Challenges of reforestation in a water limited world under climate change

NASA Astrophysics Data System (ADS)

Mátyás, Csaba; Sun, Ge

2014-05-01

The debate on the ecological benefits of planted forests at the sensitive lower edge of the closed forest belt (at the "xeric limits") is still unresolved. Forests sequester atmospheric carbon dioxide, control water erosion and dust storms, reduce river sedimentation, and mitigate small floods. However, planting trees in areas previously predominantly occupied by grassland or agriculture can dramatically alter the energy and water balance at multiple scales. The forest/grassland transition zone is especially vulnerable to projected drastic temperature and precipitation shifts under future climate change and variability due to its high ecohydrological sensitivity. The study investigates some of the relevant aspects of the ecological and climatic role of plantation forests and potential impacts at the dryland edges of the temperate zone, using case studies from three countries/regions on three continents. We found that, contrary to popular expectations, the effect of forest cover on regional climate might be limited and the influence of reforestation on water resources might turn into negative. Planted forests generally reduce stream flow and lower groundwater table level because of higher water use than previous land cover types. Increased evaporation potential due to global warming and/or extreme drought events likely reduce areas that are appropriate for tree growth and forest establishment. Ecologically conscious forest policy on management, silviculture and reforestation planning requires the consideration of local hydrologic conditions, future climatic conditions, and also of non-forest alternatives of land use. Keywords: drylands, xeric limits, trailing limits, ecohydrology, climate forcing, land use change, forest policy

Forest fires impact in semi arid lands in Algeria, analysis and followed of desertification by using remote sensing and GIS

NASA Astrophysics Data System (ADS)

Zegrar, Ahmed

The Forest in steppe present ecological diversity, and seen climatic unfavourable conditions in zone and impact of forest fires; we notes deterioration of physical environment particularly, deterioration of natural forest. This deterioration of forests provokes an unbalance of environment witch provokes a process of deterioration advanced in the ultimate stadium is desertification. By elsewhere, where climatic conditions are favourable, the fire is an ecological and acted agent like integral part of evolution of the ecosystems, the specific regeneration of plants are influenced greatly by the regime of fire (season of fire, intensity, interval), who leads to the recuperation of the vegetation of meadow- fire. In this survey we used the pictures ALSAT-1 for detection of zones with risk of forest fire and their impact on the naturals forests in region of Tlemcen. A thematic detailed analysis of forests well attended ecosystems some processing on the picture ALSAT-1, we allowed to identify and classifying the forests in there opinion components flowers. we identified ampleness of fire on this zone also. Some parameters as the slope, the proximity to the road and the forests formations were studied in the goal of determining the zones to risk of forest fire. A crossing of diaper of information in a SIG according to a very determined logic allowed to classify the zones in degree of risk of fire in a middle arid in a forest zone not encouraging the regeneration on the other hand permitting the installation of cash of steppe which encourages the desertification.

Response of herbaceous plant community diversity and composition to overstorey harvest within riparian management zones in Northern Hardwoods

Treesearch

Eric K. Zenner; Michelle A. Martin; Brian J. Palik; Jerilynn E. Peck; Charles R. Blinn

2013-01-01

Partial timber harvest within riparian management zones (RMZs) may permit active management of riparian forests while protecting stream ecosystems, but impacts on herbaceous communities are poorly understood. We compared herbaceous plant community abundance, diversity and composition in RMZs along small streams in northern Minnesota, USA, among four treatments before...

Variations of soil microbial community structures beneath broadleaved forest trees in temperate and subtropical climate zones

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

Yang, Sihang; Zhang, Yuguang; Cong, Jing

Global warming has shifted climate zones poleward or upward. Furthermore, understanding the responses and mechanism of microbial community structure and functions relevant to natural climate zone succession is challenged by the high complexity of microbial communities. Here, we examined soil microbial community in three broadleaved forests located in the Wulu Mountain (WLM, temperate climate), Funiu Mountain (FNM, at the border of temperate and subtropical climate zones), or Shennongjia Mountain (SNJ, subtropical climate). Although plant species richness decreased with latitudes, the microbial taxonomic α-diversity increased with latitudes, concomitant with increases in soil total and available nitrogen and phosphorus contents. Phylogenetic NRImore » (Net Relatedness Index) values increased from 0.718 in temperate zone (WLM) to 1.042 in subtropical zone (SNJ), showing a shift from over dispersion to clustering likely caused by environmental filtering such as low pH and nutrients. Similarly, taxonomybased association networks of subtropical forest samples were larger and tighter, suggesting clustering. In contrast, functional α-diversity was similar among three forests, but functional gene networks of the FNM forest significantly (P < 0.050) differed from the others. A significant correlation (R = 0.616, P < 0.001) between taxonomic and functional β-diversity was observed only in the FNM forest, suggesting low functional redundancy at the border of climate zones. Using a strategy of space-fortime substitution, we predict that poleward climate range shift will lead to decreased microbial taxonomic α-diversities in broadleaved forest.« less

Variations of soil microbial community structures beneath broadleaved forest trees in temperate and subtropical climate zones

DOE PAGES

Yang, Sihang; Zhang, Yuguang; Cong, Jing; ...

2017-02-10

Global warming has shifted climate zones poleward or upward. Furthermore, understanding the responses and mechanism of microbial community structure and functions relevant to natural climate zone succession is challenged by the high complexity of microbial communities. Here, we examined soil microbial community in three broadleaved forests located in the Wulu Mountain (WLM, temperate climate), Funiu Mountain (FNM, at the border of temperate and subtropical climate zones), or Shennongjia Mountain (SNJ, subtropical climate). Although plant species richness decreased with latitudes, the microbial taxonomic α-diversity increased with latitudes, concomitant with increases in soil total and available nitrogen and phosphorus contents. Phylogenetic NRImore » (Net Relatedness Index) values increased from 0.718 in temperate zone (WLM) to 1.042 in subtropical zone (SNJ), showing a shift from over dispersion to clustering likely caused by environmental filtering such as low pH and nutrients. Similarly, taxonomybased association networks of subtropical forest samples were larger and tighter, suggesting clustering. In contrast, functional α-diversity was similar among three forests, but functional gene networks of the FNM forest significantly (P < 0.050) differed from the others. A significant correlation (R = 0.616, P < 0.001) between taxonomic and functional β-diversity was observed only in the FNM forest, suggesting low functional redundancy at the border of climate zones. Using a strategy of space-fortime substitution, we predict that poleward climate range shift will lead to decreased microbial taxonomic α-diversities in broadleaved forest.« less

Direct effects of temperature on forest nitrogen cycling revealed through analysis of long-term watershed records

Treesearch

E.N. Jack Brookshire; Stefan Gerber; Jackson R. Webster; James M. Vose; Wayne T. Swank

2010-01-01

The microbial conversion of organic nitrogen (N) to plant available forms is a critical determinant of plant growth and carbon sequestration in forests worldwide. In temperate zones, microbial activity is coupled to variations in temperature, yet at the ecosystem level, microbial N mineralization seems to play a minor role in determining patterns of N loss. Rather, N...

Plant management and biodiversity conservation in Náhuatl homegardens of the Tehuacán Valley, Mexico

PubMed Central

2013-01-01

Background The Tehuacán Valley is one of the areas of Mesoamerica with the oldest history of plant management. Homegardens are among the most ancient management systems that currently provide economic benefits to people and are reservoirs of native biodiversity. Previous studies estimated that 30% of the plant richness of homegardens of the region are native plant species from wild populations. We studied in Náhuatl communities the proportion of native plant species maintained in homegardens, hypothesizing to find a proportion similar to that estimated at regional level, mainly plant resources maintained for edible, medicinal and ornamental purposes. Methods We analysed the composition of plant species of homegardens and their similarity with surrounding Cloud Forest (CF), Tropical Rainforest (TRF), Tropical Dry forest (TDF), and Thorn-Scrub Forest (TSF). We determined density, frequency and biomass of plant species composing homegardens and forests through vegetation sampling of a total of 30 homegardens and nine plots of forests, and documented ethnobotanical information on use, management, and economic benefits from plants maintained in homegardens. Results A total of 281 plant species was recorded with 12 use categories, 115 ornamental, 92 edible, and 50 medicinal plant species. We recorded 49.8 ± 23.2 (average ± S.D.) woody plant species (shrubs and trees) per homegarden. In total, 34% species are native to the Tehuacán Valley and nearly 16% are components of the surrounding forests. A total of 176 species were cultivated through seeds, vegetative propagules or transplanted entire individual plants, 71 tolerated, and 23 enhanced. The highest species richness and diversity were recorded in homegardens from the CF zone (199 species), followed by those from the TRF (157) and those from the TDF (141) zones. Conclusion Homegardens provide a high diversity of resources for subsistence of local households and significantly contribute to conservation of native biodiversity. The highest diversity was recorded in homegardens where the neighbouring forests had the least diversity, suggesting that management of homegardens aims at compensating scarcity of naturally available plant resources. Cultivated species were markedly more abundant than plants under other management forms. Diversity harboured and management techniques make homegardens keystones in strategies for regional biodiversity conservation. PMID:24195962

[Distribution pattern of rare plants along riparian zone and its implication for conservation in Shennongjia area].

PubMed

Jiang, Mingxi; Deng, Hongbing; Cai, Qinghua

2002-11-01

Due to the importance of riparian zone in maintaining and protecting regional biodiversity, more and more ecologists paid their attentions to riparian zone, and had been aware of the important effects of riparian zone in basic study and practical management. In this study, forty sampling belts (10 m x 100 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia area were selected to investigate the riparian vegetation and rare plants. Fourteen species of rare plants were found in riparian zone, accounting for 42.4% of total rare plant species in Shennongjia area. The main distribution range of the fourteen rare plant species was the mixed evergreen and deciduous broadleaved forest at elevation of 1200-1800 m, where species diversity of plant community was the maximum at the moderate elevation. Fourteen rare plant species could be divided into three groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation group. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out the important function of riparian zone on rare plant species protection.

Diet selectivity in a terrestrial forest invertebrate, the Auckland tree wētā, across three habitat zones.

PubMed

Brown, Matthew B G J; Gemmill, Chrissen E C; Miller, Steven; Wehi, Priscilla M

2018-03-01

Insects are important but overlooked components of forest ecosystems in New Zealand. For many insect species, information on foraging patterns and trophic relationships is lacking. We examined diet composition and selectivity in a large-bodied insect, the Auckland tree wētā Hemideina thoracica , in three habitat zones in a lowland New Zealand forest. We asked whether H. thoracica selectively forage from available plant food sources, and whether these choices were lipid-rich compared to nonpreferred available plants. We also identified the proportion of invertebrates in their frass as a proxy for omnivory. From reconnaissance plot sampling, together with fecal fragment analysis, we report that more than 93% of individual tree wētā had eaten invertebrates before capture. Additionally, wētā in the highest elevation hillslope habitat zone consumed significantly fewer species of plants on average than wētā on the low-elevation terrace habitat. Upper hillslope wētā also had the highest average number of invertebrate fragments in their frass, significantly more than wētā in the low-elevation terrace habitat zone. Wētā showed high variability in the consumption of fruit and seeds across all habitat zones. Generally, we did not observe diet differences between the sexes (although it appears that male wētā in the mid-hillslope habitat ate fruits and seeds more voraciously than females), suggesting that the sexes have similar niche breadths and display similar degrees of omnivorous behavior. Extraction of leaf lipids demonstrated a range of lipid content values in available plants, and Ivlev's Electivity Index indicated that plant species which demonstrated high electivity tended to have higher concentrations of lipids in their leaves. Our findings indicate that H. thoracica forage omnivorously and selectively, and hence play multiple roles in native ecosystems and food webs.

Climate-based seed zones for Mexico: guiding reforestation under observed and projected climate change

Treesearch

Dante Castellanos-Acuña; Kenneth W. Vance-Borland; J. Bradley St. Clair; Andreas Hamann; Javier López-Upton; Erika Gómez-Pineda; Juan Manuel Ortega-Rodríguez; Cuauhtémoc Sáenz-Romero

2018-01-01

Seed zones for forest tree species are a widely used tool in reforestation programs to ensure that seedlings are well adapted to their planting environments. Here, we propose a climate-based seed zone system for Mexico to address observed and projected climate change. The proposed seed zone classification is based on bands of climate variables often related to genetic...

Native plant conservation partnership with BLM and development of seed zones for restoration

USDA-ARS?s Scientific Manuscript database

Native forest and rangeland plant communities in the arid Western U.S. are increasingly threatened by overgrazing, uncharacteristically frequent wildfires, invasive weeds, and climate change. As a result, the need for conservation of native plant materials and their use in restoration has increased....

Acute and long-term effects of irradiation on pine (Pinus silvestris) strands post-Chernobyl.

PubMed

Arkhipov, N P; Kuchma, N D; Askbrant, S; Pasternak, P S; Musica, V V

1994-12-11

The effect of ionizing irradiation on the viability of pine stands after the fallout from the damaged nuclear energy plant at Chernobyl (ChNPP) was shown within the territory of the 10-km zone. During the period 1986-1991, irradiated and damaged forest stands, so-called 'red forest', located in this area were systematically classified by observation. Mortality rate, re-establishment, development of tree canopies, reproduction anomalies and stand viability were shown to be dependent on absorbed irradiation dose, on the age of the stand and on forest composition. For pine stands in the acutely affected zone, doses of more than 60 Gy resulted in a massive mortality and no regeneration of pine trees since 1987. The injured trees had burned or had dried-up. The drying process was accelerated by a massive production of pathogenic insects invading the dying trees. Specifically, irradiation doses of 10-60 Gy, 1-10 Gy and 0.1-1 Gy caused high, medium and low injury to the forest stands, respectively. Doses of less than 0.1 Gy did not cause any visible damage to the trees. In 1987, repair processes were displayed by the tree canopies and practically the entire viability of the forest stands had recovered except for trees in the acute and highly affected zones. The young forest was reestablished in the same place as the perished trees and new pine saplings were planted on the reclaimed areas.

Co-regulation of photosynthetic capacity by nitrogen, phosphorus and magnesium in a subtropical Karst forest in China.

