of ecological roles depending on their feeding and nesting habits. By clustering ants in guilds, it is possible both to assess how agriculture and forest fragmentation can disturb ant communities and to predict the ecological impacts due to losses of a specific guild. This study aimed at determining the impact of non-shaded coffee and pasture agriculture on predatory and omnivorous guilds of leaf-litter ants of Atlantic Forest fragments in Minas Gerais, Brazil. Both coffee and pasture agriculture influenced leaf-litter ant community, although coffee was more disruptive than pasture. Coffee agriculture not only disturbed the diversity of predatory ants, but also negatively affected the number of predatory and omnivorous ants when compared to forest fragments. In contrast, pasture agriculture only disrupted the abundance of predatory ants. Fragment edges skirting crops were negatively affected in terms of leaf-litter ant abundance, but not diversity. Cluster analysis showed that forest fragments were similar irrespective of the cultivation, but the borders were similar to the crop. The study assessed agriculture impact by surveying ant guilds, and revealed that the predatory guild is more susceptible than omnivorous ants.

  20. Public participation in wilderness and backcountry litter control: a review of research and management experience.

    Treesearch

    Robert M. Muth; Roger N. Clark

    1978-01-01

    This paper describes the application of the Incentive System for Litter Control to wilderness and backcountry environments. Based on research, observation, and management experience, a set of procedures was developed and is presented here. Additional management considerations are discussed.

  1. Anthropogenic marine litter composition in coastal areas may be a predictor of potentially invasive rafting fauna

    PubMed Central

    Borrell Pichs, Yaisel J.; García-Vazquez, Eva

    2018-01-01

    Anthropogenic plastic pollution is a global problem. In the marine environment, one of its less studied effects is the transport of attached biota, which might lead to introductions of non-native species in new areas or aid in habitat expansions of invasive species. The goal of the present work was to assess if the material composition of beached anthropogenic litter is indicative of the rafting fauna in a coastal area and could thus be used as a simple and cost-efficient tool for risk assessment in the future. Beached anthropogenic litter and attached biota along the 200 km coastline of Asturias, central Bay of Biscay, Spain, were analysed. The macrobiotic community attached to fouled litter items was identified using genetic barcoding combined with visual taxonomic analysis, and compared between hard plastics, foams, other plastics and non-plastic items. On the other hand, the material composition of beached litter was analysed in a standardized area on each beach. From these two datasets, the expected frequency of several rafting taxa was calculated for the coastal area and compared to the actually observed frequencies. The results showed that plastics were the most abundant type of beached litter. Litter accumulation was likely driven by coastal sources (industry, ports) and river/sewage inputs and transported by near-shore currents. Rafting vectors were almost exclusively made up of plastics and could mainly be attributed to fishing activity and leisure/ household. We identified a variety of rafting biota, including species of goose barnacles, acorn barnacles, bivalves, gastropods, polychaetes and bryozoan, and hydrozoan colonies attached to stranded litter. Several of these species were non-native and invasive, such as the giant Pacific oyster (Crassostrea gigas) and the Australian barnacle (Austrominius modestus). The composition of attached fauna varied strongly between litter items of different materials. Plastics, except for foam, had a much more diverse

  2. Anthropogenic marine litter composition in coastal areas may be a predictor of potentially invasive rafting fauna.

    PubMed

    Rech, Sabine; Borrell Pichs, Yaisel J; García-Vazquez, Eva

    2018-01-01

    Anthropogenic plastic pollution is a global problem. In the marine environment, one of its less studied effects is the transport of attached biota, which might lead to introductions of non-native species in new areas or aid in habitat expansions of invasive species. The goal of the present work was to assess if the material composition of beached anthropogenic litter is indicative of the rafting fauna in a coastal area and could thus be used as a simple and cost-efficient tool for risk assessment in the future. Beached anthropogenic litter and attached biota along the 200 km coastline of Asturias, central Bay of Biscay, Spain, were analysed. The macrobiotic community attached to fouled litter items was identified using genetic barcoding combined with visual taxonomic analysis, and compared between hard plastics, foams, other plastics and non-plastic items. On the other hand, the material composition of beached litter was analysed in a standardized area on each beach. From these two datasets, the expected frequency of several rafting taxa was calculated for the coastal area and compared to the actually observed frequencies. The results showed that plastics were the most abundant type of beached litter. Litter accumulation was likely driven by coastal sources (industry, ports) and river/sewage inputs and transported by near-shore currents. Rafting vectors were almost exclusively made up of plastics and could mainly be attributed to fishing activity and leisure/ household. We identified a variety of rafting biota, including species of goose barnacles, acorn barnacles, bivalves, gastropods, polychaetes and bryozoan, and hydrozoan colonies attached to stranded litter. Several of these species were non-native and invasive, such as the giant Pacific oyster (Crassostrea gigas) and the Australian barnacle (Austrominius modestus). The composition of attached fauna varied strongly between litter items of different materials. Plastics, except for foam, had a much more diverse

  3. Debris is not a cheese: litter in coastal Louisiana

    USGS Publications Warehouse

    Lindstedt, Dianne M.; Holmes, Joseph C.

    1989-01-01

    An 18-month study of six Louisiana beaches determined the extent, composition, and possible sources of beach litter. Data showed that from 2590 to 23,154 items may be encountered along any one-mile stretch of Louisiana beach, depending upon location and season, and that densities of litter ranged from 5 to 28 items per 100 m2. Plastics constituted 47% of the total, followed by polystyrene at 16% and glass at 10%. Drink-related items accounted for 40% of the identifiable material; operational wastes, 21%; galley wastes, 15%; personal items, 11%; and fishing items, 6%. Litter laws already exist at state and federal levels. Strict enforcement of Annex V of MARPOL should significantly reduce plastic beach litter. Solutions to beach litter will come from public participation in adopt-a-beach programs and statewide clean-ups and from educational programs focusing on existing laws, proper disposal methods, recycling, and the threat litter poses to wildlife and public health.

  4. C, N and P fertilization in an Amazonian rainforest supports stoichiometric dissimilarity as a driver of litter diversity effects on decomposition

    PubMed Central

    Barantal, Sandra; Schimann, Heidy; Fromin, Nathalie; Hättenschwiler, Stephan

    2014-01-01

    Plant leaf litter generally decomposes faster as a group of different species than when individual species decompose alone, but underlying mechanisms of these diversity effects remain poorly understood. Because resource C : N : P stoichiometry (i.e. the ratios of these key elements) exhibits strong control on consumers, we supposed that stoichiometric dissimilarity of litter mixtures (i.e. the divergence in C : N : P ratios among species) improves resource complementarity to decomposers leading to faster mixture decomposition. We tested this hypothesis with: (i) a wide range of leaf litter mixtures of neotropical tree species varying in C : N : P dissimilarity, and (ii) a nutrient addition experiment (C, N and P) to create stoichiometric similarity. Litter mixtures decomposed in the field using two different types of litterbags allowing or preventing access to soil fauna. Litter mixture mass loss was higher than expected from species decomposing singly, especially in presence of soil fauna. With fauna, synergistic litter mixture effects increased with increasing stoichiometric dissimilarity of litter mixtures and this positive relationship disappeared with fertilizer addition. Our results indicate that litter stoichiometric dissimilarity drives mixture effects via the nutritional requirements of soil fauna. Incorporating ecological stoichiometry in biodiversity research allows refinement of the underlying mechanisms of how changing biodiversity affects ecosystem functioning. PMID:25320173

  5. Microbial biomass and soil carbon after 8 and 9 years of field applications of alum-treated and untreated poultry litter and inorganic nitrogen

    USDA-ARS?s Scientific Manuscript database

    Amendment with aluminum sulfate (alum) is considered a best management practice for its benefits in poultry production and increased retention of nutrients in the litter. However, little is known about how long-term applications of alum-treated litter to soil will affect the microbial community and ...

  6. Litter decomposition across an air-pollution gradient in the San Bernardino Mountains

    Treesearch

    Mark E. Fenn; Paul H. Dunn

    1989-01-01

    Air pollution may affect forest ecosystems by altering nutrient cycling rates. The objective of this study was to compare decomposition rates of L-layer litter of ponderosa pine (Pinus ponderosa Laws.) and Jeffrey pine (Pinus jeffreyi Grev. & Balf,) collected from across an air-pollution gradient in the San Bernardino Mountains...

  7. Cellulolytic potential under environmental changes in microbial communities from grassland litter

    DOE PAGES

    Berlemont, Renaud; Allison, Steven D.; Weihe, Claudia; ...

    2014-11-25

    We report that in many ecosystems, global changes are likely to profoundly affect microorganisms. In Southern California, changes in precipitation and nitrogen deposition may influence the composition and functional potential of microbial communities and their resulting ability to degrade plant material. To test whether such environmental changes impact the distribution of functional groups involved in leaf litter degradation, we determined how the genomic diversity of microbial communities in a semi-arid grassland ecosystem changed under reduced precipitation or increased N deposition. We monitored communities seasonally over a period of 2 years to place environmental change responses into the context of naturalmore » variation. Fungal and bacterial communities displayed strong seasonal patterns, Fungi being mostly detected during the dry season whereas Bacteria were common during wet periods. Most putative cellulose degraders were associated with 33 bacterial genera and predicted to constitute 18% of the microbial community. Precipitation reduction reduced bacterial abundance and cellulolytic potential whereas nitrogen addition did not affect the cellulolytic potential of the microbial community. Finally, we detected a strong correlation between the frequencies of genera of putative cellulose degraders and cellulase genes. Thus, microbial taxonomic composition was predictive of cellulolytic potential. This work provides a framework for how environmental changes affect microorganisms responsible for plant litter deconstruction.« less

  8. A model of litter size distribution in cattle.

    PubMed

    Bennett, G L; Echternkamp, S E; Gregory, K E

    1998-07-01

    Genetic increases in twinning of cattle could result in increased frequency of triplet or higher-order births. There are no estimates of the incidence of triplets in populations with genetic levels of twinning over 40% because these populations either have not existed or have not been documented. A model of the distribution of litter size in cattle is proposed. Empirical estimates of ovulation rate distribution in sheep were combined with biological hypotheses about the fate of embryos in cattle. Two phases of embryo loss were hypothesized. The first phase is considered to be preimplantation. Losses in this phase occur independently (i.e., the loss of one embryo does not affect the loss of the remaining embryos). The second phase occurs after implantation. The loss of one embryo in this stage results in the loss of all embryos. Fewer than 5% triplet births are predicted when 50% of births are twins and triplets. Above 60% multiple births, increased triplets accounted for most of the increase in litter size. Predictions were compared with data from 5,142 calvings by 14 groups of heifers and cows with average litter sizes ranging from 1.14 to 1.36 calves. The predicted number of triplets was not significantly different (chi2 = 16.85, df = 14) from the observed number. The model also predicted differences in conception rates. A cow ovulating two ova was predicted to have the highest conception rate in a single breeding cycle. As mean ovulation rate increased, predicted conception to one breeding cycle increased. Conception to two or three breeding cycles decreased as mean ovulation increased because late-pregnancy failures increased. An alternative model of the fate of ova in cattle based on embryo and uterine competency predicts very similar proportions of singles, twins, and triplets but different conception rates. The proposed model of litter size distribution in cattle accurately predicts the proportion of triplets found in cattle with genetically high twinning

  9. Litter in submarine canyons off the west coast of Portugal

    NASA Astrophysics Data System (ADS)

    Mordecai, Gideon; Tyler, Paul A.; Masson, Douglas G.; Huvenne, Veerle A. I.

    2011-12-01

    Marine litter is of global concern and is present in all the world's oceans, including deep benthic habitats where the extent of the problem is still largely unknown. Litter abundance and composition were investigated using video footage and still images from 16 Remotely Operated Vehicle (ROV) dives in Lisbon, Setúbal, Cascais and Nazaré Canyons located west of Portugal. Litter was most abundant at sites closest to the coastline and population centres, suggesting the majority of the litter was land sourced. Plastic was the dominant type of debris, followed by fishing gear. Standardised mean abundance was 1100 litter items km -2, but was as high as 6600 litter items km -2 in canyons close to Lisbon. Although all anthropogenic material may be harmful to biota, debris was also used as a habitat by some macro-invertebrates. Litter composition and abundance observed in the canyons of the Portuguese margin were comparable to those seen in other deep sea areas around the world. Accumulation of litter in the deep sea is a consequence of human activities both on land and at sea. This needs to be taken into account in future policy decisions regarding marine pollution.

  10. Nonadditive effects of leaf litter species diversity on breakdown dynamics in a deteritus-bases stream

    Treesearch

    J.S. Kominoski; C.M. Pringle; B.A. Ball; M.A. Bradford; D.C. Coleman; D.B. Hall; M.D. Hunter

    2007-01-01

    Since species loss is predicted to be nonrandom, it is important to understand the manner in which those species that we anticipate losing interact with other species to affect ecosystem function. We tested whether litter species diversity, measured as richness and composition, affects breakdown dynamics in a detritus-based stream. Using full-factorial analyses of...

  11. Forest Floor Decomposition Following Hurricane Litter Inputs in Several Puerto Rican Forests

    Treesearch

    Rebecca Ostertag; Frederick N. Scatena; Whendee L. Silver

    2003-01-01

    Hurricanes affect ecosystem processes by altering resource availability and heterogeneity, but the spatial and temporal signatures of these events on biomass and nutrient cycling processes are not well understood. We examined mass and nutrient inputs of hurricane-derived litter in six tropical forests spanning three life zones in northeastern Puerto Rico after the...

  12. Fusarium equiseti LPSC 1166 and its in vitro role in the decay of Heterostachys ritteriana leaf litter.

    PubMed

    Franco, Ernesto; Troncozo, María I; Baez, Margot; Mirífico, María V; Robledo, Gerardo L; Balatti, Pedro A; Saparrat, Mario C N

    2018-03-01

    The role of microorganisms in litter degradation in arid and semi-arid zones, where soil and water salinization is one of the main factors limiting carbon turnover and decay, remains obscure. Heterostachys ritteriana (Amaranthaceae), a halophyte shrub growing in arid environments such as "Salinas Grandes" (Córdoba, Argentina), appears to be the main source of organic matter in the area. Little is known regarding the microorganisms associated with H. ritteriana, although they are a potential source of enzymes such as cellulolytic ones, which might be important in biotechnological fields such as bioethanol production using ionic liquids. In the present study, by studying the microbiota growing on H. ritteriana leaf litter in "Salinas Grandes," we isolated the cellulolytic fungus Fusarium equiseti LPSC 1166, which grew and degraded leaf litter under salt stress. The growth of this fungus was a function of the C substrate and the presence of NaCl. Although in vitro the fungus used both soluble and polymeric compounds from H. ritteriana litter and synthesized extracellular β-1,4 endoglucanases, its activity was reduced by 10% NaCl. Based on these results, F. equiseti LPSC 1166 can be described as a halotolerant cellulolytic fungus most probably playing a key role in the decay of H. ritteriana leaf litter in "Salinas Grandes."

  13. Effects of river flow regime on cottonwood leaf litter dynamics in semi-arid northwestern Colorado

    USGS Publications Warehouse

    Andersen, D.C.; Nelson, S.M.

    2003-01-01

    We compared production and breakdown of Fremont cottonwood (Populus deltoides wislizenii) leaf litter at matched floodplain sites on the regulated Green River and unregulated Yampa River in semi-arid northwestern Colorado. Litter production under trees was similar at sites in 1999 (250 g/m2, oven-dry) but lower in 2000 (215 and 130 g/m2), a drought year that also featured an outbreak of defoliating beetles at the Yampa River site. Our production values were similar to the few others reported for riparian forests within semi-arid or arid areas. Leaf litter in portions of the floodplain not inundated during the spring flood lost organic matter at the same rate as leaves placed in upland sites in 1998 and 2000: 35 to 50% of organic matter during an approximately 160-day spring and summer period. Inundated litter lost 55 to 90% of its organic matter during the same period. Organic matter loss from inundated leaves increased with duration of inundation and with deposition of fine sediment. Pooled across locations, leafpack data suggested that nitrogen concentration (mg N/kg organic matter) increased until about 65% of the initial organic matter was lost. This increase likely reflected the buildup of microbial decomposer populations. The role of insects and other macroinvertebrates in litter breakdown apparently was minor at both sites. Large spatial and temporal variation in litter dynamics in aridland floodplain settings is ensured by microtopographic variation in the alluvial surface coupled with year-to-year variation associated with most natural flood regimes. Factors reducing flood flow frequency or magnitude will reduce overall breakdown rates on the floodplain towards those found in drier upland environments.

  14. Dissolved organic carbon biodegradability from leaf litter leachates of riparian tropical trees

    NASA Astrophysics Data System (ADS)

    Bastianoni, A.; Montoya, J. V.; Mendez, C.; Paolini, J.

    2012-04-01

    among species. Based on the degree of DOC biodegradability, after 1d of incubation, all species could be grouped into three distinct categories (high, intermediate and low). Then, biodegradability of DOC declined steadily until reaching near-constant values at day 7 probably reflecting less availability of labile C compounds. Breakdown rates were not significantly correlated with DOC decay rates (r=-0.580, P =0.228, n=6). However when the remaining DOC and the remaining mass for all species was evaluated, a significant negative correlation was observed (r=-0.567, P =0.014, n=18) contradicting our initial hypothesis. Such results might be a consequence of the presence of secondary metabolites alongside labile DOC in some species leachates which could prevent microbial C consumption. Therefore, the quality of C released by leaching, measured as its biodegradability, does not seem to have a relationship with the amount of C lost by leaching. This could influence the C budget of the riparian ecosystem since the proportion of C consumed by stream microbes is affected by the chemical quality of leaf litter leachates.

  15. Crayfish Impact Desert River Ecosystem Function and Litter-Dwelling Invertebrate Communities through Association with Novel Detrital Resources

    PubMed Central

    Moody, Eric K.; Sabo, John L.

    2013-01-01

    Shifts in plant species distributions due to global change are increasing the availability of novel resources in a variety of ecosystems worldwide. In semiarid riparian areas, hydric pioneer tree species are being replaced by drought-tolerant plant species as water availability decreases. Additionally, introduced omnivorous crayfish, which feed upon primary producers, allochthonous detritus, and benthic invertebrates, can impact communities at multiple levels through both direct and indirect effects mediated by drought-tolerant plants. We tested the impact of both virile crayfish (Orconectes virilis) and litter type on benthic invertebrates and the effect of crayfish on detrital resources across a gradient of riparian vegetation drought-tolerance using field cages with leaf litter bags in the San Pedro River in Southeastern Arizona. Virile crayfish increased breakdown rate of novel drought-tolerant saltcedar (Tamarix ramosissima), but did not impact breakdown of drought-tolerant seepwillow (Baccharis salicifolia) or hydric Fremont cottonwood (Populus fremontii) and Gooding's willow (Salix goodingii). Effects on invertebrate diversity were observed at the litter bag scale, but no effects were found at the cage scale. Crayfish decreased alpha diversity of colonizing macroinvertebrates, but did not affect beta diversity. In contrast, the drought-tolerant litter treatment decreased beta diversity relative to hydric litter. As drought-tolerant species become more abundant in riparian zones, their litter will become a larger component of the organic matter budget of desert streams which may serve to homogenize the litter-dwelling community and support elevated populations of virile crayfish. Through impacts at multiple trophic levels, crayfish have a significant effect on desert stream ecosystems. PMID:23667600

  16. Broiler house litter sampling: the final frontier

    USDA-ARS?s Scientific Manuscript database

    Today, the sustainability of broiler operations reaches beyond the need for litter nutrient management plans that came to the forefront of the industry’s attention in the last fifteen years. Thorough characterization of litter within houses provides the basis for emission models to benefit growers,...

  17. How Autism Affects Speech Understanding in Multitalker Environments

    DTIC Science & Technology

    2015-12-01

    Page 1 AD_________________ Award Number: W81XWH-12-1-0363 TITLE: How Autism Affects Speech Understanding in Multitalker Environments PRINCIPAL...COVERED 30 Sep 2012 - 29 Sep 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER How Autism Affects Speech Understanding in Multitalker 5b. GRANT NUMBER...that adults with Autism Spectrum Disorders have particular difficulty recognizing speech in acoustically-hostile environments (e.g., Alcantara et al

  18. Influence of Soil Moisture on Litter Respiration in the Semiarid Loess Plateau

    PubMed Central

    Zhang, Yanjun; Guo, Shengli; Liu, Qingfang; Jiang, Jishao

    2014-01-01

    Understanding the response mechanisms of litter respiration to soil moisture in water-limited semi-arid regions is of vital importance to better understanding the interplay between ecological processes and the local carbon cycle. In situ soil respiration was monitored during 2010–2012 under various conditions (normal litter, no litter, and double litter treatments) in a 30-year-old artificial black locust plantation (Robinia pseudoacacia L.) on the Loess Plateau. Litter respiration with normal and double litter treatments exhibited similar seasonal variation, with the maximum value obtained in summer (0.57 and 1.51 μmol m−2 s−1 under normal and double litter conditions, respectively) and the minimum in spring (0.27 and 0.69 μmol m−2 s−1 under normal and double litter conditions, respectively). On average, annual cumulative litter respiration was 115 and 300 g C m−2 y−1 under normal and double litter conditions, respectively. Using a soil temperature of 17°C as the critical point, the relationship between litter respiration and soil moisture was found to follow quadratic functions well, whereas the determination coefficient was much greater at high soil temperature than at low soil temperature (33–35% vs. 22–24%). Litter respiration was significantly higher in 2010 and 2012 than in 2011 under both normal litter (132–165 g C m−2 y−1 vs. 48 g C m−2 y−1) and double litter (389–418 g C m−2 y−1 vs. 93 g C m−2 y−1) conditions. Such significant interannual variations were largely ascribed to the differences in summer rainfall. Our study demonstrates that, apart from soil temperature, moisture also has significant influence on litter respiration in semi-arid regions. PMID:25474633

  19. Data on litter quality of host grass plants with and without fungal endophytes

    PubMed Central

    Gundel, P.E.; Helander, M.; Garibaldi, L.A.; Vázquez-de-Aldana, B.R.; Zabalgogeazcoa, I.; Saikkonen, K.

    2016-01-01

    Certain Pooideae species form persistent symbiosis with fungal endophytes of Epichloë genus. Although endophytes are known to impact the ecology and evolution of host species, their effects on parameters related with quality of plant biomass has been elusive. This article provides information about parameters related with the quality of plant litter biomass of two important grass species (Schedonorus phoenix and Schedonorus pratensis) affected by the symbiosis with fungal endophytes (Epichloë coenophiala and Epichloë uncinata, respectively). Four population origins of S. phoenix and one of S. pratensis were included. Mineral, biochemical and structural parameters were obtained from three samples per factors combination [species (and population origin)×endophyte]. This data can be potentially used in other studies which, by means of ‘data reanalyzing’ or meta-analysis, attempt to find generalizations about endophyte effects on host plant litter biomass. The present data is associated with the research article “Role of foliar fungal endophytes on litter decomposition among species and population origins” (Gundel et al., In preparation) [1]. PMID:27182541

  20. Data on litter quality of host grass plants with and without fungal endophytes.

    PubMed

    Gundel, P E; Helander, M; Garibaldi, L A; Vázquez-de-Aldana, B R; Zabalgogeazcoa, I; Saikkonen, K

    2016-06-01

    Certain Pooideae species form persistent symbiosis with fungal endophytes of Epichloë genus. Although endophytes are known to impact the ecology and evolution of host species, their effects on parameters related with quality of plant biomass has been elusive. This article provides information about parameters related with the quality of plant litter biomass of two important grass species (Schedonorus phoenix and Schedonorus pratensis) affected by the symbiosis with fungal endophytes (Epichloë coenophiala and Epichloë uncinata, respectively). Four population origins of S. phoenix and one of S. pratensis were included. Mineral, biochemical and structural parameters were obtained from three samples per factors combination [species (and population origin)×endophyte]. This data can be potentially used in other studies which, by means of 'data reanalyzing' or meta-analysis, attempt to find generalizations about endophyte effects on host plant litter biomass. The present data is associated with the research article "Role of foliar fungal endophytes on litter decomposition among species and population origins" (Gundel et al., In preparation) [1].

  1. Litter survey detects the South Atlantic 'garbage patch'.

    PubMed

    Ryan, Peter G

    2014-02-15

    A distance-based technique was used to assess the distribution and abundance of floating marine debris (>1cm) in the southeast Atlantic Ocean between Cape Town and Tristan da Cunha, crossing the southern edge of the South Atlantic 'garbage patch' predicted by surface drift models. Most litter was made of plastic (97%). Detection distances were influenced by the size and buoyancy of litter items. Litter density decreased from coastal waters off Cape Town (>100 items km(-2)) to oceanic waters (<10 items km(-2)), and was consistently higher (6.2 ± 1.3 items km(-2)) from 3 to 8°E than in adjacent oceanic waters (2.7 ± 0.3 items km(-2)) or in the central South Atlantic around Tristan (1.0 ± 0.4 items km(-2)). The area with high litter density had few seaweeds, suggesting that most litter had been drifting for a long time. The results indicate that floating debris is accumulating in the South Atlantic gyre as far south as 34-35°S. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Dry-season ultraviolet radiation primes litter for wet season decomposition in a Mediterranean grassland

    NASA Astrophysics Data System (ADS)

    Baker, N. R.; Allison, S. D.

    2013-12-01

    Traditional decomposition models developed in mesic ecosystems often consistently underestimate rates of decomposition in more arid ecosystems such as deserts and Mediterranean grasslands. Photodegradation of plant litter by ultraviolet radiation (UV) is hypothesized to be one of the mechanisms accounting for the greater-than-expected rates of decomposition observed in these ecosystems. Putatively, photodegradation preferentially degrades complex aromatic compounds in litter such as lignin, whose decomposition is considered a rate-limiting step in the microbial decomposition of plant litter. This study tested the effects of attenuated ultraviolet radiation on the decomposition of two litter types over the course of a year in a Southern California Mediterranean grassland. The two types of litter differed primarily in lignin content to test for a differential effect of UV on high-lignin versus low-lignin litter. Rates of litter mass loss, changes in litter chemistry, and changes in microbial activity and microbial biomass were observed, and assays of extracellular enzymes were conducted at 5 points through the year, beginning during the dry season and continuing until the end of the following dry season. Litter exposed to attenuated ultraviolet radiation during the dry season had lower rates of mass loss than litter exposed to ambient radiation (6.1% vs. 8.6%, respectively, p < 0.04). Extracellular enzyme activities were significantly affected by UV attenuation, as low lignin samples exposed to attenuated UV displayed elevated cellulase enzyme activity potential during the wet season, while high lignin samples displayed decreased oxidative enzyme activity potential during the wet season. For example, potential activity of the cellulase cellobiohydrolase in low-lignin, ambient UV samples was 5286 μmol/hr*g during the wet season, compared to 7969 μmol/hr*g in attenuated UV samples (p < 0.003). Conversely, potential activity of the oxidative enzyme peroxidase in high

  3. C, N and P fertilization in an Amazonian rainforest supports stoichiometric dissimilarity as a driver of litter diversity effects on decomposition.

    PubMed

    Barantal, Sandra; Schimann, Heidy; Fromin, Nathalie; Hättenschwiler, Stephan

    2014-12-07

    Plant leaf litter generally decomposes faster as a group of different species than when individual species decompose alone, but underlying mechanisms of these diversity effects remain poorly understood. Because resource C : N : P stoichiometry (i.e. the ratios of these key elements) exhibits strong control on consumers, we supposed that stoichiometric dissimilarity of litter mixtures (i.e. the divergence in C : N : P ratios among species) improves resource complementarity to decomposers leading to faster mixture decomposition. We tested this hypothesis with: (i) a wide range of leaf litter mixtures of neotropical tree species varying in C : N : P dissimilarity, and (ii) a nutrient addition experiment (C, N and P) to create stoichiometric similarity. Litter mixtures decomposed in the field using two different types of litterbags allowing or preventing access to soil fauna. Litter mixture mass loss was higher than expected from species decomposing singly, especially in presence of soil fauna. With fauna, synergistic litter mixture effects increased with increasing stoichiometric dissimilarity of litter mixtures and this positive relationship disappeared with fertilizer addition. Our results indicate that litter stoichiometric dissimilarity drives mixture effects via the nutritional requirements of soil fauna. Incorporating ecological stoichiometry in biodiversity research allows refinement of the underlying mechanisms of how changing biodiversity affects ecosystem functioning. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  4. Conspecific Leaf Litter-Mediated Effect of Conspecific Adult Neighborhood on Early-Stage Seedling Survival in A Subtropical Forest

    PubMed Central

    Liu, Heming; Shen, Guochun; Ma, Zunping; Yang, Qingsong; Xia, Jianyang; Fang, Xiaofeng; Wang, Xihua

    2016-01-01

    Conspecific adults have strong negative effect on the survival of nearby early-stage seedlings and thus can promote species coexistence by providing space for the regeneration of heterospecifics. The leaf litter fall from the conspecific adults, and it could mediate this conspecific negative adult effect. However, field evidence for such effect of conspecific leaf litter remains absent. In this study, we used generalized linear mixed models to assess the effects of conspecific leaf litter on the early-stage seedling survival of four dominant species (Machilus leptophylla, Litsea elongate, Acer pubinerve and Distylium myricoides) in early-stage seedlings in a subtropical evergreen broad-leaved forest in eastern China. Our results consistently showed that the conspecific leaf litter of three species negatively affected the seedling survival. Meanwhile, the traditional conspecific adult neighborhood indices failed to detect this negative conspecific adult effect. Our study revealed that the accumulation of conspecific leaf litter around adults can largely reduce the survival rate of nearby seedlings. Ignoring it could result in underestimation of the importance of negative density dependence and negative species interactions in the natural forest communities. PMID:27886275

  5. OSPAR standard method and software for statistical analysis of beach litter data.

    PubMed

    Schulz, Marcus; van Loon, Willem; Fleet, David M; Baggelaar, Paul; van der Meulen, Eit

    2017-09-15

    The aim of this study is to develop standard statistical methods and software for the analysis of beach litter data. The optimal ensemble of statistical methods comprises the Mann-Kendall trend test, the Theil-Sen slope estimation, the Wilcoxon step trend test and basic descriptive statistics. The application of Litter Analyst, a tailor-made software for analysing the results of beach litter surveys, to OSPAR beach litter data from seven beaches bordering on the south-eastern North Sea, revealed 23 significant trends in the abundances of beach litter types for the period 2009-2014. Litter Analyst revealed a large variation in the abundance of litter types between beaches. To reduce the effects of spatial variation, trend analysis of beach litter data can most effectively be performed at the beach or national level. Spatial aggregation of beach litter data within a region is possible, but resulted in a considerable reduction in the number of significant trends. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. An alternative to antibiotic-based drugs in feed for enhancing performance of broilers grown on Eimeria spp.-infected litter.

    PubMed

    Stanley, V G; Gray, C; Daley, M; Krueger, W F; Sefton, A E

    2004-01-01

    Three trials were conducted to evaluate the effects of lasalocid, an anticoccidial feed additive (90.7 kg/ton); bacitracin, a growth-promoter (50 g/ton); and yeast culture residue (YCR) (1 kg/ton) on the performance of broiler chicks reared to 42 d of age on recycled litter. Recycled litter consisted of pine wood shavings containing droppings from chicks infected with 3 select strains of coccidia (Eimeria tenella, Eimeria maxima, and Eimeria acervulina). Response variables (BW, intestinal tract and litter coliform counts, cecal and liver relative weights, and litter moisture content) were recorded biweekly. Mean BW of chicks fed the diet supplemented with YCR was higher than that of the controls (P < 0.05) and comparable to that of the lasalocid-treated birds in all 3 trials. Mean BW of chicks in all treatment groups decreased uniformly as the litter aged and moisture content increased. The mean intestinal coliform population from YCR-treated chicks was lower (P < 0.05) than those of the control and lasalocid populations. The coliform count was consistently lower than that in chicks on a bacitracin-supplemented diet. Coliform counts from the control and lasalocid-treated birds did not differ. The litter coliform counts increased with increased use of the litter. Cecal and liver relative weights calculated from the chicks in trial 3 showed that only the liver was significantly affected by treatments. YCR appeared to be a viable alternative to bacitracin and lasalocid medication in enhancing growth of broiler chicks reared on recycled litter.