PubMed

Wang, Jing; Wen, Xuefa; Zhang, Xinyu; Li, Shenggong; Zhang, Da-Yong

2018-05-09

Leaf photosynthetic capacity is mainly constrained by nitrogen (N) and phosphorus (P). Little attention has been given to the photosynthetic capacity of mature forests with high calcium (Ca) and magnesium (Mg) in the Karst critical zone. We measured light-saturated net photosynthesis (A sat ), photosynthetic capacity (maximum carboxylation rate [V cmax ], and maximum electron transport rate [J max ]) as well as leaf nutrient contents (N, P, Ca, Mg, potassium [K], and sodium [Na]), leaf mass per area (LMA), and leaf thickness (LT) in 63 dominant plants in a mature subtropical forest in the Karst critical zone in southwestern China. Compared with global data, plants showed higher A sat for a given level of P. V cmax and J max were mainly co-regulated by N, P, Mg, and LT. The ratios of V cmax to N or P, and J max to N or P were significantly positively related to Mg. We speculate that the photosynthetic capacity of Karst plants can be modified by Mg because Mg can enhance photosynthetic N and P use efficiency.

Plant community classification for alpine vegetation on the Beaverhead National Forest, Montana

Treesearch

Stephen V. Cooper; Peter Lesica; Deborah Page-Dumroese

1997-01-01

Vegetation of the alpine zone of eight mountain ranges in southwestern Montana was classified using IWINSPAN, DECORAN, and STRATA-algorithms embedded within the U.S. Forest Service Northern Region's ECADS (ecological classification and description system) program. Quantitative estimates of vegetation and soil attributes were sampled from 138 plots. Vegetation...

Plant association and management guide for the Pacific silver fir zone Gifford Pinchot National Forest.

Treesearch

Dale G. Brockway; Christopher Topik; Miles A. Hemstrom; William H. Emmingham

1983-01-01

The study of plant communities provides useful information about the environment in which they occur. Communities are a product of long-term interaction between factors in the physical environment and the organisms present. Environmental factors such as temperature, moisture, light and nutrients act as selective influences on plant populations, favoring species best...

Modelling the impact of mulching the soil with plant remains on water regime formation, crop yield and energy costs in agricultural ecosystems

NASA Astrophysics Data System (ADS)

Gusev, Yeugeniy M.; Dzhogan, Larisa Y.; Nasonova, Olga N.

2018-02-01

The model MULCH, developed by authors previously for simulating the formation of water regime in an agricultural field covered by straw mulch layer, has been used for the comparative evaluation of the efficiency of four agricultural cultivation technologies, which are usually used for wheat production in different regions of Russia and Ukraine. It simulates the dynamics of water budget components in a soil rooting zone at daily time step from the beginning of spring snowmelt to the beginning of the period with stable negative air temperatures. The model was designed for estimation of mulching efficiency in terms of increase in plant water supply and crop yield under climatic and soil conditions of the steppe and forest-steppe zones. It is used for studying the mulching effect on some characteristics of water regime and yield of winter wheat growing at specific sites located in semi-arid and arid regions of the steppe and forest-steppe zones of the eastern and southern parts of the East-European (Russian) plain. In addition, a previously developed technique for estimating the energetic efficiency of various agricultural technologies with accounting for their impact on changes in soil energy is applied for the comparative evaluation of the efficiency of four agricultural cultivation technologies, which are usually used for wheat production in different regions of the steppe and forest-steppe zones of the European Russia: (1) moldboard tillage of soil without irrigation, (2) moldboard tillage of soil with irrigation, (3) subsurface cultivation, and (4) subsurface cultivation with mulching the soil with plant remains.

The phyllophagous of woody plants of genus Ulmus in protective plantings of arid zone

NASA Astrophysics Data System (ADS)

Belitskaya, M. N.; Gribust, I. R.; Nefed'eva, E. E.; Filimonova, O. S.; Golovanova, M. A.

2018-01-01

Creating of long-lasting, normally developing plantings on the urbanized territories in the arid zones is difficult. The main tree species are elm (Fam. Ulmaceae - more than 70% of tree composition). They have a high drought and salt tolerance, rapid growth. They are widely used in the creation of artificial forest plantings in steppes and deserts. The main part of the plantations was created in the 50-60 years of 20th century. Today the aging of plants is observing. Trees of this age lose their physiological and decorative potential as well as resistance to pests under intensive anthropogenic impact. At the forest pathology research about 90 % of the plants of elm species of plantings of various types and categories were identified to be in poor condition. Leaf-eating pests play an active role in the deterioration of their sanitary state. Xanthogaleruca luteola (Müller, 1766), Cladius ulmi (Linnaeus, 1758), and Aproceros leucopoda (Takeuchi, 1939) have a special harmfulness as well as the regularity of the local centers among the mass phyllophagous of plants of the family. The last two species were discovered in artificial plantations for the first time. The destructive effect of those pests on certain types of elm plants is uneven.

The role of vegetation in the stability of forested slopes

Treesearch

Robert R. Ziemer

1981-01-01

Summary - Vegetation helps stabilize forested slopes by providing root strength and by modifying the saturated soil water regime. Plant roots can anchor through the soil mass into fractures in bedrock, can cross zones of weakness to more stable soil, and can provide interlocking long fibrous binders within a weak soil mass. In Mediterranean-type climates, having warm...

Acid precipitation: compositional changes during throughfall; soil water. Technical completion report

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

Klein, R.

1984-12-01

Lysimeters were installed at two soil depths within each of the three major ecosystems on Camels Hump Mountain. Collections were made weekly during the frost-free season of 1982 and 1983. Samples were analyzed for pH, conductivity, and a broad range of metals, anionic and cationic constituents, and for other physical properties. The findings included: soil solutions obtained from the upper-elevations in a northern coniferous forest zone are significantly more acidic than those from the lower elevation hardwood forest zone; soil solutions for all ecological zones are more acidic in the spring during and shortly after snowmelt than they are latermore » in the frost free-season; aluminum in soil solutions from the upper elevations is present in concentrations known to be phytotoxic to seedlings of forest trees and to groundcover plants; cadmium, Pb, and Zn are, in the spring, present in concentrations that are close to being phytotoxic; there are changes in the ratios of divalent cations to specific metals during the season and as functions of altitude and forest zones; nitrate concentration in soil water are also elevation- and time dependent.« less

Ecological zones in the Southern Appalachians: first approximation

Treesearch

Steven A. Simon; Thomas K. Collins; Gary L. Kauffman; W. Henry McNab; Christopher J. Ulrey

2005-01-01

Forest environments of the Southern Appalachian Mountains and their characteristic plant communities are among the most varied in the Eastern United States. Considerable data are available on the distribution of plant communities relative to temperature and moisture regimes, but not much information on fertility as an environmental influence has been published; nor has...

Predicting Plant-Accessible Water in the Critical Zone: Mountain Ecosystems in a Mediterranean Climate

NASA Astrophysics Data System (ADS)

Klos, P. Z.; Goulden, M.; Riebe, C. S.; Tague, C.; O'Geen, A. T.; Flinchum, B. A.; Safeeq, M.; Conklin, M. H.; Hart, S. C.; Asefaw Berhe, A.; Hartsough, P. C.; Holbrook, S.; Bales, R. C.

2017-12-01

Enhanced understanding of subsurface water storage, and the below-ground architecture and processes that create it, will advance our ability to predict how the impacts of climate change - including drought, forest mortality, wildland fire, and strained water security - will take form in the decades to come. Previous research has examined the importance of plant-accessible water in soil, but in upland landscapes within Mediterranean climates the soil is often only the upper extent of subsurface water storage. We draw insights from both this previous research and a case study of the Southern Sierra Critical Zone Observatory to: define attributes of subsurface storage, review observed patterns in its distribution, highlight nested methods for its estimation across scales, and showcase the fundamental processes controlling its formation. We observe that forest ecosystems at our sites subsist on lasting plant-accessible stores of subsurface water during the summer dry period and during multi-year droughts. This indicates that trees in these forest ecosystems are rooted deeply in the weathered, highly porous saprolite, which reaches up to 10-20 m beneath the surface. This confirms the importance of large volumes of subsurface water in supporting ecosystem resistance to climate and landscape change across a range of spatiotemporal scales. This research enhances the ability to predict the extent of deep subsurface storage across landscapes; aiding in the advancement of both critical zone science and the management of natural resources emanating from similar mountain ecosystems worldwide.

Environmental Fate and Aquatic Impacts of Hexzinone Applied at a High Rate for Planting Site Preparation

Treesearch

Jerry L. Michael

1998-01-01

Most environmental fate and impact concerns associated with the use of forest herbicides are related to offsite movement during and after application. The environmental fate and ecosystem impacts of forest herbicides are governed by movement and transformation in the atmosphere, above ground vegetation, soil surface, soil rooting zone, surface water, and groundwater....

Climate Change Impacts on Fort Bragg, NC

DTIC Science & Technology

2013-10-15

28 5.8 Soil erosion at Fort Bragg...Rust fungi that attack the plant appear worse during wet sum- mers. Since the summers may be wetter at Fort Bragg, it may become more difficult to...drop zones. This plant requires frequent fires on its sandy soils . All of these species are associated with the Longleaf pine forests of the

Riparian restoration in the Southwest: Species selection, propagation, planting methods, and case studies

Treesearch

David Dreesen; John Harrington; Tom Subirge; Pete Stewart; Greg Fenchel

2002-01-01

Riparian plant communities, though small in overall area, are among the most valuable natural areas in the Southwest. The causes of degradation of southwestern riparian zones range from excessive cattle and elk grazing in montane watersheds to invasive woody exotic species and lack of natural flooding in the cottonwood forests, "bosque," of low elevation...

Root colonization and spore abundance of arbuscular mycorrhizal fungi in distinct successional stages from an Atlantic rainforest biome in southern Brazil.

PubMed

Zangaro, Waldemar; Rostirola, Leila Vergal; de Souza, Priscila Bochi; de Almeida Alves, Ricardo; Lescano, Luiz Eduardo Azevedo Marques; Rondina, Artur Berbel Lírio; Nogueira, Marco Antonio; Carrenho, Rosilaine

2013-04-01

The influence of plant functional groups and moderate seasonality on arbuscular mycorrhizal (AM) fungal status (root colonization and spore density) was investigated during 13 consecutive months in a chronosequence of succession in southern Brazil, consisting of grassland field, scrub vegetation, secondary forest and mature forest, in a region of transition from tropical to subtropical zones. AM root colonization and spore density decreased with advancing succession and were highest in early successional sites with grassland and scrub vegetation, intermediary in the secondary forest and lowest in the mature forest. They were little influenced by soil properties, but were sufficiently influenced by the fine root nutrient status and fine root traits among different functional plant groups. AM root colonization and spore density were higher during the favourable plant growth season (spring and summer) than during the less favourable plant growth season (autumn and winter). Spore density displayed significant seasonal variation at all sites, whilst root colonization displayed significant seasonal variation in grassland, scrub and secondary forest, but not in mature forest. The data suggest that (1) different plant functional groups display different relationships with AM fungi, influencing their abundance differentially; (2) plant species from early successional phases are more susceptible to AM root colonization and maintain higher AM sporulation than late successional species; (3) fine root traits and nutrient status influence these AM fungal attributes; and (4) higher AM spore production and root colonization is associated with the season of higher light incidence and temperature, abundant water in soil and higher plant metabolic activity.

A new climatic classification of afforestation in Three-North regions of China with multi-source remote sensing data

NASA Astrophysics Data System (ADS)

Zheng, Xiao; Zhu, Jiaojun

2017-01-01

Afforestation and reforestation activities achieve high attention at the policy agenda as measures for carbon sequestration in order to mitigate climate change. The Three-North Shelter Forest Program, the largest ecological afforestation program worldwide, was launched in 1978 and will last until 2050 in the Three-North regions (accounting for 42.4 % of China's territory). Shelter forests of the Three-North Shelter Forest Program have exhibited severe decline after planting in 1978 due to lack of detailed climatic classification. Besides, a comprehensive assessment of climate adaptation for the current shelter forests was lacking. In this study, the aridity index determined by precipitation and reference evapotranspiration was employed to classify climatic zones for the afforestation program. The precipitation and reference evapotranspiration with 1-km resolution were estimated based on data from the tropical rainfall measuring mission and moderate resolution imaging spectroradiometer, respectively. Then, the detailed climatic classification for the afforestation program was obtained based on the relationship between the different vegetation types and the aridity index. The shelter forests in 2008 were derived from Landsat TM in the Three-North regions. In addition, climatic zones and shelter forests were corrected by comparing with natural vegetation map and field surveys. By overlaying the shelter forests on the climatic zones, we found that 16.30 % coniferous forests, 8.21 % broadleaved forests, 2.03 % mixed conifer-broadleaved forests, and 10.86 % shrubs were not in strict accordance with the climate conditions. These results open new perspectives for potential use of remote sensing techniques for afforestation management.

Precontact vegetation and soil nutrient status in the shadow of Kohala Volcano, Hawaii

NASA Astrophysics Data System (ADS)

Chadwick, Oliver A.; Kelly, Eugene F.; Hotchkiss, Sara C.; Vitousek, Peter M.

2007-09-01

Humans colonized Hawaii about 1200 years ago and have progressively modified vegetation, particularly in mesic to dry tropical forests. We use δ 13C to evaluate the contribution of C 3 and C 4 plants to deep soil organic matter to reconstruct pre-human contact vegetation patterns along a wet to dry climate transect on Kohala Mountain, Hawaii Island. Precontact vegetation assemblages fall into three distinct zones: a wet C 3 dominated closed canopy forest where annual rainfall is > 2000 mm, a dry C 4 dominated grassland with annual rainfall < 500 mm, and a broad transition zone between these communities characterized by either C 3 trees with higher water-use efficiency than the rainforest trees or C 3 trees with a small amount of C 4 grasses intermixed. The likelihood of C 4 grass understory decreases with increasing rainfall. We show that the total concentration of rock-derived nutrients in the < 2-mm soil fraction differs in each of these vegetation zones. Nutrient losses are driven by leaching at high rainfall and by plant cycling and wind erosion at low rainfall. By contrast, nutrients are best preserved in surface soils of the intermediate rainfall zone, where rainfall supports abundant plant growth but does not contribute large amounts of water in excess of evapotranspiration. Polynesian farmers exploited these naturally enriched soils as they intensified their upland agricultural systems during the last three centuries before European contact.