  7. Paroxetine exposure skews litter sex ratios in mice suggesting a Trivers–Willard process

    PubMed Central

    Gaukler, Shannon Marie; Ruff, James Steven; Potts, Wayne K.

    2016-01-01

    While conducting a toxicity assessment of the antidepressant paroxetine (Paxil®), in wild-derived mice (Mus musculus), we observed that exposed dams (P0) produced female biased litters (32:68 M:F). Though numerous experimental manipulations have induced sex ratio bias in mice, none have assessed the fitness of the offspring from these litters relative to controls. Here, we retrospectively analyze experimentally derived fitness data gathered for the purpose of toxicological assessment in light of 2 leading hypothesis (Trivers–Willard hypothesis [TWH] and cost of reproduction hypothesis [CRH]), seeking to test if this facultative sex ratio adjustment fits into an adaptive framework. Control F1 males were heavier than F1 females, but no differences in mass were detected between exposed F1 males and females, suggesting that exposed dams did not save energy by producing fewer males, despite producing 29.2% lighter litters relative to controls. F1 offspring of both treatments were released into seminatural enclosures where fitness was quantified. In enclosures, the relative reproductive success of F1-exposed males (compared with controls) was reduced by ~20% compared with the relative reproductive success of F1-exposed females. Thus, exposed dams increased their fitness by adjusting litters toward females who were less negatively affected by the exposure than males. Collectively, these data provide less support that the observed sex ratio bias results in energetic savings (CRH), and more support for the TWH because fitness was increased by biasing litters toward female offspring. These mammalian data are unique in their ability to support the TWH through the use of relevant fitness data. PMID:27418753

  8. Reducing highway litter.

    DOT National Transportation Integrated Search

    2013-06-01

    The objective of this report is to evaluate the status of highway litter in the State of Utah. Under the direction of Russ Scovil, engineer with the Utah Department of Transportation (UDOT), researchers at the University of Utah performed a literatur...

  9. Litter quality and its response to water level drawdown in boreal peatlands at plant species and community level

    NASA Astrophysics Data System (ADS)

    Straková, Petra; Anttila, Jani; Spetz, Peter; Kitunen, Veikko; Tapanila, Tarja; Laiho, Raija

    2010-05-01

    drawdown, compared to respective values of 394-658, 5.6-9.3, 0.22-24.4, 161-293 and 44-81 for the pristine conditions. The direct effects of WL drawdown on litter quality were overruled by the indirect effects via changes in vegetation composition. The short-term (reflecting transient conditions) and long-term (reflecting longer-lasting situation of already adapted ecosystem) effects were very different. Our results imply that the long-term effects will strongly affect the soil properties and C cycle of peatlands.

  10. Changes in soil carbon and nutrients following 6 years of litter removal and addition in a tropical semi-evergreen rain forest

    NASA Astrophysics Data System (ADS)

    Tanner, Edmund Vincent John; Sheldrake, Merlin W. A.; Turner, Benjamin L.

    2016-11-01

    Increasing atmospheric CO2 and temperature may increase forest productivity, including litterfall, but the consequences for soil organic matter remain poorly understood. To address this, we measured soil carbon and nutrient concentrations at nine depths to 2 m after 6 years of continuous litter removal and litter addition in a semi-evergreen rain forest in Panama. Soils in litter addition plots, compared to litter removal plots, had higher pH and contained greater concentrations of KCl-extractable nitrate (both to 30 cm); Mehlich-III extractable phosphorus and total carbon (both to 20 cm); total nitrogen (to 15 cm); Mehlich-III calcium (to 10 cm); and Mehlich-III magnesium and lower bulk density (both to 5 cm). In contrast, litter manipulation did not affect ammonium, manganese, potassium or zinc, and soils deeper than 30 cm did not differ for any nutrient. Comparison with previous analyses in the experiment indicates that the effect of litter manipulation on nutrient concentrations and the depth to which the effects are significant are increasing with time. To allow for changes in bulk density in calculation of changes in carbon stocks, we standardized total carbon and nitrogen on the basis of a constant mineral mass. For 200 kg m-2 of mineral soil (approximately the upper 20 cm of the profile) about 0.5 kg C m-2 was "missing" from the litter removal plots, with a similar amount accumulated in the litter addition plots. There was an additional 0.4 kg C m-2 extra in the litter standing crop of the litter addition plots compared to the control. This increase in carbon in surface soil and the litter standing crop can be interpreted as a potential partial mitigation of the effects of increasing CO2 concentrations in the atmosphere.

  11. [Effects of snow cover on water soluble and organic solvent soluble components during foliar litter decomposition in an alpine forest].

    PubMed

    Xu, Li-Ya; Yang, Wan-Qin; Li, Han; Ni, Xiang-Yin; He, Jie; Wu, Fu-Zhong

    2014-11-01

    Seasonal snow cover may change the characteristics of freezing, leaching and freeze-thaw cycles in the scenario of climate change, and then play important roles in the dynamics of water soluble and organic solvent soluble components during foliar litter decomposition in the alpine forest. Therefore, a field litterbag experiment was conducted in an alpine forest in western Sichuan, China. The foliar litterbags of typical tree species (birch, cypress, larch and fir) and shrub species (willow and azalea) were placed on the forest floor under different snow cover thickness (deep snow, medium snow, thin snow and no snow). The litterbags were sampled at snow formation stage, snow cover stage and snow melting stage in winter. The results showed that the content of water soluble components from six foliar litters decreased at snow formation stage and snow melting stage, but increased at snow cover stage as litter decomposition proceeded in the winter. Besides the content of organic solvent soluble components from azalea foliar litter increased at snow cover stage, the content of organic solvent soluble components from the other five foliar litters kept a continue decreasing tendency in the winter. Compared with the content of organic solvent soluble components, the content of water soluble components was affected more strongly by snow cover thickness, especially at snow formation stage and snow cover stage. Compared with the thicker snow covers, the thin snow cover promoted the decrease of water soluble component contents from willow and azalea foliar litter and restrain the decrease of water soluble component content from cypress foliar litter. Few changes in the content of water soluble components from birch, fir and larch foliar litter were observed under the different thicknesses of snow cover. The results suggested that the effects of snow cover on the contents of water soluble and organic solvent soluble components during litter decomposition would be controlled by

  12. Variations in bacterial communities during foliar litter decomposition in the winter and growing seasons in an alpine forest of the eastern Tibetan Plateau.

    PubMed

    Zhao, Yeyi; Wu, Fuzhong; Yang, Wanqin; Tan, Bo; He, Wei

    2016-01-01

    Bacterial communities are the primary engineers during litter decomposition and related material cycling, and they can be strongly controlled by seasonal changes in temperature and other environmental factors. However, limited information is available on changes in the bacterial community from winter to the growing season as litter decomposition proceeds in cold climates. Here, we investigated the abundance and structure of bacterial communities using real-time quantitative PCR and denaturing gradient gel electrophoresis (DGGE) during a 2-year field study of the decomposition of litter of 4 species in the winter and growing seasons of an alpine forest of the eastern Tibetan Plateau. The abundance of the bacterial 16S rRNA gene was relatively high during decomposition of cypress and birch litter in the first winter, but for the other litters 16S rRNA abundance during both winters was significantly lower than during the following growing season. A large number of bands were observed on the DGGE gels, and their intensities and number from the winter samples were lower than those from the growing season during the 2-year decomposition experiment. Eighty-nine sequences from the bands of bacteria that had been cut from the DGGE gels were affiliated with 10 distinct classes of bacteria and an unknown group. A redundancy analysis indicated that the moisture, mass loss, and elemental content (e.g., C, N, and P) of the litter significantly affected the bacterial communities. Collectively, the results suggest that uneven seasonal changes in climate regulate bacterial communities and other decomposers, thus affecting their contribution to litter decomposition processes in the alpine forest.

  13. Direct vs. Microclimate-Driven Effects of Tree Species Diversity on Litter Decomposition in Young Subtropical Forest Stands.

    PubMed

    Seidelmann, Katrin N; Scherer-Lorenzen, Michael; Niklaus, Pascal A

    2016-01-01

    Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2-3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of

  14. Direct vs. Microclimate-Driven Effects of Tree Species Diversity on Litter Decomposition in Young Subtropical Forest Stands

    PubMed Central

    Seidelmann, Katrin N.; Scherer-Lorenzen, Michael; Niklaus, Pascal A.

    2016-01-01

    Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2–3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of

  15. [Effects of grazing on the composition of soil animals and their decomposition function to Stipa grandis litter in Inner Mongolia typical steppe, China.

    PubMed

    Yang, Zhi Min; Hasitamier; Liu, Xin Min

    2016-09-01

    Grazing has been considered to be an important factor determining the composition of soil animals and decomposition of leaf litter in grassland ecosystem. Sampling plots were selected in ungrazed grassland, grazed grassland and sandy land. Litter bags were used to compare the changes of physicochemical properties of Stipa grandis litter and the composition of soil fauna in the process of the litter decomposition in Baiyinxile, Inner Mongolia, since 2010 to 2012. A total number of 67056 soil animals were captured, belonging to five phyla and eight classes, including 23 families of mites and 19 families of insects. After 780 days' decomposition, the loss of the organic matter of S. grandis litter was from 92.5% to 40.0% in the ungrazed grassland, and to 41.3% in the grazed grassland, with no significant difference observed. However, there was a significant difference (P<0.05) between the ratio of litter residues of the ungrazed grassland (50.0%) and that of the grazed grassland (23.0%). The abundance of soil animals in the residual litters was significantly decreased in the grazed grassland compared to the ungrazed grassland. When the litter was moved into the sandy land, the decomposition rate of organic matter in the residual litter was not significant changed but the ratio of litter residue declined significantly, and the composition of mite community in the resi-dual litter changed significantly. Our results illustrated that grazing activity could affect the composition and abundance of soil fauna in temperate grassland, but slightly influenced the decomposition of organic matter. Therefore, soil animals had relatively weak direct effects on the decomposition of litter in this semi-arid region.

  16. Species-Specific Effects of Woody Litter on Seedling Emergence and Growth of Herbaceous Plants

    PubMed Central

    Koorem, Kadri; Price, Jodi N.; Moora, Mari

    2011-01-01

    The effect of litter on seedling establishment can influence species richness in plant communities. The effect of litter depends on amount, and also on litter type, but relatively little is known about the species-specific effects of litter. We conducted a factorial greenhouse experiment to examine the effect of litter type, using two woody species that commonly co-occur in boreonemoral forest—evergreen spruce (Picea abies), deciduous hazel (Corylus avellana), and a mixture of the two species—and litter amount—shallow (4 mm), deep (12 mm) and leachate—on seedling emergence and biomass of three understorey species. The effect of litter amount on seedling emergence was highly dependent on litter type; while spruce needle litter had a significant negative effect that increased with depth, seedling emergence in the presence of hazel broadleaf litter did not differ from control pots containing no litter. Mixed litter of both species also had a negative effect on seedling emergence that was intermediate compared to the single-species treatments. Spruce litter had a marginally positive (shallow) or neutral effect (deep) on seedling biomass, while hazel and mixed litter treatments had significant positive effects on biomass that increased with depth. We found non-additive effects of litter mixtures on seedling biomass indicating that high quality hazel litter can reduce the negative effects of spruce. Hazel litter does not inhibit seedling emergence; it increases seedling growth, and creates better conditions for seedling growth in mixtures by reducing the suppressive effect of spruce litter, having a positive effect on understorey species richness. PMID:22028890

  17. Phosphorus runoff losses from subsurface-applied poultry litter on coastal plain soils.

    PubMed

    Kibet, Leonard C; Allen, Arthur L; Kleinman, Peter J A; Feyereisen, Gary W; Church, Clinton; Saporito, Lou S; Way, Thomas R

    2011-01-01

    The application of poultry litter to soils is a water quality concern on the Delmarva Peninsula, as runoff contributes P to the eutrophic Chesapeake Bay. This study compared a new subsurface applicator for poultry litter with conventional surface application and tillage incorporation of litter on a Coastal Plain soil under no-till management. Monolith lysimeters (61 cm by 61 cm by 61 cm) were collected immediately after litter application and subjected to rainfall simulation (61 mm h(-1) 1 h) 15 and 42 d later. In the first rainfall event, subsurface application of litter significantly lowered total P losses in runoff (1.90 kg ha(-1)) compared with surface application (4.78 kg ha(-1)). Losses of P with subsurface application were not significantly different from disked litter or an unamended control. By the second event, total P losses did not differ significantly between surface and subsurface litter treatments but were at least twofold greater than losses from the disked and control treatments. A rising water table in the second event likely mobilized dissolved forms of P in subsurface-applied litter to the soil surface, enriching runoff water with P. Across both events, subsurface application of litter did not significantly decrease cumulative losses of P relative to surface-applied litter, whereas disking the litter into the soil did. Results confirm the short-term reduction of runoff P losses with subsurface litter application observed elsewhere but highlight the modifying effect of soil hydrology on this technology's ability to minimize P loss in runoff.

  18. Quality of poultry litter-derived granular activated carbon.

    PubMed

    Qiu, Guannan; Guo, Mingxin

    2010-01-01

    Utilization of poultry litter as a source material for generating activated carbon is a value-added and environmentally beneficial approach to recycling organic waste. In this study, the overall quality of poultry litter-derived granular activated carbon was systematically evaluated based on its various physical and chemical properties. Granular activated carbon generated from pelletized poultry litter following a typical steam-activation procedure possessed numerous micropores in the matrix. The product exhibited a mean particle diameter of 2.59 mm, an apparent density of 0.45 g cm(-3), a ball-pan hardness of 91.0, an iodine number of 454 mg g(-1), and a BET surface area of 403 m(2) g(-1). It contained high ash, nitrogen, phosphorus contents and the trace elements Cu, Zn, and As. Most of the nutrients and toxic elements were solidified and solution-unextractable. In general, poultry litter-based activated carbon demonstrated overall quality comparable to that of low-grade commercial activated carbon derived from coconut shell and bituminous coal. It is promising to use poultry litter as a feedstock to manufacture activated carbon for wastewater treatment.

  19. Emissions of volatile organic compounds during the decomposition of plant litter

    NASA Astrophysics Data System (ADS)

    Gray, Christopher M.; Monson, Russell K.; Fierer, Noah

    2010-09-01

    Volatile organic compounds (VOCs) are emitted during plant litter decomposition, and such VOCs can have wide-ranging impacts on atmospheric chemistry, terrestrial biogeochemistry, and soil ecology. However, we currently have a limited understanding of the relative importance of biotic versus abiotic sources of these VOCs and whether distinct types of litter emit different types and quantities of VOCs during decomposition. We analyzed VOCs emitted by microbes or by abiotic mechanisms during the decomposition of litter from 12 plant species in a laboratory experiment using proton transfer reaction mass spectrometry (PTR-MS). Net emissions from litter with active microbial populations (non-sterile litters) were between 0 and 11 times higher than emissions from sterile controls over a 20-d incubation period, suggesting that abiotic sources of VOCs are generally less important than biotic sources. In all cases, the sterile and non-sterile litter treatments emitted different types of VOCs, with methanol being the dominant VOC emitted from litters during microbial decomposition, accounting for 78 to 99% of the net emissions. We also found that the types of VOCs released during biotic decomposition differed in a predictable manner among litter types with VOC profiles also changing as decomposition progressed over time. These results show the importance of incorporating both the biotic decomposition of litter and the species-dependent differences in terrestrial vegetation into global VOC emission models.

  20. Litter decomposition rate and soil organic matter quality in a patchwork heathland of Southern Norway

    NASA Astrophysics Data System (ADS)

    Certini, G.; Vestgarden, L. S.; Forte, C.; Tau Strand, L.

    2014-07-01

    Norwegian heathland soils, although scant and shallow, are major reservoirs of carbon (C). We aimed at assessing whether vegetation cover and, indirectly, its driving factor soil drainage are good proxies for soil organic matter (SOM) composition and dynamics in a typical heathland area of Southern Norway consisting in a patchwork of three different types of vegetation, dominated by Calluna, Molinia, or Sphagnum. Such vegetation covers were clearly associated to microtopographic differences, which in turn dictated differences in soil moisture regime, Calluna growing in the driest sites, Sphagnum in the wettest, and Molinia in sites with intermediate moisture. Litter decomposition was followed over a period of 1 year, by placing litterbags filled with biomass from each dominant species under each type of vegetation cover. The composition of the living biomass, the bulk SOM and some extractable fractions of SOM were investigated by chemical methods and solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Litter decomposition was faster for Molinia and Calluna, irrespective of the vegetation cover of the site where they were placed. Sphagnum litter decomposed very slowly, especially under Calluna, where the soil environment is by far more oxidising than under itself. In terms of SOM quality, Calluna covered areas showed the greatest differences from the others, in particular a much higher contribution from lipids and aliphatic biopolymers, apparently related to biomass composition. Our findings showed that in the studied environment litter decomposition rate and SOM composition are actually dependent on vegetation cover and/or soil drainage. On this basis, monitoring changes in the patchwork of vegetation types in boreal heathlands could be a reliable cost-effective way to account for modifications in the SOM potential to last induced by climate change.

  1. Relationship of cryptorchidism with sex ratios and litter sizes in 12 dog breeds.

    PubMed

    Gubbels, Ed J; Scholten, Janneke; Janss, Luc; Rothuizen, Jan

    2009-07-01

    The aim of this study was to identify the influence of genetic carriership for cryptorchidism on litter sizes and sex ratios in the offspring. Weaning data of 11,230 litters in 12 purebred dog breeds were evaluated. Parents were classified as cryptorchidism 'carriers' (C) when at least one of their offspring was found cryptorchid. Subsequently the effects of 'carrier' and 'non-carrier' (NC) parents on their litters were studied. In litters from C x C parents we found an increased number of males per litter in all breeds, a reduced number of females per litter in 8 breeds and an increased litter size in 11 breeds in comparison with litters from NC x NC parents. Over all breeds the effects on litter size, on number of males per litter and on sex ratio were highly significant. Mixed litters from C x NC and NC x C did not show these effects and were not significantly different from the NC x NC offspring. Our results suggest a general mechanism in the dog species which causes cryptorchidism as well as increased male/female ratios and increased litter sizes. A consequence of such a mechanism is that selection in favor of increasing reproduction output frustrates selective efforts to eliminate cryptorchidism.

  2. Nitrogen availability in composted poultry litter using natural amendments.

    PubMed

    Turan, N Gamze

    2009-02-01

    Poultry litter compost is used as fertilizer on agricultural land because of its high nutrient content. A major limitation of land application of poultry litter compost is the loss of nitrogen via NH3 volatilization. The present work was conducted to monitor nitrogen availability during composting of poultry litter with natural zeolite, expanded perlite, pumice and expanded vermiculite. Poultry litter was composted for 100 days using five in-vessel composting simulators with a volumetric ratio of natural materials:poultry litter of 1:10. It was found that natural materials significantly reduced NH3 volatilization. At the end of the process, the control treatment without any natural materials had the lowest rate of total N: 72% of the initial total N was lost from the compost made with no amendment, while 53, 42, 26 and 16% of initial total N was lost from compost containing expandable perlite, expandable vermiculite, pumice and natural zeolite, respectively.

  3. Effectiveness of Naturally Occurring Substances Added to Duck Litter in Reducing Emergence and Landing of Adult Musca domestica (Diptera: Muscidae).

    PubMed

    Lachance, Simon; Shiell, Justine; Guerin, Michele T; Scott-Dupree, Cynthia

    2017-02-01

    Poultry barns provide an ideal breeding environment for Musca domestica L. (Diptera: Muscidae) owing to the controlled temperatures and litter (manure plus bedding material) accumulation. Management techniques that render the litter less suitable for immature stage development, such as the addition of naturally occurring insecticidal substances, could reduce fly infestations. The effectiveness of acetic, boric, and citric acids; diatomaceous earth; and hydrated lime at restricting female landing and growth of house flies in duck litter was evaluated. Litter treated with 1.9% and 4.7% by weight of acetic or boric acid had significantly lower adult emergence rates compared with the same concentrations of citric acid, diatomaceous earth, hydrated lime, or the untreated control litter. The pH of duck litter treated with acetic or citric acid was significantly reduced and remained significantly lower than the control litter (pH 8.7) for 10 d. Significantly more house flies landed on a house fly-rearing substrate (wheat bran, powdered milk, bloodmeal, water, and yeast) than litter treated with any of the other test substances or the control. The LC50 for boric acid was estimated to be 0.01% by weight, which was lower than that of acetic acid (1.42%). Similarly, the LC90 of boric acid was estimated to be 0.12%, which was lower than that of acetic acid (10.03%). Acetic acid and boric acid have the potential to be incorporated into litter as a pest management tactic to reduce house fly populations in duck production facilities. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Short-term Dynamics of Photopriming Increase Carbon Loss During Litter Decomposition

    NASA Astrophysics Data System (ADS)

    Lin, Y.; King, J. Y.; Karlen, S. D.; Ralph, J.

    2017-12-01

    Solar radiation plays a key role in carbon (C) cycling by increasing the decomposition rates of plant litter through photodegradation. This process is particularly important in drylands where solar radiation is high and microbial activity may be limited by water availability. One mechanism of photodegradation may be the facilitation of microbial decomposition of litter by altering litter chemistry and consequently degradability, termed photopriming. However, it remains unclear to what extent photopriming contributes to litter decomposition. We evaluated photopriming by ultraviolet (UV) radiation through two laboratory experiments. In one experiment, we found that four months of UV exposure increased mass loss by 3-4% compared to dark treatment in two of three litter species commonly found in California oak savanna; however, UV exposure did not alter litter degradability as measured by microbial respiration in an incubation study. UV exposure had limited effects on lignin and other cell wall structures, but one month of microbial decomposition in the dark significantly reduced lignin β-aryl ether inter-unit linkages and acetylated xylans, which interestingly was the same pattern seen in litter exposed to UV radiation under field conditions and may account for the significant effects of UV exposure on litter mass loss observed in situ. These results indicate that microbial decomposition, not abiotic photodegradation, was ultimately responsible for changes in litter chemistry observed in the field. In a separate experiment, litter of a common grass was incubated for 128 days under either alternating UV radiation and dark conditions at two-day intervals or continuous darkness. During the second half of the experiment, alternating UV exposure increased CO2 production by 35% compared to continuous darkness, suggesting that UV exposure induces subtle but important changes in litter chemistry that facilitate microbial decomposition on a temporal scale of days. Together

  5. Greenhouse gas and ammonia emission from a litter-windrowing in bird houses

    USDA-ARS?s Scientific Manuscript database

    One of emerging poultry manure management practices is in house windrowing to disinfect the litter. With this practice, growers windrow the litter in broiler houses between flocks, usually for 2 weeks. This results in high litter temperatures that can reduce pathogens in the litter. However, this p...

  6. Ammonia and nitrous oxide emissions from broiler houses with downtime windrowed litter

    USDA-ARS?s Scientific Manuscript database

    An emerging poultry manure management practice is in house windrowing to disinfect the litter. With this practice, growers windrow the litter in broiler houses between flocks, usually for 2 weeks. This results in high litter temperatures that can reduce pathogens in the litter. However, this practi...

  7. Poultry litter placement effects on cotton seedling emergence and early growth stage

    USDA-ARS?s Scientific Manuscript database

    Interest in using poultry litter (PL) as a nutrient source for row crop production has increased in the Southeastern U.S. Poultry litter is generally broadcasted on the soil surface. This practice exposes litter N to volatilization and litter P to loss with surface water runoff, which potentially ne...

  8. Soil and litter exchange of reactive trace gases

    EPA Science Inventory

    The soil and litter play an important role in the exchange of trace gases between terrestrial ecosystems and the atmosphere. - The exchange of ammonia between vegetation and the atmosphere is highly influenced by soil and litter emissions especially in managed ecosystems (grassla...

  9. Separating duff and litter for improved mass and carbon estimates

    Treesearch

    David Chojnacky; Michael Amacher; Michael Gavazzi

    2009-01-01

    Mass and carbon load estimates, such as those from forest soil organic matter (duff and litter), inform forestry decisions. The US Forest Inventory and Analysis (FIA) Program systematically collects data nationwide: a down woody material protocol specifies discrete duff and litter depth measurements, and a soils protocol specifies mass and carbon of duff and litter...

  10. Marine litter on the floor of deep submarine canyons of the Northwestern Mediterranean Sea: The role of hydrodynamic processes

    NASA Astrophysics Data System (ADS)

    Tubau, Xavier; Canals, Miquel; Lastras, Galderic; Rayo, Xavier; Rivera, Jesus; Amblas, David

    2015-05-01

    Marine litter represents a widespread type of pollution in the World's Oceans. This study is based on direct observation of the seafloor by means of Remotely Operated Vehicle (ROV) dives and reports litter abundance, type and distribution in three large submarine canyons of the NW Mediterranean Sea, namely Cap de Creus, La Fonera and Blanes canyons. Our ultimate objective is establishing the links between active hydrodynamic processes and litter distribution, thus going beyond previous, essentially descriptive studies. Litter was monitored using the Liropus 2000 ROV. Litter items were identified in 24 of the 26 dives carried out in the study area, at depths ranging from 140 to 1731 m. Relative abundance of litter objects by type, size and apparent weight, and distribution of litter in relation to depth and canyon environments (i.e. floor and flanks) were analysed. Plastics are the dominant litter component (72%), followed by lost fishing gear, disregarding their composition (17%), and metal objects (8%). Most of the observed litter seems to be land-sourced. It reaches the ocean through wind transport, river discharge and after direct dumping along the coastline. While coastal towns and industrial areas represent a permanent source of litter, tourism and associated activities relevantly increase litter production during summer months ready to be transported to the deep sea by extreme events. After being lost, fishing gear such as nets and long-lines has the potential of being harmful for marine life (e.g. by ghost fishing), at least for some time, but also provides shelter and a substrate on which some species like cold-water corals are capable to settle and grow. La Fonera and Cap de Creus canyons show the highest mean concentrations of litter ever seen on the deep-sea floor, with 15,057 and 8090 items km-2, respectively, and for a single dive litter observed reached 167,540 items km-2. While most of the largest concentrations were found on the canyon floors at

  11. Can persuasive and demonstrative messages to visitors reduce littering in river beaches?

    PubMed

    Cingolani, Ana M; Barberá, Iván; Renison, Daniel; Barri, Fernando R

    2016-12-01

    Littering of public areas is a significant problem worldwide. Here we evaluate the success of persuasive and demonstrative messages at reducing littering in highly visited river beaches in Argentina. We made an intervention at the beaches which consisted of a personalized verbal request asking visitors to take their litter to the waste cans (persuasive message) while they were exposed to the example of picking up the litter already left on the beach (demonstrative message). We conducted 102 observations distributed over 29 dates, two years and four beaches. Each observation consisted of three or four rounds: before the presence of visitors we cleaned the beaches, during the stay of visitors we made the intervention (once or twice) in two out of the four beaches, and early next morning we estimated the amount of litter left per beach. Litter weight ranged from 0 to 53gvisitor -1 day -1 . Littering per visitor was reduced an average of 35% due to the intervention (p=0.049). We also found differences among beaches (p=0.001), and an increase in littering with crowding (p=0.005). We show for the first time that the personalized request combined with the example of picking up litter is effective in reducing littering in a Latin American country. Copyright © 2016. Published by Elsevier Ltd.

  12. Application of composted poultry litter as a fertilizer for landscape bedding plants

    USDA-ARS?s Scientific Manuscript database

    Each year, over 16 million tons of poultry litter is produced in the U.S. Federal and state regulations now limit the amount of poultry litter that can be land-applied, making it difficult to store and dispose poultry litter. The objective of this study was to evaluate composted poultry litter (CPL)...

  13. Efficiency of basalt zeolite and Cuban zeolite to adsorb ammonia released from poultry litter.

    PubMed

    Nuernberg, Giselle B; Moreira, Marcelo A; Ernani, Paulo R; Almeida, Jaime A; Maciel, Tais M

    2016-12-01

    Confined poultry production is an important livestock activity, which generates large amounts of waste associated with the potential for environmental pollution and ammonia (NH 3 ) emissions. The release of ammonia negatively affects poultry production and decreases the N content of wastes that could be used as soil fertilizers. The objective of this study was to evaluate a low-cost, simple and rapid method to simulate ammonia emissions from poultry litter as well as to quantify the reduction in the ammonia emissions to the environment employing two adsorbent zeolites, a commercial Cuban zeolite (CZ) and a ground basalt Brazilian rock containing zeolite (BZ). The experiments were conducted in a laboratory, in 2012-2013. The zeolites were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), physical adsorption of N 2 (BET) and scanning electron microscopy (SEM). Ammonia released from poultry litter and its simulation from NH 4 OH solution presented similar capture rates of 7.99 × 10 -5 and 7.35 × 10 -5  mg/h, respectively. Both zeolites contain SiO 2 and Al 2 O 3 as major constituents, with contents of 84% and 12% in the CZ, and 51% and 12% in the BZ, respectively, besides heulandite groups. Their BET surface areas were 89.4 and 11.3 m 2  g -1 , respectively, and the two zeolites had similar surface morphologies. The zeolites successfully adsorbed the ammonia released, but CZ was more efficient than BZ, since to capture all of the ammonia 5 g of CZ and 20 g of BZ were required. This difference is due to higher values for the superficial area, porosity, CEC and acid site strength of CZ relatively to BZ. The proposed methodology was shown to be an efficient method to simulate and quantify the ammonia released from poultry litter. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Allelopathy of Bracken Fern (Pteridium arachnoideum): New Evidence from Green Fronds, Litter, and Soil

    PubMed Central

    Juliano Gualtieri, Sonia Cristina; Rodrigues-Filho, Edson; Macías, Francisco Antonio

    2016-01-01

    The neotropical bracken fern Pteridium arachnoideum (Kaulf.) Maxon. (Dennstaedtiaceae) is described as an aggressive pioneer plant species. It invades abandoned or newly burned areas and represents a management challenge at these invaded sites. Native to the Atlantic Forest and Cerrado (Tropical Savanna) Brazilian biomes, P. arachnoideum has nevertheless become very problematic in these conservation hotspots. Despite some reports suggesting a possible role of allelopathy in this plant’s dominance, until now there has been little evidence of isolated and individually identified compounds with phytotoxic activities present in its tissues or in the surrounding environment. Thus, the aim of this study was to investigate the allelopathic potential of P. arachnoideum by isolating and identifying any secondary metabolites with phytotoxic activity in its tissues, litter, and soil. Bioguided phytochemical investigation led to the isolation and identification of the proanthocyanidin selligueain A as the major secondary compound in the green fronds and litter of this fern. It is produced by P. arachnoideum in its green fronds, remains unaltered during the senescence process, and is the major secondary compound present in litter. Selligueain A showed phytotoxic activity against the selected target species sesame (Sesamum indicum) early development. In particular, the compound inhibited root and stem growth, and root metaxylem cell size but did not affect chlorophyll content. This compound can be considered as an allelochemical because it is present in the soil under P. arachnoideum patches as one of the major compounds in the soil solution. This is the first report of the presence of selligueain A in any member of the Dennstaedtiaceae family and the first time an isolated and identified allelochemical produced by members of the Pteridium species complex has been described. This evidence of selligueain A as a putative allelochemical of P. arachnoideum reinforces the role of

  15. Differentiating littering, urban runoff and marine transport as sources of marine debris in coastal and estuarine environments

    PubMed Central

    Willis, Kathryn; Denise Hardesty, Britta; Kriwoken, Lorne; Wilcox, Chris

    2017-01-01

    Marine debris is a burgeoning global issue with economic, ecological and aesthetic impacts. While there are many studies now addressing this topic, the influence of urbanisation factors such as local population density, stormwater drains and roads on the distribution of coastal litter remains poorly understood. To address this knowledge gap, we carried out standardized surveys at 224 transect surveys at 67 sites in two estuaries and along the open coast in Tasmania, Australia. We explored the relative support for three hypotheses regarding the sources of the debris; direct deposition by beachgoers, transport from surrounding areas via storm water drains and coastal runoff, and onshore transport from the marine system. We found strong support for all three mechanisms, however, onshore transport from the marine reservoir was the most important mechanism. Overall, the three models together explained 45.8 percent of the variation in our observations. Our results also suggest that most debris released into the marine environment is deposited locally, which may be the answer to where all the missing plastic is in the ocean. Furthermore, local interventions are likely to be most effective in reducing land-based inputs into the ocean. PMID:28281667

  16. Differentiating littering, urban runoff and marine transport as sources of marine debris in coastal and estuarine environments

    NASA Astrophysics Data System (ADS)

    Willis, Kathryn; Denise Hardesty, Britta; Kriwoken, Lorne; Wilcox, Chris

    2017-03-01

    Marine debris is a burgeoning global issue with economic, ecological and aesthetic impacts. While there are many studies now addressing this topic, the influence of urbanisation factors such as local population density, stormwater drains and roads on the distribution of coastal litter remains poorly understood. To address this knowledge gap, we carried out standardized surveys at 224 transect surveys at 67 sites in two estuaries and along the open coast in Tasmania, Australia. We explored the relative support for three hypotheses regarding the sources of the debris; direct deposition by beachgoers, transport from surrounding areas via storm water drains and coastal runoff, and onshore transport from the marine system. We found strong support for all three mechanisms, however, onshore transport from the marine reservoir was the most important mechanism. Overall, the three models together explained 45.8 percent of the variation in our observations. Our results also suggest that most debris released into the marine environment is deposited locally, which may be the answer to where all the missing plastic is in the ocean. Furthermore, local interventions are likely to be most effective in reducing land-based inputs into the ocean.