Perspectives on Screening Winter-Flood-Tolerant Woody Species in the Riparian Protection Forests of the Three Gorges Reservoir

PubMed Central

Yang, Fan; Wang, Yong; Chan, Zhulong

2014-01-01

The establishment of riparian protection forests in the Three Gorges Reservoir (TGR) is an ideal measure to cope with the eco-environmental problems of the water-level fluctuation zone (WLFZ). Thus, the information for screening winter-flood-tolerant woody plant species is useful for the recovery and re-establishment of the riparian protection forests in the TGR WLFZ. Therefore, we discussed the possibilities of constructing and popularizing riparian protection forests in the TGR WLFZ from several aspects, including the woody plant species distribution in the WLFZ, the survival rate analyses of suitable candidate woody species under controlled flooding conditions, the survival rate investigation of some woody plant species planted in the TGR WLFZ, and the physiological responses of some woody plant species during the recovery stage after winter floods. The results of woody species investigation showed that most woody plant species that existed as annual seedlings in the TGR WLFZ are not suitable candidates for the riparian protection forests. However, arbor species (e.g., Salix matsudana, Populus×canadensis, Morus alba, Pterocarya stenoptera, Taxodium ascendens, and Metasequoia glyptostroboides) and shrub species (e.g., Salix variegata, Distylium chinensis, Lycium chinense, Myricaria laxiflora, and Rosa multiflora) might be considered suitable candidates for the riparian protection forests in the TGR WLFZ by survival rate analyses under controlled winter flooding conditions, and survival rate investigations of woody plant species planted in the TGR WLFZ, respectively. Physiological analyses showed that P.×canadensis, M. alba, L. chinense, and S. variegata could develop specific self-repairing mechanisms to stimulate biomass accumulation and carbohydrate synthesis via the increases in chlorophyll pigments and photosynthesis during recovery after winter floods. Our results suggested these woody plant species could endure the winter flooding stress and recover well, and be used as candidate for the construction of riparian protection forests in the TGR WLFZ. PMID:25265326

Perspectives on screening winter-flood-tolerant woody species in the riparian protection forests of the three gorges reservoir.

PubMed

Yang, Fan; Wang, Yong; Chan, Zhulong

2014-01-01

The establishment of riparian protection forests in the Three Gorges Reservoir (TGR) is an ideal measure to cope with the eco-environmental problems of the water-level fluctuation zone (WLFZ). Thus, the information for screening winter-flood-tolerant woody plant species is useful for the recovery and re-establishment of the riparian protection forests in the TGR WLFZ. Therefore, we discussed the possibilities of constructing and popularizing riparian protection forests in the TGR WLFZ from several aspects, including the woody plant species distribution in the WLFZ, the survival rate analyses of suitable candidate woody species under controlled flooding conditions, the survival rate investigation of some woody plant species planted in the TGR WLFZ, and the physiological responses of some woody plant species during the recovery stage after winter floods. The results of woody species investigation showed that most woody plant species that existed as annual seedlings in the TGR WLFZ are not suitable candidates for the riparian protection forests. However, arbor species (e.g., Salix matsudana, Populus×canadensis, Morus alba, Pterocarya stenoptera, Taxodium ascendens, and Metasequoia glyptostroboides) and shrub species (e.g., Salix variegata, Distylium chinensis, Lycium chinense, Myricaria laxiflora, and Rosa multiflora) might be considered suitable candidates for the riparian protection forests in the TGR WLFZ by survival rate analyses under controlled winter flooding conditions, and survival rate investigations of woody plant species planted in the TGR WLFZ, respectively. Physiological analyses showed that P.×canadensis, M. alba, L. chinense, and S. variegata could develop specific self-repairing mechanisms to stimulate biomass accumulation and carbohydrate synthesis via the increases in chlorophyll pigments and photosynthesis during recovery after winter floods. Our results suggested these woody plant species could endure the winter flooding stress and recover well, and be used as candidate for the construction of riparian protection forests in the TGR WLFZ.

Utilizing forest tree genetic diversity for an adaptation of forest to climate change

NASA Astrophysics Data System (ADS)

Schueler, Silvio; Lackner, Magdalena; Chakraborty, Debojyoti

2017-04-01

Since climate conditions are considered to be major determinants of tree species' distribution ranges and drivers of local adaptation, anthropogenic climate change (CC) is expected to modify the distribution of tree species, tree species diversity and the forest ecosystems connected to these species. The expected speed of environmental change is significantly larger than the natural migration and adaptation capacity of trees and makes spontaneous adjustment of forest ecosystems improbable. Planting alternative tree species and utilizing the tree species' intrinsic adaptive capacity are considered to be the most promising adaptation strategy. Each year about 900 million seedlings of the major tree species are being planted in Central Europe. At present, the utilization of forest reproductive material is mainly restricted to nationally defined ecoregions (seed/provenance zones), but when seedlings planted today become adult, they might be maladapted, as the climate conditions within ecoregions changed significantly. In the cooperation project SUSTREE, we develop transnational delineation models for forest seed transfer and genetic conservation based on species distribution models and available intra-specific climate-response function. These models are being connected to national registers of forest reproductive material in order support nursery and forest managers by selecting the appropriate seedling material for future plantations. In the long-term, European and national policies as well as regional recommendations for provenances use need to adapted to consider the challenges of climate change.

The Influence of Land Subsidence, Quarrying, Drainage, Irrigation and Forest Fire on Groundwater Resources and Biodiversity Along the Southern Po Plain Coastal Zone (Italy)

NASA Astrophysics Data System (ADS)

Antonellini, M. A.; Mollema, P. N.

2014-12-01

The coastal zone of the southern Po plain is characterized by low lying land, which is reclaimed to permit settlements and agriculture. The history, tourism resorts and peculiar coastal environments make this territory attractive and valuable. Natural and fluid-extraction-induced land subsidence along with coastal erosion are major problems. Touristic development has strongly modified the landscape; coastal dunes have been in part removed to make room for hotels and quarrying has caused the formation of gravel pit lakes close to the shoreline. Protected natural areas include a belt of coastal dunes, wetlands, and the internal historical forests of San Vitale and Classe. The dunes have largely lost their original vegetation ecosystem, because years ago they have been colonized with pine trees to protect the adjacent farmland from sea spray. These pine forests are currently a fire hazard. Land reclamation drainage keeps the water table artificially low. Results of these anthropogenic disturbances on the hydrology include a decrease in infiltration rates, loss of freshwater surface bodies, encroachment of saltwater inland from the river estuaries, salinization of the aquifer, wetlands and soil with a loss in plant and aquatic species biodiversity. Feedback mechanisms are complex: as land subsidence continues, drainage increases at the same pace promoting sea-water intrusion. The salinity of the groundwater does not allow for plant species richness nor for the survival of large pine trees. Farmland irrigation and fires in the pine forests, on the other hand, allow for increased infiltration and freshening of the aquifer and at the same time promote plant species diversity. Our work shows that the characteristics of the southern Po coastal zone require integrated management of economic activities, natural areas, and resources. This approach is different from the ad hoc measures taken so far, because it requires long term planning and setting a priority of objectives.

Discrimination of plant root zone water status in greenhouse production based on phenotyping and machine learning techniques.

PubMed

Guo, Doudou; Juan, Jiaxiang; Chang, Liying; Zhang, Jingjin; Huang, Danfeng

2017-08-15

Plant-based sensing on water stress can provide sensitive and direct reference for precision irrigation system in greenhouse. However, plant information acquisition, interpretation, and systematical application remain insufficient. This study developed a discrimination method for plant root zone water status in greenhouse by integrating phenotyping and machine learning techniques. Pakchoi plants were used and treated by three root zone moisture levels, 40%, 60%, and 80% relative water content. Three classification models, Random Forest (RF), Neural Network (NN), and Support Vector Machine (SVM) were developed and validated in different scenarios with overall accuracy over 90% for all. SVM model had the highest value, but it required the longest training time. All models had accuracy over 85% in all scenarios, and more stable performance was observed in RF model. Simplified SVM model developed by the top five most contributing traits had the largest accuracy reduction as 29.5%, while simplified RF and NN model still maintained approximately 80%. For real case application, factors such as operation cost, precision requirement, and system reaction time should be synthetically considered in model selection. Our work shows it is promising to discriminate plant root zone water status by implementing phenotyping and machine learning techniques for precision irrigation management.

Declining plant nitrogen supply and carbon accumulation in ageing primary boreal forest ecosystems

NASA Astrophysics Data System (ADS)

Högberg, Mona N.; Yarwood, Stephanie A.; Trumbore, Susan; Högberg, Peter

2016-04-01

Boreal forest soils are commonly characterized by a low plant nitrogen (N) supply. A high tree below-ground allocation of carbon (C) to roots and soil microorganisms in response to the shortage of N may lead to high microbial immobilisation of N, thus aggravating the N limitation. We studied the N supply at a Swedish boreal forest ecosystem chronosequence created by new land rising out of the sea due to iso-static rebound. The youngest soils develop with meadows by the coast, followed by a zone of dinitrogen fixing alder trees, and primary boreal conifer forest on ground up to 560 years old. With increasing ecosystem age, the proportion of microbial C out of the total soil C pool from the youngest to the oldest coniferous ecosystem was constant (c. 1-1.5%), whereas immobilised N (microbial N out of total soil N) increased and approached the levels commonly observed in similar boreal coniferous forests (c. 6-7 %), whereas gross N mineralization declined. Simultaneously, plant foliar N % decreased and the natural abundance of N-15 in the soil increased. More specifically, the difference in N-15 between plant foliage and soil increased, which is related to greater retention of N-15 relative to N-14 by ectomycorrhizal fungi as N is taken up from the soil and some N is transferred to the plant host. In the conifer forest, where these changes were greatest, we found increased fungal biomass in the F- and H-horizons of the mor-layer, in which ectomycorrhizal fungi are known to dominate (the uppermost horizon with litter and moss is dominated by saprotrophic fungi). Hence, we propose that the decreasing N supply to the plants and the subsequent decline in plant production in ageing boreal forests is linked to high tree belowground C allocation to C limited ectomycorrhizal fungi (and other soil microorganisms), a strong sink for available soil N. Data on organic matter C-14 suggested that the largest input of recently fixed plant C occurred in the younger coniferous forest ecosystems, whereas the soil C accumulation rate declined as N supply to the plants declined.

Biological Invasion Influences the Outcome of Plant-Soil Feedback in the Invasive Plant Species from the Brazilian Semi-arid.

PubMed

de Souza, Tancredo Augusto Feitosa; de Andrade, Leonaldo Alves; Freitas, Helena; da Silva Sandim, Aline

2017-05-30

Plant-soil feedback is recognized as the mutual interaction between plants and soil microorganisms, but its role on the biological invasion of the Brazilian tropical seasonal dry forest by invasive plants still remains unclear. Here, we analyzed and compared the arbuscular mycorrhizal fungi (AMF) communities and soil characteristics from the root zone of invasive and native plants, and tested how these AMF communities affect the development of four invasive plant species (Cryptostegia madagascariensis, Parkinsonia aculeata, Prosopis juliflora, and Sesbania virgata). Our field sampling revealed that AMF diversity and frequency of the Order Diversisporales were positively correlated with the root zone of the native plants, whereas AMF dominance and frequency of the Order Glomerales were positively correlated with the root zone of invasive plants. We grew the invasive plants in soil inoculated with AMF species from the root zone of invasive (I changed ) and native (I unaltered ) plant species. We also performed a third treatment with sterilized soil inoculum (control). We examined the effects of these three AMF inoculums on plant dry biomass, root colonization, plant phosphorous concentration, and plant responsiveness to mycorrhizas. We found that I unaltered and I changed promoted the growth of all invasive plants and led to a higher plant dry biomass, mycorrhizal colonization, and P uptake than control, but I changed showed better results on these variables than I unaltered . For plant responsiveness to mycorrhizas and fungal inoculum effect on plant P concentration, we found positive feedback between changed-AMF community (I changed ) and three of the studied invasive plants: C. madagascariensis, P. aculeata, and S. virgata.

Visualizing Zonation Patterns

ERIC Educational Resources Information Center

Baumgartner, Erin; Zabin, Chela J.

2006-01-01

The study of "zonation", the distribution of plants and animals into distinct spatial areas, is a great way to introduce students to basic ecological concepts. Students can conduct methodical, quantifying surveys of zones in areas as diverse as mudflats, beaches, forests, wetlands, and fields. Students collect data from these areas with field…

Redox potential: An indicator of site productivity in forest management

NASA Astrophysics Data System (ADS)

Sajedi, Toktam; Prescott, Cindy; Lavkulich, Les

2010-05-01

Redox potential (Eh) is an integrated soil measurement that reflects several environmental conditions in the soil associated with aeration, moisture and carbon (organic matter) dynamics. Its measurement can be related to water table fluctuations, precipitation and landscape gradients, organic matter decomposition rates, nutrient dynamics, biological diversity and plant species distribution. Redox is an excellent indicator of soil biological processes, as it is largely a reflection of microbial activities which to a large extent govern carbon dynamics and nutrient cycling. Redox thus serves as an ecological indicator of site productivity at the ecosystem scale and may be used for management purposes as its magnitude can be altered by activities such as harvesting and drainage. A threshold value of 300 mv has been documented as the critical value below which anaerobic conditions in the soil develop. However, redox measurements and its impacts on ecosystem processes such as nutrient cycling and productivity, especially in forest ecosystems, have not received the attention that this "master" variable deserves, On northern Vancouver Island, Canada, regenerating stands of western redcedar-western hemlock (CH) sites exhibit symptoms of nutrient deficiencies and slow growth, but this phenomenon does not occur on adjacent western hemlock- amabalis fir (HA) sites. We tested the hypothesis that differences in nutrient supply and distribution of plant species was caused by differences in moisture regime and redox potential. Redox potential, pH, soil aeration depth (steel rods), organic matter thickness, bulk density, soil carbon store, plant species distribution and richness were measured at five old-growth and five 10-year-old cutover blocks. Results of investigations confirmed that CH forests were wetter, had redox values lower than the critical 300mv and a shallower aerated zone, compared with adjacent regenerating HA sites. Fifty percent of the CH plots had redox values less than +300 mv in the forest floor; whereas only 15 percent of the HA plots had such low values. Composition of the forest understory species was related to soil moisture/aeration. Soil aeration was the most important soil variable influencing plant species composition, explaining 25% of the plant community variability. Eh was always greater than +300 mv in the mineral soil of old growth HA forests but below +300 mv in HA clearcuts, suggesting paludification; however it was below or at this threshold in both CH forests and clearcuts. The reduction in measured redox without a noticeable change in the watertable in HA sites suggests that harvesting HA forests shifts the ecosystem towards more anaerobic conditions more similar to CH sites. In a complimentary study, the significance of redox was assessed in a cedar swamp cutover by exploring the relationships between soil redox potential and tree growth, and mineralization of C and soil C store along a gradient of moisture caused by drainage. Drainage improved aeration in the rooting zone, expressed as redox, and above- and below ground C storage; however C mineralization measured as CO2 evolution was not affected. Tree growth was positively correlated with redox potential. Our results indicate that drainage could be a useful silvicultural practice for improving the productivity of these ecosystems and that it may be possible to improve tree growth without stimulating loss of soil C. This requires that drainage improve aeration in the rooting zone while maintaining redox levels of less than +300 mV in the bulk soil, indicating that redox measurements should be incorporated into silviculture interventions to improve productivity of these forests.