  17. Effects of Enrichment and Litter Parity on Reproductive Performance and Behavior in BALB/c and 129/Sv Mice.

    PubMed

    Whitaker, Julia W; Moy, Sheryl S; Pritchett-Corning, Kathleen R; Fletcher, Craig A

    2016-01-01

    We examined the effect of adding species-appropriate environmental enrichment items to breeding cages of BALB/cAnNCrl and 129S2/SvPasCrl mice. The 3 enrichment conditions were: 1) cotton nesting material; 2) nesting material plus a paper shelter and rolled paper bedding; and 3) an igloo dome with an exercise wheel in addition to the shelter-group enrichments. We measured litter size, litter survival to weaning age, average pup weight at 21 d, and the interlitter interval to evaluate reproductive performance. A random subset of the first- or second-litter offspring from each enrichment condition and strain was assessed in multiple behavioral tests. Enrichment significantly affected anxiety-like behavior and sociability, with the direction of change dependent on strain and sex. Litter parity had greater effects on some reproductive parameters than did the enrichment condition, and this effect was not solely due to a difference between the first compared with subsequent litters. The significant effects of litter parity on the number of pups born and weaned, female pup weight, and interlitter interval were dependent on the enrichment condition in BALB/c but not 129/Sv mice. Offspring from the first or second litter were included in a generational component to investigate whether enrichment effects on reproduction persist in adult offspring after transfer to a different facility for breeding. Natal cage enrichment had no effect on any reproductive parameter in the transferred mice. Overall, additional enrichment beyond nesting material had a beneficial effect on the interlitter interval in BALB/c mice and on the number of pups weaned in 129/Sv mice.

  18. Effects of Enrichment and Litter Parity on Reproductive Performance and Behavior in BALB/c and 129/Sv Mice

    PubMed Central

    Whitaker, Julia W; Moy, Sheryl S; Pritchett-Corning, Kathleen R; Fletcher, Craig A

    2016-01-01

    We examined the effect of adding species-appropriate environmental enrichment items to breeding cages of BALB/cAnNCrl and 129S2/SvPasCrl mice. The 3 enrichment conditions were: 1) cotton nesting material; 2) nesting material plus a paper shelter and rolled paper bedding; and 3) an igloo dome with an exercise wheel in addition to the shelter-group enrichments. We measured litter size, litter survival to weaning age, average pup weight at 21 d, and the interlitter interval to evaluate reproductive performance. A random subset of the first- or second-litter offspring from each enrichment condition and strain was assessed in multiple behavioral tests. Enrichment significantly affected anxiety-like behavior and sociability, with the direction of change dependent on strain and sex. Litter parity had greater effects on some reproductive parameters than did the enrichment condition, and this effect was not solely due to a difference between the first compared with subsequent litters. The significant effects of litter parity on the number of pups born and weaned, female pup weight, and interlitter interval were dependent on the enrichment condition in BALB/c but not 129/Sv mice. Offspring from the first or second litter were included in a generational component to investigate whether enrichment effects on reproduction persist in adult offspring after transfer to a different facility for breeding. Natal cage enrichment had no effect on any reproductive parameter in the transferred mice. Overall, additional enrichment beyond nesting material had a beneficial effect on the interlitter interval in BALB/c mice and on the number of pups weaned in 129/Sv mice. PMID:27423144

  19. Influence of different litter materials on cecal microbiota colonization in broiler chickens.

    PubMed

    Torok, V A; Hughes, R J; Ophel-Keller, K; Ali, M; Macalpine, R

    2009-12-01

    A chicken growth study was conducted to determine if litter type influenced gut microbiota and performance in broilers. Seven bedding materials were investigated and included soft and hardwood sawdust, softwood shavings, shredded paper, chopped straw, rice hulls, and reused softwood shavings. Microbial profiling was done to investigate changes in cecal bacterial communities associated with litter material and age. Cecal microbiota were investigated at 14 and 28 d of age (n = 12 birds/litter material). At both ages, the cecal microbiota of chickens raised on reused litter was significantly (P < 0.05) different from that of chickens raised on any of the other litter materials, except softwood shavings at d 28. Cecal microbiota was also significantly different between birds raised on shredded paper and rice hulls at both ages. Age had a significant influence on cecal microbiota composition regardless of litter material. Similarity in cecal microbial communities among birds raised on the same litter treatment was greater at 28 d of age (29 to 40%) than at 14 d of age (25 to 32%). Bird performance on the different litter materials was measured by feed conversion ratio, live weight, and feed intake. Significant (P < 0.05) differences were detected in live weight at 14 d of age and feed intake at 14 and 28 d of age among birds (n = 160/treatment) raised on some of the different litter materials. However, no significant (P > 0.05) differences were observed in feed conversion ratio among birds raised on any of the 7 different litter materials at either 14 or 28 d of age. The type of litter material can influence colonization and development of cecal microbiota in chickens. Litter-induced changes in the gut microbiota may be partially responsible for some of the significant differences observed in early rates of growth; therefore, litter choice may have an important role in poultry gut health particularly in the absence of in-feed antibiotics.

  20. Enhanced solid waste management by understanding the effects of gender, income, marital status, and religious convictions on attitudes and practices related to street littering in Nablus - Palestinian territory.

    PubMed

    Al-Khatib, Issam A; Arafat, Hassan A; Daoud, Raeda; Shwahneh, Hadeel

    2009-01-01

    Litter is recognized as a form of street pollution and a key issue for solid waste managers. Nablus district (West Bank, Palestinian Territory), which has an established network of urban and rural roads, suffers from a wide-spread litter problem that is associated with these roads and is growing steadily with a well-felt negative impact on public health and the environment. The purpose of this research was to study the effects of four socio-economic characteristics (gender, income, marital status, and religious convictions) of district residents on their attitudes, practices, and behavior regarding street litter generation and to suggest possible remedial actions. All four characteristics were found to have strong correlations, not only with littering behavior and practices, but also with potential litter prevention strategies. In particular, the impact of religious convictions of the respondents on their littering habits and attitudes was very clear and interesting to observe.

  1. Effect of cage vs. floor litter environments on the pulmonary hypertensive response to intravenous endotoxin and on blood-gas values in broilers.

    PubMed

    Wang, W; Erf, G F; Wideman, R F

    2002-11-01

    Intravenous endotoxin has been shown to trigger a delayed pulmonary hypertensive response that varies widely in magnitude and duration among individual broilers. It was proposed that this individual variability may reflect immunological differences acquired during previous respiratory challenges that might have subsequently altered the endotoxin-initiated biochemical cascade. In Experiment 1, we tested the hypothesis that, when compared with broilers reared in clean stainless steel cages (Cage group), broilers reared on floor litter (Floor group) should experience a greater respiratory challenge and therefore may consistently exhibit a more enhanced pulmonary hypertensive response to intravenous endotoxin. Birds in the Cage group were grown in stainless steel cages at a low density (72 birds/8 m2 chamber), and fecal and dander materials were removed daily. Birds in the Floor group were reared on wood-shavings litter at a higher density (110 birds/8 m2 chamber). Pulmonary and systemic mean arterial pressures and blood-gas values were evaluated prior to and following the intravenous administration of 1 mg Salmonella typhimurium endotoxin. Broilers in the Floor and Cage groups exhibited pulmonary hypertensive responses to endotoxin that were very similar in terms of time of onset, duration, and magnitude, as well as variability in the response among individuals. Systemic hypotension also developed similarly in both groups following endotoxin injection. Blood-gas values indicated that the partial pressure of CO2 and the HCO3- concentration in arterial blood were higher (P < 0.05) in the Floor group than in the Cage group prior to and subsequent to the endotoxin injection. In Experiment 2, we reevaluated the effect of a dirty vs. a clean environment on blood-gas values using a different strain of broilers, and confirmed the negative impact of floor rearing on blood-gas values. We conclude that broilers reared on the floor inhaled litter dust and noxious fumes, which

  2. Effect of crude protein concentration and dietary electrolyte balance on litter quality, foot pad dermatitis, growth performance and processing yields in two medium heavy turkey hybrids.

    PubMed

    Veldkamp, T; Hocking, P M; Vinco, L J

    2017-10-01

    1. An experiment was conducted to investigate the effect of crude protein (CP) concentration and dietary electrolyte balance (DEB) on growth performance, processing yields, litter quality and foot pad dermatitis (FPD) in male turkeys from two commercial hybrids. Soya bean meal was replaced by vegetable protein sources selected for lower K concentrations to lower DEB in order to improve litter quality and subsequent quality of foot pads. 2. Effects of CP on litter friability and wetness were not consistent during the production period. FPD in turkeys fed on diets with low CP was significantly lower than FPD in turkeys fed on diets with high CP until 84 d. Growth performance was adversely affected at low CP. Processing yields were not affected by CP. 3. Litter was significantly dryer in pens of turkeys fed on diets with low DEB than in pens of turkeys fed on diets with high DEB. FPD in turkeys fed on diets with low DEB was significantly lower than in turkeys fed on diets with high DEB. Growth performance and processing yields were adversely affected at low DEB. 4. FPD in turkey hybrid A was higher than in turkey hybrid B at 28 d of age. Thereafter, no differences in FPD between turkey hybrids were observed. Growth performance and processing yields were not affected by turkey hybrid. 5. Overall, a significant interaction effect of CP × DEB was observed for FCR: in turkeys fed on the high DEB treatment, FCR of turkeys fed on the high CP diets was lower than FCR of turkeys fed on the low CP (LCP) diets whereas on the low DEB treatment, FCR was not affected by CP treatment. 6. It was concluded that litter quality can be improved and FPD may be decreased in turkeys fed on diets containing lower CP and DEB levels.

  3. XANES Spectroscopic Analysis of Phosphorus Speciation in Alum-Amended Poultry Litter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seiter,J.; Staats-Borda, K.; Ginder-Vogel, M.

    2008-01-01

    Aluminum sulfate (alum; Al2(SO4)3{center_dot}14H2O) is used as a chemical treatment of poultry litter to reduce the solubility and release of phosphate, thereby minimizing the impacts on adjacent aquatic ecosystems when poultry litter is land applied as a crop fertilizer. The objective of this study was to determine, through the use of X-ray absorption near edge structure (XANES) spectroscopy and sequential extraction, how alum amendments alter P distribution and solid-state speciation within the poultry litter system. Our results indicate that traditional sequential fractionation procedures may not account for variability in P speciation in heterogeneous animal manures. Analysis shows that NaOH-extracted Pmore » in alum amended litters is predominantly organic ({approx}80%), whereas in the control samples, >60% of NaOH-extracted P was inorganic P. Linear least squares fitting (LLSF) analysis of spectra collected of sequentially extracted litters showed that the P is present in inorganic (P sorbed on Al oxides, calcium phosphates) and organic forms (phytic acid, polyphosphates, and monoesters) in alum- and non-alum-amended poultry litter. When determining land application rates of poultry litter, all of these compounds must be considered, especially organic P. Results of the sequential extractions in conjunction with LLSF suggest that no P species is completely removed by a single extractant. Rather, there is a continuum of removal as extractant strength increases. Overall, alum-amended litters exhibited higher proportions of Al-bound P species and phytic acid, whereas untreated samples contained Ca-P minerals and organic P compounds. This study provides in situ information about P speciation in the poultry litter solid and about P availability in alum- and non-alum-treated poultry litter that will dictate P losses to ground and surface water systems.« less

  4. Climatic effects on decomposing litter and substrate chemistry along climatological gradients.

    NASA Astrophysics Data System (ADS)

    Berg, B.

    2009-04-01

    Climatic effects on decomposing litter and substrate chemistry along climatological gradients. B. Berg, Dipartimento Biologia Strutturale e Funzionale, Complesso Universitario, Monte San Angelo, via Cintia, I-80126 Napoli, Italy and Department of Forest Ecology, P.O. Box 27, University of Helsinki, FIN-00014, Helsinki, Finland. Studies of several processes, using climatic gradients do provide new information as compared with studies at e.g. a single site. Decomposition of plant litter in such gradients give response in decomposition rates to natural climate conditions. Thus Scots pine needle litter incubated in a climate gradient with annual average temperature (AVGT) ranging from -0.5 to 6.8oC had a highly significant increase in initial mass-loss rate with R2 = 0.591 (p<0.001) and a 5o increase in temperature doubled the mass-loss rate. As a contrast - needle litter of Norway spruce incubated in the same transect had no significant response to climate and for initial litter a 5o increase increased mass-loss rate c. 6%. For more decomposed Scots pine litter we could see that the effect of temperature on mass-loss rate gradually decreased until it disappeared. Long-term decomposition studies revealed differences in litter decomposition patterns along a gradient, even for the same type of litter. This could be followed by using an asymptotic function that gave, (i) a measure a maximum level of decomposition, (ii) the initial decomposition rate. Over a gradient the calculated maximum level of decomposition decreased with increasing AVGT. Other gradient studies revealed an effect of AVGT on litter chemical composition. Pine needle litter from stands under different climate conditions had nutrient concentrations related to AVGT. Thus N, P, K, and S were positively related to AVGT and Mn negatively, all of them significantly. This information may be used to explain the changing pattern in decomposition over the gradient.

  5. Factors influencing litter size and puppy losses in the Entlebucher Mountain dog.

    PubMed

    Schrack, J; Dolf, G; Reichler, I M; Schelling, C

    2017-06-01

    A good reproductive performance is a central element of animal breeding. The breeders of Entlebucher Mountain dogs observed a decrease of the mean litter size and an increase of the number of unsuccessful matings in the past years. The aim of the present study was to identify factors with an influence on fertility in this breed. In total, 915 litters from 202 sires and 348 dams from 1986 to 2013 entered the analyses. The total puppy losses (7.4%) reduced the mean litter size at birth of 5.49 ± 2.13 to a mean litter size at registration of 5.08 ± 2.05. There was no deviation from the expected equal sex distribution for puppies at birth and at registration, as well as for puppy losses consisting of stillborn puppies and puppies which died or had to be euthanized before registration. The mean annual litter inbreeding coefficient increased from 0.37 in 1986 to 0.40 in 2013 and was correlated with the year of birth of the litter (Kendall's tau b = 0.46). The age of the dam and parental inbreeding were identified as significant predictors with a negative effect on litter size at birth. For the litter size at registration the age and inbreeding of the dam had a significant negative effect and a 1% increase of dam inbreeding is expected to decrease the litter size at birth and registration by 0.1 and 0.09 puppies, respectively. The occurrence of total puppy losses decreased during the years and was more frequent in larger litters. In addition, in litters of older parents the occurrence of puppy losses was more frequent than in litters from younger parents. The final generalized linear mixed-effects models for litter size at birth, litter size at registration and for total puppy losses explained 36%, 33% and 22% of the total variance, respectively. The impact of inbreeding and parental age on fertility of the Entlebucher Mountain dog was small and the influence of the dam was much bigger than the one of the sire. Other factors must be responsible for the variability

  6. Floating marine litter as a raft for drifting voyages for Planes minutus (Crustacea: Decapoda: Grapsidae) and Liocarcinus navigator (Crustacea: Decapoda: Polybiidae).

    PubMed

    Tutman, P; Kapiris, K; Kirinčić, M; Pallaoro, A

    2017-07-15

    The Columbus crab Planes minutus and Arch-fronted swimming crab Liocarcinus navigator, within their distribution ranges in the Mediterranean, were found rafted on plastic macro-litter floating on the open south Adriatic. While P. minutus was recorded from inanimate flotsam outside of the Mediterranean, L. navigator is herein reported for the first time on floating marine litter. The role of floating litter as habitat or as a dispersal agent for marine invertebrates has received quite attention however, records of decapod crabs drifting on litter has been relatively sparse. Our results suggests that vast quantities of floating debris, comprised primarily of non-biodegradable plastic polymers, probably will augment natural floating substrates in the marine environment, potentially facilitating the spread of invasive species. The dispersion of rafting crabs through floating debris should be investigated given the high potential ecological risk of invasion by exotic species due to the increase in waste production (ecological risk assessment). Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Litters of photosynthetically divergent grasses exhibit differential metabolic responses to warming and elevated CO2

    USDA-ARS?s Scientific Manuscript database

    Climatic stress induced by warming can alter plant metabolism, leading to changes in litter chemistry that can affect soil carbon cycling. Elevated CO2 could partly mitigate warming induced moisture stress, and the degree of this mitigation may vary with plant functional types. We hypothesized that,...

  8. Hyperspectral remote sensing tools for quantifying plant litter and invasive species in arid ecosystems

    USGS Publications Warehouse

    Nagler, Pamela L.; Sridhar, B.B. Maruthi; Olsson, Aaryn Dyami; Glenn, Edward P.; van Leeuwen, Willem J.D.; Thenkabail, Prasad S.; Huete, Alfredo; Lyon, John G.

    2012-01-01

    Green vegetation can be distinguished using visible and infrared multi-band and hyperspectral remote sensing methods. The problem has been in identifying and distinguishing the non-photosynthetically active radiation (PAR) landscape components, such as litter and soils, and from green vegetation. Additionally, distinguishing different species of green vegetation is challenging using the relatively few bands available on most satellite sensors. This chapter focuses on hyperspectral remote sensing characteristics that aim to distinguish between green vegetation, soil, and litter (or senescent vegetation). Quantifying litter by remote sensing methods is important in constructing carbon budgets of natural and agricultural ecosystems. Distinguishing between plant types is important in tracking the spread of invasive species. Green leaves of different species usually have similar spectra, making it difficult to distinguish between species. However, in this chapter we show that phenological differences between species can be used to detect some invasive species by their distinct patterns of greening and dormancy over an annual cycle based on hyperspectral data. Both applications require methods to quantify the non-green cellulosic fractions of plant tissues by remote sensing even in the presence of soil and green plant cover. We explore these methods and offer three case studies. The first concerns distinguishing surface litter from soil using the Cellulose Absorption Index (CAI), as applied to no-till farming practices where plant litter is left on the soil after harvest. The second involves using different band combinations to distinguish invasive saltcedar from agricultural and native riparian plants on the Lower Colorado River. The third illustrates the use of the CAI and NDVI in time-series analyses to distinguish between invasive buffelgrass and native plants in a desert environment in Arizona. Together the results show how hyperspectral imagery can be applied to

  9. Production of litter and detritus related to the density of mangrove

    NASA Astrophysics Data System (ADS)

    Budi Mulya, Miswar; Arlen, HJ

    2018-03-01

    Research about the production of leaf litter and detritus related to the density of mangrove trees has been done. The aims of this research are to know and analyze the amount of litter and detritus produced to the density of mangrove trees. The production and collection of leaf litter were carried out in five stations. Production of detritus and decomposition rate were calculated by measuring its dry weight. The density and level of mangrove trees were determined using transect quadratic method. The relationship between the leaf litter and detritus production ratio related to mangrove density were then analyzed. Results showed that mangrove trees with the density of 766.67 ind ha‑1 ccould produce the amount of litter and detritus to about 28597.33 gha‑1day‑1and 1099.35 gha‑1day‑1 while mangrove trees with the density of 1300 ind ha‑1 could produce the amount of litter and detritus to about 35093.33 g/ha/day and 1216.68 gha‑1day‑1 respectively. Data analysis showed that the increment of mangrove density is linearly related to the production increment of litter and detritus.

  10. Litter dynamics in two Sierran mixed conifer forests. II. Nutrient release in decomposing leaf litter

    USGS Publications Warehouse

    Stohlgren, Thomas J.

    1988-01-01

    The factors influencing leaf litter decomposition and nutrient release patterns were investigated for 3.6 years in two mixed conifer forests in the southern Sierra Nevada of California. The giant sequoia–fir forest was dominated by giant sequoia (Sequoiadendrongiganteum (Lindl.) Buchh.), white fir (Abiesconcolor Lindl. & Gord.), and sugar pine (Pinuslambertiana Dougl.). The fir–pine forest was dominated by white fir, sugar pine, and incense cedar (Calocedrusdecurrens (Torr.) Florin). Initial concentrations of nutrients and percent lignin, cellulose, and acid detergent fiber vary considerably in freshly abscised leaf litter of the studied species. Giant sequoia had the highest concentration of lignin (20.3%) and the lowest concentration of nitrogen (0.52%), while incense cedar had the lowest concentration of lignin (9.6%) and second lowest concentration of nitrogen (0.63%). Long-term (3.6 years) foliage decomposition rates were best correlated with initial lignin/N (r2 = 0.94, p r2 = 0.92, p r2 = 0.80, p < 0.05). Patterns of nutrient release were highly variable. Giant sequoia immobilized N and P, incense cedar immobilized N and to a lesser extent P, while sugar pine immobilized Ca. Strong linear or negative exponential relationships existed between initial concentrations of N, P, K, and Ca and percent original mass remaining of those nutrients after 3.6 years. This suggests efficient retention of these nutrients in the litter layer of these ecosystems. Nitrogen concentrations steadily increase in decomposing leaf litter, effectively reducing the C/N ratios from an initial range of 68–96 to 27–45 after 3.6 years.

  11. Effect of litter moisture on the development of footpad dermatitis in broiler chickens.

    PubMed

    Taira, Kazuyo; Nagai, Toshimune; Obi, Takeshi; Takase, Kozo

    2014-04-01

    Broiler chicks were reared on either wet litter or dry litter to compare the development of footpad dermatitis (FPD). Broilers reared on wet litter first developed FPD at 14 days of age. Their FPD scores increased sharply after 21 days of age, reaching 2.92 at 42 days. In broilers reared on dry litter, FPD was first observed at 28 days of age, and the FPD score was only 0.70 at 42 days. When 21- or 28-day-old broilers that had been reared on wet litter and had developed FPD were moved to dry litter, the progression of FPD was suppressed or delayed. These results suggest that reducing litter moisture is effective in preventing FPD and suppressing disease progression.

  12. Effect of Litter Moisture on the Development of Footpad Dermatitis in Broiler Chickens

    PubMed Central

    TAIRA, Kazuyo; NAGAI, Toshimune; OBI, Takeshi; TAKASE, Kozo

    2013-01-01

    ABSTRACT Broiler chicks were reared on either wet litter or dry litter to compare the development of footpad dermatitis (FPD). Broilers reared on wet litter first developed FPD at 14 days of age. Their FPD scores increased sharply after 21 days of age, reaching 2.92 at 42 days. In broilers reared on dry litter, FPD was first observed at 28 days of age, and the FPD score was only 0.70 at 42 days. When 21- or 28-day-old broilers that had been reared on wet litter and had developed FPD were moved to dry litter, the progression of FPD was suppressed or delayed. These results suggest that reducing litter moisture is effective in preventing FPD and suppressing disease progression. PMID:24366153

  13. Non-human primates avoid the detrimental effects of prenatal androgen exposure in mixed-sex litters: combined demographic, behavioral, and genetic analyses.

    PubMed

    Bradley, Brenda J; Snowdon, Charles T; McGrew, William C; Lawler, Richard R; Guevara, Elaine E; McIntosh, Annick; O'Connor, Timothy

    2016-12-01

    Producing single versus multiple births has important life history trade-offs, including the potential benefits and risks of sharing a common in utero environment. Sex hormones can diffuse through amniotic fluid and fetal membranes, and females with male littermates risk exposure to high levels of fetal testosterone, which are shown to have masculinizing effects and negative fitness consequences in many mammals. Whereas most primates give birth to single offspring, several New World monkey and strepsirrhine species regularly give birth to small litters. We examined whether neonatal testosterone exposure might be detrimental to females in mixed-sex litters by compiling data from long-term breeding records for seven primate species (Saguinus oedipus; Varecia variegata, Varecia rubra, Microcebus murinis, Mirza coquereli, Cheirogaleus medius, Galago moholi). Litter sex ratios did not differ from the expected 1:2:1 (MM:MF:FF for twins) and 1:2:2:1 (MMM:MMF:MFF:FFF for triplets). Measures of reproductive success, including female survivorship, offspring-survivorship, and inter-birth interval, did not differ between females born in mixed-sex versus all-female litters, indicating that litter-producing non-human primates, unlike humans and rodents, show no signs of detrimental effects from androgen exposure in mixed sex litters. Although we found no evidence for CYP19A1 gene duplications-a hypothesized mechanism for coping with androgen exposure-aromatase protein evolution shows patterns of convergence among litter-producing taxa. That some primates have effectively found a way to circumvent a major cost of multiple births has implications for understanding variation in litter size and life history strategies across mammals. © 2016 Wiley Periodicals, Inc.

  14. Managing broiler litter application rate and grazing to decrease watershed runoff losses.

    PubMed

    Sistani, K R; Brink, G E; Oldham, J L

    2008-01-01

    Pasture management and broiler litter application rate are critical factors influencing the magnitude of nutrients being transported by runoff from fields. We investigated the impact of pasture management and broiler litter application rate on nutrient runoff from bermudagrass (Cynodon dactylon) pastures. The experiment was conducted on a Ruston fine sandy loam with a factorial arrangement on 21 large paddocks. Runoff water was collected from natural rainfall events from 2001 to 2003. Runoff water and soil samples were analyzed for nutrients and sediments. Runoff was generally greater (29%) from grazed than hayed pastures regardless of the litter application rate. There was greater inorganic N in the runoff from grazed paddocks when litter rate was based on N rather than P. The mean total P loss per runoff event for all treatments ranged from 7 to 45 g ha(-1) and the grazed treatment with litter applied on N basis had the greatest total P loss. Total dissolved P was the dominant P fraction in the runoff, ranging from 85% to 93% of the total P. The soluble reactive P was greater for treatments with litter applied on N basis regardless of pasture management. Runoff total sediments were greater for N-based litter application compared to those which received litter on P basis. Our results indicate that litter may be applied on N basis if the pasture is hayed and the soil P is low. In contrast, litter rates should be based on a P-basis if pasture is grazed.

  15. Microbial Environment Affects Innate Immunity in Two Closely Related Earthworm Species Eisenia andrei and Eisenia fetida

    PubMed Central

    Dvořák, Jiří; Mančíková, Veronika; Pižl, Václav; Elhottová, Dana; Šilerová, Marcela; Roubalová, Radka; Škanta, František; Procházková, Petra; Bilej, Martin

    2013-01-01

    Survival of earthworms in the environment depends on their ability to recognize and eliminate potential pathogens. This work is aimed to compare the innate defense mechanisms of two closely related earthworm species, Eisenia andrei and Eisenia fetida, that inhabit substantially different ecological niches. While E. andrei lives in a compost and manure, E. fetida can be found in the litter layer in forests. Therefore, the influence of environment-specific microbiota on the immune response of both species was followed. Firstly, a reliable method to discern between E. andrei and E. fetida based on species-specific primers for cytochrome c oxidase I (COI) and stringent PCR conditions was developed. Secondly, to analyze the immunological profile in both earthworm species, the activity and expression of lysozyme, pattern recognition protein CCF, and antimicrobial proteins with hemolytic function, fetidin and lysenins, have been assessed. Whereas, CCF and lysozyme showed only slight differences in the expression and activity, fetidin/lysenins expression as well as the hemolytic activity was considerably higher in E. andrei as compared to E. fetida. The expression of fetidin/lysenins in E. fetida was not affected upon the challenge with compost microbiota, suggesting more substantial changes in the regulation of the gene expression. Genomic DNA analyses revealed significantly higher level of fetidin/lysenins (determined using universal primer pairs) in E. andrei compared to E. fetida. It can be hypothesized that E. andrei colonizing compost as a new habitat acquired an evolutionary selection advantage resulting in a higher expression of antimicrobial proteins. PMID:24223917

  16. Observations of mixed-aged litters in brown bears

    USGS Publications Warehouse

    Swenson, J.E.; Haroldson, M.A.

    2008-01-01

    We report on 3 cases of mixed-aged litters (young born in different years) in brown bears (Ursus arctos); in 1 instance the cub-of-the-year (hereafter called cubs) died in the den. Two cases occurred in Sweden after mothers were separated from their young during the breeding season. In one, the mother was separated from the accompanying cub for at least 12.5 hours and possibly up to 3.3 days, and later possibly separated for 4 days. In the other, the mother was separated from her yearling at least 3 times for 1-14, 1-6 and 1-6 days. She was with a male during the first separation. Specific events that produced the mixed-aged litter observed in Greater Yellowstone Ecosystem were unknown and our interpretation is based on estimates of ages of accompanying young from photographs. The observation of only 2 mixed-aged litters, after den emergence, from a sample of 406 observed cub litters accompanying radiomarked females confirms the rarity of this phenomenon. The mechanism apparently includes a short separation of mother and young, and, in the case of cubs, the mother must mate while lactating. Better understanding of the physiological mechanisms that allow mixed-age litters would help us in the debate about the occurrence of sexually selected infanticide in bears.

  17. Enhanced solid waste management by understanding the effects of gender, income, marital status, and religious convictions on attitudes and practices related to street littering in Nablus - Palestinian territory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Khatib, Issam A.; Arafat, Hassan A.; Daoud, Raeda

    Litter is recognized as a form of street pollution and a key issue for solid waste managers. Nablus district (West Bank, Palestinian Territory), which has an established network of urban and rural roads, suffers from a wide-spread litter problem that is associated with these roads and is growing steadily with a well-felt negative impact on public health and the environment. The purpose of this research was to study the effects of four socio-economic characteristics (gender, income, marital status, and religious convictions) of district residents on their attitudes, practices, and behavior regarding street litter generation and to suggest possible remedial actions.more » All four characteristics were found to have strong correlations, not only with littering behavior and practices, but also with potential litter prevention strategies. In particular, the impact of religious convictions of the respondents on their littering habits and attitudes was very clear and interesting to observe.« less

  18. Integrating plant litter quality, soil organic matter stabilization, and the carbon saturation concept.

    PubMed

    Castellano, Michael J; Mueller, Kevin E; Olk, Daniel C; Sawyer, John E; Six, Johan

    2015-09-01

    Labile, 'high-quality', plant litters are hypothesized to promote soil organic matter (SOM) stabilization in mineral soil fractions that are physicochemically protected from rapid mineralization. However, the effect of litter quality on SOM stabilization is inconsistent. High-quality litters, characterized by high N concentrations, low C/N ratios, and low phenol/lignin concentrations, are not consistently stabilized in SOM with greater efficiency than 'low-quality' litters characterized by low N concentrations, high C/N ratios, and high phenol/lignin concentrations. Here, we attempt to resolve these inconsistent results by developing a new conceptual model that links litter quality to the soil C saturation concept. Our model builds on the Microbial Efficiency-Matrix Stabilization framework (Cotrufo et al., 2013) by suggesting the effect of litter quality on SOM stabilization is modulated by the extent of soil C saturation such that high-quality litters are not always stabilized in SOM with greater efficiency than low-quality litters. © 2015 John Wiley & Sons Ltd.

  19. Impact of fungicides on the diversity and function of non-target ammonia-oxidizing microorganisms residing in a litter soil cover.