When CO2 kills: effects of magmatic CO2 flux on belowground biota at Mammoth Mountain, CA

NASA Astrophysics Data System (ADS)

McFarland, J.; Waldrop, M. P.; Mangan, M.

2011-12-01

The biomass, composition, and activity of the soil microbial community is tightly linked to the composition of the aboveground plant community. Microorganisms in aerobic surface soils, both free-living and plant-associated are largely structured by the availability of growth limiting carbon (C) substrates derived from plant inputs. When C availability declines following a catastrophic event such as the death of large swaths of trees, the number and composition of microorganisms in soil would be expected to decline and/or shift to unique microorganisms that have better survival strategies under starvation conditions. High concentrations of volcanic cold CO2 emanating from Mammoth Mountain near Horseshoe Lake on the southwestern edge of Long Valley Caldera, CA has resulted in a large kill zone of tree species, and associated soil microbial species. In July 2010, we assessed belowground microbial community structure in response to disturbance of the plant community along a gradient of soil CO2 concentrations grading from <0.6% (ambient forest) to >80% (no plant life). We employed a microbial community fingerprinting technique (automated ribosomal intergenic spacer analysis) to determine changes in overall community composition for three broad functional groups: fungi, bacteria, and archaea. To evaluate changes in ectomycorrhizal fungal associates along the CO2 gradient, we harvested root tips from lodgepole pine seedlings collected in unaffected forest as well as at the leading edge of colonization into the kill zone. We also measured soil C fractions (dissolved organic C, microbial biomass C, and non-extractable C) at 10 and 30 cm depth, as well as NH4+. Not surprisingly, our results indicate a precipitous decline in soil C, and microbial C with increasing soil CO2; phospholipid fatty acid analysis in conjunction with community fingerprinting indicate both a loss of fungal diversity as well as a dramatic decrease in biomass as one proceeds further into the kill zone. This observation was concomitant with a relative increase in bacterial and archaeal contributions to microbial community structure. Root tip analyses among lodgepole seedlings recolonizing the kill zone area demonstrated a significant reduction in the overall diversity of fungal symbionts, as well as a distinct shift in fungal assemblages. In particular, within elevated CO2 areas, we observed a high infection level for the ascomycetous fungi, Wilcoxina spp., which appear particularly well-adapted for colonization in disturbed environments. It remains unclear whether dominance by ascomycetes among seedlings in elevated CO2 areas represents a coordinated shift orchestrated by the plant in response to physiological stress, or whether these fungi are simply more opportunistic than their basdiomycetous counterparts. Our results demonstrate the impact of large-scale disturbances on plant-microbial interactions and belowground processes in previously forested ecosystems.

Monitoring shifts in plant diversity in response to climate change: A method for landscapes

USGS Publications Warehouse

Stohlgren, T.J.; Owen, A.J.; Lee, M.

2000-01-01

Improved sampling designs are needed to detect, monitor, and predict plant migrations and plant diversity changes caused by climate change and other human activities. We propose a methodology based on multi-scale vegetation plots established across forest ecotones which provide baseline data on patterns of plant diversity, invasions of exotic plant species, and plant migrations at landscape scales in Rocky Mountain National Park, Colorado, USA. We established forty two 1000-m2 plots in relatively homogeneous forest types and the ecotones between them on 14 vegetation transects. We found that 64% of the variance in understory species distributions at landscape scales were described generally by gradients of elevation and under-canopy solar radiation. Superimposed on broad-scale climatic gradients are small-scale gradients characterized by patches of light, pockets of fertile soil, and zones of high soil moisture. Eighteen of the 42 plots contained at least one exotic species; monitoring exotic plant invasions provides a means to assess changes in native plant diversity and plant migrations. Plant species showed weak affinities to overstory vegetation types, with 43% of the plant species found in three or more vegetation types. Replicate transects along several environmental gradients may provide the means to monitor plant diversity and species migrations at landscape scales because: (1) ecotones may play crucial roles in expanding the geophysiological ranges of many plant species; (2) low affinities of understory species to overstory forest types may predispose vegetation types to be resilient to rapid environmental change; and (3) ecotones may help buffer plant species from extirpation and extinction.

Changes in Nitrogen Cycling during Tropical Forest Secondary Succession on Abandoned Pastures

NASA Astrophysics Data System (ADS)

Mirza, S.; Rivera, R. J.; Marin-Spiotta, E.

2017-12-01

Nitrogen (N) plays two important roles in Earth's climate. As a plant nutrient, the availability of N affects plant growth and the uptake of carbon (C) from the atmosphere into plant biomass. The accumulation of C in long-lived biomass and in soils contributes to reducing the amount of CO2 in the atmosphere. Secondly, excess N can lead to the production of N2O, which is a more potent greenhouse than CO2. Humans have altered the cycling of N in terrestrial ecosystems, affecting their potential to sequester C and help mitigate climate change. Land-use change, specifically deforestation and reforestation, can affect N availability for plant growth and N2O production. Long-term agricultural use can deplete nitrogen sources, even in tropical soils where N is not expected to limit productivity. Secondary succession and reforestation can allow for the recovery of N stocks and fluxes, with implications for C cycling and N2O emissions. N limitation in pastures and early successional forests increases the demand for N-fixing tree species, but previous research has shown that there is a greater abundance of N-fixing species in older forests (Batterman et. al 2013). Successional trends in N mineralization and denitrification vary across studies, with some showing greater rates in agricultural soils or in mature forest soils, compared to early successional sites. Here we examine changes in N-fixing species, above and belowground N pools, and N cycling rates in secondary forests on former pastures on Oxisols in the wet tropical forest life zone of Puerto Rico. The availability of a long-term well-replicated chronosequence provides us with the opportunity to study decadal trends in N processes during forest recovery after agricultural abandonment.

Ecology and behaviour of the Alder Flycatcher Empidonax alnorum, Tyrannidae in winter

USGS Publications Warehouse

Foster, M.; Adams, N.J.; Slotow, R.H.

1999-01-01

The Alder Flycatcher Empidonax alnorum (Tyrannidae) winters from Colombia and Venezuela, south to northern Argentina. We studied the species in Manu National Park, Madre de Dios, Peru. In this area the species occupies riparian zones along lowland meander rivers as well as adjacent transition zone forest in the floodplain. These habitats have a number of age-related longitudinal zones (parallel to the river margin) that are short term (I-2 year) transitory stages in the succession to floodplain forest. The fast growing plant species that make up these habitats are suitable for commercial harvest for paper pulp. We examined habitat use of the species in an attempt to identify the effects of such harvest and resulting habitat loss on these birds. The Alder Flycatcher favours two longitudinal zones where it establishes territories. The territories may be long-term or transitory, and are often occupied and defended by two individuals, generally of different age. One bird tends to be more active in territory defence than the other. Defence involves patrolling, vocal duels, and chases. Birds sally for insects but also eat large quantities of fruit.

Ecology and behaviour of the Alder Flycatcher Empidonax alnorum, Tyrannidae in winter

USGS Publications Warehouse

Foster, M.; Adams, N.J.; Slotow, R.H.

1998-01-01

The Alder Flycatcher Empidonax alnorum (Tyrannidae) winters from Colombia and Venezuela, south to northern Argentina. We studied the species in Manu National Park, Madre de Dios, Peru. In this area the species occupies riparian zones along lowland meander rivers as well as adjacent transition zone forest in the floodplain. These habitats have a number of age-related longitudinal zones (parallel to the river margin) that are short term (I-2 year) transitory stages in the succession to floodplain forest. The fast growing plant species that make up these habitats are suitable for commercial harvest for paper pulp. We examined habitat use of the species in an attempt to identify the effects of such harvest and resulting habitat loss on these birds. The Alder Flycatcher favours two longitudinal zones where it establishes territories. The territories may be long-term or transitory, and are often occupied and defended by two individuals, generally of different age. One bird tends to be more active in territory defence than the other. Defence involves patrolling, vocal duels, and chases. Birds sally for insects but also eat large quantities of fruit.

Climate-Smart Seedlot Selection Tool: Reforestation and Restoration for the 21st Century

NASA Astrophysics Data System (ADS)

Stevenson-Molnar, N.; Howe, G.; St Clair, B.; Bachelet, D. M.; Ward, B. C.

2017-12-01

Local populations of trees are generally adapted to their local climates. Historically, this has meant that local seed zones based on geography and elevation have been used to guide restoration and reforestation. In the face of climate change, seeds from local sources will likely be subjected to climates significantly different from those to which they are currently adapted. The Seedlot Selection Tool (SST) offers a new approach for matching seed sources with planting sites based on future climate scenarios. The SST is a mapping program designed for forest managers and researchers. Users can use the tool to to find seedlots for a given planting site, or to find potential planting sites for a given seedlot. Users select a location (seedlot or planting site), climate scenarios (a climate to which seeds are adapted, and a current or future climate scenario), climate variables, and transfer limits (the maximum climatic distance that is considered a suitable match). Transfer limits are provided by the user, or derived from the range of values within a geographically defined seed zone. The tool calculates scores across the landscape based on an area's similarity, in a multivariate climate space, to the input. Users can explore results on an interactive map, and export PDF and PowerPoint reports, including a map of the results along with the inputs used. Planned future improvements include support for non-forest use cases and ability to download results as GeoTIFF data. The Seedlot Selection Tool and its source code are available online at https://seedlotselectiontool.org. It is co-developed by the United States Forest Service, Oregon State University, and the Conservation Biology Institute.

Bistability of mangrove forests and competition with freshwater plants

USGS Publications Warehouse

Jiang, Jiang; Fuller, Douglas O; Teh, Su Yean; Zhai, Lu; Koh, Hock Lye; DeAngelis, Donald L.; Sternberg, L.D.S.L.

2015-01-01

Halophytic communities such as mangrove forests and buttonwood hammocks tend to border freshwater plant communities as sharp ecotones. Most studies attribute this purely to underlying physical templates, such as groundwater salinity gradients caused by tidal flux and topography. However, a few recent studies hypothesize that self-reinforcing feedback between vegetation and vadose zone salinity are also involved and create a bistable situation in which either halophytic dominated habitat or freshwater plant communities may dominate as alternative stable states. Here, we revisit the bistability hypothesis and demonstrate the mechanisms that result in bistability. We demonstrate with remote sensing imagery the sharp boundaries between freshwater hardwood hammock communities in southern Florida and halophytic communities such as buttonwood hammocks and mangroves. We further document from the literature how transpiration of mangroves and freshwater plants respond differently to vadose zone salinity, thus altering the salinity through feedback. Using mathematical models, we show how the self-reinforcing feedback, together with physical template, controls the ecotones between halophytic and freshwater communities. Regions of bistability along environmental gradients of salinity have the potential for large-scale vegetation shifts following pulse disturbances such as hurricane tidal surges in Florida, or tsunamis in other regions. The size of the region of bistability can be large for low-lying coastal habitat due to the saline water table, which extends inland due to salinity intrusion. We suggest coupling ecological and hydrologic processes as a framework for future studies.

Life forms, leaf size spectra, regeneration capacity and diversity of plant species grown in the Thandiani forests, district Abbottabad, Khyber Pakhtunkhwa, Pakistan.

PubMed

Khan, Waqas; Khan, Shujaul Mulk; Ahmad, Habib; Alqarawi, Abdulaziz A; Shah, Ghulam Mujtaba; Hussain, Manzoor; Abd Allah, E F

2018-01-01

The life form and leaf size spectra of plant species of the Thandiani forests, district Abbottabad, were studied during the summer of 2013. These forests host 252 plant species of 97 families. Biological spectra showed that Hemicryptophytes (80 spp., 31.74%) were dominant followed by Megaphanerophytes (51 spp., 20.24%), Therophytes (49 spp., 19.44%) and Nanophanerophytes (45 spp., 17.86). Hemicryptophytes are the indicators of cold temperate vegetation. At the lower elevations, Megaphanerophytes and Nanophanerophytes were dominant which confirm trees as dominant habit form due to high soil depth, moisture and temperature factors. Data on Leaf spectra in the area showed that Microphyllous (88 spp., 34.92%) species were dominant followed by Leptophyllous (74 spp., 29.36%) and Nanophyllous (60 spp., 23.80%). The Microphyllous plants again are the indicator of cold temperate zone as the area is situated at an elevation of 1191-2626 m. Similarly, Nanophylls were dominant at lower elevations. Data on family importance values and diversity among various communities were also recorded. Life form and Leaf spectra studies could be used to understand the micro climatic variation of the region.

76 FR 61599 - Endangered and Threatened Wildlife and Plants; Revised Critical Habitat for the Marbled Murrelet

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-05

..., which suggests that forest type influences murrelet occurrence, rather than absolute distance from the... zone, and not the distance from the coast. This is probably due to the maritime climate that provides... hotter, drier climate. This rapid transition to less favorable conditions for murrelets may explain why...

[Characteristics of soil organic carbon and enzyme activities in soil aggregates under different vegetation zones on the Loess Plateau].

PubMed

Li, Xin; Ma, Rui-ping; An, Shao-shan; Zeng, Quan-chao; Li, Ya-yun

2015-08-01

In order to explore the distribution characteristics of organic carbon of different forms and the active enzymes in soil aggregates with different particle sizes, soil samples were chosen from forest zone, forest-grass zone and grass zone in the Yanhe watershed of Loess Plateau to study the content of organic carbon, easily oxidized carbon, and humus carbon, and the activities of cellulase, β-D-glucosidase, sucrose, urease and peroxidase, as well as the relations between the soil aggregates carbon and its components with the active soil enzymes were also analyzed. It was showed that the content of organic carbon and its components were in order of forest zone > grass zone > forest-grass zone, and the contents of three forms of organic carbon were the highest in the diameter group of 0.25-2 mm. The content of organic carbon and its components, as well as the activities of soil enzymes were higher in the soil layer of 0-10 cm than those in the 10-20 cm soil layer of different vegetation zones. The activities of cellulase, β-D-glucosidase, sucrose and urease were in order of forest zone > grass zone > forest-grass zone. The peroxidase activity was in order of forest zone > forest-grass zone > grass zone. The activities of various soil enzymes increased with the decreasing soil particle diameter in the three vegetation zones. The activities of cellulose, peroxidase, sucrose and urease had significant positive correlations with the contents of various forms of organic carbon in the soil aggregates.