    PubMed

    Puglisi, Edoardo; Vasileiadis, Sotirios; Demiris, Konstantinos; Bassi, Daniela; Karpouzas, Dimitrios G; Capri, Ettore; Cocconcelli, Pier S; Trevisan, Marco

    2012-10-01

    Litter soil cover constitutes an important micro-ecosystem in sustainable viticulture having a key role in nutrient cycling and serving as a habitat of complex microbial communities. Ammonia-oxidizing bacteria (AOB) and archaea (AOA) are known to regulate nitrification in soil while little is known regarding their function and diversity in litter. We investigated the effects of two fungicides, penconazole and cyprodinil, commonly used in vineyards, on the function and diversity of total and active AOB and AOA in a microcosm study. Functional changes measured via potential nitrification and structural changes assessed via denaturating gradient gel electrophoresis (DGGE) at the DNA and RNA levels were contrasted with pesticide dissipation in the litter layer. The latter was inversely correlated with potential nitrification, which was temporarily inhibited at the initial sampling dates (0 to 21 days) when nearly 100 % of the applied pesticide amounts was still present in the litter. Fungicides induced changes in AOB and AOA communities with RNA-DGGE analysis showing a higher sensitivity. AOA were more responsive to pesticide application compared to AOB. Potential nitrification was less sensitive to the fungicides and was restored faster than structural changes, which persisted. These results support the theory of microbial redundancy for nitrification in a stressed litter environment.

  20. Effect of Poultry Litter Treatment (PLT) on death due to ascites in broilers.

    PubMed

    Terzich, M; Quarles, C; Goodwin, M A; Brown, J

    1998-01-01

    The purposes of this study were to determine the effect of Poultry Litter Treatment (PLT) on levels of litter moisture, litter nitrogen, atmospheric ammonia, and death due to ascites. Data were collected from chicks raised in containment conditions that resembled commercial settings. The ascites death rate (5.9%) in broiler chicks on PLT-treated litter was significantly (chi 2 = 15.5, df = 1, P = 0.0001) lower than that (31.5%) in broiler chicks raised on untreated litter. Likewise, atmospheric ammonia levels in pens that had been treated with PLT were significantly (P < 0.05) lower than those in pens that received no treatment. Under the conditions of the present study, litter moisture and litter nitrogen levels were not different (P > 0.05) among treatments at any sample interval.

  1. Considering Affective Responses towards Environments for Enhancing Location Based Services

    NASA Astrophysics Data System (ADS)

    Huang, H.; Gartner, G.; Klettner, S.; Schmidt, M.

    2014-04-01

    A number of studies in the field of environmental psychology show that humans perceive and evaluate their surroundings affectively. Some places are experienced as unsafe, while some others as attractive and interesting. Experiences from daily life show that many of our daily behaviours and decision-making are often influenced by this kind of affective responses towards environments. Location based services (LBS) are often designed to assist and support people's behaviours and decision-making in space. In order to provide services with high usefulness (usability and utility), LBS should consider these kinds of affective responses towards environments. This paper reports on the results of a research project, which studies how people's affective responses towards environments can be modelled and acquired, as well as how LBS can benefit by considering these affective responses. As one of the most popular LBS applications, mobile pedestrian navigation systems are used as an example for illustration.

  2. Initial Soil Organic Matter Content Influences the Storage and Turnover of Litter-, Root- and Soil Carbon in Grasslands

    NASA Astrophysics Data System (ADS)

    Liu, L.; Xu, S.; Li, P.; Sayer, E. J.

    2017-12-01

    Grassland degradation is a worldwide problem that often leads to substantial loss of soil organic matter (SOM). Understanding how SOM content influences the stabilization of plant carbon (C) to form soil C is important to evaluate the potential of degraded grasslands to sequester additional C. We conducted a greenhouse experiment using C3 soils with six levels of SOM content and planted the C4 grass Cleistogenes squarrosa and/or added its litter to investigate how SOM content regulates the storage of new soil C derived from litter and roots, the decomposition of extant soil C, and the formation of soil aggregates. We found that microbial biomass carbon (MBC) increased with SOM content, and increased the mineralization of litter C. Both litter addition and planted treatments increased the amount of new C inputs to soil. However, litter addition had no significant impacts on the mineralization of extant soil C, but the presence of living roots significantly accelerated it. Thus, by the end of the experiment, soil C content was significantly higher in the litter addition treatments, but was not affected by planted treatments. The soil macroaggregate fraction increased with SOM content and was positively related to MBC. Overall, our study suggests that as SOM content increases, plant growth and soil microbes become more active, which allows microbes to process more plant-derived C and increases new soil C formation. The interactions between SOM content and plant C inputs should be considered when evaluating soil C turnover in degraded grasslands.

  3. Long-term dynamics of pine and hardwood litter in contrasting environments: Toward a global model of decomposition

    Treesearch

    Henry L. Gholz; David A. Wedin; Stephen M. Smitherman; Mark E. Harmon; William J. Parton

    2000-01-01

    We analysed data on mass loss after five years of decomposition in the field from both fine root and leaf litters from two highly contrasting trees, Drypetes glallca, a tropical hardwood tree from Puerto Rico, and pine species from North America as part of the Long-Term Intersite Decomposition Experiment (LIDET). LIDET is a reciprocal litterbag study...

  4. Plastic litter in sediments from the coasts of south Tuscany (Tyrrhenian Sea).

    PubMed

    Cannas, Susanna; Fastelli, Paolo; Guerranti, Cristiana; Renzi, Monia

    2017-06-15

    This study estimated the total loads of plastic litter (macro-meso- and micro-plastics) in sediments from a wide stretch of marine and coastal environment of Tyrrhenian Sea. The prevailing category of debris was microplastic. The results obtained, in terms of average amount of microplastic per kilogram of dry sediment, are in agreement with data reported by various Authors internationally. The study area resulted to be uniform for plastic items levels. Particularly evident was the influence of a flood, occurred in November 2012 in Talamone, on sediments collected at the harbour of this locality: in this area, a difference in levels and quality of plastic debris, attributable to periods before and after the flood, was observed in sediments. In addition to focusing on the effect of this phenomenon, this study gives an important overview, for what concerns the presence of plastic litter, of a significant naturalistic area. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effect of litter, leaf cover and cover of basal internodes of the dominant species Molinia caerulea on seedling recruitment and established vegetation

    NASA Astrophysics Data System (ADS)

    Janeček, Štěpán; Lepš, Jan

    2005-09-01

    The effects of litter removal, leaf cover of established plants and cover of basal internodes of a dominant species Molinia caerulea on seedling germination and the dynamics of established plants were studied in a field experiment in an oligotrophic wet meadow. Although the negative influence of litter on total seedling number and seedling species composition was non-significant, litter significantly affected the dynamics of the established vegetation and caused inhibition of total leaf cover development. The effects of total leaf cover of established plants on seedling establishment changed during the vegetation season. Whereas the effect of total leaf cover was positive at the start and in the middle of the vegetation season, at the end the total leaf cover negatively affected seedling establishment. Both total leaf cover and cover of basal internodes affected seedling composition. Effects of these two variables were statistically separable suggesting that they are based on different mechanisms. The response of seedling establishment to these factors was species specific and, consequently, our data support the hypothesis that that biotically generated spatial heterogeneity can promote species co-existence through the differentiation of species regeneration niches.

  6. Maternal presence and environmental enrichment affect food neophobia of piglets

    PubMed Central

    Oostindjer, Marije; Muñoz, Julia Mas; Van den Brand, Henry; Kemp, Bas; Bolhuis, J. Elizabeth

    2011-01-01

    Young omnivores show food neophobia in order to avoid the potential harmful effects of ingesting unfamiliar food items. We investigated whether the presence of the mother and an enriched rearing environment would reduce food neophobia in piglets. A mother may provide information on suitable food types to include in the diet, whereas an enriched environment may stimulate behavioural development and reduce reactivity towards novel stimuli (including food). Five barren-reared or enriched-reared piglets per litter were exposed to two novel food items in the presence, and the other five per litter in the absence, of the mother in a 7 min test. Maternal presence reduced food neophobia profoundly as reflected in a reduced latency to touching the food, a higher proportion of piglets sampling the two different food items and a higher intake. Latency to touch the food, however, was affected by maternal presence more strongly for barren-reared piglets than for enriched-reared piglets, and in the absence of the sow, consumption of one novel food type and time spent in the feeding area were higher for enriched-reared piglets. Environmental enrichment does have the potential to reduce food neophobia, but the presence of the mother during the encounter with novel food seems more efficient in decreasing food neophobia of piglets. PMID:20554557

  7. INVASIVE GRASS ALTERS LITTER DECOMPOSITION BY INFLUENCING MACRO-DETRITIVORES

    EPA Science Inventory

    Nitrogen fertilization experiments have produced results with inconsistent rates of plant litter decomposition, a phenomenon that may be explained if the influence of animal detritivores (macro-detritivores) on litter mass loss is greater than that of microbial decomposers whose ...

  8. Can species-specific differences in foliar chemistry influence leaf litter decomposition in grassland species?

    NASA Astrophysics Data System (ADS)

    Sanaullah, M.; Chabbi, A.; Rumpel, C.

    2009-04-01

    The influence of litter quality on its rate of decomposition is a crucial aspect of C cycle. In this study we concentrated on grassland ecosystems where leaf litter is one of the major sources of C input. To quantify the contribution of initial leaf chemistry within different plant species, the decomposition of chemically different leaf litter of three grassland species (Lolium perenne, Festuca arundinacea and Dactylis glomerata) was monitored, using the litter bag technique. Litter of different maturity stages i.e. green (fresh leaves) and brown litter (brown leaves were still attached to the plant), were incubated on bare soil surface. Samples were taken at different time intervals (0, 2, 4, 8, 20 and 44 weeks) and were analyzed for mass loss, organic C and N contents and stable isotopic signatures (C and N). Changes in litter chemistry were addressed by determining lignin-derived phenols after CuO oxidation and non-cellulosic polysaccharides after acid hydrolysis followed by gas chromatography. Green litter was chemically different from brown litter due to higher initial N and lower lignin contents. While in grassland species, both L. perenne and D. glomerata were similar in their initial chemical composition compared with F. arundinacea. Green litter showed higher rate of degradation. In green litter, Percent lignin remaining of initial (% OI) followed the similar decomposition pattern as of C remaining indicating lignin as controlling factor in decomposition. Constant Acid-to-Aldehyde ratios of lignin-derived phenols (vanillyl and syringyl) did not suggest any transformation in lignin structures. In green litter, increase in non-cellulosic polysaccharides ratios (C6/C5 and deoxy/C5) proposed microbial-derived sugars, while there was no significant increase in these ratios in brown litter. In conclusion, due to the differences in initial chemical composition (initial N and lignin contents), green litter decomposition was higher than brown litter in all

  9. Estimating litter carbon stocks on forest land in the United States

    Treesearch

    Grant M. Domke; Charles H. (Hobie) Perry; Brian F. Walters; Christopher W. Woodall; Matthew B. Russell; James E. Smith

    2016-01-01

    Forest ecosystems are the largest terrestrial carbon sink on earth, withmore than half of their net primary productionmoving to the soil via the decomposition of litter biomass. Therefore, changes in the litter carbon (C) pool have important implications for global carbon budgets and carbon emissions reduction targets and negotiations. Litter accounts for an estimated...

  10. Fire affects root decomposition, soil food web structure, and carbon flow in tallgrass prairie

    NASA Astrophysics Data System (ADS)

    Shaw, E. Ashley; Denef, Karolien; Milano de Tomasel, Cecilia; Cotrufo, M. Francesca; Wall, Diana H.

    2016-05-01

    Root litter decomposition is a major component of carbon (C) cycling in grasslands, where it provides energy and nutrients for soil microbes and fauna. This is especially important in grasslands where fire is common and removes aboveground litter accumulation. In this study, we investigated whether fire affects root decomposition and C flow through the belowground food web. In a greenhouse experiment, we applied 13C-enriched big bluestem (Andropogon gerardii) root litter to intact tallgrass prairie soil cores collected from annually burned (AB) and infrequently burned (IB) treatments at the Konza Prairie Long Term Ecological Research (LTER) site. Incorporation of 13C into microbial phospholipid fatty acids and nematode trophic groups was measured on six occasions during a 180-day decomposition study to determine how C was translocated through the soil food web. Results showed significantly different soil communities between treatments and higher microbial abundance for IB. Root decomposition occurred rapidly and was significantly greater for AB. Microbes and their nematode consumers immediately assimilated root litter C in both treatments. Root litter C was preferentially incorporated in a few groups of microbes and nematodes, but depended on burn treatment: fungi, Gram-negative bacteria, Gram-positive bacteria, and fungivore nematodes for AB and only omnivore nematodes for IB. The overall microbial pool of root-litter-derived C significantly increased over time but was not significantly different between burn treatments. The nematode pool of root-litter-derived C also significantly increased over time, and was significantly higher for the AB treatment at 35 and 90 days after litter addition. In conclusion, the C flow from root litter to microbes to nematodes is not only measurable but also significant, indicating that higher nematode trophic levels are critical components of C flow during root decomposition, which, in turn, is significantly affected by fire. Not

  11. The generation and cost of litter resulting from the curbside collection of recycling.

    PubMed

    Wagner, Travis P; Broaddus, Nathan

    2016-04-01

    This study examined the generation of litter, defined as spillage and uncollected residue, from a curbside collection system for residential recycling. The primary recycling containers used in the study were 18-gal (68 L), open-top bins. The study, conducted over a seven-week period, was comprised of both an urban and suburban area. Six litter characterizations were conducted in which all new litter larger than 1 in.(2) was collected, segregated, counted, and weighed. We found that each week the open-top recycling bins contributed approximately 20,590 pieces of litter over 1 in. in size per every 1000 households, which resulted in the generation of 3.74 tons of litter per 1000 households per year. In addition to the bins having no top, the primary root causes of the litter were constantly overflowing recycling bins, the method of collection, and material scavenging. Based on an estimated cost of litter cleanup ranging from $0.17 to $0.79 per piece of litter, the direct economic costs from the collection of litter and loss in recycling revenues were estimated at US$3920 to US$19,250 per 1000 households per year. Other notable impacts from the litter, such as increased risk of flood damage from storm drain impairment and marine ecosystem damages exist, but were not monetized. The results strongly suggest that modification of the curbside collection system would decrease the amount and associated cost of litter by replacing existing curbside collection containers with larger volume containers with covers and by modifying the task-based incentive system to emphasize litter prevention rather than the current aim of completing the task most quickly. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Litter decomposition over broad spatial and long time scales investigated by advanced solid-state NMR: insight into effects of climate, litter quality, and time

    NASA Astrophysics Data System (ADS)

    Mao, J.; Chen, N.; Harmon, M. E.; Li, Y.; Cao, X.; Chappell, M.

    2012-12-01

    Advanced 13C solid-state NMR techniques were employed to study the chemical structural changes of litter decomposition across broad spatial and long time scales. The fresh and decomposed litter samples of four species (Acer saccharum (ACSA), Drypetes glauca (DRGL), Pinus resinosa (PIRE), and Thuja plicata (THPL)) incubated for up to 10 years at four sites under different climatic conditions (from Arctic to tropical forest) were examined. Decomposition generally led to an enrichment of cutin and surface wax materials, and a depletion of carbohydrates causing overall composition to become more similar compared with original litters. However, the changes of main constituents in the four litters were inconsistent with the four litters following different pathways of decomposition at the same site. As decomposition proceeded, waxy materials decreased at the early stage and then gradually increased in PIRE; DRGL showed a significant depletion of lignin and tannin while the changes of lignin and tannin were relative small and inconsistent for ACSA and THPL. In addition, the NCH groups, which could be associated with either fungal cell wall chitin or bacterial wall petidoglycan, were enriched in all litters except THPL. Contrary to the classic lignin-enrichment hypothesis, DRGL with low-quality C substrate had the highest degree of composition changes. Furthermore, some samples had more "advanced" compositional changes in the intermediate stage of decomposition than in the highly-decomposed stage. This pattern might be attributed to the formation of new cross-linking structures, that rendered substrates more complex and difficult for enzymes to attack. Finally, litter quality overrode climate and time factors as a control of long-term changes of chemical composition.

  13. Marine litter in an EBSA (Ecologically or Biologically Significant Area) of the central Mediterranean Sea: Abundance, composition, impact on benthic species and basis for monitoring entanglement.

    PubMed

    Consoli, Pierpaolo; Andaloro, Franco; Altobelli, Chiara; Battaglia, Pietro; Campagnuolo, Silvana; Canese, Simonepietro; Castriota, Luca; Cillari, Tiziana; Falautano, Manuela; Pedà, Cristina; Perzia, Patrizia; Sinopoli, Mauro; Vivona, Pietro; Scotti, Gianfranco; Esposito, Valentina; Galgani, Francois; Romeo, Teresa

    2018-05-01

    Marine litter is commonly observed everywhere in the ocean. In this study, we analyzed 17 km of video footage, collected by a Remotely Operated Vehicle (ROV) at depths ranging between 20 and 220 m, during 19 transects performed on the rocky banks of the Straits of Sicily. Recently, the Contracting Parties of the Convention on Biological Diversity (CBD) recognized this site as an Ecologically or Biologically Significant Area (EBSA). The research aim was to quantify the abundance of marine litter and its impact on benthic fauna. Litter density ranged from 0 items/100 m 2 to 14.02 items/100 m 2 with a mean (±standard error) of 2.13 (±0.84) items/100 m 2 . The observed average density was higher (5.2 items/100 m 2 ) at depths >100 m than at shallower depths (<100 m, 0.71 items/100 m 2 ). Lost or abandoned fishing lines contributed to 98.07% of the overall litter density, then representing the dominant source of marine debris. Litter interactions with fauna were frequently observed, with 30% of litter causing "entanglement/coverage" and 15% causing damage to sessile fauna. A total of 16 species showed interaction (entanglement/coverage or damage) with litter items and 12 of these are species of conservation concern according to international directives and agreements (CITES, Berne Convention, Habitat Directive, SPA/BD Protocol, IUCN Red List); we also observed 7 priority habitats of the SPA/BD Protocol. This research will support the implementation of monitoring "Harm" as recommended by the UN Environment/MAP Regional Plan on Marine Litter Management in the Mediterranean, and the Marine Strategy Framework Directive (MSFD). The institution of a SPAMI in the investigated area could represent a good management action for the protection of this hotspot of biodiversity and to achieve a Good Environmental Status (GES) for the marine environment by 2020, under the MSFD. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Loggerhead sea turtles (Caretta caretta): A target species for monitoring litter ingested by marine organisms in the Mediterranean Sea.

    PubMed

    Matiddi, Marco; Hochsheid, Sandra; Camedda, Andrea; Baini, Matteo; Cocumelli, Cristiano; Serena, Fabrizio; Tomassetti, Paolo; Travaglini, Andrea; Marra, Stefano; Campani, Tommaso; Scholl, Francesco; Mancusi, Cecilia; Amato, Ezio; Briguglio, Paolo; Maffucci, Fulvio; Fossi, Maria Cristina; Bentivegna, Flegra; de Lucia, Giuseppe Andrea

    2017-11-01

    Marine litter is any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the marine and coastal environment. Ingestion of marine litter can have lethal and sub-lethal effects on wildlife that accidentally ingests it, and sea turtles are particularly susceptible to this threat. The European Commission drafted the 2008/56/EC Marine Strategy Framework Directive with the aim to achieve a Good Environmental Status (GES), and the loggerhead sea turtle (Caretta caretta, Linnaeus 1758) was selected for monitoring the amount and composition of litter ingested by marine animals. An analogous decision has been made under the UNEP/MAP Barcelona Convention for the protection of the Mediterranean Sea, following the Ecosystem Approach. This work provides for the first time, two possible scenarios for the Marine Strategy Framework Directive GES, both related to "Trends in the amount and composition of litter ingested by marine animals" in the Mediterranean Sea. The study validates the use of the loggerhead turtle as target indicator for monitoring the impact of litter on marine biota and calls for immediate use of this protocol throughout the Mediterranean basin and European Region. Both GES scenarios are relevant worldwide, where sea turtles and marine litter are present, for measuring the impact of ingested plastics and developing policy strategies to reduce it. In the period between 2011 and 2014, 150 loggerhead sea turtles, found dead, were collected from the Italian Coast, West Mediterranean Sea Sub-Region. The presence of marine litter was investigated using a standardized protocol for necropsies and lab analysis. The collected items were subdivided into 4 main categories, namely, IND-Industrial plastic, USE-User plastic, RUB-Non plastic rubbish, POL-Pollutants and 14 sub-categories, to detect local diversity. Eighty-five percent of the individuals considered (n = 120) were found to have ingested an average of 1.3 ± 0.2 g of

  15. Total and water-soluble phosphorus in broiler litter over three flocks with alum litter treatment and dietary inclusion of high available phosphorus corn and phytase supplementation.

    PubMed

    Miles, D M; Moore, P A; Smith, D R; Rice, D W; Stilborn, H L; Rowe, D R; Lott, B D; Branton, S L; Simmons, J D

    2003-10-01

    Three pen trials were conducted to determine the main effect of alum addition to litter on form of poultry litter P using a 2 x 2 factorial structure of the subunit treatments: diets including high available phosphorus/low phytate corn (HAPC) and phytase (PHYT). Male broilers (1,760 per flock) were grown to 42 d having starter diets with 0.45% available P and grower diets with 0.35% available P. In the first trial, total litter P (tP) was greatest for the yellow dent corn (YDC) diet (12 g/kg) and least for the HAPC and PHYT combination (H&P) diet (6.9 g/kg) with the individual PHYT and HAPC diets falling in between at 9.1 g/kg and 9.4 g/kg tP. Also in the first trial, the litter water-soluble P (wP) was highest for PHYT (2.8 g/kg), least for the HAPC and H&P diets (1.5 g/kg) with the YDC diet falling between (2.2 g/kg). Alum was added to the litter after the first experiment. In the second and third experiments, alum inclusion significantly reduced the wP when compared with the treatments with no alum. In the third trial, the least wP was present in the alum-HAPC treatment. Phytase, YDC, and HAPC diets with no alum litter treatment generated the most wP. Since these diets appear to have little or no difference with respect to quantity of wP, this work suggests that form of litter P generated by alternative diets should be considered as criteria when attempting to reduce P in broiler litter applied to land.

  16. Litter box preference in domestic cats: covered versus uncovered.

    PubMed

    Grigg, Emma K; Pick, Lindsay; Nibblett, Belle

    2013-04-01

    Feline inappropriate elimination (periuria and/or perichezia) remains a very common behavioral complaint of cat owners. Treatment recommendations often include improving the attractiveness of the litter boxes available to the cat. One frequent recommendation is to avoid covered litter boxes, although this has not previously been tested experimentally. The goal of this study was to assess whether, all else being equal, cats preferentially used uncovered litter boxes over covered litter boxes. Twenty-eight cats were enrolled in the study and offered the choice of a covered or uncovered box. Waste was scooped daily from each box, and the weight of waste in the different box styles was compared and evaluated using paired t-tests and χ(2) analyses. Overall, there was no significant difference between use of the two box styles. Eight individual cats did exhibit a preference (four for covered, four for uncovered), but individual preference results are not evenly distributed, with more cats than expected showing no preference between litter box types. We postulate that, if boxes are kept sufficiently clean (ie, once daily minimum cleaning), most cats will not show a preference for either box type. The observation that a minority of cats in the study exhibited a preference supports the recommendation of providing individual cats with a 'cafeteria' of litter box styles, including a covered box, to determine whether such a preference exists. These findings add to existing literature on the topic of feline inappropriate elimination and provide additional information for clinicians recommending treatment options for cats exhibiting this behavior.

  17. Demonstration of a Small Modular BioPower System Using Poultry Litter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    John P. Reardon; Art Lilley; Jim Wimberly

    2002-05-22

    The purpose of this project was to assess poultry grower residue, or litter (manure plus absorbent biomass), as a fuel source for Community Power Corporation's small modular biopower system (SMB). A second objective was to assess the poultry industry to identify potential ''on-site'' applications of the SMB system using poultry litter residue as a fuel source, and to adapt CPC's existing SMB to generate electricity and heat from the poultry litter biomass fuel. Bench-scale testing and pilot testing were used to gain design information for the SMB retrofit. System design approach for the Phase II application of the SMB wasmore » the goal of Phase I testing. Cost estimates for an onsite poultry litter SMB were prepared. Finally, a market estimate was prepared for implementation of the on-farm SMB using poultry litter.« less

  18. Impact of fresh or used litter on the posthatch immune system of commercial broilers.

    PubMed

    Lee, K W; Lillehoj, H S; Lee, S H; Jang, S I; Ritter, G Donald; Bautista, D A; Lillehoj, E P

    2011-12-01

    This study was carried out to investigate the effects of exposure of growing broiler chickens of commercial origin to used poultry litter on intestinal and systemic immune responses. The litter types evaluated were fresh wood shavings or used litter obtained from commercial poultry farms with or without a history of gangrenous dermatitis (GD). Immune parameters measured were serum nitric oxide (NO) levels, serum antibody titers against Eimeria or Clostridium perfringens, mitogen-induced spleen cell proliferation, and intestinal intraepithelial lymphocyte or splenic lymphocyte subpopulations. At 43 days posthatch, birds raised on used litter from a GD farm had higher serum NO levels and greater Eimeria or C. perfringens antibody levels compared with chickens raised on fresh litter or used, non-GD litter. Birds raised on non-GD and GD used litter had greater spleen cell mitogenic responses compared with chickens raised on fresh litter. Finally, spleen and intestinal lymphocyte subpopulations were increased or decreased depending on the litter type and the surface marker analyzed. Although it is likely that the presence of Eimeria oocysts and endemic viruses varies qualitatively and quantitatively between flocks and, by extension, varies between different used litter types, we believe that these data provide evidence that exposure of growing chicks to used poultry litter stimulates humoral and cell-mediated immune responses, presumably due to contact with contaminating enteric pathogens.

  19. Emergence of suspected type D botulism in ruminants in England and Wales (2001 to 2009), associated with exposure to broiler litter.

    PubMed

    Payne, J H; Hogg, R A; Otter, A; Roest, H I J; Livesey, C T

    2011-06-18

    Scanning surveillance by the Veterinary Laboratories Agency revealed the emergence of suspected botulism in ruminants in 2003, presented as flaccid paralysis. From 2003 to 2009, 168 cattle and 19 sheep incidents were recorded, with mortality between 5 and 80 per cent. All sheep incidents and 95 per cent of cattle incidents had proximity to broiler litter. From July 2006, the gut contents collected from 74 affected cattle and 10 affected sheep were tested for Clostridium botulinum toxins using mice bioassays and for organisms by culture. Type D toxin was identified in 32 per cent of cattle and 18 per cent of sheep samples. C botulinum type D organisms were identified in 40 per cent of cattle and 30 per cent of sheep samples, but broth from one sample reacted with C and D antisera. Type C botulism has previously been reported more commonly than type D in the UK and has been associated with the use of poultry litter as fertiliser, bedding or feed. The almost exclusive association with C botulinum type D toxins or organisms in the gut contents in this survey suggests a change in the source or epidemiology of botulism in the UK. The source of C botulinum type D was uncertain. Broilers may carry C botulinum type D in their gut flora subclinically. The emergence of a new type D strain, or changes in broiler husbandry and nutrition, medication and other enteric infections may have affected colonisation with C botulinum. Further investigation of poultry and farm environments for sources of type D awaits the development of tests for C botulinum toxins that do not require the use of mice.

  20. Bioaccumulation and biological effects of cigarette litter in marine worms

    PubMed Central

    Wright, Stephanie L.; Rowe, Darren; Reid, Malcolm J.; Thomas, Kevin V.; Galloway, Tamara S.

    2015-01-01

    Marine debris is a global environmental issue. Smoked cigarette filters are the predominant coastal litter item; 4.5 trillion are littered annually, presenting a source of bioplastic microfibres (cellulose acetate) and harmful toxicants to marine environments. Despite the human health risks associated with smoking, little is known of the hazards cigarette filters present to marine life. Here we studied the impacts of smoked cigarette filter toxicants and microfibres on the polychaete worm Hediste diversicolor (ragworm), a widespread inhabitant of coastal sediments. Ragworms exposed to smoked cigarette filter toxicants in seawater at concentrations 60 fold lower than those reported for urban run-off exhibited significantly longer burrowing times, >30% weight loss, and >2-fold increase in DNA damage compared to ragworms maintained in control conditions. In contrast, ragworms exposed to smoked cigarette filter microfibres in marine sediment showed no significant effects. Bioconcentration factors for nicotine were 500 fold higher from seawater than from sediment. Our results illustrate the vulnerability of organisms in the water column to smoking debris and associated toxicants, and highlight the risks posed by smoked cigarette filter debris to aquatic life. PMID:26369692

  1. Interrelations between the microbiotas in the litter and in the intestines of commercial broiler chickens.

    PubMed

    Cressman, Michael D; Yu, Zhongtang; Nelson, Michael C; Moeller, Steven J; Lilburn, Michael S; Zerby, Henry N

    2010-10-01

    The intestinal microbiota of broiler chickens and the microbiota in the litter have been well studied, but the interactions between these two microbiotas remain to be determined. Therefore, we examined their reciprocal effects by analyzing the intestinal microbiotas of broilers reared on fresh pine shavings versus reused litter, as well as the litter microbiota over a 6-week cycle. Composite ileal mucosal and cecal luminal samples from birds (n = 10) reared with both litter conditions (fresh versus reused) were collected at 7, 14, 21, and 42 days of age. Litter samples were also collected at days 7, 14, 21, and 42. The microbiotas were profiled and compared within sample types based on litter condition using PCR and denaturing gradient gel electrophoresis (PCR-DGGE). The microbiotas were further analyzed using 16S rRNA gene clone libraries constructed from microbiota DNA extracted from both chick intestinal and litter samples collected at day 7. Results showed significant reciprocal effects between the microbiotas present in the litter and those in the intestines of broilers. Fresh litter had more environmental bacteria, while reused litter contained more bacteria of intestinal origin. Lactobacillus spp. dominated the ileal mucosal microbiota of fresh-litter chicks, while a group of bacteria yet to be classified within Clostridiales dominated in the ileal mucosal microbiota in the reused-litter chicks. The Litter condition (fresh versus reused) seemed to have a more profound impact on the ileal microbiota than on the cecal microbiota. The data suggest that the influence of fresh litter on ileal microbiota decreased as broilers grew, compared with temporal changes observed under reused-litter rearing conditions.

  2. Legacy phosphorus in calcareous soils: effects of long-term poultry litter application

    USDA-ARS?s Scientific Manuscript database

    Sequential fractionation techniques, coupled with phosphatase hydrolysis, have allowed for greater understanding of manure/litter effects on soil P distribution. We evaluated the effect of long-term (greater than 10 years) poultry litter (broiler and turkey litter) application at annual rates of 4.5...

  3. Composting and gypsum amendment of broiler litter to reduce nutrient leaching loss

    USDA-ARS?s Scientific Manuscript database

    Relative to fresh broiler litter, little is known about the dynamics of composted litter derived-nutrient in the ecosystem. In this study, the potential leaching losses of nutrients from compost relative to fresh broiler litter along with flue gas desulfurization (FGD gypsum), as a nutrient immobil...

  4. [Contribution of soil fauna to the mass loss of Betula albosinensis leaf litter at early decomposition stage of subalpine forest litter in western Sichuan].

    PubMed

    Xia, Lei; Wu, Fu-Zhong; Yang, Wan-Qin; Tan, Bo

    2012-02-01

    In order to quantify the contribution of soil fauna to the decomposition of birch (Betula albosinensis) leaf litter in subalpine forests in western Sichuan of Southwest China during freeze-thaw season, a field experiment with different mesh sizes (0.02, 0.125, 1 and 3 mm) of litterbags was conducted in a representative birch-fir (Abies faxoniana) forest to investigate the mass loss rate of the birch leaf litter from 26 October, 2010 to 18 April, 2011, and the contributions of micro-, meso- and macro-fauna to the decomposition of the leaf litter. Over the freeze-thaw season, 11.8%, 13.2%, 15.4% and 19.5% of the mass loss were detected in the litterbags with 0.02, 0. 125, 1 and 3 mm mesh sizes, respectively. The total contribution of soil fauna to the litter decomposition accounted for 39.5% of the mass loss, and the taxa and individual relative density of the soil fauna in the litterbags had the similar variation trend with that of the mass loss rate. The contribution rate of soil fauna to the leaf litter mass loss showed the order of micro- < meso- < macro-fauna, with the highest contribution of micro-fauna (7.9%), meso-fauna (11.9%), and macro-fauna (22.7%) at the onset of freezing stage, deeply frozen stage, and thawing stage, respectively. The results demonstrated that soil fauna played an important role in the litter decomposition in subalpine forests of western Sichuan during freeze-thaw season.

  5. Predicting climate change impacts on polar bear litter size.

    PubMed

    Molnár, Péter K; Derocher, Andrew E; Klanjscek, Tin; Lewis, Mark A

    2011-02-08

    Predicting the ecological impacts of climate warming is critical for species conservation. Incorporating future warming into population models, however, is challenging because reproduction and survival cannot be measured for yet unobserved environmental conditions. In this study, we use mechanistic energy budget models and data obtainable under current conditions to predict polar bear litter size under future conditions. In western Hudson Bay, we predict climate warming-induced litter size declines that jeopardize population viability: ∼28% of pregnant females failed to reproduce for energetic reasons during the early 1990s, but 40-73% could fail if spring sea ice break-up occurs 1 month earlier than during the 1990s, and 55-100% if break-up occurs 2 months earlier. Simultaneously, mean litter size would decrease by 22-67% and 44-100%, respectively. The expected timeline for these declines varies with climate-model-specific sea ice predictions. Similar litter size declines may occur in over one-third of the global polar bear population.

  6. Biotic and abiotic variables influencing plant litter breakdown in streams: a global study.

    PubMed

    Boyero, Luz; Pearson, Richard G; Hui, Cang; Gessner, Mark O; Pérez, Javier; Alexandrou, Markos A; Graça, Manuel A S; Cardinale, Bradley J; Albariño, Ricardo J; Arunachalam, Muthukumarasamy; Barmuta, Leon A; Boulton, Andrew J; Bruder, Andreas; Callisto, Marcos; Chauvet, Eric; Death, Russell G; Dudgeon, David; Encalada, Andrea C; Ferreira, Verónica; Figueroa, Ricardo; Flecker, Alexander S; Gonçalves, José F; Helson, Julie; Iwata, Tomoya; Jinggut, Tajang; Mathooko, Jude; Mathuriau, Catherine; M'Erimba, Charles; Moretti, Marcelo S; Pringle, Catherine M; Ramírez, Alonso; Ratnarajah, Lavenia; Rincon, José; Yule, Catherine M

    2016-04-27

    Plant litter breakdown is a key ecological process in terrestrial and freshwater ecosystems. Streams and rivers, in particular, contribute substantially to global carbon fluxes. However, there is little information available on the relative roles of different drivers of plant litter breakdown in fresh waters, particularly at large scales. We present a global-scale study of litter breakdown in streams to compare the roles of biotic, climatic and other environmental factors on breakdown rates. We conducted an experiment in 24 streams encompassing latitudes from 47.8° N to 42.8° S, using litter mixtures of local species differing in quality and phylogenetic diversity (PD), and alder (Alnus glutinosa) to control for variation in litter traits. Our models revealed that breakdown of alder was driven by climate, with some influence of pH, whereas variation in breakdown of litter mixtures was explained mainly by litter quality and PD. Effects of litter quality and PD and stream pH were more positive at higher temperatures, indicating that different mechanisms may operate at different latitudes. These results reflect global variability caused by multiple factors, but unexplained variance points to the need for expanded global-scale comparisons. © 2016 The Author(s).

  7. Biotic and abiotic variables influencing plant litter breakdown in streams: a global study

    PubMed Central

    Pearson, Richard G.; Hui, Cang; Gessner, Mark O.; Pérez, Javier; Alexandrou, Markos A.; Graça, Manuel A. S.; Cardinale, Bradley J.; Albariño, Ricardo J.; Arunachalam, Muthukumarasamy; Barmuta, Leon A.; Boulton, Andrew J.; Bruder, Andreas; Callisto, Marcos; Chauvet, Eric; Death, Russell G.; Dudgeon, David; Encalada, Andrea C.; Ferreira, Verónica; Figueroa, Ricardo; Flecker, Alexander S.; Gonçalves, José F.; Helson, Julie; Iwata, Tomoya; Jinggut, Tajang; Mathooko, Jude; Mathuriau, Catherine; M'Erimba, Charles; Moretti, Marcelo S.; Pringle, Catherine M.; Ramírez, Alonso; Ratnarajah, Lavenia; Rincon, José; Yule, Catherine M.

    2016-01-01

    Plant litter breakdown is a key ecological process in terrestrial and freshwater ecosystems. Streams and rivers, in particular, contribute substantially to global carbon fluxes. However, there is little information available on the relative roles of different drivers of plant litter breakdown in fresh waters, particularly at large scales. We present a global-scale study of litter breakdown in streams to compare the roles of biotic, climatic and other environmental factors on breakdown rates. We conducted an experiment in 24 streams encompassing latitudes from 47.8° N to 42.8° S, using litter mixtures of local species differing in quality and phylogenetic diversity (PD), and alder (Alnus glutinosa) to control for variation in litter traits. Our models revealed that breakdown of alder was driven by climate, with some influence of pH, whereas variation in breakdown of litter mixtures was explained mainly by litter quality and PD. Effects of litter quality and PD and stream pH were more positive at higher temperatures, indicating that different mechanisms may operate at different latitudes. These results reflect global variability caused by multiple factors, but unexplained variance points to the need for expanded global-scale comparisons. PMID:27122551

  8. The relationships between microbiological attributes and soil and litter quality in pure and mixed stands of native tree species in southeastern Bahia, Brazil.

    PubMed

    Gama-Rodrigues, Emanuela F; Gama-Rodrigues, Antonio Carlos; Barros, Nairam F; Moço, Maria Kellen S

    2011-11-01

    This study was conducted to link soil and litter microbial biomass and activity with soil and litter quality in the surface layer for different pure and mixed stands of native tree species in southeastern Bahia, Brazil. The purpose of the study was to see how strongly the differences among species and stands affect the microbiological attributes of the soil and to identify how microbial processes can be influenced by soil and litter quality. Soil and litter samples were collected from six pure and mixed stands of six hardwood species (Peltogyne angustifolia, Centrolobium robustum, Arapatiella psilophylla, Sclerolobium chrysophyllum, Cordia trichotoma, Macrolobium latifolium) native to the southeastern region of Bahia, Brazil. In plantations of native tree species in humid tropical regions, the immobilization efficiency of C and N by soil microbial biomass was strongly related to the chemical quality of the litter and to the organic matter quality of the soil. According to the variables analyzed, the mixed stand was similar to the natural forest and dissimilar to the pure stands. Litter microbial biomass represented a greater sink of C and N than soil microbial biomass and is an important contributor of resources to tropical soils having low C and N availability.

  9. Ecological restoration of litter in mined areas

    NASA Astrophysics Data System (ADS)

    Teresinha Gonçalves Bizuti, Denise; Nino Diniz, Najara; Schweizer, Daniella; de Marchi Soares, Thaís; Casagrande, José Carlos; Henrique Santin Brancalion, Pedro

    2016-04-01

    The success of ecological restoration projects depends on going monitoring of key ecological variables to determine if a desired trajectory has been established and, in the case of mining sites, nutrient cycling recovery plays an utmost importance. This study aimed to quantify and compare the annual litter production in native forests, and in restoration sites established in bauxite mines. We collected samples in 6 native forest remnants and 6 year-old restoration sites every month for a period of one year, in the city of Poços de Caldas/MG, SE Brazil. 120 wire collectors were used (0,6x0,6) and suspended 30cm above the soil surface. The material was dried until constant weight, weighed and fractionated in leaves, branches and reproductive material. The average annual litter production was 2,6 Mg ha-1 in native forests and 2,1 in forest in restoration sites, differing statistically. Litter production was higher in the rainy season, especially in September. Among the litter components, the largest contributor to total production was the fraction leaves, with 55,4% of the total dry weight of material collected, followed by reproductive material which contributed 24,5% and branches, with 20%. We conclude that the young areas in restoration process already restored important part, but still below the production observed in native areas.

  10. Botulism outbreak associated with poultry litter consumption in three Brazilian cattle herds.

    PubMed

    Ortolani, E L; Brito, L A; Mori, C S; Schalch, U; Pacheco, J; Baldacci, L

    1997-04-01

    One hundred fifty-five of 201 cattle from 3 different farms showed clinical signs and died of botulism after eating the same batch of poultry litter contaminated with poultry and rodent carcasses. The cattle had access to poultry litter for only 1 d; afterwards it was removed from the diet. Death occurred over a period of 17 d after the poultry litter intake. The peak mortality was on day 4; 20 animals died within 10 d of the ingestion. The greater the intake of poultry litter, the higher the cattle mortality. Three steers which died on the first day had peracute effects while the remaining cattle showed classical signs. Twenty-five of the 46 surviving cattle had mild clinical signs, but recovered in a few days. Type C Clostridium botulinum toxin was found in extracts of the poultry litter, carcasses and cattle intestinal contents. Nutrient composition of the poultry litter was normal but pH was lower (6.9) than usual (7.5 to 9.3).

  11. Impacts of soil petroleum contamination on nutrient release during litter decomposition of Hippophae rhamnoides.

    PubMed

    Zhang, Xiaoxi; Liu, Zengwen; Luc, Nhu Trung; Yu, Qi; Liu, Xiaobo; Liang, Xiao

    2016-03-01

    Petroleum exploitation causes contamination of shrub lands close to oil wells. Soil petroleum contamination affects nutrient release during the litter decomposition of shrubs, which influences nutrient recycling and the maintenance of soil fertility. Hence, this contamination may reduce the long-term growth and stability of shrub communities and consequently, the effects of phytoremediation. Fresh foliar litter of Hippophae rhamnoides, a potential phytoremediating species, was collected for this study. The litter was placed in litterbags and then buried in different petroleum-polluted soil media (the petroleum concentrations were 15, 30, and 45 g kg(-1) dry soil, which were considered as slightly, moderately and seriously polluted soil, respectively) for a decomposition test. The impacts of petroleum contamination on the release of nutrients (including N, P, K, Cu, Zn, Fe, Mn, Ca and Mg) were assessed. The results showed that (1) after one year of decomposition, the release of all nutrients was accelerated in the slightly polluted soil. In the moderately polluted soil, P release was accelerated, while Cu, Zn and Mn release was inhibited. In the seriously polluted soil, Cu and Zn release was accelerated, while the release of the other nutrients was inhibited. (2) The effect of petroleum on nutrient release from litter differed in different periods during decomposition; this was mainly due to changes in soil microorganisms and enzymes under the stress of petroleum contamination. (3) To maintain the nutrient cycling and the soil fertility of shrub lands, H. rhamnoides is only suitable for phytoremediation of soils containing less than 30 g kg(-1) of petroleum.

  12. 49 CFR 520.5 - Guidelines for identifying major actions significantly affecting the environment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... significantly affecting the environment. 520.5 Section 520.5 Transportation Other Regulations Relating to... significantly affecting the environment. (a) General guidelines. The phrase, “major Federal actions significantly affecting the quality of the human environment,” as used in this part, shall be construed with a...

  13. Restoration of Tidal Flow to Impounded Salt Marsh Exerts Mixed Effect on Leaf Litter Decomposition

    NASA Astrophysics Data System (ADS)

    Henry, B. A.; Schade, J. D.; Foreman, K.

    2015-12-01

    Salt marsh impoundments (e.g. roads, levees) disconnect marshes from ocean tides, which impairs ecosystem services and often promotes invasive species. Numerous restoration projects now focus on removing impoundments. Leaf litter decomposition is a central process in salt marsh carbon and nutrient cycles, and this study investigated the extent to which marsh restoration alters litter decomposition rates. We considered three environmental factors that can potentially change during restoration: salinity, tidal regime, and dominant plant species. A one-month field experiment (Cape Cod, MA) measured decay of litter bags in impounded, restored, and natural marshes under ambient conditions. A two-week lab experiment measured litter decay in controlled incubations under experimental treatments for salinity (1ppt and 30 ppt), tidal regime (inundated and 12 hr wet-dry cycles), and plant species (native Spartina alterniflora and invasive Phragmites australis). S. alterniflora decomposed faster in situ than P. australis (14±1.0% mass loss versus 0.74±0.69%). Corroborating this difference in decomposition, S. alterniflora supported greater microbial respiration during lab incubation, measured as CO2 flux from leaf litter and biological oxygen demand of water containing leached organic matter (OM). However, nutrient analysis of plant tissue and leached OM show P. australis released more nitrogen than S. alterniflora. Low salinity treatments in both lab and field experiments decayed more rapidly than high salinity treatments, suggesting that salinity inhibited microbial activity. Manipulation of inundation regime did not affect decomposition. These findings suggest the reintroduction of tidal flow to an impounded salt marsh can have mixed effects; recolonization by the native cordgrass could supply labile OM to sediment and slow carbon sequestration, while an increase in salinity might inhibit decomposition and accelerate sequestration.

  14. Does Litter Impart A Detectable Chemical Signal on Soil DOC? DOC Fluorescence Signatures in Soils Undergoing Long-Term Litter Manipulations

    NASA Astrophysics Data System (ADS)

    Lajtha, K.; Strid, A.; Lee, B. S.

    2015-12-01

    Soil dissolved organic carbon (DOC) is a small but crucial part of the forest carbon cycle. Characterizing the relationship between organic matter inputs to soil and DOC chemistry is crucial to understanding the ultimate fate of root carbon, fallen wood and needles. Chemical differences in the DOC pool may help to explain whether fractions are sorbed to mineral surfaces and contribute to accumulation of soil organic carbon, respired as CO2, or exported. Soil solution DOC was sampled from the detrital input and removal treatment (DIRT) plots located in the H.J. Andrews Experimental Forest, OR to determine whether detrital inputs impart a detectable signal on DOC in mineral soil. Multiple types of fresh litter extracts, along with lysimeter and soil extracts from DIRT treatment plots were characterized using UV-Vis and fluorescence spectroscopy coupled with the Cory and McKnight (2005) parallel factor analysis (PARAFAC) model. Principal component analysis of 13 unique fluorophores distinguished using PARAFAC show that litter and soil extracts (needles, wood of decomposition Class 1, Class 3 and Class 5, O-horizon, and A-horizon) each have distinct fluorescence signatures. However, while litter-leached DOC chemistry varies by litter type, neither lysimeter-collected DOC or soil extracts show statistically significant differences in fluorescence signatures among treatments, even after 17 years of litter manipulations. The lack of observed differences among DIRT treatments suggests a "Soil Blender" hypothesis whereby both abiotic and biotic mechanisms effectively homogenize organic carbon constituents within the dissolved pool. The results of this work emphasize the ability of sorption and biodegradation to homogenize soil DOC and demonstrate that fluorescence can be an effective fingerprinting technique for soil DOC composition.

  15. Leaf litter dynamics and nitrous oxide emission in a Mediterranean riparian forest: implications for soil nitrogen dynamics.

    PubMed

    Bernal, S; Butturini, A; Nin, E; Sabater, F; Sabater, S

    2003-01-01

    Mediterranean riparian zones can experience severe drought periods that lead to low soil moisture content, which dramatically affects their performance as nitrate removal systems. In the Mediterranean riparian zone of this study, we determined that N2O emission was practically nil. To understand the role of forest floor processes in nitrogen retention of a Mediterranean riparian area, we studied leaf litter dynamics of two tree species, London planetree [Platanus x acerifolia (Aiton) Willd.] and alder [Alnus glutinosa (L.) Gaertn.], for two years, along with soil nitrogen mineralization rates. Annual leaf litter fall equaled 562.6 +/- 10.1 (standard error) g dry wt. m(-2), 68% of which was planetree and 32% of which was alder. The temporal distribution of litterfall showed a two-peak annual cycle, one occurring in midsummer, the other in autumn. Planetree provided the major input of organic nitrogen to the forest floor, and the amount of planetree leaves remaining on the forest floor was equivalent to approximately four years of stock. Leaf litter decomposition was three times higher for alder (decay coefficient [k] = 1.13 yr(-1)) than for planetree (k = 0.365 yr(-1)). Mineralization rates showed a seasonal pattern, with the maximum rate in summer (1.92 mg N kg(-1) d(-1)). Although the forest floor was an important sink for nitrogen due to planetree leaf accumulation, 7.5% of this leaf litter was scoured to the streambed by wind. This loss was irrelevant for alder leaves. Due to the litter quality, the forest floor of this Mediterranean riparian forest acts as a nitrogen sink.

  16. Amino compounds in poultry litter, litter-amended pasture soils and grass shoots

    USDA-ARS?s Scientific Manuscript database

    Organic N accounts for 95-98% of total soil N contents with amino compounds (ACs) as major ingredients. But relatively little is known about the effects of poultry litter (PL) application on soil AC pools and turnover. In this work, we determined 21 AC contents in 23 PL samples, 15 soil samples with...

  17. Effect of different types of litter material for rearing broilers.

    PubMed

    Swain, B K; Sundaram, R N

    2000-07-01

    1. Coir dust was evaluated as broiler litter in comparison with sawdust and rice husk using 135 commercial broilers. Forty-five broiler chicks were reared to 42 d on a 50 mm layer of each of these litters. 2. Birds reared on coir dust showed no difference in food consumption, body weight gain, food conversion efficiency production number and survivability in comparison to those reared on saw dust and rice husk. 3. It was concluded that coir dust is suitable as broiler litter when cheaply available.

  18. Artificial neural networks for modeling time series of beach litter in the southern North Sea.

    PubMed

    Schulz, Marcus; Matthies, Michael

    2014-07-01

    In European marine waters, existing monitoring programs of beach litter need to be improved concerning litter items used as indicators of pollution levels, efficiency, and effectiveness. In order to ease and focus future monitoring of beach litter on few important litter items, feed-forward neural networks consisting of three layers were developed to relate single litter items to general categories of marine litter. The neural networks developed were applied to seven beaches in the southern North Sea and modeled time series of five general categories of marine litter, such as litter from fishing, shipping, and tourism. Results of regression analyses show that general categories were predicted significantly moderately to well. Measured and modeled data were in the same order of magnitude, and minima and maxima overlapped well. Neural networks were found to be eligible tools to deliver reliable predictions of marine litter with low computational effort and little input of information. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Effects of two litter amendments on air NH3 levels in broiler closed-houses

    PubMed Central

    Atapattu, N. S. B. M; Lakmal, L. G. E.; Perera, P. W. A.

    2017-01-01

    Objective High NH3 emissions from poultry houses are reported to have negative impacts on health, welfare and safety of birds and humans, and on the environment. Objective of the present study was to determine the effects of two litter amendments on the NH3 levels in broiler closed houses under hot-humid conditions. Methods Giving a completely randomize design, nine closed houses, each housed 32,500 birds on paddy husk litter, were randomly allocated into two treatment (Mizuho; a bacterial culture mix and Rydall OE; an enzymatic biocatalyst) and control groups. NH3 levels were determined thrice a day (0600, 1200, and 1800 h), at three heights from the litter surface (30, 90, and 150 cm), at 20 predetermined locations of a house, from day 1 to 41. Results Rydall significantly reduced the NH3 level compared to control and Mizuho. NH3 levels at 30 cm were significantly higher than that of 90 and 150 cm. The NH3 levels at 30 cm height were higher than 25 ppm level from day 9, 11, and 13 in Mizuho, control, and Rydall groups, respectively to day 41. NH3 levels at 150 cm height were higher than maximum threshold limit of 50 ppm for human exposure from day 12, 14, and 15 in Mizuho, control, and Rydall groups, respectively to day 33. Being significantly different among each other, the NH3 level was highest and lowest at 0600 and 1800 h. Litter amendments had no significant effects on growth performance. Rydall significantly increased the litter N content on day 24. Conclusion It was concluded that the NH3 levels of closed house broiler production facilities under tropical condition are so high that both birds and workers are exposed to above recommended levels during many days of the growing period. Compared to microbial culture, the enzymatic biocatalyst was found to be more effective in reducing NH3 level. PMID:28423888

  20. Universal Distribution of Litter Decay Rates

    NASA Astrophysics Data System (ADS)

    Forney, D. C.; Rothman, D. H.

    2008-12-01

    Degradation of litter is the result of many physical, chemical and biological processes. The high variability of these processes likely accounts for the progressive slowdown of decay with litter age. This age dependence is commonly thought to result from the superposition of processes with different decay rates k. Here we assume an underlying continuous yet unknown distribution p(k) of decay rates [1]. To seek its form, we analyze the mass-time history of 70 LIDET [2] litter data sets obtained under widely varying conditions. We construct a regularized inversion procedure to find the best fitting distribution p(k) with the least degrees of freedom. We find that the resulting p(k) is universally consistent with a lognormal distribution, i.e.~a Gaussian distribution of log k, characterized by a dataset-dependent mean and variance of log k. This result is supported by a recurring observation that microbial populations on leaves are log-normally distributed [3]. Simple biological processes cause the frequent appearance of the log-normal distribution in ecology [4]. Environmental factors, such as soil nitrate, soil aggregate size, soil hydraulic conductivity, total soil nitrogen, soil denitrification, soil respiration have been all observed to be log-normally distributed [5]. Litter degradation rates depend on many coupled, multiplicative factors, which provides a fundamental basis for the lognormal distribution. Using this insight, we systematically estimated the mean and variance of log k for 512 data sets from the LIDET study. We find the mean strongly correlates with temperature and precipitation, while the variance appears to be uncorrelated with main environmental factors and is thus likely more correlated with chemical composition and/or ecology. Results indicate the possibility that the distribution in rates reflects, at least in part, the distribution of microbial niches. [1] B. P. Boudreau, B.~R. Ruddick, American Journal of Science,291, 507, (1991). [2] M

  1. Isotopic Discrimination During Leaf Litter Decomposition

    NASA Astrophysics Data System (ADS)

    Ngao, J.; Rubino, M.

    2006-12-01

    Methods involving stable isotopes have been successfully applied since decades in various research fields. Tracing 13C natural abundance in ecosystem compartments greatly enhanced the understanding of the C fluxes in the plant-soil-atmosphere C exchanges when compartments present different C isotopic signatures (i.e. atmospheric CO2 vs photosynthetic leaves, C3 vs C4; etc.). However, the assumption that no isotopic discrimination occurs during respiration is commonly made in numbers of C isotope-based ecological studies. Furthermore, verifications of such assumption are sparse and not enough reliable. The aim of our study is to assess the potential isotopic discrimination that may occur during litter decomposition. Leaf litter from an Arbutus unedo (L.) stand (Tolfa, Italy) was incubated in 1L jars, under constant laboratory conditions (i.e. 25 ° C and 135% WC). During the entire incubation period, gravimetric mass loss, litter respiration rates and the isotopic composition of respired CO2 are monitored at regular intervals. Data from 7 months of incubation will be presented and discussed. After two months, the litter mass loss averaged 16% of initial dry mass. During the same time-period, the respiration rate decreased significantly by 58% of the initial respiration rate. Isotopic compositions of respired CO2 ranged between -27.95‰ and - 25.69‰. Mean values did not differ significantly among the sampling days, in spite of an apparent enrichment in 13C of respired CO2 with time. The significance of these isotopic enrichment will be determined at a longer time scale. They may reveal both/either a direct microbial discrimination during respiration processes and/or a use of different litter compounds as C source along time. Further chemical and compound-specific isotopic analysis of dry matter will be performed in order to clarify these hypotheses. This work is part of the "ALICE" project, funded by the European Union's Marie Curie Fellowship Actions that aims to

  2. Tracing C Fluxes From Leaf Litter To Microbial Respired CO2 And Specific Soil Compounds

    NASA Astrophysics Data System (ADS)

    Rubino, M.; Lubritto, C.; D'Onofrio, A.; Gleixner, G.; Terrasi, F.; Cotrufo, F. M.

    2004-12-01

    Despite litter decomposition is one of the major process controlling soil C stores and nutrient cycling, yet C dynamics during litter decay are poorly understood and quantified. Here we report the results of a laboratory experiment where 13C depleted leaf litter was incubated on a 13C enriched soil with the aims to: i) partition the C loss during litter decay into microbial respired-CO2 and C input into the soil; ii) identify the soil compounds where litter derived C is retained; iii) assess whether litter quality is a determinant of both the above processes. Three 13C-depleted leaf litter(delta13C ca. -43), differing in their degradability, were incubated on C4 soil (delta13C ca. -18) under laboratory controlled conditions for 8 months, with litter respiration and delta13C-CO2 being measured at regular intervals. At harvest, Compound Specific Isotope Analyses was performed on soil and litter samples in order to follow the fate of litter-derived C compounds in the various pools of SOMƒn The delta13C of soils carbohydrates, alkanes and Phospho Lipids Fatty Acids (PLFA) were measured, and the mixing model approach used to quantify the contribution of litter derived C to the specific compounds.

  3. Leaf litter production of mahogany along street and campus forest of Universitas Negeri Semarang, Indonesia

    NASA Astrophysics Data System (ADS)

    Martin, F. P.; Abdullah, M.; Solichin; Hadiyanti, L. N.; Widianingrum, K.

    2018-03-01

    The leaf litter of trees along the existing streets on campus UNNES if not managed properly will be scattered and become garbage. Leaf litter Production in UNNES campus is not known for certain. UNNES does not own mapping of leaf litter Production of dominant tree species on campus. This cause leaf waste management is not optimal yet. There is still a lot of leaf litter that is discharged (not processed) because it exceeds the capacity of the fertilizer production equipment in the compost house. Aims of this study were to examine leaf litter production of dominant trees in Universitas Negeri Semarang and evaluate the relationship between leaf litter and average rainfall. Purposive sampling method placed pouches of nylon gauze measuring 1 × 1 mm2 as litter trap container with size 1 x l m2 (10 points mounted along street and campus forest). Litter trap mounted at the height of 50 cm above ground level. Leaf litter will be taken once a week for three months to observe the litter production. The litter was then dried by the oven at 70 ° C for 48 hours to obtain constant dry weight. Based on the results of the research, it was known that Mahogany tree in UNNES campus area has the potential to produce the litter of about 10 ton/ha / 3months in campus forest area and 2.5 ton/ha / 3months along campus street. There is a significant relationship between litter production of Mahogany leaves and precipitation during August - October 2017.

  4. Characterization of forest litter horizons through full-wave inversion of ground-penetrating radar data

    NASA Astrophysics Data System (ADS)

    André, Frédéric; Jonard, Mathieu; Jonard, François; Lambot, Sébastien

    2015-04-01

    Decomposing litter accumulated at the soil surface in forest ecosystems play a major role in a series of ecosystem processes (soil carbon sequestration, nutrient release through decomposition, water retention, buffering of soil temperature variations, tree regeneration, population dynamics of ground vegetation and soil fauna, ...). Besides, the presence of litter is acknowledged to influence remote sensing radar data over forested areas and accurate quantification of litter radiative properties is essential for proper processing of these data. In these respects, ground-penetrating radar (GPR) presents particular interests, potentially allowing for fast and non-invasive characterization of organic layers with fine spatial and/or temporal resolutions as well as for providing detailed information on litter electrical properties which are required for modeling either active or passive microwave remote sensing data. We designed an experiment in order to analyze the backscattering from forest litter horizons and to investigate the potentialities of GPR for retrieving the physical properties of these horizons. For that purpose, we used an ultrawide band radar system connected to a transmitting and receiving horn antenna. The GPR data were processed resorting to full-wave inversion of the signal, through which antenna effects are accounted for. In a first step, GPR data were acquired over artificially reconstructed layers of three different beech litter types (i.e., (i) recently fallen litter with easily discernible plant organs (OL layer), (ii) fragmented litter in partial decomposition without entire plant organs (OF layer) and (iii) combination of OL and OF litter layers) and considering in each case a range of layer thicknesses. In a second step, so as to validate the adopted methodology in real natural conditions, GPR measurements were performed in situ along a transect crossing a wide range of litter properties in terms of thickness and composition through stands of

  5. Poultry litter-based activated carbon for removing heavy metal ions in water.

    PubMed

    Guo, Mingxin; Qiu, Guannan; Song, Weiping

    2010-02-01

    Utilization of poultry litter as a precursor material to manufacture activated carbon for treating heavy metal-contaminated water is a value-added strategy for recycling the organic waste. Batch adsorption experiments were conducted to investigate kinetics, isotherms, and capacity of poultry litter-based activated carbon for removing heavy metal ions in water. It was revealed that poultry litter-based activated carbon possessed significantly higher adsorption affinity and capacity for heavy metals than commercial activated carbons derived from bituminous coal and coconut shell. Adsorption of metal ions onto poultry litter-based carbon was rapid and followed Sigmoidal Chapman patterns as a function of contact time. Adsorption isotherms could be described by different models such as Langmuir and Freundlich equations, depending on the metal species and the coexistence of other metal ions. Potentially 404 mmol of Cu2+, 945 mmol of Pb2+, 236 mmol of Zn2+, and 250-300 mmol of Cd2+ would be adsorbed per kg of poultry litter-derived activated carbon. Releases of nutrients and metal ions from litter-derived carbon did not pose secondary water contamination risks. The study suggests that poultry litter can be utilized as a precursor material for economically manufacturing granular activated carbon that is to be used in wastewater treatment for removing heavy metals.

  6. Low dissolved organic carbon input from fresh litter to deep mineral soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Froeberg, Mats J; Jardine, Philip M; Hanson, Paul J

    2007-01-01

    Dissolved organic carbon (DOC) leached from recent litter in the forest floor has been suggested to be an important source of C to the mineral soil of forest ecosystems. In order to determine the rate at which this flux of C occurs we have taken advantage of a local release of 14C at Oak Ridge National Laboratory Reservation, USA (latitude N 35 58'; longitude W 84 16'). Eight replicate 7x7 m plots were estab lished at four field sites on the reservation in an upland oak forest setting. Half of the plots were provided with 14C-enriched litter (∆14C ≈1000 ),more » and the other half with near-background litter (∆14C ≈220 ) over multiple years. Differences in the labeled leaf litter were used to quantify the movement of litter derived DOC through the soil profile. Soil solutions were collected over several years with tension lysimeters at 15 and 70 cm depth and measured for DOC concentration and 14C abundance. The net amount of DOC retained between 15 and 70 cm was 1.5-6 g m-2 y-1. There were significant effects of the litter additions on the 14C abundance in the DOC, but the net transport of 14C from the added litter was small. The difference in ∆14C between the treatments with enriched and near-background litter was only about 130 at both depths, which is small compared with the difference in Δ14C in the added litter. The primary source of DOC within the mineral soil must therefore have been either the Oe/Oa horizon or the organic matter in the mineral soil. Over a 2-year time frame, leaching of DOC from recent litter did not have a major impact on the C stock in the mineral soil below 15 cm in this ecosystem.« less

  7. Low densities of drifting litter in the African sector of the Southern Ocean.

    PubMed

    Ryan, Peter G; Musker, Seth; Rink, Ariella

    2014-12-15

    Only 52 litter items (>1cm diameter) were observed in 10,467 km of at-sea transects in the African sector of the Southern Ocean. Litter density north of the Subtropical Front (0.58 items km(-2)) was less than in the adjacent South Atlantic Ocean (1-6 items km(-2)), but has increased compared to the mid-1980s. Litter density south of the Subtropical Front was an order of magnitude less than in temperate waters (0.032 items km(-2)). There was no difference in litter density between sub-Antarctic and Antarctic waters either side of the Antarctic Polar Front. Most litter was made of plastic (96%). Fishery-related debris comprised a greater proportion of litter south of the Subtropical Front (33%) than in temperate waters (13%), where packaging dominated litter items (68%). The results confirm that the Southern Ocean is the least polluted ocean in terms of drifting debris and suggest that most debris comes from local sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Distribution of Slash and Litter After Wet- and Dry-Site Harvesting of Loblolly Pine Plantations

    Treesearch

    Mark H. Eisenbies; James A. Burger; Yi-Jun Xu; Steve Patterson

    2002-01-01

    Displacement of logging slash and forest floor litter in the process of harvesting can interfere with forest nutrient cycling and can modify soil climate in ways that could affect regeneration success and forest productivity. The objective of this study was to assess a visual method for estimating organic matter and slash biomass residues following a typical feller-...