Archaeological and Historical Reconnaissance Survey of the Ugum River Valley, Guam, Mariana Islands,

DTIC Science & Technology

1978-08-01

important food plant in Micro- neisa; and betel nut (Areca catechu), chewed for its stimulant effect . Although feral yams (Dioscorea sp.) were not found...determining action required to mitigate the adverse effects of proposed dam construction and sub- sequent flooding of the upper Ugum River drainage. The dam...A:33). Plant identifications were made with reference to Stone (1970). Zone 1 is a mixed, broad- leafed , tropical forest (Fosberg’s Unit 2;. Tracey et

Examining the Relationship Between Edaphic Variables and the Rooting System of Abies concolor in the southern Sierra Nevada

NASA Astrophysics Data System (ADS)

Wilson, A.; Jackson, R. B.; Tumber-Davila, S. J.

2017-12-01

An increase in the frequency and severity of droughts has been associated with the changing climate. These events have the potential to alter the composition and biogeography of forests, as well as increase tree mortality related to climate-induced stress. Already, an increase in tree mortality has been observed throughout the US. The recent drought in California led to millions of tree mortalities in the southern Sierra Nevada alone. In order to assess the potential impacts of these events on forest systems, it is imperative to understand what factors contribute to tree mortality. As plants become water-stressed, they may invest carbon more heavily belowground to reach a bigger pool of water, but their ability to adapt may be limited by the characteristics of the soil. In the Southern Sierra Critical Zone Observatory, a high tree mortality zone, we have selected both dead and living trees to examine the factors that contribute to root zone variability and belowground biomass investment by individual plants. A series of 15 cores surrounding the tree were taken to collect root and soil samples. These were then used to compare belowground rooting distributions with soil characteristics (texture, water holding capacity, pH, electric conductivity). Abies concolor is heavily affected by drought-induced mortality, therefore the rooting systems of dead Abies concolor trees were examined to determine the relationship between their rooting systems and environmental conditions. Examining the relationship between soil characteristics and rooting systems of trees may shed light on the plasticity of rooting systems and how trees adapt based on the characteristics of its environment. A better understanding of the factors that contribute to tree mortality can improve our ability to predict how forest systems may be impacted by climate-induced stress. Key words: Root systems, soil characteristics, drought, adaptation, terrestrial carbon, forest ecology

Human and climate impact on ¹⁵N natural abundance of plants and soils in high-mountain ecosystems: a short review and two examples from the Eastern Pamirs and Mt. Kilimanjaro.

PubMed

Zech, Michael; Bimüller, Carolin; Hemp, Andreas; Samimi, Cyrus; Broesike, Christina; Hörold, Claudia; Zech, Wolfgang

2011-09-01

Population pressure increasingly endangers high-mountain ecosystems such as the pastures in the Eastern Pamirs and the mountain forests on Mt. Kilimanjaro. At the same time, these ecosystems constitute the economic basis for millions of people living there. In our study, we, therefore, aimed at characterising the land-use effects on soil degradation and N-cycling by determining the natural abundance of (15)N. A short review displays that δ(15)N of plant-soil systems may often serve as an integrated indicator of N-cycles with more positive δ(15)N values pointing towards N-losses. Results for the high-mountain pastures in the Eastern Pamirs show that intensively grazed pastures are significantly enriched in (15)N compared to the less-exploited pastures by 3.5 ‰, on average. This can be attributed to soil organic matter degradation, volatile nitrogen losses, nitrogen leaching and a general opening of the N-cycle. Similarly, the intensively degraded savanna soils, the cultivated soils and the soils under disturbed forests on the foothill of Mt. Kilimanjaro reveal very positive δ(15)N values around 6.5 ‰. In contrast, the undisturbed forest soils in the montane zone are more depleted in (15)N, indicating that here the N-cycle is relatively closed. However, significantly higher δ(15)N values characterise the upper montane forest zone at the transition to the subalpine zone. We suggest that this reflects N-losses by the recently monitored and climate change and antropogenically induced increasing fire frequency pushing the upper montane rainforest boundary rapidly downhill. Overall, we conclude that the analysis of the (15)N natural abundance in high-mountain ecosystems is a purposeful tool for detecting land-use- or climate change-induced soil degradation and N-cycle opening.

Nitrogen limitation of growth and nutrient dynamics in a disturbed mangrove forest, Indian River Lagoon, Florida

USGS Publications Warehouse

Feller, Ilka C.; Whigham, D.F.; McKee, K.L.; Lovelock, C.E.

2003-01-01

The objectives of this study were to determine effects of nutrient enrichment on plant growth, nutrient dynamics, and photosynthesis in a disturbed mangrove forest in an abandoned mosquito impoundment in Florida. Impounding altered the hydrology and soil chemistry of the site. In 1997, we established a factorial experiment along a tree-height gradient with three zones, i.e., fringe, transition, dwarf, and three fertilizer treatment levels, i.e., nitrogen (N), phosphorus (P), control, in Mosquito Impoundment 23 on the eastern side of Indian River. Transects traversed the forest perpendicular to the shoreline, from a Rhizophora mangle-dominated fringe through an Avicennia germinans stand of intermediate height, and into a scrub or dwarf stand of A. germinans in the hinterland. Growth rates increased significantly in response to N fertilization. Our growth data indicated that this site is N-limited along the tree-height gradient. After 2 years of N addition, dwarf trees resembled vigorously growing saplings. Addition of N also affected internal dynamics of N and P and caused increases in rates of photosynthesis. These findings contrast with results for a R. mangle-dominated forest in Belize where the fringe is N-limited, but the dwarf zone is P-limited and the transition zone is co-limited by N and P. This study demonstrated that patterns of nutrient limitation in mangrove ecosystems are complex, that not all processes respond similarly to the same nutrient, and that similar habitats are not limited by the same nutrient when different mangrove forests are compared.

Heavy metal pollution and forest health in the Ukrainian Carpathians.

PubMed

Shparyk, Y S; Parpan, V I

2004-07-01

The Ukrainian Carpathians are characterized by high air pollution caused by emissions from numerous industries. We have been monitoring the state of forests in this region since 1989. The highest levels of tree defoliation (>30%) are found close to industrial emission sources and in the upper mountain forests of the Ivano-Frankivsk and Chernivtsi regions. This is caused by a combination of strong anthropogenic influences (pollution, illegal uses, recreation) as well as poor site and climatic conditions. In the Ivano-Frankivsk region, Cd and Mo accumulate in forest soils; Cr, Mo and Zn soil concentrations are higher than their limit levels; and Pb concentrations exceed toxic levels close to industrial areas (10% of the region territory). Local background levels of heavy metals are greatly exceeded in snow close to industrial regions. Analysis of correlation matrices shows that the chemical elements Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn occur at pollution levels in natural ecosystems in the Ukrainian Carpathians. Maximum concentrations of toxic elements occur in the oak forest zone; the most industrially developed area of the region. Toxic heavy metals in the Ukrainian Carpathians forests enter with precipitation and dustfall, then become fixed in soil and accumulate in leaves, needles of vascular plants and mosses. Concentrations of these metals decrease with altitude: highest in the oak forests, less in beech, and lowest in the spruce forest zones. However, some chemical elements have the highest concentrations in spruce forests; V in needles, As in snow, and Ba and Al in soils.

The Evolution of Root Zone Storage Capacity after Land Use Change

NASA Astrophysics Data System (ADS)

Nijzink, Remko C.; Hutton, Christopher; Pechlivanidis, Ilias; Capell, René; Arheimer, Berit; Wagener, Thorsten; Savenije, Hubert H. G.; Hrachowitz, Markus

2016-04-01

Root zone storage capacity forms a crucial parameter in ecosystem functioning as it is the key parameter that determines the partitioning between runoff and transpiration. There is increasing evidence from several case studies for specific plants that vegetation adapts to the critical situation of droughts. For example, trees will, on the long term, try to improve their internal hydraulic conductivity after droughts, for example by allocating more biomass for roots. In spite of this understanding, the water storage capacity in the root zone is often treated as constant in hydrological models. In this study, it was hypothesized that root zone storage capacities are altered by deforestation and the regrowth of the ecosystem. Three deforested sub catchments as well as not affected, nearby control catchments of the experimental forests of HJ Andrews and Hubbard Brook were selected for this purpose. Root zone storage capacities were on the one hand estimated by a climate-based approach similar to Gao et al. (2014), making use of simple water balance considerations to determine the evaporative demand of the system. In this way, the maximum deficit between evaporative demand and precipitation allows a robust estimation of the root zone storage capacity. On the other hand, three conceptual hydrological models (FLEX, HYPE, HYMOD) were calibrated in a moving window approach for all catchments. The obtained model parameter values representing the root zone storage capacities of the individual catchments for each moving window period were then compared to the estimates derived from climate data for the same periods. Model- and climate-derived estimates of root zone storage capacities both showed a similar evolution. In the deforested catchments, considerable reductions of the root zone storage capacities, compared to the pre-treatment situation and control catchments, were observed. In addition, the years after forest clearing were characterized by a gradual recovery of the root zone storage capacities, converging to new equilibrium conditions and linked to forest regrowth. Further trend analysis suggested a relatively quick hydrological recovery between 5 and 15 years in the study catchments. The results lend evidence to the role of both, climate and vegetation dynamics for the development of root zone systems and their controlling influence on hydrological response dynamics.

Width of forest streamside zones and breeding bird abundance in eastern Texas

Treesearch

Richard N. Conner; James G. Dickson; J. Howard Williamson; Brent Ortego

2004-01-01

We evaluated breeding bird communities in forested streamside zones in eastern Texas to determine threshold widths of riparian forest that were associated with the addition of mature-forest-breeding birds and loss of shrub-breeding birds. We observed an association of shrub-breeding birds with narrow streamside zones and an increasing number of mature forest species...

Suggestions for Forest Conservation Policy under Climate Change

NASA Astrophysics Data System (ADS)

Choe, H.; Thorne, J. H.; Lee, D. K.; Seo, C.

2015-12-01

Climate change and the destruction of natural habitats by land-use change are two main factors in decreasing terrestrial biodiversity. Studying land-use and climate change and their impact under different scenarios can help suggest policy directions for future events. This study explores the spatial results of different land use and climate models on the extent of species rich areas in South Korea. We built land use models of forest conversion and created four 2050 scenarios: (1) a loss trend following current levels, resulting in 15.5% lost; (2) similar loss, but with forest conservation in areas with suitable future climates; (3) a reduction of forest loss by 50%; and (4) a combination of preservation of forest climate refugia and overall reduction of loss by 50%. Forest climate refugia were identified through the use of species distribution models run on 1,031 forest plant species to project current and 2050 distributions. We calculated change in species richness under four climate projections, permitting an assessment of forest refugia zones. We then crossed the four land use models with the climate-driven change in species richness. Forest areas predominantly convert to agricultural areas, while climate-suitable extents for forest plants decline and move northward, especially to higher elevations. Scenario 2, that has the higher level of deforestation but protects future species rich areas, conserves nearly as much future biodiversity as scenario 3, which reduced deforestation rates by 50%. This points to the importance of including biogeographic climate dynamics in forest policy. Scenario 4 was the most effective at conserving forest biodiversity. We suggest conserving forest areas with suitable climates for biodiversity conservation and the establishment of monoculture plantations targeted to areas where species richness will decline based on our results.

Root strength changes after logging in southeast Alaska

Treesearch

R. R. Ziemer; D. N. Swanston

1977-01-01

Abstract - A crucial factor in the stability of steep forested slopes is the role of plant roots in maintaining the shear strength of soil mantles. Roots add strength to the soil by vertically anchoring through the soil mass into failures in the bedrock and by laterally tying the slope together across zones of weakness or instability. Once the covering vegetation is...

Plant composition in oak savanna and woodland restoration at Prairie Fork Conservation Area in Missouri

Treesearch

Nadia E. Navarrete-Tindall; J.W. Van Sambeek; Jamie Coe; Warren Taylor

2007-01-01

The wooded areas of the Prairie Fork Conservation Area in central Missouri are typical of the oak/hickory forest/prairie transition zone that will require active management to restore pre-settlement, grass dominated savannas and open woodlands to improve habitat for wildlife. We initiated a management program to restore savannas and woodlands by reducing the midstory (...

Revising the Seed Zones for Southern Pines

Treesearch

Ronald C. Schmidtling

1999-01-01

Early foresters had a sense that using local seed sources was the best for afforestation, although this was often based more on intuition than experience. Non-local planting stock has often been used in-the past. In the reforestation carried out by the Civilian Conservation Corps in the 1930's, for instance, an effort was made to use native seed sources, but...

Interspecific variation of the bacterial community structure in the phyllosphere of the three major plant components of mangrove forests

PubMed Central

Dias, Armando Cavalcante Franco; Taketani, Rodrigo Gouveia; Andreote, Fernando Dini; Luvizotto, Danice Mazzer; da Silva, João Luis; Nascimento, Rosely dos Santos; de Melo, Itamar Soares

2012-01-01

Mangrove forests encompass a group of trees species that inhabit the intertidal zones, where soil is characterized by the high salinity and low availability of oxygen. The phyllosphere of these trees represent the habitat provided on the aboveground parts of plants, supporting in a global scale, a large and complex microbial community. The structure of phyllosphere communities reflects immigration, survival and growth of microbial colonizers, which is influenced by numerous environmental factors in addition to leaf physical and chemical properties. Here, a combination of culture-base methods with PCR-DGGE was applied to test whether local or plant specific factors shape the bacterial community of the phyllosphere from three plant species (Avicenia shaueriana, Laguncularia racemosa and Rhizophora mangle), found in two mangroves. The number of bacteria in the phyllosphere of these plants varied between 3.62 x 104 in A. schaeriana and 6.26 x 103 in R. mangle. The results obtained by PCR-DGGE and isolation approaches were congruent and demonstrated that each plant species harbor specific bacterial communities in their leaves surfaces. Moreover, the ordination of environmental factors (mangrove and plant species), by redundancy analysis (RDA), also indicated that the selection exerted by plant species is higher than mangrove location on bacterial communities at phyllosphere. PMID:24031877

Interspecific variation of the bacterial community structure in the phyllosphere of the three major plant components of mangrove forests.