  9. SOA formation potential of emissions from soil and leaf litter.

    PubMed

    Faiola, Celia L; Vanderschelden, Graham S; Wen, Miao; Elloy, Farah C; Cobos, Douglas R; Watts, Richard J; Jobson, B Thomas; Vanreken, Timothy M

    2014-01-21

    Soil and leaf litter are significant global sources of small oxidized volatile organic compounds, VOCs (e.g., methanol and acetaldehyde). They may also be significant sources of larger VOCs that could act as precursors to secondary organic aerosol (SOA) formation. To investigate this, soil and leaf litter samples were collected from the University of Idaho Experimental Forest and transported to the laboratory. There, the VOC emissions were characterized and used to drive SOA formation via dark, ozone-initiated reactions. Monoterpenes dominated the emission profile with emission rates as high as 228 μg-C m(-2) h(-1). The composition of the SOA produced was similar to biogenic SOA formed from oxidation of ponderosa pine emissions and α-pinene. Measured soil and litter monoterpene emission rates were compared with modeled canopy emissions. Results suggest surface soil and litter monoterpene emissions could range from 12 to 136% of canopy emissions in spring and fall. Thus, emissions from leaf litter may potentially extend the biogenic emissions season, contributing to significant organic aerosol formation in the spring and fall when reduced solar radiation and temperatures reduce emissions from living vegetation.

  10. SOA formation potential of emissions from soil and leaf litter

    DOE PAGES

    Faiola, Celia L.; VanderSchelden, Graham S.; Wen, Miao; ...

    2013-12-13

    Soil and leaf litter are significant global sources of small oxidized volatile organic compounds, VOCs (e.g., methanol and acetaldehyde). They may also be significant sources of larger VOCs that could act as precursors to secondary organic aerosol (SOA) formation. To investigate this, soil and leaf litter samples were collected from the University of Idaho Experimental Forest and transported to the laboratory. There, the VOC emissions were characterized and used to drive SOA formation via dark, ozone-initiated reactions. Monoterpenes dominated the emission profile with emission rates as high as 228 μg-C m –2 h –1. The composition of the SOA producedmore » was similar to biogenic SOA formed from oxidation of ponderosa pine emissions and α-pinene. Measured soil and litter monoterpene emission rates were compared with modeled canopy emissions. Results suggest surface soil and litter monoterpene emissions could range from 12 to 136% of canopy emissions in spring and fall. Furthermore, emissions from leaf litter may potentially extend the biogenic emissions season, contributing to significant organic aerosol formation in the spring and fall when reduced solar radiation and temperatures reduce emissions from living vegetation.« less

  11. Poultry litter application to loblolly pine forests: growth and nutrient containment.

    PubMed

    Friend, Alexander L; Roberts, Scott D; Schoenholtz, Stephen H; Mobley, Juanita A; Gerard, Patrick D

    2006-01-01

    Forestland application of poultry manure offers an alternative to the conventional practice of pastureland application. Before such a practice is considered viable, however, it must be demonstrated that the forest ecosystem is capable of absorbing the nutrients contained in poultry manure, especially nitrogen (N) and phosphorus (P). From the forestry perspective, it must also be demonstrated that tree growth is not diminished. We investigated these questions using loblolly pine (Pinus taeda L.) stands growing in central Mississippi in an area of high poultry production. Stockpiled broiler litter was applied to newly thinned, 8-yr-old stands at 0, 4.6, and 18.6 dry Mg ha-1, supplying 0, 200, and 800 kg N ha-1 and 0, 92, and 370 kg P ha-1, respectively. Levels of nitrate in soil water, monitored at a 50-cm depth with porous cup tension lysimeters, exceeded 10 mg N L-1 during the first two years after application in the 18.6 Mg ha-1 rate but only on two occasions in the first year for the lower rate of application. Phosphate was largely absent from lysimeter water in all treatments. Other macronutrients (K, Ca, Mg, S) were elevated in lysimeter water in proportion to litter application rates. Soil extractable nitrate showed similar trends to lysimeter water, with substantial elevation during the first year following application for the 18.6 Mg ha-1 rate. Mehlich III-extractable phosphate peaked in excess of 100 microg P g-1 soil during the third year of the study for the 18.6 Mg ha-1 rate. The 4.6 Mg ha-1 rate did not affect extractable soil P. Tree growth was increased by the poultry litter. Total stem cross-sectional area, or basal area, was approximately 20% greater after 2 yr for both rates of litter application. Overall, the nutrients supplied by the 4.6 Mg ha-1 rate were contained by the pine forest and resulted in favorable increases in tree growth. The higher rate, by contrast, did pose some risk to water quality through the mobilization of nitrate. These

  12. Understanding litter decomposition in semiarid ecosystems: linking leaf traits, UV exposure and rainfall variability

    PubMed Central

    Gaxiola, Aurora; Armesto, Juan J.

    2015-01-01

    Differences in litter quality, microbial activity or abiotic conditions cannot fully account for the variability in decomposition rates observed in semiarid ecosystems. Here we tested the role of variation in litter quality, water supply, and UV radiation as drivers of litter decomposition in arid lands. And show that carry-over effects of litter photodegradation during dry periods can regulate decomposition during subsequent wet periods. We present data from a two-phase experiment, where we first exposed litter from a drought-deciduous and an evergreen shrub to natural UV levels during five, rainless summer months and, subsequently, in the laboratory, we assessed the carry-over effects of photodegradation on biomass loss under different irrigation treatments representing the observed range of local rainfall variation among years (15–240 mm). Photodegradation of litter in the field produced average carbon losses of 12%, but deciduous Proustia pungens lost >25%, while evergreen Porlieria chilensis less than 5%. Natural exposure to UV significantly reduced carbon-to-nitrogen and lignin:N ratios in Proustia litter but not in Porlieria. During the subsequent wet phase, remaining litter biomass was lower in Proustia than in Porlieria. Indeed UV exposure increased litter decomposition of Proustia under low and medium rainfall treatments, whereas no carry-over effects were detected under high rainfall treatment. Consequently, for deciduous Proustia carry-over effects of UV exposure were negligible under high irrigation. Litter decomposition of the evergreen Porlieria depended solely on levels of rainfall that promote microbial decomposers. Our two-phase experiment revealed that both the carry-over effects of photodegradation and litter quality, modulated by inter-annual variability in rainfall, can explain the marked differences in decomposition rates and the frequent decoupling between rainfall and litter decomposition observed in semiarid ecosystems. PMID:25852705

  13. Understanding litter decomposition in semiarid ecosystems: linking leaf traits, UV exposure and rainfall variability.

    PubMed

    Gaxiola, Aurora; Armesto, Juan J

    2015-01-01

    Differences in litter quality, microbial activity or abiotic conditions cannot fully account for the variability in decomposition rates observed in semiarid ecosystems. Here we tested the role of variation in litter quality, water supply, and UV radiation as drivers of litter decomposition in arid lands. And show that carry-over effects of litter photodegradation during dry periods can regulate decomposition during subsequent wet periods. We present data from a two-phase experiment, where we first exposed litter from a drought-deciduous and an evergreen shrub to natural UV levels during five, rainless summer months and, subsequently, in the laboratory, we assessed the carry-over effects of photodegradation on biomass loss under different irrigation treatments representing the observed range of local rainfall variation among years (15-240 mm). Photodegradation of litter in the field produced average carbon losses of 12%, but deciduous Proustia pungens lost >25%, while evergreen Porlieria chilensis less than 5%. Natural exposure to UV significantly reduced carbon-to-nitrogen and lignin:N ratios in Proustia litter but not in Porlieria. During the subsequent wet phase, remaining litter biomass was lower in Proustia than in Porlieria. Indeed UV exposure increased litter decomposition of Proustia under low and medium rainfall treatments, whereas no carry-over effects were detected under high rainfall treatment. Consequently, for deciduous Proustia carry-over effects of UV exposure were negligible under high irrigation. Litter decomposition of the evergreen Porlieria depended solely on levels of rainfall that promote microbial decomposers. Our two-phase experiment revealed that both the carry-over effects of photodegradation and litter quality, modulated by inter-annual variability in rainfall, can explain the marked differences in decomposition rates and the frequent decoupling between rainfall and litter decomposition observed in semiarid ecosystems.

  14. ESTIMATING THE BREAKDOWN AND ACCUMULATION OF EMERGENT MACROPHYTE LITTER: A MASS-BALANCE APPROACH

    EPA Science Inventory

    Litter accumulation within emergent macrophyte marshes may significantly influence abiotic conditions and biota but litter is rarely considered in emergent macrophyte studies. Litter is defined here as the standing and fallen dead plant material that can be collected using harv...

  15. Influence of different forest system management practices on leaf litter decomposition rates, nutrient dynamics and the activity of ligninolytic enzymes: a case study from central European forests.

    PubMed

    Purahong, Witoon; Kapturska, Danuta; Pecyna, Marek J; Schulz, Elke; Schloter, Michael; Buscot, François; Hofrichter, Martin; Krüger, Dirk

    2014-01-01

    Leaf litter decomposition is the key ecological process that determines the sustainability of managed forest ecosystems, however very few studies hitherto have investigated this process with respect to silvicultural management practices. The aims of the present study were to investigate the effects of forest management practices on leaf litter decomposition rates, nutrient dynamics (C, N, Mg, K, Ca, P) and the activity of ligninolytic enzymes. We approached these questions using a 473 day long litterbag experiment. We found that age-class beech and spruce forests (high forest management intensity) had significantly higher decomposition rates and nutrient release (most nutrients) than unmanaged deciduous forest reserves (P<0.05). The site with near-to-nature forest management (low forest management intensity) exhibited no significant differences in litter decomposition rate, C release, lignin decomposition, and C/N, lignin/N and ligninolytic enzyme patterns compared to the unmanaged deciduous forest reserves, but most nutrient dynamics examined in this study were significantly faster under such near-to-nature forest management practices. Analyzing the activities of ligninolytic enzymes provided evidence that different forest system management practices affect litter decomposition by changing microbial enzyme activities, at least over the investigated time frame of 473 days (laccase, P<0.0001; manganese peroxidase (MnP), P = 0.0260). Our results also indicate that lignin decomposition is the rate limiting step in leaf litter decomposition and that MnP is one of the key oxidative enzymes of litter degradation. We demonstrate here that forest system management practices can significantly affect important ecological processes and services such as decomposition and nutrient cycling.

  16. The Influence of Plant Litter on Soil Water Repellency: Insight from 13C NMR Spectroscopy.

    PubMed

    Cesarano, Gaspare; Incerti, Guido; Bonanomi, Giuliano

    2016-01-01

    Soil water repellency (SWR, i.e. reduced affinity for water owing to the presence of organic hydrophobic coatings on soil particles) has relevant hydrological implications because low rates of infiltration enhance water runoff, and untargeted diffusion of fertilizers and pesticides. Previous studies investigated the occurrence of SWR in ecosystems with different vegetation cover but did not clarify its relationships with litter biochemical quality. Here, we investigated the capability of different plant litter types to induce SWR by using fresh and decomposed leaf materials from 12 species, to amend a model sandy soil over a year-long microcosm experiment. Water repellency, measured by the Molarity of an Ethanol Droplet (MED) test, was tested for the effects of litter species and age, and compared with litter quality assessed by 13C-CPMAS NMR in solid state and elemental chemical parameters. All litter types were highly water repellent, with MED values of 18% or higher. In contrast, when litter was incorporated into the soil, only undecomposed materials induced SWR, but with a large variability of onset and peak dynamics among litter types. Surprisingly, SWR induced by litter addition was unrelated to the aliphatic fraction of litter. In contrast, lignin-poor but labile C-rich litter, as defined by O-alkyl C and N-alkyl and methoxyl C of 13C-CPMAS NMR spectral regions, respectively, induced a stronger SWR. This study suggests that biochemical quality of plant litter is a major controlling factor of SWR and, by defining litter quality with 13C-CPMAS NMR, our results provide a significant novel contribution towards a full understanding of the relationships between plant litter biochemistry and SWR.

  17. Burning management in the tallgrass prairie affects root decomposition, soil food web structure and carbon flow

    NASA Astrophysics Data System (ADS)

    Shaw, E. A.; Denef, K.; Milano de Tomasel, C.; Cotrufo, M. F.; Wall, D. H.

    2015-09-01

    Root litter decomposition is a major component of carbon (C) cycling in grasslands, where it provides energy and nutrients for soil microbes and fauna. This is especially important in grasslands where fire is a common management practice and removes aboveground litter accumulation. In this study, we investigated whether fire affects root decomposition and C flow through the belowground food web. In a greenhouse experiment, we applied 13C-enriched big bluestem (Andropogon gerardii) root litter to intact tallgrass prairie soil cores collected from annually burned (AB) and infrequently burned (IB) treatments at the Konza Prairie Long Term Ecological Research (LTER) site. Incorporation of 13C into microbial phospholipid fatty acids and nematode trophic groups was measured on six occasions during a 180-day decomposition study to determine how C was translocated through the soil food web. Results showed significantly different soil communities between treatments and higher microbial abundance for IB. Root decomposition occurred rapidly and was significantly greater for AB. Microbes and their nematode consumers immediately assimilated root litter C in both treatments. Root litter C was preferentially incorporated in a few groups of microbes and nematodes, but depended on burn treatment: fungi, Gram-negative bacteria, Gram-positive bacteria, and fungivore nematodes for AB and only omnivore nematodes for IB. The overall microbial pool of root litter-derived C significantly increased over time but was not significantly different between burn treatments. The nematode pool of root litter-derived C also significantly increased over time, and was significantly higher for the AB treatment at 35 and 90 days after litter addition. In conclusion, the C flow from root litter to microbes to nematodes is not only measurable, but significant, indicating that higher nematode trophic levels are critical components of C flow during root decomposition which, in turn, is significantly

  18. Correlation between the morphogenetic types of litter and their properties in bog birch forests

    NASA Astrophysics Data System (ADS)

    Efremova, T. T.; Efremov, S. P.; Avrova, A. F.

    2010-08-01

    A formalized arrangement of morphogenetic types of litter according to the physicochemical parameters provided their significant grouping in three genetic associations. The litter group (highly decomposed + moderately decomposed) is confined to the tall-grass group of bog birch forests. The rhizomatous (roughly decomposed) litter is formed in the sedge-reed grass bog birch forests. The litter group (peaty + peatified + peat) is associated with the bog-herbaceous-moss group of forest types. The genetic associations of the litters (a) reliably characterize the edaphic conditions of bog birch forests and (b)correspond to formation of the peat of certain ecological groups. We found highly informative the acid-base parameters, the exchangeable cations (Ca2+ + Mg2+) and the total potential acidity, which differentiated the genetic associations of litter practically with 100% probability. The expediency of studying litters under groups of forest types rather than under separate types of bog birch forests was demonstrated.

  19. Soil mineral composition matters: response of microbial communities to phenanthrene and plant litter addition in long-term matured artificial soils.

    PubMed

    Babin, Doreen; Vogel, Cordula; Zühlke, Sebastian; Schloter, Michael; Pronk, Geertje Johanna; Heister, Katja; Spiteller, Michael; Kögel-Knabner, Ingrid; Smalla, Kornelia

    2014-01-01

    The fate of polycyclic aromatic hydrocarbons (PAHs) in soil is determined by a suite of biotic and abiotic factors, and disentangling their role in the complex soil interaction network remains challenging. Here, we investigate the influence of soil composition on the microbial community structure and its response to the spiked model PAH compound phenanthrene and plant litter. We used long-term matured artificial soils differing in type of clay mineral (illite, montmorillonite) and presence of charcoal or ferrihydrite. The soils received an identical soil microbial fraction and were incubated for more than two years with two sterile manure additions. The matured artificial soils and a natural soil were subjected to the following spiking treatments: (I) phenanthrene, (II) litter, (III) litter + phenanthrene, (IV) unspiked control. Total community DNA was extracted from soil sampled on the day of spiking, 7, 21, and 63 days after spiking. Bacterial 16S rRNA gene and fungal internal transcribed spacer amplicons were quantified by qPCR and subjected to denaturing gradient gel electrophoresis (DGGE). DGGE analysis revealed that the bacterial community composition, which was strongly shaped by clay minerals after more than two years of incubation, changed in response to spiked phenanthrene and added litter. DGGE and qPCR showed that soil composition significantly influenced the microbial response to spiking. While fungal communities responded only in presence of litter to phenanthrene spiking, the response of the bacterial communities to phenanthrene was less pronounced when litter was present. Interestingly, microbial communities in all artificial soils were more strongly affected by spiking than in the natural soil, which might indicate the importance of higher microbial diversity to compensate perturbations. This study showed the influence of soil composition on the microbiota and their response to phenanthrene and litter, which may increase our understanding of

  20. Soil Mineral Composition Matters: Response of Microbial Communities to Phenanthrene and Plant Litter Addition in Long-Term Matured Artificial Soils

    PubMed Central

    Babin, Doreen; Vogel, Cordula; Zühlke, Sebastian; Schloter, Michael; Pronk, Geertje Johanna; Heister, Katja; Spiteller, Michael; Kögel-Knabner, Ingrid; Smalla, Kornelia

    2014-01-01

    The fate of polycyclic aromatic hydrocarbons (PAHs) in soil is determined by a suite of biotic and abiotic factors, and disentangling their role in the complex soil interaction network remains challenging. Here, we investigate the influence of soil composition on the microbial community structure and its response to the spiked model PAH compound phenanthrene and plant litter. We used long-term matured artificial soils differing in type of clay mineral (illite, montmorillonite) and presence of charcoal or ferrihydrite. The soils received an identical soil microbial fraction and were incubated for more than two years with two sterile manure additions. The matured artificial soils and a natural soil were subjected to the following spiking treatments: (I) phenanthrene, (II) litter, (III) litter + phenanthrene, (IV) unspiked control. Total community DNA was extracted from soil sampled on the day of spiking, 7, 21, and 63 days after spiking. Bacterial 16S rRNA gene and fungal internal transcribed spacer amplicons were quantified by qPCR and subjected to denaturing gradient gel electrophoresis (DGGE). DGGE analysis revealed that the bacterial community composition, which was strongly shaped by clay minerals after more than two years of incubation, changed in response to spiked phenanthrene and added litter. DGGE and qPCR showed that soil composition significantly influenced the microbial response to spiking. While fungal communities responded only in presence of litter to phenanthrene spiking, the response of the bacterial communities to phenanthrene was less pronounced when litter was present. Interestingly, microbial communities in all artificial soils were more strongly affected by spiking than in the natural soil, which might indicate the importance of higher microbial diversity to compensate perturbations. This study showed the influence of soil composition on the microbiota and their response to phenanthrene and litter, which may increase our understanding of

  1. Fungal mycelium and decomposition of needle litter in three contrasting coniferous forests

    NASA Astrophysics Data System (ADS)

    Virzo De Santo, Amalia; Rutigliano, Flora Angela; Berg, Björn; Fioretto, Antonietta; Puppi, Gigliola; Alfani, Anna

    2002-08-01

    The fungal mycelium ingrowth and the rates of mass loss and respiration of needle litter of Pinus pinea, Pinus laricio, Pinus sylvestris, and Abies alba were investigated, in three coniferous forests, over a 3-year period by means of a composite set of incubations. In the early stages, the fungal flora of the decomposing needles was dominated by dematiaceous hyphomycetes and coelomycetes. Basidiomycetes reached a peak after 6 months on pine needles, but were absent from the N-rich needles of A. alba. Soil fungi ( Penicillium, Trichoderma, Absidia, Mucor sp. pl.) became most frequent in later stages. At the end of the study period, the total mycelium amount showed the lowest values in all pine needles incubated in the P. laricio forest and the highest ones in P. pinea needles incubated in the P. pinea forest. In all data sets, as in data for boreal forests examined for comparison, the concentration of litter fungal mycelium versus litter mass loss followed a common exponential model. However, in later stages, the amount of litter fungal mycelium was very close to that of the humus at the incubation site, thus supporting the hypothesis of a logistic growth pattern. Respiration rates of decomposing litters varied with season and decreased with litter age to values close to those of the humus at the incubation site. Respiration of water-saturated litter was negatively correlated with the total mycelium concentration, and this was consistent with the observation that in far-decomposed litter only a minor fraction of the total mycelium is alive.

  2. Comparison of four sampling methods for the detection of Salmonella in broiler litter.

    PubMed

    Buhr, R J; Richardson, L J; Cason, J A; Cox, N A; Fairchild, B D

    2007-01-01

    Experiments were conducted to compare litter sampling methods for the detection of Salmonella. In experiment 1, chicks were challenged orally with a suspension of naladixic acid-resistant Salmonella and wing banded, and additional nonchallenged chicks were placed into each of 2 challenge pens. Nonchallenged chicks were placed into each nonchallenge pen located adjacent to the challenge pens. At 7, 8, 10, and 11 wk of age the litter was sampled using 4 methods: fecal droppings, litter grab, drag swab, and sock. For the challenge pens, Salmonella-positive samples were detected in 3 of 16 fecal samples, 6 of 16 litter grab samples, 7 of 16 drag swabs samples, and 7 of 16 sock samples. Samples from the nonchallenge pens were Salmonella positive in 2 of 16 litter grab samples, 9 of 16 drag swab samples, and 9 of 16 sock samples. In experiment 2, chicks were challenged with Salmonella, and the litter in the challenge and adjacent nonchallenge pens were sampled at 4, 6, and 8 wk of age with broilers remaining in all pens. For the challenge pens, Salmonella was detected in 10 of 36 fecal samples, 20 of 36 litter grab samples, 14 of 36 drag swab samples, and 26 of 36 sock samples. Samples from the adjacent nonchallenge pens were positive for Salmonella in 6 of 36 fecal droppings samples, 4 of 36 litter grab samples, 7 of 36 drag swab samples, and 19 of 36 sock samples. Sock samples had the highest rates of Salmonella detection. In experiment 3, the litter from a Salmonella-challenged flock was sampled at 7, 8, and 9 wk by socks and drag swabs. In addition, comparisons with drag swabs that were stepped on during sampling were made. Both socks (24 of 36, 67%) and drag swabs that were stepped on (25 of 36, 69%) showed significantly more Salmonella-positive samples than the traditional drag swab method (16 of 36, 44%). Drag swabs that were stepped on had comparable Salmonella detection level to that for socks. Litter sampling methods that incorporate stepping on the sample

  3. Predicting climate change impacts on polar bear litter size

    PubMed Central

    Molnár, Péter K.; Derocher, Andrew E.; Klanjscek, Tin; Lewis, Mark A.

    2011-01-01

    Predicting the ecological impacts of climate warming is critical for species conservation. Incorporating future warming into population models, however, is challenging because reproduction and survival cannot be measured for yet unobserved environmental conditions. In this study, we use mechanistic energy budget models and data obtainable under current conditions to predict polar bear litter size under future conditions. In western Hudson Bay, we predict climate warming-induced litter size declines that jeopardize population viability: ∼28% of pregnant females failed to reproduce for energetic reasons during the early 1990s, but 40–73% could fail if spring sea ice break-up occurs 1 month earlier than during the 1990s, and 55–100% if break-up occurs 2 months earlier. Simultaneously, mean litter size would decrease by 22–67% and 44–100%, respectively. The expected timeline for these declines varies with climate-model-specific sea ice predictions. Similar litter size declines may occur in over one-third of the global polar bear population. PMID:21304515

  4. Effect of aluminum sulfate on litter composition and ammonia emission in a single flock of broilers up to 42 days of age.

    PubMed

    Madrid, J; López, M J; Orengo, J; Martínez, S; Valverde, M; Megías, M D; Hernández, F

    2012-08-01

    ammonia emissions from 37 to 42 days of age were significantly reduced by the alum treatment (P < 0.001), representing a reduction of 73.3%. The lower pH values might have reduced ammonia volatilization from the litter, with a corresponding positive effect on the building environment and poultry health. For these reasons, litter amendment with alum could be recommended as a way of reducing the pollution potential of European broiler facilities during a single flock cycle.

  5. Integrating plant litter quality, soil organic matter stabilization, and the carbon saturation concept

    USDA-ARS?s Scientific Manuscript database

    Recent research suggests labile plant litters promote the stabilization of soil organic matter (SOM) in physico-chemically protected fractions with relatively slow turnover. However, the effect of litter quality on SOM stabilization is inconsistent. Labile, ‘high quality’ litters characterized by hi...

  6. Reducing Weekend Litter (and Improving RA-Resident Interactions) in a College Residence Hall.

    ERIC Educational Resources Information Center

    Luyben, Paul D.; And Others

    1984-01-01

    Investigated the effectiveness of a litter reduction program, consisting of group assignment of responsibility and a token reward system, on weekend litter rates in college residence halls. Results indicated procedure was completely effective, with litter reduced to zero in all settings. (BL)

  7. Characterization of broiler cake and broiler litter, the by-products of two management practices.

    PubMed

    Sistani, K R; Brink, G E; McGowen, S L; Rowe, D E; Oldham, J L

    2003-10-01

    The application of broiler manure and bedding (litter) on land has been a long-used disposal method that benefits plant and soil. For proper manure management, factors such as nutrient content, house cleaning management, application methods, and many land, crop, and climatic factors must be considered. A study was undertaken to characterize broiler cake and broiler litter as the by-products of two management systems in Mississippi. Broiler cake and litter productions were quantified and analyzed for four flocks during 1999 and 2000. The overall means for broiler cake production were 12.50, 13.90, and 10.30 kg m(-2) for producers 1, 2, and 3, respectively. Significantly greater quantities of litter, 27.50, 29.0, and 28.30 kg m(-2) than cake were determined for the same producers. The cake and litter moisture averaged 455 and 277 g kg(-1), respectively. No significant differences were observed between cake and litter total N, NH4-N, total C, total P, and water-soluble P (WP). However, cake had significantly greater Ca, Mg, K, Cu, Fe, Mn, and Zn than litter. Approximately 16.8% of the broiler cake and 15.2% of the broiler litter total P were in the form of water-soluble P. The NH4-N content of the cake and the litter were 12.5% and 11.5% of the cake and litter total nitrogen, respectively. The results also showed the advantage of the decaking practice with respect to the quantity of the manure generated for land application. Approximately 57% of the litter remains in the poultry house with decaking practice after each growth cycle compared to the 0% for total cleanout practice.

  8. Country report: Broiler industry and broiler litter-related problems in the southeastern United States.

    PubMed

    Paudel, Krishna P; McIntosh, Christopher S

    2005-01-01

    This report describes the development of the broiler litter problem in the southeastern United States, including the economic opportunity and environmental challenges brought to the region by the industry. Through an analysis applied to the State of Georgia, land application of litter as a disposal alternative is examined along with its associated benefits. The analysis indicates that litter could be transported economically up to 256 km for cropland application. Excessive broiler litter production in a few concentrated regions is expected to stimulate the development of alternative approaches to broiler litter management, such as electricity generation.

  9. Factors affecting reproductive performance of white-tailed deer subjected to fixed-time artificial insemination or natural mating.

    PubMed

    Mellado, Miguel; Orta, Claudia G; Lozano, Eloy A; García, Jose E; Veliz, Francisco G; de Santiago, Angeles

    2013-01-01

    The objectives of this study were to examine the effects of several factors affecting fawning rate, litter size, litter weight and neonatal fawn mortality in white-tailed deer inseminated either transcervically or by means of laparoscopy. Oestrus synchronisation with a controlled internal drug release (CIDR)-based protocol and fixed-time artificial insemination (FTAI) was conducted in 130 white-tailed deer (Odocoileus virginianus texanus) during three reproductive seasons (2007-2009; 271 services) in a game-hunting ranch in a hot-arid environment (26°4' N, 101°25' W). Ninety additional non-treated does were exposed to bucks for natural mating. Fawning rate did not differ between AI methods (40.0 vs 45.0% for transcervical and laparoscopic AI, respectively). Overall fawning rate (proportion of all does fawning after FTAI and a subsequent period of buck exposure) did not differ between transcervical (89.5%), laparoscopic (80.3%) or natural (88.9%) insemination. Litter size per fawning doe was higher (P<0.05) in naturally-served does (1.65±0.48) than in transcervically-inseminated does (1.40±0.51) or in laparoscopically-inseminated does (1.48±0.50). The main conclusion was that no enhancement of fawning rate or litter size occurred as a result of intrauterine deposition of semen by laparoscopy compared with the transcervical insemination technique.

  10. Litter size at birth in purebred dogs--a retrospective study of 224 breeds.

    PubMed

    Borge, Kaja Sverdrup; Tønnessen, Ragnhild; Nødtvedt, Ane; Indrebø, Astrid

    2011-03-15

    Despite the long history of purebred dogs and the large number of existing breeds, few studies of canine litter size based upon a large number of breeds exist. Previous studies are either old or include only one or a few selected breeds. The aim of this large-scale retrospective study was to estimate the mean litter size in a large population of purebred dogs and to describe some factors that might influence the litter size. A total of 10,810 litters of 224 breeds registered in the Norwegian Kennel Club from 2006 to 2007 were included in the study. The overall mean litter size at birth was 5.4 (± 0.025). A generalized linear mixed model with a random intercept for breed revealed that the litter size was significantly influenced by the size of the breed, the method of mating and the age of the bitch. A significant interaction between breed size and age was detected, in that the expected number of puppies born decreased more for older bitches of large breeds. Mean litter size increased with breed size, from 3.5 (± 0.04) puppies in miniature breeds to 7.1 (± 0.13) puppies in giant breeds. No effect on litter size was found for the season of birth or the parity of the bitch. The large number of breeds and the detail of the registered information on the litters in this study are unique. In conclusion, the size of the breed, the age of the bitch and the method of mating were found to influence litter size in purebred dogs when controlling for breed, with the size of the breed as the strongest determinant. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Radiocesium migration in the litter layer of different forest types in Fukushima, Japan.

    PubMed

    Kurihara, Momo; Onda, Yuichi; Kato, Hiroaki; Loffredo, Nicolas; Yasutaka, Tetsuo; Coppin, Frederic

    2018-07-01

    Cesium-137 ( 137 Cs) migration in the litter layer consists of various processes, such as input via throughfall, output via litter decomposition, and input from deeper layers via soil organism activity. We conducted litter bag experiments over 2 years (December 2014-November 2016) to quantify the inputs and outputs of 137 Cs in the litter layer in a Japanese cedar plantation (Cryptomeria japonica) and a mixed broadleaf forest dominated by Quercus serrata located 40 km northwest of the Fukushima Dai-ichi Nuclear Power Plant. The experiments included four conditions, combining contaminated and non-contaminated litter and deeper layer material, and the inputs and outputs were estimated from the combination of 137 Cs increases and decreases in the litter layer under each condition. The 137 Cs dynamics differed between the two forests. In the C. japonica forest, some 137 Cs input via throughfall remained in the litter layer, and downward 137 Cs flux passed through the litter layer was 0.42 (/year).Upward flux of 137 Cs from the deeper layer was very restricted, < 0.017 (/year). In the broadleaf forest, migration of 137 Cs in throughfall into deeper layers was restricted, downward 137 Cs flux was less than 0.003 (/year).Upward input of 137 Cs from the deeper layer was prominent, 0.037 (/year). 137 Cs output via litter decomposition was observed in both forests. The flux in the C. japonica forest was slower than that in the broadleaf forest, 0.12 and 0.15 (/year), respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. The role of Juncus effusus litter quality and nutrient availability on organic matter decomposition in restored cutover bogs

    NASA Astrophysics Data System (ADS)

    Agethen, Svenja; Knorr, Klaus-Holger

    2017-04-01

    More than 90% of peatlands in Europe are degraded by drainage and subsequent land use. However, beneficial effects of functioning peatlands, most of all carbon storage, have long been recognized but remain difficult to recover. Fragmentation and a surrounding of intensively used agricultural catchments with excess nutrients in air and waters further affects the recovery of sites. Under such conditions, highly competitive species such as Juncus effusus colonize restored peatlands instead of peat forming Sphagnum. While the specific stoichiometry and chemical composition makes Sphagnum litter recalcitrant in decomposition and hence, effective in carbon sequestration, we know little about dynamics involving Juncus, although this species provides organic matter in high quantity and of rather labile quality. To better understand decomposition in context of litter quality and nutrient availability, we incubated different peat types for 70 days; I) recent, II) weakly degraded fossil, and III) earthyfied nutrient rich fossil peat, amended with two 13C pulse-labelled Juncus litter types (excessively fertilized "F", and nutrient poor "NF" plants grown for three years watered with MilliQ only), respectively. We determined anaerobic decomposition rates, compared potential rates extrapolated from pure materials with measured rates of the mixtures, and tracked the 13C in the solid, liquid, and gaseous phase. To characterize the biogeochemical conditions, inorganic and organic electron acceptors, hydrogen and organic acids, and total enzyme activity were monitored. For characterization of dissolved organic matter we used UV-Vis and fluorescence spectroscopy (parallel factor analysis), and for solid organic matter elemental analysis and FTIR spectroscopy. There were two main structural differences between litter types: "F" litter and its leachates contained more proteinaceous components, the C/N ratio was 20 in contrast to 60 of the "NF" litter. However, humic components and

  13. Impacts of elevated CO2 and O3 on aspen leaf litter chemistry and earthworm and springtail productivity

    Treesearch

    Timothy D. Meehan; Michael S. Crossley; Richard L. Lindroth

    2010-01-01

    Human alteration of atmospheric composition affects foliar chemistry and has possible implications for the structure and functioning of detrital communities. In this study, we explored the impacts of elevated carbon dioxide and ozone on aspen (Populus tremuloides) leaf litter chemistry, earthworm (Lumbricus terrestris) individual...