PubMed

Dias, Armando Cavalcante Franco; Taketani, Rodrigo Gouveia; Andreote, Fernando Dini; Luvizotto, Danice Mazzer; da Silva, João Luis; Nascimento, Rosely Dos Santos; de Melo, Itamar Soares

2012-04-01

Mangrove forests encompass a group of trees species that inhabit the intertidal zones, where soil is characterized by the high salinity and low availability of oxygen. The phyllosphere of these trees represent the habitat provided on the aboveground parts of plants, supporting in a global scale, a large and complex microbial community. The structure of phyllosphere communities reflects immigration, survival and growth of microbial colonizers, which is influenced by numerous environmental factors in addition to leaf physical and chemical properties. Here, a combination of culture-base methods with PCR-DGGE was applied to test whether local or plant specific factors shape the bacterial community of the phyllosphere from three plant species (Avicenia shaueriana, Laguncularia racemosa and Rhizophora mangle), found in two mangroves. The number of bacteria in the phyllosphere of these plants varied between 3.62 x 10(4) in A. schaeriana and 6.26 x 10(3) in R. mangle. The results obtained by PCR-DGGE and isolation approaches were congruent and demonstrated that each plant species harbor specific bacterial communities in their leaves surfaces. Moreover, the ordination of environmental factors (mangrove and plant species), by redundancy analysis (RDA), also indicated that the selection exerted by plant species is higher than mangrove location on bacterial communities at phyllosphere.

Legacies of flood reduction on a dryland river

USGS Publications Warehouse

Stromberg, J.C.; Shafroth, P.B.; Hazelton, A.F.

2012-01-01

The Bill Williams (Arizona) is a regulated dryland river that is being managed, in part, for biodiversity via flow management. To inform management, we contrasted riparian plant communities between the Bill Williams and an upstream free-flowing tributary (Santa Maria). Goals of a first study (1996-1997) were to identify environmental controls on herbaceous species richness and compare richness among forest types. Analyses revealed that herbaceous species richness was negatively related to woody stem density, basal area and litter cover and positively related to light levels. Introduced Tamarix spp. was more frequent at the Bill Williams, but all three main forest types (Tamarix, Salix/Populus, Prosopis) had low understory richness, as well as high stem density and low light, on the Bill Williams as compared to the Santa Maria. The few edaphic differences between rivers (higher salinity at Bill Williams) had only weak connections with richness. A second study (2006-2007) focused on floristic richness at larger spatial scales. It revealed that during spring, and for the study cumulatively (spring and fall samplings combined), the riparian zone of the unregulated river had considerably more plant species. Annuals (vs. herbaceous perennials and woody species) showed the largest between-river difference. Relative richness of exotic (vs. native) species did not differ. We conclude that: (1) The legacy of reduced scouring frequency and extent at the Bill Williams has reduced the open space available for colonization by annuals; and (2) Change in forest biomass structure, more so than change in forest composition, is the major driver of changes in plant species richness along this flow-altered river. Our study informs dryland river management options by revealing trade-offs that exist between forest biomass structure and plant species richness. ?? 2010 John Wiley & Sons, Ltd.

Clustering Timber Harvests and the Effects of Dynamic Forest Management Policy on Forest Fragmentation

Treesearch

Eric J. Gustafson

1998-01-01

To integrate multiple uses (mature forest and commodity production) better on forested lands, timber management strategies that cluster harvests have been proposed. One such approach clusters harvest activity in space and time, and rotates timber production zones across the landscape with a long temporal period (dynamic zoning). Dynamic zoning has...

Vertical distribution of radiocesium in soils of the area affected by the Fukushima Dai-ichi nuclear power plant accident

NASA Astrophysics Data System (ADS)

Konoplev, A. V.; Golosov, V. N.; Yoschenko, V. I.; Nanba, K.; Onda, Y.; Takase, T.; Wakiyama, Y.

2016-05-01

Presented are results of the study of radiocesium vertical distribution in the soils of the irrigation pond catchments in the near field 0.25 to 8 km from the Fukushima Dai-ichi NPP, on sections of the Niida River floodplain, and in a forest ecosystem typical of the territory contaminated after the accident. It is shown that the vertical migration of radiocesium in undisturbed forest and grassland soils in the zone affected by the Fukushima accident is faster than it was in the soils of the 30-km zone of the Chernobyl NPP for a similar time interval after the accident. The effective dispersion coefficients in the Fukushima soils are several times higher than those for the Chernobyl soils. This may be associated with higher annual precipitation (by about 2.5 times) in Fukushima as compared to the Chernobyl zone. In the forest soils the radiocesium dispersion is faster as compared to grassland soils, both in the Fukushima and Chernobyl zones. The study and analysis of the vertical distribution of the Fukushima origin radiocesium in the Niida gawa floodplain soils has made it possible to identify areas of contaminated sediment accumulation on the floodplain. The average accumulation rate for sediments at the study locations on the Niida gawa floodplain varied from 0.3 to 3.3 cm/year. Taking into account the sediments accumulation leading to an increase in the radiocesium inventory in alluvial soils is key for predicting redistribution of radioactive contamination after the Fukushima accident on the river catchments, as well as for decision-making on contaminated territories remediation and clean-up. Clean-up of alluvial soils does not seem to be worthwhile because of the following accumulation of contaminated sediments originating from more contaminated areas, including the exclusion zone.

CO2 flux studies of different hemiboreal forest ecosystems

NASA Astrophysics Data System (ADS)

Krasnova, Alisa; Krasnov, Dmitrii; Noe, Steffen M.; Uri, Veiko; Mander, Ülo; Niinemets, Ülo; Soosaar, Kaido

2017-04-01

Hemiboreal zone is a transition between boreal and temperate zones characterized by the combination of climatic and edaphic conditions inherent in both zones. Hemiboreal forests are typically presented by mixed forests types with different ratios of deciduous and conifer tree species. Dominating tree species composition affects the functioning of forest ecosystem and its influence on biogeochemical cycles. We present the result of ecosystem scale CO2 eddy-covariance fluxes research conducted in 4 ecosystems (3 forests sites and 1 clear-cut area) of hemiboreal zone in Estonia. All 4 sites were developing under similar climatic conditions, but different forest management practices resulted in different composition of dominating tree species: pine forest with spruce trees as a second layer (Soontaga site); spruce/birch forest with single alder trees (Liispõllu site); forest presented by sectors of pine, spruce, birch and clearcut areas (SMEAR Estonia site); 5-years old clearcut area (Kõnnu site).

Plant-plant interactions in a subtropical mangrove-to-marsh transition zone: effects of environmental drivers

USGS Publications Warehouse

Howard, Rebecca J.; Krauss, Ken W.; Cormier, Nicole; Day, Richard H.; Biagas, Janelda M.; Allain, Larry K.

2015-01-01

Questions Does the presence of herbaceous vegetation affect the establishment success of mangrove tree species in the transition zone between subtropical coastal mangrove forests and marshes? How do plant–plant interactions in this transition zone respond to variation in two primary coastal environmental drivers? Location Subtropical coastal region of the southern United States. Methods We conducted a greenhouse study to better understand how abiotic factors affect plant species interactions in the mangrove-to-marsh transition zone, or ecotone. We manipulated salinity (fresh, brackish or salt water) and hydrologic conditions (continuously saturated or 20-cm tidal range) to simulate ecotonal environments. Propagules of the mangroves Avicennia germinans and Laguncularia racemosa were introduced to mesocosms containing an established marsh community. Both mangrove species were also introduced to containers lacking other vegetation. We monitored mangrove establishment success and survival over 22 mo. Mangrove growth was measured as stem height and above-ground biomass. Stem height, stem density and above-ground biomass of the dominant marsh species were documented. Results Establishment success of A. germinans was reduced under saturated saltwater conditions, but establishment of L. racemosa was not affected by experimental treatments. There was complete mortality of A. germinans in mesocosms under freshwater conditions, and very low survival of L. racemosa. In contrast, survival of both species in monoculture under freshwater conditions exceeded 62%. The marsh species Distichlis spicata and Eleocharis cellulosa suppressed growth of both mangroves throughout the experiment, whereas the mangroves did not affect herbaceous species growth. The magnitude of growth suppression by marsh species varied with environmental conditions; suppression was often higher in saturated compared to tidal conditions, and higher in fresh and salt water compared to brackish water. Conclusions Our results indicate that herbaceous marsh species can suppress mangrove early seedling growth. Depending on species composition and density, marsh plants can slow mangrove landward migration under predicted climate change scenarios as salinity in freshwater and oligohaline wetlands increases with rising sea levels. Change in the relative coverage of mangrove forests and marshes will depend on both the ability of marsh species to migrate further inland as mangroves advance, and the ability of shoreline mangroves to adjust to rising sea level through accretionary processes.

Evaluation of native plant seeds and seeding in the east-side central Cascades ponderosa pine zone

Treesearch

Nan C. Vance

2010-01-01

In dry, open coniferous forests of the montane West, stand-replacing wildfires and land use activities alter the composition and abundance of native grasses and forbs by degrading the habitat and accelerating the invasion of exotic annuals. On these lands, native forbs and grasses delayed or prevented from recovery by natural processes may require intervention through...

The role of silviculture in the active management of riparian zone vegetation in the Oregon Coast Range: a partnership between researchers and managers

Treesearch

Samuel S. Chan; Margaret David Bailey; Daniel Karnes; Robert Metzger; Walter W., Jr. Kastner

1997-01-01

Riparian plant communities are extremely diverse. Their structure and composition can affect fish and wildlife habitat, while trees and associated vegetation can provide sustainable sources of forest products. Management of riparian vegetation can greatly affect these values. Little information exists however, about the consequences of actively managing riparians to...

Growth, gas exchange, and root respiration of Quercus rubra seedlings exposed to low root zone temperatures in solution culture

Treesearch

Kent G. Apostol; Douglass F. Jacobs; Barrett C. Wilson; K. Francis Salifu; R. Kasten Dumroese

2007-01-01

Spring planting is standard operational practice in the Central Hardwood Region, though little is known about potential impacts of low root temperature (RT) common during spring on establishment success of temperate deciduous forest tree species. The effects of low RTon growth, gas exchange, and root respiration following winter dormancy were studied in 1-year-old...

[The intensity of phytodetrite decomposition in Larch Forest of the permafrost zone in central Siberia].

PubMed

Prokushkin, S G; Prokushkin, A S; Sorokin, N D

2014-01-01

Based on the results of long-term investigations, quantitative assessment ofphytodetrite mineralization rates is provided. Their role in the biological cycle of larch stands growing in the permafrost zone of Central Evenkia is discussed. It is demonstrated that their destruction in the subshrub-sphagnum and cowberry-green moss larch stands is extremely slow, the plant litter contains the most cecalcitrant organic matter demonstrating the lowest decomposition coefficient of 0.03-0.04 year(-1), whereas fresh components of the plant litter have 3- to 4-fold higher values. An insignificant input of N and C from the analyzed mortmass to the soil has been registered. It has been revealed that the changes in N and C in the decomposition components are closely related to the quantitative dynamics (biomass) of microorganisms, such as hydrolytics and, especially, micromicetes.

Vegetation ecology and carbon sequestration potential of shrubs in tropics of Chhattisgarh, India.

PubMed

Jhariya, Manoj Kumar

2017-09-25

Tropical forests are well known to have great species diversity and contribute substantial share in terrestrial carbon (C) stocks worldwide. Shrubs are long-neglected life form in the forest ecosystem, playing many roles in the forest and human life. Shrub has great impact on vegetation attributes which in turn modify the C storage and capture. In the present investigation, an attempt has been made to explore the dynamics of shrub species in four fire regimes, viz. high, medium, low, and no fire zones of Bhoramdeo Wildlife Sanctuary of Kawardha forest division (Chhattisgarh), India. The variations in structure, diversity, biomass, productivity, and C sequestration potential in all the sites were quantified. The density and basal area of shrub varied from 1250 to 3750 individuals ha -1 and 2.79 to 4.92 m 2  ha -1 , respectively. The diversity indices showed that the value of Shannon index was highest in medium fire zone (3.77) followed by high, low, and no fire zones as 3.25, 3.12, and 2.32, respectively. The value of Simpson's index or concentration of dominance (Cd) ranged from 0.08 to 0.20, species richness from 0.56 to 1.58, equitability from 1.41 to 1.44, and beta diversity from 1.50 to 4.20, respectively. The total biomass and C storage ranged from 6.82 to 15.71 and from 2.93 to 6.76 t ha -1 , respectively. The shrub density, importance value index (IVI), and abundance to frequency ratio (A/F) significantly correlated between high fire and medium fire zone. The basal area was found to be significantly positively correlated between high fire and medium fire, and low and no fire zones, respectively. Two-way cluster analysis reflected various patterns of clustering due to influence of the forest fire which showed that some species have distant clustering while some have smaller cluster. Principal component analysis (PCA) reflects variable scenario with respect to shrub layer. Ventilago calyculata and Zizyphus rotundifolia showed higher correlation between themselves in terms of basal area (BA). The total shrub production was 1.59-3.53 t ha -1  year -1 while the C sequestration potential of 0.71-1.57 t ha -1  year -1 under different fire regimes. Shrub community in the medium fire zone reflected higher productivity and higher C sequestration in comparison to other fire zone. Among the different plant parts, the biomass accumulation ratio was highest in the root of shrub community among various fire regimes. Screening of species for restoration and different land-use pattern on the basis of biomass accumulation and carbon sequestering potential would be an effective strategy for decision-making in sustainable forest management.

Disturbance of Dabao highway construction on plant species and soil nutrients in Longitudinal Range Gorge Region (LRGR) of Southwestern China.

PubMed

Cui, Baoshan; Zhao, Shuqing; Zhang, Kejiang; Li, Shaocai; Dong, Shikui; Bai, Junhong

2009-11-01

The disturbance of highway construction upon surrounding vulnerable ecosystems is a common threat in the Longitudinal Range Gorge Region of southwestern China. We evaluated the disturbance of highway on plant species richness and diversity and soil nutrients from adjacent to the highway to 300 m upslope and 100 m downslope in forests and grasslands by setting 12 belt transects in forests and grasslands (six belt transects and six control belt transects, respectively). The results showed that there were some significant variances in belt transects with respective control belt transects for species richness and diversity in both forests and grasslands. Species richness and diversity of trees were lower within a 50-m distance from the highway and more noticeable on the downslope portion. Species richness and diversity of shrubs and herbs appeared higher near highway edge. Both species richness and diversity of herbs were similar in forests. In addition, exotic species, such as Eupatorium adenophorum, were further from the road and more widely dispersed in grasslands. Soil nutrients except total potassium (TK) were lower in the downslope area adjacent to highway edge and showed a significant increase with increasing distance from the highway in both forests and grasslands. This indicates that grasslands acted as microhabitats for exotic species and are more easily to be invaded than forests, especially if disturbed. Once destroyed, plant species and soil nutrients will require a significant amount of time to be restored to control levels. This work illustrates that the effects extend considerably to distances upslope and downslope from the construction site. Given that these changes occurred relatively quickly, the study suggests that the environmental "footprint" grows far beyond the road and adjacent zone of disruption.

Attributing the effects of climate on phenology change suggests high sensitivity in coastal zones

NASA Astrophysics Data System (ADS)

Seyednasrollah, B.; Clark, J. S.

2015-12-01

The impact of climate change on spring phenology depends on many variables that cannot be separated using current models. Phenology can influence carbon sequestration, plant nutrition, forest health, and species distributions. Leaf phenology is sensitive to changes of environmental factors, including climate, species composition, latitude, and solar radiation. The many variables and their interactions frustrate efforts to attribute variation to climate change. We developed a Bayesian framework to quantify the influence of environment on the speed of forest green-up. This study presents a state-space hierarchical model to infer and predict change in forest greenness over time using satellite observations and ground measurements. The framework accommodates both observation and process errors and it allows for main effects of variables and their interactions. We used daily spaceborne remotely sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS) to quantify temporal variability in the enhanced vegetation index (EVI) along a habitat gradient in the Southeastern United States. The ground measurements of meteorological parameters are obtained from study sites located in the Appalachian Mountains, the Piedmont and the Atlantic Coastal Plain between years 2000 and 2015. Results suggest that warming accelerates spring green-up in the Coastal Plain to a greater degree than in the Piedmont and Appalachian. In other words, regardless of variation in the timing of spring onset, the rate of greenness in non-coastal zones decreases with increasing temperature and hence with time over the spring transitional period. However, in coastal zones, as air temperature increases, leaf expansion becomes faster. This may indicate relative vulnerability to warming in non-coastal regions where moisture could be a limiting factor, whereas high temperatures in regions close to the coast enhance forest physiological activities. Model predictions agree with the remotely sensed observations of the enhanced vegetation index. These findings could be used in forest managements for identifying vulnerable forests based on their habitat type and hydrological status.

Denitrification capacity and greenhouse gas emissions of soils in channelized and restored reaches along an Alpine river corridor

NASA Astrophysics Data System (ADS)

Shrestha, Juna; Niklaus, Pascal; Samaritani, Emanuela; Frossard, Emmanuel; Tockner, Klement; Luster, Jörg

2010-05-01

In order to assess the effects of river restoration on water and air quality, the biogeochemical functions of channelized and restored river reaches have to be quantified. The objective of this study was to compare denitrification potential and greenhouse gas emissions of functional processing zones (FPZ) in a channelized and a recently restored reach of the alpine river Thur in north-eastern Switzerland. The study was part of the project cluster RECORD of the ETH domain, Switzerland, which was initiated to increase the mechanistic understanding of coupled hydrological and ecological processes in river corridors. The denitrification potential represents an important aspect of the soil filter function related to water quality. Besides, it also contributes to the emission of greenhouse gases. Extensively used pasture growing on a sandy loam is the characteristic FPZ of the channelized section. The restored section encompasses five FPZ: (i) bare gravel bars sparsely colonized by plants, (ii) gravel bars densely colonized by grass (mainly canary reed grass with up to 80 cm sandy deposits), (iii) mixed forest dominated by ash and maple, (iv) riparian forest dominated by willow (Salix alba), (v) older overbank sediments stabilized during restoration with young willows separating the forests from the river-gravel bar system (willow bush). The FPZ were sampled in January, April, August and October 2009. In addition, in June and July 2009 two flood events were monitored in the restored section with more frequent samplings. At each date, topsoil samples were collected in each FPZ (four replicates per samples) and analyzed for denitrifier enzyme activity (DEA). In addition, gas samples were taken in-situ using the closed chamber technique to measure soil respiration as well as N2O and CH4 fluxes. In all FPZ, the denitrification potential was mainly governed by soil moisture. It was highest in the willow forest exhibiting low spatial variability. The DEA in pasture, grass zone, willow bush and mixed forest exhibited intermediate levels. Spatial variability was higher in the grass zone compared to other FPZs especially during the flooding events when denitrification hot spots occurred in this zone. In the gravel zone DEA was high when saturated slowly - as during a minor flood -, while it was low under dry conditions as well as during saturation following a major flood. The N2O emission rate was low in all FPZ throughout the year, except during few hot moments (i.e. in grass FPZ two weeks after major summer flood events and in grass and willow bush zone during winter. In conclusion, replacing a rather homogeneous floodplain by a spatially complex and temporally dynamic mosaic of FPZ of different succession stages (gravel bars with a varying degree of plant colonization and cover by fresh overbank sediments) has not led to fundamental changes in denitrification potential of the river floodplain. It is rather the shift from a homogeneously distributed filter function to a filter function mainly located in spatially and temporally defined hot spots. However, this change appears to be coupled to increased trace greenhouse gas emissions (methane and nitrous oxide) from certain hot spots. In addition, the study confirms the high denitrification potential of advanced stable wetlands as represented by the willow forest.

Effects of past logging and grazing on understory plant communities in a montane Colorado forest

USGS Publications Warehouse

Fornwalt, P.J.; Kaufmann, M.R.; Huckaby, L.S.; Stohlgren, T.J.

2009-01-01

Throughout Pinus ponderosa-Pseudotsuga menziesii forests of the southern Colorado Front Range, USA, intense logging and domestic grazing began at the time of Euro-American settlement in the late 1800s and continued until the early 1900s. We investigated the long-term impacts of these settlement-era activities on understory plant communities by comparing understory composition at a historically logged and grazed site to that of an environmentally similar site which was protected from past use. We found that species richness and cover within functional groups rarely differed between sites in either upland or riparian areas. Multivariate analyses revealed little difference in species composition between sites on uplands, though compositional differences were apparent in riparian zones. Our findings suggest that settlement-era logging and grazing have had only minor long-term impacts on understories of upland Front Range P. ponderosa-P. menziesii forests, though they have had a greater long-term influence on riparian understories, where these activities were likely the most intense. ?? 2008 Springer Science+Business Media B.V.

California tree seed zones

Treesearch

John M. Buck; Ronald S. Adams; Jerrold Cone; M. Thompson Conkle; William J. Libby; Cecil J. Eden; Michel J. Knight

1970-01-01

California forest tree seed zones were established originally by Fowells (1946), with revisions proposed by Roy (1963) and Schubert (1966). The Forest Tree Seed Committee of the Northern California Section, Society of American Foresters, has revised the original zones and updated the recording system described in the earlier reports. Fowells' (1946) Research Note...

Physical, chemical, and biological impacts of intensive forest management on streams draining watersheds in the coastal plain of Alabama

Treesearch

J.L. Michael; S.S. Ruiz-Cordova

2006-01-01

Five watersheds drained by first-order streams and containing timber that was 80+ years old were selected to study the impacts of clearcutting and planting site preparation on water quality in the presence and absence of streamside management zones (SMZs). One watershed was maintained as a reference with no treatment while the remaining 4 were clear cut harvested. Two...

Using an Integrated Hydrologic Model to Assess the Ecohydrological Impacts of Change on a Mountain Headwaters Critical Zone

NASA Astrophysics Data System (ADS)

Collins, C.; Maxwell, R. M.; Visser, A.

2016-12-01

The critical zone is the region of the Earth's crust where hydrogeology, ecology, and climate interact. As many critical zone processes are fundamental, the significance of studying critical zone processes goes beyond understanding the local ecohydrological setting. Therefore studying critical zone governing processes requires an interdisciplinary approach that integrates simulation and observation. In this study, a high-resolution integrated hydrologic model, ParFlow-CLM, was developed for the Providence Creek watershed. Providence Creek is a highly instrumented critical zone observatory (CZO) located in the southern Sierra Nevada Mountains, a region currently experiencing a range of short-term responses (i.e. tree mortality) to a severe four-year drought. Sources of plant water use, pathways and residence times of water through the subsurface are identified using a suite of isotopic signatures and numerical particle tracking. Implications of using a fully coupled integrated hydrologic model accompanied by tracer analysis include better understanding of water partitioning and water storage in the regolith and vegetation water use during drought time conditions. The importance of subsurface storage, plant available water and lateral flow during the 2012-2015 drought to mitigate vegetation stress are addressed and verified against observed tree mortality. The stream flow response to tree mortality in the aftermath of the drought, analogous to the Colorado Mountain Pine Beetle case, provides insight into the potential effects of proposed forest management practices.

Spatial variation in the storages and age-related dynamics of forest carbon sequestration in different climate zones-evidence from black locust plantations on the Loess Plateau of China.

PubMed

Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

2015-01-01

Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China's Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha-1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha-1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha-1 to 28.4 Mg C ha-1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration.

Transformation of soil and vegetable conditions at oil production territories

NASA Astrophysics Data System (ADS)

Gatina, Evgeniia

2017-04-01

On the territory of modern oil production soil, vegetation, ecosystem conditions of the environment are significantly transformed. Researches have been conducted on the oil production territories located in a boreal coniferous forest natural zone from 2005 to 2015. Standard geobotanical and soil methods are used. Mechanical destruction of a plant cover, change of the water conditions, intake of oil products and salty waters in ecosystems, pollution of the atmosphere are considered as the major technology-related factors defining transformation of land ecosystems at operation of the oil field. Under the mechanical destruction of a plant cover the pioneer plant communities are formed. These communities are characterized by most reduced specific wealth with prevalence of types of meadow groups of plants and presence of types of wetland groups of plants. The biodiversity of biocenosis which are affected linear infrastructure facilities of oil production territories and change of the water conditions, decreases. It is observed decrease in species wealth, simplification of structure of communities. Under the salting of soils in ecosystems there is a decrease species diversity of communities to prevalence nitrophilous and meadow plant species. At the increased content of organic substances in the soils that is a consequence of intake of oil products, is characteristic increase in specific richness of communities, introduction of types of wetland and oligotrophic groups of plants in forest communities. Influence depends on distance to an influence source. In process of removal from a source of atmospheric pollution in forest communities there is a decrease in species diversity and complication of structure of community. It is caused by introduction of types of meadow groups of plants in ecotone sites of the forest communities located near a source of influence and restoration of structural features of forest communities in process of removal from an influence source. Operation of oil fields leads to introduction of the synanthropes relating to meadow and wetland groups of plants. Transformation depends on loading time. At the initial stage of operation of the oil field the synantropization of a plant cover leads to increase in species diversity. At long technogenic loading decrease in values of indexes of a biodiversity due to oppression of native species of plants is observed. Technology-related influence of oil fields is a regional factor of change of specific structure of plant communities. Modern oil production has to be followed by purposeful formation of the operated natural and technology-related ecosystems with adjustable parameters and higher stability in relation to a complex of technogenic oil-field influence.

Landuse legacies of old-field succession and soil structure at the Calhoun Criticl Zone Observatory in SC, USA.

NASA Astrophysics Data System (ADS)

Brecheisen, Z. S.; Richter, D. D., Jr.; Callaham, M.; Carrera-Martinez, R.; Heine, P.

2017-12-01

The pre-colonial Southern Piedmont was an incredibly stable CZ with erosion rates between 0.35-3m/Myr on a 4th order interfluve. With soils and saprolite weathered up to 30m in total depth bedrock with multi-million year residence times under continual forest cover prior to widespread agricultural disturbance. With this biogeomorphic stability came time for soil macroporosity and soil structure to be established and maintained by the activities of soil fauna, plant root growth and death, and tree-fall tip-up events serving to continually mix and aerate the soil. Greatly accelerated surficial agricultural erosion (ca. 1750-1930) has fundamentally altered the Calhoun Critical Zone Observatory forest community dynamics aboveground and the soil structure, hydrology, and biogeochemistry belowground. The arrival of the plow to the Southern Piedmont marked the destruction of soil structure, macropore networks, and many of the macroinvertebrate soil engineers. This transformation came via forest clearing, soil tilling, compaction, and wholesale soil erosion, with the region having lost an estimated average of 18cm of soil across the landscape. In the temporal LULC progression from hardwood forests, to cultivated farms, to reforestation, secondary forest soil structure is expected to remain altered compared to the reference hardwood ecosystems. The research presented herein seeks to quantify CZ soil structure regeneration in old-field pine soil profiles' Ksat, aggregation, texture, macro-invertebrates, and direct measurements of topsoil porosity using X-ray computed tomography analysis on 15cm soil cores.

Variation in mangrove forest structure and sediment characteristics in Bocas del Toro, Panama

USGS Publications Warehouse

Lovelock, C.E.; Feller, Ilka C.; McKee, K.L.; Thompson, R.

2005-01-01

Mangrove forest structure and sediment characteristics were examined in the extensive mangroves of Bocas del Toro, Republic of Panama. Forest structure was characterized to determine if spatial vegetation patterns were repeated over the Bocas del Toro landscape. Using a series of permanent plots and transects we found that the forests of Bocas del Toro were dominated by Rhizophora mangle with very few individuals of Avicennia germinans and Laguncularia racemosa. Despite this low species diversity, there was large variation in forest structure and in edaphic conditions (salinity, concentration of available phosphorus, Eh and sulphide concentration). Aboveground biomass varied 20-fold, from 6.8 Mg ha-1 in dwarf forests to 194.3 Mg ha-1 in the forests fringing the land. But variation in forest structure was predictable across the intertidal zone. There was a strong tree height gradient from seaward fringe (mean tree height 3.9 m), decreasing in stature in the interior dwarf forests (mean tree height 0.7 m), and increasing in stature in forests adjacent to the terrestrial forest (mean tree height 4.1 m). The predictable variation in forest structure emerges due to the complex interactions among edaphic and plant factors. Identifying predictable patterns in forest structure will aid in scaling up the ecosystem services provided by mangrove forests in coastal landscapes. Copyright 2005 College of Arts and Sciences.

[Effects of forest gap size and light intensity on herbaceous plants in Pinus koraiensis-dominated broadleaved mixed forest].