  14. Radiation effects on moisture variation in ponderosa pine litter

    Treesearch

    Clive M. Countryman

    1977-01-01

    This exploratory study indicated that considerable variation in the moisture content of litter can occur within short horizontal distances. The variations ere found to be caused primarily by differences in the amount of solar radiation received by the litter and in the degree of cooling by radiation at night. Because actual fuel moisture lags behind equilibrium...

  15. Water-soluble phosphorus in fresh broiler litter is dependent upon phosphorus concentration fed but not on fungal phytase supplementation.

    PubMed

    Applegate, T J; Joern, B C; Nussbaum-Wagler, D L; Angel, R

    2003-06-01

    This experiment determined the effects of different phosphorus (P) feeding programs on total and water-soluble P excretion by broilers. Ross 308, male broilers were fed an industry (IND) diet (0.48, 0.35, 0.31, and 0.30% nonphytate P; NPP), an industry diet with reduced NPP and supplemental phytase [IND + PT; 600 phytase units (FTU)/kg; 0.36, 0.26, 0.20, and 0.19% NPP], a diet to more closely meet the birds' NPP requirements in which NPP was reduced further with supplemental phytase (REQ + P; 600 FTU/kg; 0.36, 0.26, 0.19, and 0.09% NPP), or a diet with low-phytate(lpa 1-1) corn with supplemental phytase (LPA + P; 600 FTU/kg; 0.37, 0.29, 0.19, 0.19% NPP). These diets were fed from hatch to 17 d, 17 to 31 d, 31 to 42 d, and 42 to 49 d of age, respectively. Fungal phytase was analyzed prior to diet formulation. Diets were fed to six replicate pens of 39 birds per pen. Litter samples were collected at 49 d of age and frozen prior to analyses. Diet did not significantly affect broiler performance (average BW at 49 d = 3.03 kg), tibia, or toe ash throughout the study (P > 0.05). Litter from broilers fed the IND diet was significantly higher (P < or = 0.05) in total and water-soluble P (1.11 and 0.22% of DM, respectively) compared with litter from broilers fed IND + PT (0.84 and 0.14% of DM, respectively), REQ + P (0.78 and 0.11% of DM, respectively), or LPA + PT (0.64 and 0.12% of DM, respectively). Litter total and water-soluble P were not significantly different among broilers fed IND + PT, REQ + PT, or LPA + PT. In conclusion, phytase supplementation did not affect the solubility of P in the litter regardless of P feeding program.

  16. Broiler litter as a micronutrient source for cotton: concentrations in plant parts.

    PubMed

    Tewolde, H; Sistani, K R; Rowe, D E

    2005-01-01

    Analytically, poultry litter contains nearly all essential micronutrients but the extent of phytoavailability of these nutrients and whether cotton (Gossypium hirsutum L.) and other crop plants can receive adequate amounts of these nutrients from litter is not fully known. The objective of this research was to determine whether cotton receives sufficient amounts of Fe, Cu, Mn, and Zn from litter and estimate the efficiency of cotton in extracting these metal nutrients from litter in the absence of any other source of the micronutrients. The greenhouse research used plastic pots filled with approximately 11 kg of a 2:1 (v/v) sand to vermiculite growing mix. Cotton (cv. Stoneville 474) was grown in the pots fertilized with broiler litter at rates of 30, 60, 90, or 120 g pot(-1) in a factorial combination with four supplemental nutrient solution (NS) treatments. The nutrient solutions consisted of full Hoagland's nutrient solution (NS-full); a solution of the macronutrients N, P, K, Ca, and Mg (NS-macro); a solution of the micronutrients Fe, Zn, Mn, Cu, B, and Mo (NS-micro); and water (NS-none). Based on tissue nutrient analysis, a one-time broiler litter application supplied adequate amounts of Fe, Cu, and Mn to bring the concentration of these nutrients in upper leaves within published sufficiency ranges. Zinc, with <17 mg kg(-1) concentration in the upper leaves, was the only micronutrient below the established sufficiency range regardless of the rate of applied litter. Cotton extracted Fe and Mn more efficiently than Cu or Zn, removing as much as 8.8% of Fe and 7.2% of Mn supplied by 30 g litter pot(-1). In contrast, the extraction efficiency was 1.7% for Cu and 1.9% for Zn. Roots accumulated 58% of the total absorbed Fe and 64% of Cu, and leaves accumulated 32% of the Fe and only 13% of the Cu supplied by litter. In contrast, only 16% of the total absorbed Mn and 23% of Zn accumulated in roots while leaves accumulated 64% of the total Mn and 37% of Zn. These

  17. Investigation and comprehensive evaluation of the litter pollution on the Heishijiao beach in Dalian

    NASA Astrophysics Data System (ADS)

    Han, Mengdi; Zhao, Kaiyuan; Zhang, Yan; Sui, Chuanguo

    2018-02-01

    From November 2015 to August 2016, this paper conducted an investigation into the classification of the litter on the Heishijiao beach in Dalian, and made a comprehensive evaluation of the litter pollution on the beach in different seasons. According to the results, the litter on the Heishijiao beach in Dalian mainly come from human’s offshore activities and other wastes, and spring is the season which witnesses the largest quantity of litter resulting from the activities. Most of the fragmental wastes are glass, plastic and paper, while there is a little metal, rubber and wooden products. On the Heishijiao beach, most of the fragmental litter are small, followed by medium and large ones; outsized wastes are rare. The quantitative density of litter is highest in winter (9.0items/m2), with the average quantitative density of 4.6 items/m2; the qualitative density of litter is highest in spring (8 g/m2), with the average qualitative density of 6.0 g/m2. The results of the comprehensive evaluation show that the litter pollution on the Heishijiao beach stays between “Average” and “Unsatisfactory”.

  18. [Effects of Cunninghamia lanceolata-broadleaved tree species mixed leaf litters on active soil organic matter].

    PubMed

    Wang, Qing-kui; Wang, Si-long; Yu, Xiao-jun; Zhang, Jian; Liu, Yan-xin

    2007-06-01

    With incubation test, this paper studied the effects of Cunninghamia lanceolata leaf litter and its mixture with the litters of main broadleaved tree species in subtropical China, such as Alnus cremastogyne, Kalopanax septemlobus and Michelia macclurei on active soil organic matter. The results showed that adding leaf litters into soil could significantly increase soil microbial biomass C and N, respiration rate and dissolved organic C, and mixed leaf litters were more effective than C. lanceolata leaf litter in increasing soil dissolved organic C. By the end of the incubation, the increment of soil microbial biomass C and N, respiration rate, and dissolved organic C in treatments C. lanceolata leaf litter and C. lanceolata-broadleaved tree species mixed leaf litters was 49% and 63%, 35% and 75%, 65% and 100%, and 66% and 108%, respectively, compared with control. The addition of leaf litters had no significant effects on soil microbial quotient and microbial biomass C/N ratio.

  19. Pelage insulation, litter size, and ambient temperature impact maternal energy intake and offspring development during lactation

    PubMed Central

    Paul, Matthew J.; Tuthill, Christiana; Kauffman, Alexander S.; Zucker, Irving

    2010-01-01

    Energy balance during lactation critically influences survival and growth of a mother’s offspring, and hence, her reproductive success. Most experiments have investigated the influence of a single factor (e.g., ambient temperature [Ta] or litter size) on the energetics of lactation. Here, we determined the impact of multiple interventions, including increased conductive heat loss consequent to dorsal fur removal, cold exposure (Ta of 5°C versus 23°C), and differential lactational load from litters of different sizes (2 or 4 pups), on maternal energy balance and offspring development of Siberian hamsters (Phodopus sungorus). Lower Ta, fur removal, and larger litters were associated with increased maternal food consumption. Females exposed to multiple challenges (e.g., both fur loss and lower Ta) ate substantially more food than those exposed to a single challenge, with no apparent ceiling to elevated food intake (increases up to 538%). Thus, energy intake of dams under these conditions does not appear to be limited by feeding behavior or the size of the digestive tract. Housing at 5°C attenuated pup weight gain and increased pup mortality to more than 5 times that of litters housed at 23°C. Increases in the dam’s conductive heat loss induced by fur removal did not affect pup weight gain or survival, suggesting that effects of low Ta on pup weight gain and survival reflect limitations in the pups’ ability to ingest or incorporate energy. PMID:20184907

  20. Spatial patterns of plant litter in a tidal freshwater marsh and implications for marsh persistence.

    PubMed

    Elmore, Andrew J; Engelhardt, Katharina A M; Cadol, Daniel; Palinkas, Cindy M

    2016-04-01

    The maintenance of marsh platform elevation under conditions of sea level rise is dependent on mineral sediment supply to marsh surfaces and conversion of above- and belowground plant biomass to soil organic material. These physical and biological processes interact within the tidal zone, resulting in elevation-dependent processes contributing to marsh accretion. Here, we explore spatial pattern in a variable related to aboveground biomass, plant litter, to reveal its role in the maintenance of marsh surfaces. Plant litter persisting through the dormant season represents the more recalcitrant portion of plant biomass, and as such has an extended period of influence on ecosystem processes. We conducted a field and remote sensing analysis of plant litter height, aboveground biomass, vertical cover, and stem density (collectively termed plant litter structure) at a tidal freshwater marsh located within the Potomac River estuary, USA. LiDAR and field observations show that plant litter structure becomes more prominent with increasing elevation. Spatial patterns in litter structure exhibit stability from year to year and correlate with patterns in soil organic matter content, revealed by measuring the loss on ignition of surface sediments. The amount of mineral material embedded within plant litter decreases with increasing elevation, representing an important tradeoff with litter structure. Therefore, at low elevations where litter structure is short and sparse, the role of plant litter is to capture sediment; at high elevations where litter structure is tall and dense, aboveground litter contributes organic matter to soil development. This organic matter contribution has the potential to eclipse that of belowground biomass as the root:shoot ratio of dominant species at high elevations is low compared to that of dominant species at low elevations. Because of these tradeoffs in mineral and organic matter incorporation into soil across elevation gradients, the rate of

  1. Tracking senescence-induced patterns in leaf litter leachate using parallel factor analysis (PARAFAC) modeling and self-organizing maps

    NASA Astrophysics Data System (ADS)

    Wheeler, K. I.; Levia, D. F.; Hudson, J. E.

    2017-09-01

    In autumn, the dissolved organic matter (DOM) contribution of leaf litter leachate to streams in forested watersheds changes as trees undergo resorption, senescence, and leaf abscission. Despite its biogeochemical importance, little work has investigated how leaf litter leachate DOM changes throughout autumn and how any changes might differ interspecifically and intraspecifically. Since climate change is expected to cause vegetation migration, it is necessary to learn how changes in forest composition could affect DOM inputs via leaf litter leachate. We examined changes in leaf litter leachate fluorescent DOM (FDOM) from American beech (Fagus grandifolia Ehrh.) leaves in Maryland, Rhode Island, Vermont, and North Carolina and from yellow poplar (Liriodendron tulipifera L.) leaves from Maryland. FDOM in leachate samples was characterized by excitation-emission matrices (EEMs). A six-component parallel factor analysis (PARAFAC) model was created to identify components that accounted for the majority of the variation in the data set. Self-organizing maps (SOM) compared the PARAFAC component proportions of leachate samples. Phenophase and species exerted much stronger influence on the determination of a sample's SOM placement than geographic origin. As expected, FDOM from all trees transitioned from more protein-like components to more humic-like components with senescence. Percent greenness of sampled leaves and the proportion of tyrosine-like component 1 were found to be significantly different between the two genetic beech clusters, suggesting differences in photosynthesis and resorption. Our results highlight the need to account for interspecific and intraspecific variations in leaf litter leachate FDOM throughout autumn when examining the influence of allochthonous inputs to streams.

  2. Phosphorus runoff from waste water treatment biosolids and poultry litter applied to agricultural soils.

    PubMed

    White, John W; Coale, Frank J; Sims, J Thomas; Shober, Amy L

    2010-01-01

    Differences in the properties of organic phosphorus (P) sources, particularly those that undergo treatment to reduce soluble P, can affect soil P solubility and P transport in surface runoff. This 2-yr field study investigated soil P solubility and runoff P losses from two agricultural soils in the Mid-Atlantic region after land application of biosolids derived from different waste water treatment processes and poultry litter. Phosphorus speciation in the biosolids and poultry litter differed due to treatment processes and significantly altered soil P solubility and dissolved reactive P (DRP) and bioavailable P (FeO-P) concentrations in surface runoff. Runoff total P (TP) concentrations were closely related to sediment transport. Initial runoff DRP and FeO-P concentrations varied among the different biosolids and poultry litter applied. Over time, as sediment transport declined and DRP concentrations became an increasingly important component of runoff FeO-P and TP, total runoff P was more strongly influenced by the type of biosolids applied. Throughout the study, application of lime-stabilized biosolids and poultry litter increased concentrations of soil-soluble P, readily desorbable P, and soil P saturation, resulting in increased DRP and FeO-P concentrations in runoff. Land application of biosolids generated from waste water treatment processes that used amendments to reduce P solubility (e.g., FeCl(3)) did not increase soil P saturation and reduced the potential for DRP and FeO-P transport in surface runoff. These results illustrate the importance of waste water treatment plant process and determination of specific P source coefficients to account for differential P availability among organic P sources.

  3. Using a Feedback Environment to Improve Creative Performance: A Dynamic Affect Perspective.

    PubMed

    Gong, Zhenxing; Zhang, Na

    2017-01-01

    Prior research on feedback and creative performance has neglected the dynamic nature of affect and has focused only on the influence of positive affect. We argue that creative performance is the result of a dynamic process in which a person experiences a phase of negative affect and subsequently enters a state of high positive affect that is influenced by the feedback environment. Hierarchical regression was used to analyze a sample of 264 employees from seven industry firms. The results indicate that employees' perceptions of a supportive supervisor feedback environment indirectly influence their level of creative performance through positive affect (t2); the negative affect (t1) moderates the relationship between positive affect (t2) and creative performance (t2), rendering the relationship more positive if negative affect (t1) is high. The change in positive affect mediates the relationship between the supervisor feedback environment and creative performance; a decrease in negative affect moderates the relationship between increased positive affect and creative performance, rendering the relationship more positive if the decrease in negative affect is large. The implications for improving the creative performances of employees are further discussed.

  4. Using a Feedback Environment to Improve Creative Performance: A Dynamic Affect Perspective

    PubMed Central

    Gong, Zhenxing; Zhang, Na

    2017-01-01

    Prior research on feedback and creative performance has neglected the dynamic nature of affect and has focused only on the influence of positive affect. We argue that creative performance is the result of a dynamic process in which a person experiences a phase of negative affect and subsequently enters a state of high positive affect that is influenced by the feedback environment. Hierarchical regression was used to analyze a sample of 264 employees from seven industry firms. The results indicate that employees’ perceptions of a supportive supervisor feedback environment indirectly influence their level of creative performance through positive affect (t2); the negative affect (t1) moderates the relationship between positive affect (t2) and creative performance (t2), rendering the relationship more positive if negative affect (t1) is high. The change in positive affect mediates the relationship between the supervisor feedback environment and creative performance; a decrease in negative affect moderates the relationship between increased positive affect and creative performance, rendering the relationship more positive if the decrease in negative affect is large. The implications for improving the creative performances of employees are further discussed. PMID:28861025

  5. Highly Active Ice Nuclei from Tree Leaf Litters Retain Activity for Decades

    NASA Astrophysics Data System (ADS)

    Schnell, R. C.; Hill, T. C. J.

    2015-12-01

    Biogenic ice nuclei (IN) studied since the 1960s were first observed in tree leaf litters, in a few bacteria species and later in fungi and lichens. Recently, viable IN bacteria in precipitation have been used as a metric of their possible role in precipitation formation. Although bacterial IN activity is deactivated by a variety of common environmental stresses, we present data showing that IN found in a potpourri of decayed plant leaves, bacteria, molds and fungi etc. in plant litters are exceptionally stable and active over decades while in storage. As such, their atmospheric IN potential is worthy of further study due to their environmental persistence. In August 1970 litter collected in a grove of deciduous trees near Red Deer, AB, Canada was tested for IN (drop freezing technique). The sample initiated ice at -4C with 109 IN per gram of litter active at -10C. A few kilograms were stored in a plastic bag and tested every few years for IN content; the IN activity remained essentially unchanged over 40 years. In 2011, litter collected in the same grove had the same IN activity as the sample tested over the intervening 40 years. Boiling a gram sample of this litter in 100 grams of water deactivated 99 % of the IN activity down to -13C. None of 88 different bacteria cultures several of which appeared to Pseudomonads (common IN producing bacteria) from the fresh litter produced any active IN. A sample of the litter was placed on the top of a 15 cm column of laboratory grade kaolin and water dripped onto the litter. Ten days later the water reached the bottom of the column. The kaolin was dried and tested for IN. The prior essentially IN free kaolin now exhibited IN activity at -4C with 105 IN active at -10C. The litter exposed kaolin retained the IN activity for 25 years. Baking the kaolin removed the active IN. This suggests that IN activity attributed to kaolin particles sometimes seen at the nucleus of snow crystals could be of biological origin.

  6. Patient Litter System Response in a Full-Scale CH-46 Crash Test.

    PubMed

    Weisenbach, Charles A; Rooks, Tyler; Bowman, Troy; Fralish, Vince; McEntire, B Joseph

    2017-03-01

    U.S. Military aeromedical patient litter systems are currently required to meet minimal static strength performance requirements at the component level. Operationally, these components must function as a system and are subjected to the dynamics of turbulent flight and potentially crash events. The first of two full-scale CH-46 crash tests was conducted at NASA's Langley Research Center and included an experiment to assess patient and litter system response during a severe but survivable crash event. A three-tiered strap and pole litter system was mounted into the airframe and occupied by three anthropomorphic test devices (ATDs). During the crash event, the litter system failed to maintain structural integrity and collapsed. Component structural failures were recorded from the litter support system and the litters. The upper ATD was displaced laterally into the cabin, while the middle ATD was displaced longitudinally into the cabin. Acceleration, force, and bending moment data from the instrumented middle ATD were analyzed using available injury criteria. Results indicated that a patient might sustain a neck injury. The current test illustrates that a litter system, with components designed and tested to static requirements only, experiences multiple component structural failures during a dynamic crash event and does not maintain restraint control of its patients. It is unknown if a modern litter system, with components tested to the same static criteria, would perform differently. A systems level dynamic performance requirement needs to be developed so that patients can be provided with protection levels equivalent to that provided to seated aircraft occupants. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  7. 17beta-Estradiol and testosterone in drainage and runoff from poultry litter applications to tilled and no-till crop land under irrigation.

    PubMed

    Jenkins, Michael B; Endale, Dinku M; Schomberg, Harry H; Hartel, Peter G; Cabrera, Miguel L

    2009-06-01

    Thirteen million [corrected] metric tons of poultry litter are produced annually by poultry producers in the U.S. Poultry litter contains the sex hormones estradiol and testosterone, endocrine disruptors that have been detected in surface waters. The objective of this study was to evaluate the potential impact of poultry litter applications on estradiol and testosterone concentrations in subsurface drainage and surface runoff in irrigated crop land under no-till and conventional-till management. We conducted an irrigation study in fall of 2001 and spring of 2002. Four treatments, no-till plus poultry litter, conventional-till plus poultry litter, no-till plus conventional fertilizer, and conventional-till plus conventional fertilizer, were evaluated. Flow-weighted concentration and load ha(-1) of the two hormones were measured in drainage and runoff. Soil concentrations of estradiol and testosterone were measured. Based on comparisons to the conventional fertilizer (and control) treatments, poultry litter did not add to the flow-weighted concentration or load ha(-1) of either estradiol or testosterone in subsurface drainage or surface runoff. Significant differences were, however, observed between tillage treatments: flow-weighted concentrations of estradiol were greater for no-till than conventional-till plots of the June irrigation; and runoff loads of both estradiol and testosterone were less from no-till than conventional-till plots for the November irrigation. Although the differences between no-till and conventional-tillage appeared to affect the hydrologic transport of both hormones, the differences appeared to have inconsequential environmental impact.

  8. The multidimensional causal factors of 'wet litter' in chicken-meat production.

    PubMed

    Dunlop, Mark W; Moss, Amy F; Groves, Peter J; Wilkinson, Stuart J; Stuetz, Richard M; Selle, Peter H

    2016-08-15

    The problem of 'wet litter', which occurs primarily in grow-out sheds for meat chickens (broilers), has been recognised for nearly a century. Nevertheless, it is an increasingly important problem in contemporary chicken-meat production as wet litter and associated conditions, especially footpad dermatitis, have developed into tangible welfare issues. This is only compounded by the market demand for chicken paws and compromised bird performance. This review considers the multidimensional causal factors of wet litter. While many causal factors can be listed it is evident that the critical ones could be described as micro-environmental factors and chief amongst them is proper management of drinking systems and adequate shed ventilation. Thus, this review focuses on these environmental factors and pays less attention to issues stemming from health and nutrition. Clearly, there are times when related avian health issues of coccidiosis and necrotic enteritis cannot be overlooked and the development of efficacious vaccines for the latter disease would be advantageous. Presently, the inclusion of phytate-degrading enzymes in meat chicken diets is routine and, therefore, the implication that exogenous phytases may contribute to wet litter is given consideration. Opinion is somewhat divided as how best to counter the problem of wet litter as some see education and extension as being more beneficial than furthering research efforts. However, it may prove instructive to assess the practice of whole grain feeding in relation to litter quality and the incidence of footpad dermatitis. Additional research could investigate the relationships between dietary concentrations of key minerals and the application of exogenous enzymes with litter quality. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  9. Climate change triggers effects of fungal pathogens and insect herbivores on litter decomposition

    NASA Astrophysics Data System (ADS)

    Butenschoen, Olaf; Scheu, Stefan

    2014-10-01

    Increasing infestation by insect herbivores and pathogenic fungi in response to climate change will inevitably impact the amount and quality of leaf litter inputs into the soil. However, little is known on the interactive effect of infestation severity and climate change on litter decomposition, and no such study has been published for deciduous forests in Central Europe. We assessed changes in initial chemical quality of beech (Fagus sylvatica L.) and maple litter (Acer platanoides L.) in response to infestation by the gall midge Mikiola fagi Hart. and the pathogenic fungus Sawadaea tulasnei Fuckel, respectively, and investigated interactive effects of infestation severity, changes in temperature and soil moisture on carbon mineralization in a short-term laboratory study. We found that infestation by the gall midge M. fagi and the pathogenic fungus S. tulasnei significantly changed the chemical quality of beech and maple litter. Changes in element concentrations were generally positive and more pronounced, and if negative less pronounced for maple than beech litter most likely due to high quality fungal tissue remaining on litter after abscission. More importantly, alterations in litter chemical quality did not translate to distinct patterns of carbon mineralization at ambient conditions, but even low amounts of infested litter accelerated carbon mineralization at moderately increased soil moisture and in particular at higher temperature. Our results indicate that insect herbivores and fungal pathogens can markedly alter initial litter chemical quality, but that afterlife effects on carbon mineralization depend on soil moisture and temperature, suggesting that increased infestation severity under projected climate change potentially increases soil carbon release in deciduous forests in Central Europe.

  10. Paleobotanical implications of drifted seeds and fruits from modern mangrove litter, Twin Cays, Belize

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burnham, R.J.

    1990-08-01

    Fruits and seeds were quantitatively sampled from litter at two sites on a mangrove island off the coast of Belize. The collections indicate that a significant number of species are drifted to the island by the prevailing currents and have the potential to record the major elements of the nearby mainland coastal and streamside flora. There is almost no overlap between the drifted fruit and seed flora and the flora growing on the island, whereas the leaf litter reflects the island flora both qualitatively and quantitatively with a reasonable degree of accuracy. These observations indicate that approaches to paleoecological andmore » paleofloristic reconstructions of ancient floras based on accumulation of organic remains can differ substantially depending on the organ type studied. Studies which can take advantage of both vegetative and reproductive fossil remains with an appropriate methodology for sampling and analyzing the data can provide information on ancient environments at more than one spatial scale.« less

  11. Dynamics of microbial communities during decomposition of litter from pioneering plants in initial soil ecosystems

    NASA Astrophysics Data System (ADS)

    Esperschütz, J.; Zimmermann, C.; Dümig, A.; Welzl, G.; Buegger, F.; Elmer, M.; Munch, J. C.; Schloter, M.

    2013-07-01

    In initial ecosystems, concentrations of all macro- and micronutrients can be considered as extremely low. Plant litter therefore strongly influences the development of a degrader's food web and is an important source for C and N input into soil in such ecosystems. In the present study, a 13C litter decomposition field experiment was performed for 30 weeks in initial soils from a post-mining area near the city of Cottbus (Germany). Two of this region's dominant but contrasting pioneering plant species (Lotus corniculatus L. and Calamagrostis epigejos L.) were chosen to investigate the effects of litter quality on the litter decomposing microbial food web in initially nutrient-poor substrates. The results clearly indicate the importance of litter quality, as indicated by its N content, its bioavailability for the degradation process and the development of microbial communities in the detritusphere and soil. The degradation of the L. corniculatus litter, which had a low C / N ratio, was fast and showed pronounced changes in the microbial community structure 1-4 weeks after litter addition. The degradation of the C. epigejos litter material was slow and microbial community changes mainly occurred between 4 and 30 weeks after litter addition to the soil. However, for both litter materials a clear indication of the importance of fungi for the degradation process was observed both in terms of fungal abundance and activity (13C incorporation activity)

  12. Beach litter sourcing: A trawl along the Northern Ireland coastline.

    PubMed

    Williams, A T; Randerson, P; Allen, C; Cooper, J A G

    2017-09-15

    Fourteen non-recreational coastal locations in Northern Ireland were investigated as to whether beach litter deposition was related to seasonal or site specific factors. Litter items were counted in 100m width transects and 1km strand-line surveys over a five-season period (autumn to autumn). Survey sites comprised fishing ports; estuarine areas, north (high energy) and east coast (low energy) beaches. Fishing ports accumulated the most litter. In the 100m beach surveys, plastics, string and cord, bottle caps, food items, rope, and drink containers dominated. In strand-line surveys, large plastic pieces were dominant, followed by rope, string and cord, strapping bands (absent on beach surveys), cloth, wood (mainly pallets, fish boxes) and metal items. Multivariate analyses revealed major litter category differences between the ports and all other sites, with a lesser distinction between exposed and estuarine sites. There was no simple coastline trend and no apparent effect of seasonality between samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Litter aeration and spread of Salmonella in broilers.

    PubMed

    Bodí, Sara González; Garcia, Arantxa Villagra; García, Santiago Vega; Orenga, Clara Marín

    2013-08-01

    Litter quality in the poultry sector is one of the main parameters of health, productivity, and animal welfare. Therefore, innovative management methods have been developed to improve the quality of litter. One of them is litter aeration (LA) by tumbling. However, there is little information related to the effect of this technique on the spreading of pathogens of public health importance such as Salmonella. In this context, the objective of this study was to determine the epidemiology of Salmonella in poultry farms, when serial LA were implemented during the rearing cycle of broilers. For this purpose, an experimental broiler farm with 3 identical rooms was used in the study. Two rooms were assigned to the LA treatment, and the other one served as the control room. Environmental samples were taken in poultry houses after LA in 4 consecutive weeks at the end of the cycle. All samples collected were analyzed according to the standards of the International Organization for Standardization (ISO 6579:2002, Annex D). The results of this study showed that in the control and treated rooms, the percentage of positive samples for Salmonella decreased in the first 3 LA sessions (LA 1, LA 2, and LA 3). However, in the last LA session of rearing (LA 4), the percentage of positive samples increased from 8.2 to 33.2% in the control room instead the treated rooms where the positive samples decreased (P = 0.017). Thus, the aeration of the litter as litter management technique in poultry broiler production does not increase the shedding or the spread of Salmonella throughout broiler houses. In addition, it could be an effective technique to reduce the infective pressure of this bacterium in several areas of the farm or in certain moments of the rearing period with more risk of multiplication and spreading of Salmonella.

  14. Birth order, family environments, academic and affective outcomes.

    PubMed

    Marjoribanks, Kevin

    2003-06-01

    Relations were examined among birth order, family social status, family learning environments, and a set of affective and academic outcomes. Data were collected as part of an Australian longitudinal study (4,171 females and 3,718 males). Analysis suggested that birth order continued to have small but significant associations with adolescents' self-concept and educational aspirations and with young adults' educational attainment, after taking into account differences in family social status and family learning environments.

  15. Distribution of plant nutrient elements and carbon in particle size fractions of broiler litter ash

    USDA-ARS?s Scientific Manuscript database

    An estimated 10.8 million tons of broiler litter and 3.0 million tons of turkey litter were produced in the United States in 2009. Poultry litter is a mixture of manure, bedding material (e.g., wood chips, sawdust, or straw), feathers, and spilled feed. Poultry litter contains high levels of Ca, N...

  16. Plumage condition, body weight, mortality, and zootechnical performances: the effects of linings and litter provision in furnished cages for laying hens.

    PubMed

    Guinebretière, M; Huneau-Salaün, A; Huonnic, D; Michel, V

    2013-01-01

    This experiment was designed to determine the effect of litter provision and lining in nests and pecking and scratching areas on health and zootechnical performances. Research was carried out in furnished cages, each housing 60 beak-trimmed ISA Brown hens. Four different treatments were compared in a factorial arrangement, including 2 different nest linings (artificial turf versus plastic mesh), either used alone or combined with the use of litter (wheat bran) spread over the rubber mat in the pecking and scratching area (PSA). An additional treatment using artificial turf mat in the PSA and nests (as commonly used in commercial flocks) was used to compare the effect of PSA lining in the other treatments. Zootechnical performances (laying rate, egg weight, and feed intake) were unaffected by PSA lining or by nest lining. The use of artificial turf mats in the PSA resulted in less feather loss than rubber mats, especially on breast and cloaca/vent areas. No consequences were observed on BW or mortality. However, the use of plastic mesh in nests was seen to increase mortality in comparison with artificial turf mats, without affecting plumage condition and BW. Although wheat bran provision did not influence feed intake and laying rate, litter provision did result in slightly higher mean egg weight. Moreover, BW tended to be lower when litter was distributed in cages, and neck and breast plumage condition improved. The distribution of litter was not seen to have any effect on mortality. The provision of litter and the lining of the PSA and nests to improve the welfare of caged laying hens have an effect on mortality, plumage quality, and some zootechnical performances. These results show the importance of choosing the most suitable linings and litter to obtain the best possible compromise between the ethological needs of laying hens, zootechnical performance, and animal health.

  17. Effect of intravenous endotoxin on blood cell profiles of broilers housed in cages and floor litter environments.

    PubMed

    Wang, W; Wideman, R F; Chapman, M E; Bersi, T K; Erf, G F

    2003-12-01

    Commercial broilers are constantly exposed to airborne microorganisms and endotoxin (lipopolysaccharide, LPS). It has been shown that microbial contamination of the air was higher in broiler houses using floor litter than in broiler houses using netting-type floors. The current study evaluated the effect of housing conditions on blood leukocyte profiles and tested the hypothesis that, when compared to broilers reared in clean stainless steel cages (Cage group), broilers raised on floor litter (Floor group) should experience a higher environmental challenge and have a desensitized immune system that may exhibit better tolerance/resistance to subsequent intravenous LPS challenge. Hematological parameters were evaluated prior to and following i.v. administration of 1 mg/kg BW Salmonella typhimurium LPS (dissolved at 1 mg/0.25 mL in PBS) or i.v. injection of 0.25 mL/kg BW PBS alone. The results showed that prior to LPS/PBS injection, broilers in the cage group had higher heterophil and monocyte concentrations, a higher B cell percentage within the lymphocyte population, and a higher heterophil to lymphocyte (H:L) ratio in the blood. The i.v. LPS injection resulted in 25% mortality in the cage group and 42% mortality in the floor group within 8 h post-injection. LPS reduced the concentrations of total white blood cells (WBC) and all differential WBC except eosinophils and increased thrombocyte concentrations within 1 h post-injection in both groups. All of these values returned to their respective pre-injection levels within 48 h post-injection in the surviving birds. The two groups exhibited similar overall hematological changes after LPS injection except that the cage group showed a higher H:L ratio at 8 h post-injection and a lower B-cell percentage within the lymphocyte population at 48 h post-injection when compared with the floor group. We concluded that the immune systems of broilers reared on floor litter were desensitized and exhibited less pronounced leukocyte

  18. Influence of Different Forest System Management Practices on Leaf Litter Decomposition Rates, Nutrient Dynamics and the Activity of Ligninolytic Enzymes: A Case Study from Central European Forests

    PubMed Central

    Schulz, Elke; Schloter, Michael; Buscot, François; Hofrichter, Martin; Krüger, Dirk

    2014-01-01

    Leaf litter decomposition is the key ecological process that determines the sustainability of managed forest ecosystems, however very few studies hitherto have investigated this process with respect to silvicultural management practices. The aims of the present study were to investigate the effects of forest management practices on leaf litter decomposition rates, nutrient dynamics (C, N, Mg, K, Ca, P) and the activity of ligninolytic enzymes. We approached these questions using a 473 day long litterbag experiment. We found that age-class beech and spruce forests (high forest management intensity) had significantly higher decomposition rates and nutrient release (most nutrients) than unmanaged deciduous forest reserves (P<0.05). The site with near-to-nature forest management (low forest management intensity) exhibited no significant differences in litter decomposition rate, C release, lignin decomposition, and C/N, lignin/N and ligninolytic enzyme patterns compared to the unmanaged deciduous forest reserves, but most nutrient dynamics examined in this study were significantly faster under such near-to-nature forest management practices. Analyzing the activities of ligninolytic enzymes provided evidence that different forest system management practices affect litter decomposition by changing microbial enzyme activities, at least over the investigated time frame of 473 days (laccase, P<0.0001; manganese peroxidase (MnP), P = 0.0260). Our results also indicate that lignin decomposition is the rate limiting step in leaf litter decomposition and that MnP is one of the key oxidative enzymes of litter degradation. We demonstrate here that forest system management practices can significantly affect important ecological processes and services such as decomposition and nutrient cycling. PMID:24699676

  19. Severe zinc responsive dermatosis in a litter of Pharaoh Hounds.

    PubMed

    Campbell, Gregory A; Crow, Dennis

    2010-07-01

    A litter of 3-month-old Pharaoh Hound puppies presented to the referring veterinarian with severe generalized erythematous-crusted papules with pruritus, accompanied by exfoliation and erythema of footpads, inappetence, lethargy, and retarded growth. Three of 5 puppies (2 male and 1 female) were affected. Representative areas were biopsied from 1 affected male puppy and were routinely processed. Histologically, there was marked epidermal hyperplasia with a disorganized appearance of the epidermis and massive parakeratotic hyperkeratosis, compatible with zinc-responsive dermatosis. Low serum zinc concentrations were documented, and the affected animals partially responded to intravenous zinc supplementation but did not respond to oral supplementation. One male puppy died as a result of unrelated causes and was necropsied. The remaining 4 puppies were followed over 2 years. Growth was stunted, and enamel hypoplasia of permanent dentition developed compared with unaffected littermates. Intravenous zinc supplementation at 3-4 week intervals was required to prevent further skin lesion development. One dog died at 3 years of age of renal failure.

  20. A test of the hierarchical model of litter decomposition.

    PubMed

    Bradford, Mark A; Veen, G F Ciska; Bonis, Anne; Bradford, Ella M; Classen, Aimee T; Cornelissen, J Hans C; Crowther, Thomas W; De Long, Jonathan R; Freschet, Gregoire T; Kardol, Paul; Manrubia-Freixa, Marta; Maynard, Daniel S; Newman, Gregory S; Logtestijn, Richard S P; Viketoft, Maria; Wardle, David A; Wieder, William R; Wood, Stephen A; van der Putten, Wim H

    2017-12-01

    Our basic understanding of plant litter decomposition informs the assumptions underlying widely applied soil biogeochemical models, including those embedded in Earth system models. Confidence in projected carbon cycle-climate feedbacks therefore depends on accurate knowledge about the controls regulating the rate at which plant biomass is decomposed into products such as CO 2 . Here we test underlying assumptions of the dominant conceptual model of litter decomposition. The model posits that a primary control on the rate of decomposition at regional to global scales is climate (temperature and moisture), with the controlling effects of decomposers negligible at such broad spatial scales. Using a regional-scale litter decomposition experiment at six sites spanning from northern Sweden to southern France-and capturing both within and among site variation in putative controls-we find that contrary to predictions from the hierarchical model, decomposer (microbial) biomass strongly regulates decomposition at regional scales. Furthermore, the size of the microbial biomass dictates the absolute change in decomposition rates with changing climate variables. Our findings suggest the need for revision of the hierarchical model, with decomposers acting as both local- and broad-scale controls on litter decomposition rates, necessitating their explicit consideration in global biogeochemical models.

  1. Toxicity of iron oxide nanoparticles to grass litter decomposition in a sandy soil

    NASA Astrophysics Data System (ADS)

    Rashid, Muhammad Imtiaz; Shahzad, Tanvir; Shahid, Muhammad; Imran, Muhammad; Dhavamani, Jeyakumar; Ismail, Iqbal M. I.; Basahi, Jalal M.; Almeelbi, Talal

    2017-02-01

    We examined time-dependent effect of iron oxide nanoparticles (IONPs) at a rate of 2000 mg kg-1 soil on Cynodon dactylon litter (3 g kg-1) decomposition in an arid sandy soil. Overall, heterotrophic cultivable bacterial and fungal colonies, and microbial biomass carbon were significantly decreased in litter-amended soil by the application of nanoparticles after 90 and 180 days of incubation. Time dependent effect of nanoparticles was significant for microbial biomass in litter-amended soil where nanoparticles decreased this variable from 27% after 90 days to 49% after 180 days. IONPs decreased CO2 emission by 28 and 30% from litter-amended soil after 90 and 180 days, respectively. These observations indicated that time-dependent effect was not significant on grass-litter carbon mineralization efficiency. Alternatively, nanoparticles application significantly reduced mineral nitrogen content in litter-amended soil in both time intervals. Therefore, nitrogen mineralization efficiency was decreased to 60% after 180 days compared to that after 90 days in nanoparticles grass-litter amended soil. These effects can be explained by the presence of labile Fe in microbial biomass after 180 days in nanoparticles amendment. Hence, our results suggest that toxicity of IONPs to soil functioning should consider before recommending their use in agro-ecosystems.

  2. Benthic marine litter in four Gulfs in Greece, Eastern Mediterranean; abundance, composition and source identification

    NASA Astrophysics Data System (ADS)

    Koutsodendris, Andreas; Papatheodorou, George; Kougiourouki, Ourania; Georgiadis, Michalis

    2008-04-01

    The types, abundance, distribution and sources of benthic marine litter found in four Greek Gulfs (Patras, Corinth, Echinades and Lakonikos) were studied using bottom trawl nets. Mean distribution and weight densities range between 72-437 Item/km 2 and 6.7-47.4 kg/km 2. Litter items were sorted into material and usage categories. Plastic litter (56%) is the most dominant material category followed by metal (17%) and glass (11%). Beverage packaging (32%) is the dominant usage category followed by general packaging (28%) and food packaging (21%). Based on the typological results three dominant litter sources were identified; land-based, vessel-based and fishery-based. Application of factor analysis (R- and Q-mode) conducted on both material and usage litter datasets confirmed the existence of the three dominant litter sources. Q-mode analysis further resulted in the quantification of the litter sources; land-based ones provided the majority (69%) of the total litter items followed by vessel-based (26%) and fishery-based (5%) sources. Diverse environmental parameters influence significantly these amounts among the four Gulfs.

  3. Application of gypsum to control P runoff from poultry litter fertilization of pasture

    USDA-ARS?s Scientific Manuscript database

    This paper will discuss the utilization of gypsum (CaSO4 .2H2O) to reduce P losses from surface runoff when poultry litter is used as a fertilizer source in agriculture. Utilization of poultry litter as a fertilizer source is common in regions with intense poultry production. While poultry litter ...

  4. Comparative effects of sulfuric and nitric acid rain on litter decomposition and soil microbial community in subtropical plantation of Yangtze River Delta region.

    PubMed

    Liu, Xin; Zhang, Bo; Zhao, Wenrui; Wang, Ling; Xie, Dejin; Huo, Wentong; Wu, Yanwen; Zhang, Jinchi

    2017-12-01

    Acid rain is mainly caused by dissolution of sulfur dioxide and nitrogen oxides in the atmosphere, and has a significant negative effect on ecosystems. The relative composition of acid rain is changing gradually from sulfuric acid rain (SAR) to nitric acid rain (NAR) with the rapidly growing amount of nitrogen deposition. In this study, we investigated the impact of simulated SAR and NAR on litter decomposition and the soil microbial community over four seasons since March 2015. Results first showed that the effects of acid rain on litter decomposition and soil microbial were positive in the early period of the experiment, except for SAR on soil microbes. Second, soil pH with NAR decreased more rapidly with the amount of acid rain increased in summer than with SAR treatments. Only strongly acid rain (both SAR and NAR) was capable of depressing litter decomposition and its inhibitory effect was stronger on leaf than on fine root litter. Meanwhile, NAR had a higher inhibitory effect on litter decomposition than SAR. Third, in summer, autumn and winter, PLFAs were negatively impacted by the increased acidity level resulting from both SAR and NAR. However, higher acidity level of NAR (pH=2.5) had the strongest inhibitory impact on soil microbial activity, especially in summer. In addition, Gram-negative bacteria (cy19:0) and fungi (18:1ω9) were more sensitive to both SAR and NAR, and actinomycetes was more sensitive to SAR intensity. Finally, soil total carbon, total nitrogen and pH were the most important soil property factors affecting soil microbial activity, and high microbial indices (fungi/bacteria) with high soil pH. Our results suggest that the ratio of SO 4 2- to NO 3 - in acid rain is an important factor which could affect litter decomposition and soil microbial in subtropical forest of China. Copyright © 2017. Published by Elsevier B.V.

  5. Comparison of placental traits and their relation to litter size and parity weight in sheep.

    PubMed

    Ocak, S; Emsen, E; Köycegiz, F; Kutluca, M; Onder, H

    2009-10-01

    The relationships between genotype and placental traits, parity and litter weight (LW), and factors affecting these characteristics were investigated in this study. In total, 112 ewes (Romanov crossbred and local breeds) were utilized. One-way ANOVA was used for statistical comparison, and a Pearson correlation was used to determine the relationships between the variables. Significant differences in parity weight within genotype and breed have been determined. A negative correlation was revealed between placental weight (PW) and placental efficiency (r = -0.743, P < 0.01; and r = -0.732, P < 0.01). There was no relationship between litter sex and placental traits. Birth type had a significant effect on PW (P < 0.05), and significant differences within sex-birth type interactions occurred (P < 0.05). The results of the present study have shown a positive correlation between cotyledon density and placental efficiency among all genotypes and breeds that were used in the study. In conclusion, it has been determined that placental traits were affected by LW and Romanov crossbreed ewes had greater PW than local breeds. Further studies are required to investigate the relationship between parity and placental traits in sheep.

  6. Do Laboratory Mouse Females that Lose Their Litters Behave Differently around Parturition?

    PubMed Central

    Weber, Elin M.; Hultgren, Jan

    2016-01-01

    Efficiency in laboratory mouse breeding is hampered by poor reproductive performance, including the loss of entire litters shortly after birth. However, the underlying mechanisms are not yet fully understood and establishing the cause of death in laboratory mouse pups can be complicated. Newborn mouse pups are generally hidden in nests, dead pups are often eaten by the female, and the widespread practice of leaving periparturient females undisturbed complicates inspection, which may delay the discovery of pup loss. In order to efficiently prevent problems with litter loss, it is important to find key factors for survival. We investigated differences in periparturient behavior between female laboratory mice whose pups survived until weaning and females whose entire litters were lost. Video recordings of 82 primiparous females of the C57BL/6 strain or knockouts with C57BL/6 background were used. The mice were observed from 24 h before until 24 h after parturition and female behaviors coded using a pre-established ethogram. The relationship between behavior and survival was analyzed using logistic models, where litter survival was regressed on the proportion of 30-s observations with at least one occurrence of the behavior. We found that females with surviving litters performed more nest building behavior during the last 24 h before parturition (p = 0.004) and spent less time outside the nest during the entire observation period (p = 0.001). Increased litter survival was also associated with more passive maternal behaviors and the female ignoring still pups less. Females that lost their litters performed more parturition-related behaviors, suggesting prolonged labor. The results indicate that maternal behavior plays a significant role in laboratory mouse pup survival. Complications at parturition also contribute to litter mortality. PMID:27575720

  7. Do Laboratory Mouse Females that Lose Their Litters Behave Differently around Parturition?

    PubMed

    Weber, Elin M; Hultgren, Jan; Algers, Bo; Olsson, I Anna S

    2016-01-01

    Efficiency in laboratory mouse breeding is hampered by poor reproductive performance, including the loss of entire litters shortly after birth. However, the underlying mechanisms are not yet fully understood and establishing the cause of death in laboratory mouse pups can be complicated. Newborn mouse pups are generally hidden in nests, dead pups are often eaten by the female, and the widespread practice of leaving periparturient females undisturbed complicates inspection, which may delay the discovery of pup loss. In order to efficiently prevent problems with litter loss, it is important to find key factors for survival. We investigated differences in periparturient behavior between female laboratory mice whose pups survived until weaning and females whose entire litters were lost. Video recordings of 82 primiparous females of the C57BL/6 strain or knockouts with C57BL/6 background were used. The mice were observed from 24 h before until 24 h after parturition and female behaviors coded using a pre-established ethogram. The relationship between behavior and survival was analyzed using logistic models, where litter survival was regressed on the proportion of 30-s observations with at least one occurrence of the behavior. We found that females with surviving litters performed more nest building behavior during the last 24 h before parturition (p = 0.004) and spent less time outside the nest during the entire observation period (p = 0.001). Increased litter survival was also associated with more passive maternal behaviors and the female ignoring still pups less. Females that lost their litters performed more parturition-related behaviors, suggesting prolonged labor. The results indicate that maternal behavior plays a significant role in laboratory mouse pup survival. Complications at parturition also contribute to litter mortality.

  8. Decomposition drives convergence of forest litter nutrient stoichiometry following phosphorus addition

    USGS Publications Warehouse

    van Huysen, Tiff L.; Perakis, Steven; Harmon, Mark E.

    2016-01-01

    We conclude that litter P concentrations and to some extent soil P may influence litter nutrient dynamics during decomposition, resulting in a convergence of element ratios that reflect the balance of substrate decomposition and microbial nutrient stoichiometry.

  9. WETLAND INVERTEBRATE COMMUNITY RESPONSES TO VARYING EMERGENT LITTER IN A PRAIRIE POTHOLE EMERGENT MARSH

    EPA Science Inventory

    Plant litter produced in the interior of dense emergent stands may directly or indirectly influence invertebrate communities. Low litter may provide structure and refuge to invertebrates while high litter may shade out vegetation and algae and decrease oxygen concentrations. With...

  10. Comparison of radionuclide levels in soil, sagebrush, plant litter, cryptogams, and small mammals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Landeen, D.S.

    1994-09-01

    Soil, sagebrush, plant litter, cryptogam, and small mammal samples were collected and analyzed for cesium-137, strontium-90, plutonium-238, plutonium 239/240, technetium-99, and iodine-129 from 1981 to 1986 at the US Department of Energy Hanford Site in southeastern Washington State as part of site characterization and environmental monitoring activities. Samples were collected on the 200 Areas Plateau, downwind from ongoing waste management activities. Plant litter, cryptogams, and small mammals are media that are not routinely utilized in monitoring or characterization efforts for determination of radionuclide concentrations. Studies at Hanford, other US Department of Energy sites, and in eastern Europe have indicated thatmore » plant litter and cryptogams may serve as effective ``natural`` monitors of air quality. Plant litter in this study consists of fallen leaves from sagebrush and ``cryptogams`` describes that portion of the soil crust composed of mosses, lichens, algae, and fungi. Comparisons of cesium-137 and strontium-90 concentrations in the soil, sagebrush, litter, and cryptogams revealed significantly higher (p<0.05) levels in plant litter and cryptogams. Technetium-99 values were the highest in sagebrush and litter. Plutonium-238 and 239/40 and iodine-129 concentrations never exceeded 0.8 pCi/gm in all media. No evidence of any significant amounts of any radionuclides being incorporated into the small mammal community was discovered. The data indicate that plant litter and cryptogams may be better, indicators of environmental quality than soil or vegetation samples. Augmenting a monitoring program with samples of litter and cryptogams may provide a more accurate representation of radionuclide environmental uptake and/or contamination levels in surrounding ecosystems. The results of this study may be applied directly to other radioecological monitoring conducted at other nuclear sites and to the monitoring of other pollutants.« less

  11. Changes in plant functional groups, litter quality, and soil carbon and nitrogen mineralization with sheep grazing in an Inner Mongolian Grassland

    USGS Publications Warehouse

    Barger, N.N.; Ojima, D.S.; Belnap, J.; Shiping, W.; Yanfen, W.; Chen, Z.

    2004-01-01

    This study reports on changes in plant functional group composition, litter quality, and soil C and N mineralization dynamics from a 9-year sheep grazing study in Inner Mongolia. Addressed are these questions: 1) How does increasing grazing intensity affect plant community composition? 2) How does increasing grazing intensity alter soil C and N mineralization dynamics? 3) Do changes in soil C and N mineralization dynamics relate to changes in plant community composition via inputs of the quality or quantity of litter? Grazing plots were set up near the Inner Mongolia Grassland Ecosystem Research Station (IMGERS) with 5 grazing intensities: 1.3, 2.7, 4.0, 5.3, and 6.7 sheep ha -1??yr-1. Plant cover was lower with increasing grazing intensity, which was primarily due to a dramatic decline in grasses, Carex duriuscula, and Artemisia frigida. Changes in litter mass and percentage organic C resulted in lower total C in the litter layer at 4.0 and 5.3 sheep ha-1??yr-1 compared with 2.7 sheep ha -1??yr-1. Total litter N was lower at 5.3 sheep ha-1??yr-1 compared with 2.7 sheep ha -1??yr-1. Litter C:N ratios, an index of litter quality, were significantly lower at 4.0 sheep ha-1??yr -1 relative to 1.3 and 5.3 sheep ha-1??yr -1. Cumulative C mineralized after 16 days decreased with increasing grazing intensity. In contrast, net N mineralization (NH4+ + NO3-) after a 12-day incubation increased with increasing grazing intensity. Changes in C and N mineralization resulted in a narrowing of CO2-C:net Nminratios with increasing grazing intensity. Grazing explained 31% of the variability in the ratio of CO 2-C:net Nmin. The ratio of CO2-C:net N min was positively correlated with litter mass. Furthermore, there was a positive correlation between litter mass and A. frigida cover. Results suggest that as grazing intensity increases, microbes become more C limited resulting in decreased microbial growth and demand for N.

  12. Warming magnifies predation and reduces prey coexistence in a model litter arthropod system.

    PubMed

    Thakur, Madhav P; Künne, Tom; Griffin, John N; Eisenhauer, Nico

    2017-03-29

    Climate warming can destabilize interactions between competitors as smaller organisms gain advantages in warmer environments. Whether and how warming-induced effects on competitive interactions are modified by predation remains unknown. We hypothesized that predation will offset the competitive advantage of smaller prey species in warmer environments because of their greater vulnerability to predation. To test this, we assembled a litter arthropod community with two Collembola species ( Folsomia candida and Proisotoma minuta ) of different body sizes across a temperature gradient (three thermal environments) and in the presence and absence of predatory mites. Predatory mites reduced Collembola coexistence with increasing temperatures. Contradicting our hypothesis, the larger prey species always outperformed the smaller prey species in warmer environments with predators. Larger prey probably benefited as they expressed a greater trait (body length) plasticity to warming. Warming can thus magnify predation effects and reduce the probability of prey coexistence. © 2017 The Author(s).

  13. Biocrude oils from the fast pyrolysis of poultry litter and hardwood

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Agblevor, F.A., E-mail: Fagblevo@vt.ed; Beis, S.; Kim, S.S.

    2010-02-15

    The safe and economical disposal of poultry litter is becoming a major problem for the USA poultry industry. Current disposal methods such as land application and feeding to cattle are now under pressure because of pollution of water resources due to leaching, runoffs and concern for mad cow disease contamination of the food chain. Incineration or combustion is potentially applicable to large scale operations, but for small scale growers and EPA non-attainment areas, this is not a suitable option because of the high cost of operation. Thus, there is a need for developing appropriate technologies to dispose poultry litter. Poultrymore » litters from broiler chicken and turkey houses, as well as bedding material were converted into biocrude oil in a fast pyrolysis fluidized bed reactor. The biocrude oil yields were relatively low ranging from 36 wt% to 50 wt% depending on the age and bedding material content of the litter. The bedding material (which was mostly hardwood shavings) biocrude oil yield was 63 wt%. The higher heating value (HHV) of the poultry litter biocrude oils ranged from 26 MJ/kg to 29 MJ/kg while that of the bedding material was 24 MJ/kg. The oils had relatively high nitrogen content ranging from 4 wt% to 8 wt%, very low sulfur (<1 wt%) content and high viscosity. The viscosities of the oils appeared to be a function of both the source of litter and the pyrolysis temperature. The biochar yield ranged from 27 wt% to 40 wt% depending on the source, age and composition of the poultry litter. The biochar ash content ranged from 24 wt% to 54 wt% and was very rich in inorganic components such as potassium and phosphorous.« less

  14. Thermal Inactivation of Desiccation-Adapted Salmonella spp. in Aged Chicken Litter

    PubMed Central

    Chen, Zhao; Diao, Junshu; Dharmasena, Muthu; Ionita, Claudia; Rieck, James

    2013-01-01

    Thermal inactivation of desiccation-adapted Salmonella spp. in aged chicken litter was investigated in comparison with that in a nonadapted control to examine potential cross-tolerance of desiccation-adapted cells to heat treatment. A mixture of four Salmonella serovars was inoculated into the finished compost with 20, 30, 40, and 50% moisture contents for a 24-h desiccation adaptation. Afterwards, the compost with desiccation-adapted cells was inoculated into the aged chicken litter with the same moisture content for heat treatments at 70, 75, 80, 85, and 150°C. Recovery media were used to allow heat-injured cells to resuscitate. A 5-log reduction in the number of the desiccation-adapted cells in aged chicken litter with a 20% moisture content required >6, >6, ∼4 to 5, and ∼3 to 4 h of exposure at 70, 75, 80, and 85°C, respectively. As a comparison, a 5-log reduction in the number of nonadapted control cells in the same chicken litter was achieved within ∼1.5 to 2, ∼1 to 1.5, ∼0.5 to 1, and <0.5 h at 70, 75, 80, and 85°C, respectively. The exposure time required to obtain a 5-log reduction in the number of desiccation-adapted cells gradually became shorter as temperature and moisture content were increased. At 150°C, desiccation-adapted Salmonella cells survived for 50 min in chicken litter with a 20% moisture content, whereas control cells were detectable by enrichment for only 10 min. Our results demonstrated that the thermal resistance of Salmonella in aged chicken litter was increased significantly when the cells were adapted to desiccation. This study also validated the effectiveness of thermal processing being used for producing chicken litter free of Salmonella contamination. PMID:24014540

  15. Thermal inactivation of desiccation-adapted Salmonella spp. in aged chicken litter.

    PubMed

    Chen, Zhao; Diao, Junshu; Dharmasena, Muthu; Ionita, Claudia; Jiang, Xiuping; Rieck, James

    2013-11-01

    Thermal inactivation of desiccation-adapted Salmonella spp. in aged chicken litter was investigated in comparison with that in a nonadapted control to examine potential cross-tolerance of desiccation-adapted cells to heat treatment. A mixture of four Salmonella serovars was inoculated into the finished compost with 20, 30, 40, and 50% moisture contents for a 24-h desiccation adaptation. Afterwards, the compost with desiccation-adapted cells was inoculated into the aged chicken litter with the same moisture content for heat treatments at 70, 75, 80, 85, and 150°C. Recovery media were used to allow heat-injured cells to resuscitate. A 5-log reduction in the number of the desiccation-adapted cells in aged chicken litter with a 20% moisture content required >6, >6, ∼4 to 5, and ∼3 to 4 h of exposure at 70, 75, 80, and 85°C, respectively. As a comparison, a 5-log reduction in the number of nonadapted control cells in the same chicken litter was achieved within ∼1.5 to 2, ∼1 to 1.5, ∼0.5 to 1, and <0.5 h at 70, 75, 80, and 85°C, respectively. The exposure time required to obtain a 5-log reduction in the number of desiccation-adapted cells gradually became shorter as temperature and moisture content were increased. At 150°C, desiccation-adapted Salmonella cells survived for 50 min in chicken litter with a 20% moisture content, whereas control cells were detectable by enrichment for only 10 min. Our results demonstrated that the thermal resistance of Salmonella in aged chicken litter was increased significantly when the cells were adapted to desiccation. This study also validated the effectiveness of thermal processing being used for producing chicken litter free of Salmonella contamination.

  16. Biocrude oils from the fast pyrolysis of poultry litter and hardwood.

    PubMed

    Agblevor, F A; Beis, S; Kim, S S; Tarrant, R; Mante, N O

    2010-02-01

    The safe and economical disposal of poultry litter is becoming a major problem for the USA poultry industry. Current disposal methods such as land application and feeding to cattle are now under pressure because of pollution of water resources due to leaching, runoffs and concern for mad cow disease contamination of the food chain. Incineration or combustion is potentially applicable to large scale operations, but for small scale growers and EPA non-attainment areas, this is not a suitable option because of the high cost of operation. Thus, there is a need for developing appropriate technologies to dispose poultry litter. Poultry litters from broiler chicken and turkey houses, as well as bedding material were converted into biocrude oil in a fast pyrolysis fluidized bed reactor. The biocrude oil yields were relatively low ranging from 36 wt% to 50 wt% depending on the age and bedding material content of the litter. The bedding material (which was mostly hardwood shavings) biocrude oil yield was 63 wt%. The higher heating value (HHV) of the poultry litter biocrude oils ranged from 26 MJ/kg to 29 MJ/kg while that of the bedding material was 24 MJ/kg. The oils had relatively high nitrogen content ranging from 4 wt% to 8 wt%, very low sulfur (<1 wt%) content and high viscosity. The viscosities of the oils appeared to be a function of both the source of litter and the pyrolysis temperature. The biochar yield ranged from 27 wt% to 40 wt% depending on the source, age and composition of the poultry litter. The biochar ash content ranged from 24 wt% to 54 wt% and was very rich in inorganic components such as potassium and phosphorous.

  17. Decreasing phosphorus runoff losses from land-applied poultry litter with dietary modifications and alum addition.

    PubMed

    Smith, Douglas R; Moore, P A; Miles, D M; Haggard, B E; Daniel, T C

    2004-01-01

    Phosphorus (P) losses from pastures fertilized with poultry litter contribute to the degradation of surface water quality in the United States. Dietary modification and manure amendments may reduce potential P runoff losses from pastures. In the current study, broilers were fed a normal diet, phytase diet, high available phosphorus (HAP) corn diet, or HAP corn + phytase diet. Litter treatments were untreated control and alum added at 10% by weight between flocks. Phytase and HAP corn diets reduced litter dissolved P content in poultry litter by 10 and 35%, respectively, compared with the normal diet (789 mg P kg(-1)). Alum treatment of poultry litter reduced the amount of dissolved P by 47%, while a 74% reduction was noted after alum treatment of litter from the HAP corn + phytase diet. The P concentrations in runoff water were highest from plots receiving poultry litter from the normal diet, whereas plots receiving poultry litter from phytase and HAP corn diets had reduced P concentrations. The addition of alum to the various poultry litters reduced P runoff by 52 to 69%; the greatest reduction occurred when alum was used in conjunction with HAP corn and phytase. This study demonstrates the potential added benefits of using dietary modification in conjunction with manure amendments in poultry operations. Integrators and producers should consider the use of phytase, HAP corn, and alum to reduce potential P losses associated with poultry litter application to pastures.

  18. Considerations on the effects of tidal regimes in the movement of floating litter in an estuarine environment: Case study of the estuarine system of Santos-São Vicente, Brazil.

    PubMed

    Fernandino, Gerson; Elliff, Carla Isobel; Frutuoso, Gabriela Amado; Silva, Eric Vinícius Nascimento Malaquias da; Gama, Guilherme Santiago; Sousa, João Henrique de Oliveira; Silva, Iracema Reimão

    2016-09-15

    Floating litter in the estuarine system of Santos-São Vicente is common and is part of day-to-day activities of various users of the area. The objective of the present study was to carry out a quali-quantitative evaluation of the occurrence of floating litter, to infer their sources, and to identify environmental factors that are likely to control occurrence and distribution, with particular emphasis on the effects of tidal regimes. Six sampling stations were selected along the aforementioned estuary and visited monthly between July 2010 and January 2012. Floating litter was counted from a fixed sampling station. Plastics prevailed (89.64%) and their main source was domestic activities (55.41%). More litter was found during ebb spring tides, with higher concentrations obeying confluence patterns of the estuary's channels. Results indicated that occurrence can be attributed to the deficiency in basic sewage system in the area and the deliberate disposal into the estuary by the local population. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Age-related effects of body mass on fertility and litter size in roe deer.

    PubMed

    Flajšman, Katarina; Jerina, Klemen; Pokorny, Boštjan

    2017-01-01

    We analysed effects of females' body mass and age on reproductive capacity of European roe deer (Capreolus capreolus) in a large sample set of 1312 females (305 yearlings and 1007 adults), hunted throughout Slovenia, central Europe, in the period 2013-2015. Body mass positively affected probability of ovulation and potential litter size (number of corpora lutea), although its effect was more pronounced in yearlings than in adults. Between age groups, we found clear differences in responses of both reproductive parameters to body mass which influences primarily reproductive performance of younger, and in particular, lighter individuals: at the same body mass yearlings would at average have smaller litters than adults, and at lower body mass also young to middle-aged adults would have smaller litters than old ones. In addition, while yearlings have to reach a critical threshold body mass to attain reproductive maturity, adult females are fertile (produce ova) even at low body mass. However, at higher body mass also younger individuals shift their efforts into the reproduction, and after reaching an age-specific threshold the body mass does not have any further effects on the reproductive output of roe deer females. Increased reproductive capacity at more advanced age, combined with declining body mass suggests that old does allocate more of their resources in reproduction than in body condition.

  20. Age-related effects of body mass on fertility and litter size in roe deer

    PubMed Central

    Jerina, Klemen; Pokorny, Boštjan

    2017-01-01

    We analysed effects of females’ body mass and age on reproductive capacity of European roe deer (Capreolus capreolus) in a large sample set of 1312 females (305 yearlings and 1007 adults), hunted throughout Slovenia, central Europe, in the period 2013–2015. Body mass positively affected probability of ovulation and potential litter size (number of corpora lutea), although its effect was more pronounced in yearlings than in adults. Between age groups, we found clear differences in responses of both reproductive parameters to body mass which influences primarily reproductive performance of younger, and in particular, lighter individuals: at the same body mass yearlings would at average have smaller litters than adults, and at lower body mass also young to middle-aged adults would have smaller litters than old ones. In addition, while yearlings have to reach a critical threshold body mass to attain reproductive maturity, adult females are fertile (produce ova) even at low body mass. However, at higher body mass also younger individuals shift their efforts into the reproduction, and after reaching an age-specific threshold the body mass does not have any further effects on the reproductive output of roe deer females. Increased reproductive capacity at more advanced age, combined with declining body mass suggests that old does allocate more of their resources in reproduction than in body condition. PMID:28403161