PubMed

Duan, Wen-Biao; Wang, Li-Xia; Chen, Li-Xin; Du, Shan; Wei, Quan-Shuai; Zhao, Jian-Hui

2013-03-01

1 m x 1 m fixed quadrats were parallelly arranged with a space of 2 m in each of six forest gaps in Pinus koraiensis-dominated broadleaved mixed forest, taking the gap center as the starting point and along east-west and south-north directions. In each quadrat, the coverage and abundance of herbaceous plants at different height levels were investigated by estimation method in June and September 2011, and the matrix characteristics within the quadrats were recorded. Canopy analyzer was used to take fish-eye photos in the selected overcast days in each month from June to September, 2011, and the relative light intensity was calculated by using Gap Light Analyzer 2.0 software. The differences in the relative light intensity and herbaceous plants coverage and richness between different gaps as well as the correlations between the coverage of each species and the direct light, diffuse light, and matrix were analyzed. The results showed that in opening areas and under canopy, the relative light intensity in large gaps was higher than that in small gaps, and the variation ranges of diffuse light and direct light from gap center to gap edge were bigger in large gaps than in small gaps. The direct light reaching at the ground both in large gaps and in small gaps was higher in the north than in the south direction. In the Z1, Z2, Z3, and Z4 zones, both the coverage and the richness of herbaceous plants were larger in large gaps than in small gaps, and the differences of species richness between large and small gaps reached significant level. The coverage of the majority of the herbaceous plants had significant correlations with diffuse light and matrix, and only the coverage of a few herbaceous plants was correlated with direct light.

Role of Native and Exotic Earthworms in Plant Biopolymer Dynamics in Forest Soil

NASA Astrophysics Data System (ADS)

Filley, Timothy

2010-05-01

Many forests within northern North America are experiencing the introduction of earthworms for the first time, presumably since before the last major glaciation. Forest dynamics are undergoing substantial changes because of the activity of the mainly European lumbricid species. Documented losses in litter layers, expansion of A-horizons, loss of the organic horizon, changes in fine root density, and shifts in microbial populations have all been documented in invaded zones. Two free air CO2 enrichment (FACE) forest experiments (aspen FACE at Rhinelander, Wisconsin and sweet gum FACE at Oak Ridge National Lab, Tennessee) lie within the zones of invasion and exhibit differences in amounts of exotic and native species as well as endogeic (predominantly mineral soil dwelling) and epigeic (litter and organic matter horizon dwelling) types. Considerations of carbon accrual dynamics and relative input of above vs. below ground plant input in these young successional systems do not consider the potential impact of these ecosystem engineers. We investigated the impact of earthworm activity by tracking the relative abundance and stable carbon isotope compositions of lignin and substituted fatty acids extracted from isolated earthworms and their fecal pellets and from host soils. Indications of root vs leaf input to earthworm casts and fecal matter were derived from differences in the chemical composition of cutin, suberin, and lignin. The isotopically depleted CO2 used in FACE and the resulting isotopically depleted plant organic matter afford an excellent opportunity to assess biopolymer-specific turnover dynamics. We find that endogeic species are proportionately more responsible for fine root cycling while some epigeic species are responsible for microaggregation of foliar cutin. CSIA of fecal pellet lignin and SFA indicates how these biopolymer pools can be derived from variable sources, roots, background soil, foliar tissue within one earthworm. Additionally, CSIA indicates the distinct roles that different earthworm types have in "aging" surface soil biopolymer pools through encapsulation and upward transport of deeper soil carbon, and "freshening" deeper soil biopolymer pools through downward transport of surface carbon to deeper layers,. As earthworm species abundance and activity are not is steady state in many forests, the role of these important invertebrates should be more considered when assessing the changing soil state.

Spatial Variation in the Storages and Age-Related Dynamics of Forest Carbon Sequestration in Different Climate Zones—Evidence from Black Locust Plantations on the Loess Plateau of China

PubMed Central

Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

2015-01-01

Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China’s Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha−1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha−1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha−1 to 28.4 Mg C ha−1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration. PMID:25799100

36 CFR 13.1304 - Ice fall hazard zones.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Ice fall hazard zones. 13.1304 Section 13.1304 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1304 Ice fall hazard zones. Entering an ice fall hazard zone is prohibited. These zones will...

36 CFR 13.1304 - Ice fall hazard zones.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Ice fall hazard zones. 13.1304 Section 13.1304 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1304 Ice fall hazard zones. Entering an ice fall hazard zone is prohibited. These zones will...

36 CFR 13.1304 - Ice fall hazard zones.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Ice fall hazard zones. 13.1304 Section 13.1304 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1304 Ice fall hazard zones. Entering an ice fall hazard zone is prohibited. These zones will...

36 CFR 13.1304 - Ice fall hazard zones.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Ice fall hazard zones. 13.1304 Section 13.1304 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1304 Ice fall hazard zones. Entering an ice fall hazard zone is prohibited. These zones will...

Vegetation, climate and fire-dynamics in East Africa inferred from the Maundi crater pollen record from Mt Kilimanjaro during the last glacial-interglacial cycle

NASA Astrophysics Data System (ADS)

Schüler, Lisa; Hemp, Andreas; Zech, Wolfgang; Behling, Hermann

2012-04-01

The pollen, charcoal and sedimentological record from the Maundi crater, located at 2780 m elevation on the south-eastern slope of Mt Kilimanjaro, is one of the longest terrestrial records in equatorial East Africa, giving an interesting insight into the vegetation and climate dynamics back to the early last Glacial period. Our sediment record has a reliable chronology until 42 ka BP. An extrapolation of the age-depth model, as well as matching with other palaeo-records from tropical East Africa, suggest a total age of about 90 ka BP at the bottom of the record. During the last Glacial the distribution as well as the composition of the vegetation belts classified as colline savanna, submontane woodland, montane forest, ericaceous belt, and alpine vegetation changed. The early last Glacial is characterized by high amounts of Poaceae and Asteraceae pollen suggesting a climatically dry but stable phase. Based on the absence of pollen grains in samples deposited around 70 ka BP, we assume the occurrence of distinct drought periods. During the pre-LGM (Last Glacial Maximum) a higher taxa diversity of the ericaceous and montane zone is recorded and suggests a spread of forest and shrub vegetation, thus indicating a more humid period. The taxa diversity increases steadily during the recorded time span. The decent of vegetation zones indicate dry and cold conditions during the LGM and seem to have been detrimental for many taxa, especially those of the forest vegetation; however, the early last Glacial seems to have been markedly drier than the LGM. The reappearance of most of the taxa (most importantly Alchemilla, Araliaceae, Dodonea, Hagenia, Ilex, Myrsine, Moraceae, Piperaceae) during the deglacial and Holocene period suggest a shift into humid conditions. An increase in ferns and the decrease in grasses during the Holocene also indicate increasing humidity. Fire played an important role in controlling the development and elevation of the ericaceous zone and the tree line. During the Holocene no increased anthropogenic impact around the Maundi crater can be observed, since neither higher fire activity nor a spread of hemerophilic plants is recorded. This pollen archive reveals shifts in the upper vegetation zones (ericaceous zone and montane forest zone) of at least 1100 m but underlines the role of Mt Kilimanjaro as a glacial refuge for montane forest species similar to that of the Eastern Arc Mountains.

Determination of pumper truck intervention ratios in zones with high fire potential by using geographical information system

NASA Astrophysics Data System (ADS)

Aricak, Burak; Kucuk, Omer; Enez, Korhan

2014-01-01

Fighting forest fires not only depends on the forest type, topography, and weather conditions, but is also closely related to the technical properties of fire-fighting equipment. Firefighting is an important part of fire management planning. However, because of the complex nature of forests, creating thematic layers to generate potential fire risk maps is difficult. The use of remote sensing data has become an efficient method for the discrete classification of potential fire risks. The study was located in the Central District of the Kastamonu Regional Forest Directorate, covering an area of 24,320 ha, 15,685 ha of which is forested. On the basis of stand age, crown closure, and tree species, the sizes and distributions of potential fire risk zones within the study area were determined using high-resolution GeoEye satellite imagery and geographical information system data. The status of pumper truck intervention in zones with high fire risk and the sufficiency of existing forest roads within an existing forest network were discussed based on combustible matter characteristics. Pumper truck intervention was 83% for high-risk zones, 79% for medium-risk zones, and 78% for low-risk zones. A pumper truck intervention area map along existing roads was also created.

Defining fire environment zones in the boreal forests of northeastern China.

PubMed

Wu, Zhiwei; He, Hong S; Yang, Jian; Liang, Yu

2015-06-15

Fire activity in boreal forests will substantially increase with prolonged growing seasons under a warming climate. This trend poses challenges to managing fires in boreal forest landscapes. A fire environment zone map offers a basis for evaluating these fire-related problems and designing more effective fire management plans to improve the allocation of management resources across a landscape. Toward that goal, we identified three fire environment zones across boreal forest landscapes in northeastern China using analytical methods to identify spatial clustering of the environmental variables of climate, vegetation, topography, and human activity. The three fire environment zones were found to be in strong agreement with the spatial distributions of the historical fire data (occurrence, size, and frequency) for 1966-2005. This paper discusses how the resulting fire environment zone map can be used to guide forest fire management and fire regime prediction. Copyright © 2015 Elsevier B.V. All rights reserved.

Monitoring plant tissue nitrogen isotopes to assess nearshore inputs of nitrogen to Lake Crescent, Olympic National Park, Washington

USGS Publications Warehouse

Cox, Stephen E.; Moran, Patrick W.; Huffman, Raegan L.; Fradkin, Steven C.

2016-05-31

Mats of filamentous-periphytic algae present in some nearshore areas of Lake Crescent, Olympic National Park, Washington, may indicate early stages of eutrophication from nutrient enrichment of an otherwise highly oligotrophic lake. Natural abundance ratios of stable isotopes of nitrogen (δ15N) measured in plant tissue growing in nearshore areas of the lake indicate that the major source of nitrogen used by these primary producing plants is derived mainly from atmospherically fixed nitrogen in an undeveloped forested ecosystem. Exceptions to this pattern occurred in the Barnes Point area where elevated δ15N ratios indicate that effluent from septic systems also contribute nitrogen to filamentous-periphytic algae growing in the littoral zone of that area. Near the Lyre River outlet of Lake Crescent, the δ15N of filamentous-periphytic algae growing in close proximity to the spawning areas of a unique species of trout show little evidence of elevated δ15N indicating that nitrogen from on-site septic systems is not a substantial source of nitrogen for these plants. The δ15N data corroborate estimates that nitrogen input to Lake Crescent from septic sources is comparatively small relative to input from motor vehicle exhaust and vegetative sources in undeveloped forests, including litterfall, pollen, and symbiotic nitrogen fixation. The seasonal timing of blooms of filamentous-periphytic algal near the lake shoreline is also consistent with nitrogen exported from stands of red alder trees (Alnus rubra). Isotope biomonitoring of filamentous-periphytic algae may be an effective approach to monitoring the littoral zone for nutrient input to Lake Crescent from septic sources.

Pollinators and Other Flying Insects inside and outside the Fukushima Evacuation Zone.

PubMed

Yoshioka, Akira; Mishima, Yoshio; Fukasawa, Keita

2015-01-01

Following the accident at the Fukushima Daiichi nuclear power plants in 2011, a large evacuation zone was imposed in an area where residents had historically managed forests and farmlands. Thus, the human activities that had maintained biodiversity and ecosystem services in the zone were discontinued. Such change can affect insects, a biodiversity component that is relatively tolerant to radiation exposure. In this study, we investigated flying insects, including pollinators, important ecosystem providers inside and outside the zone, using Malaise traps. The results showed that the number of individuals of Xylocopa appendiculata, the largest Apidae species in the region, was significantly lower inside the evacuation zone than outside it, whereas those of other insects were not lower significantly. Although we suggest that flying insects and their ecosystem services (i.e., benefits from them such as pollination) 3 years after the disaster were not critically impacted, it is important to monitor the long-term effects of the evacuation in the future.

Modeling the Influence of Dynamic Zoning of Forest Harvesting on Ecological Succession in a Northern Hardwoods Landscape

Treesearch

Patrick A. Zollner; Eric J. Gustafson; Hong S. He; Volker C. Radeloff; David J. Mladenoff

2005-01-01

Dynamic zoning (systematic alteration in the spatial and temporal allocation of even-aged forest management practices) has been proposed as a means to change the spatial pattern of timber harvest across a landscape to maximize forest interior habitat while holding timber harvest levels constant. Simulation studies have established that dynamic zoning strategies...

Novelty and its ecological implications to dry forest functioning and conservation

Treesearch

Ariel Lugo; Heather Erickson

2017-01-01

Tropical and subtropical dry forest life zones support forests with lower stature and species richness than do tropical and subtropical life zones with greater water availability. The number of naturalized species that can thrive and mix with native species to form novel forests in dry forest conditions in Puerto Rico and the US Virgin Islands is lower than in other...

Ecohydrological Consequences of Critical Zone Structure in the Franciscan Formation, Northern California Coast Ranges

NASA Astrophysics Data System (ADS)

Hahm, W. J.; Dietrich, W. E.; Dawson, T. E.; Lovill, S.; Rempe, D.

2016-12-01

Water availability regulates ecosystem function, particularly in seasonally dry climates where lack of moisture in the growing season acts as an ecological bottleneck. Water within hillslopes is extracted by plants during transpiration and also delivered to streams to support baseflow for riparian ecosystems and human use. How water is stored and then released from hillslopes is strongly influenced by the structure of the critical zone (CZ) that emerges from the complex interaction of lithology, climate, and tectonics. Here we show how contrasting CZ development has extreme ecohydrological consequences in the seasonally dry climate of the Northern California Coast Ranges. To explore how the CZ transmits and stores water, we studied hydrologic dynamics at two sites with similar climate across belts of the Franciscan Formation in the Eel River CZO. We monitored plant water use, precipitation inputs and stream runoff, groundwater and vadose zone moisture dynamics and documented near-surface hydraulic conductivity and runoff-generation processes. We investigated CZ structure via boreholes and geophysical methods. We find that CZ thickness determines the extent to which hillslopes `shed' or `store' wet season precipitation, and fundamentally controls the structure of plant communities and summer low-flows. In a climate where winter precipitation regularly exceeds 2000 mm, the thin CZ of the sheared argillite matrix Central belt rapidly fills, resulting in wet-season saturation overland flow that drives flashy winter runoff in channels that then quickly run dry in the early summer. The maximum unsaturated moisture storage of approximately 200 mm is sufficient to host an ecologically diverse yet sparsely forested oak savanna. In contrast, the thick CZ of the interbedded argillite and greywacke Coastal belt stores up to 600 mm of winter precipitation in the unsaturated zone and a seasonal groundwater system within fractured bedrock provides year-round flow to channels, supporting dense mixed coniferous-broadleaf evergreen forest and native resident salmonids. These findings underscore the importance of understanding how the structure of the CZ develops by directly pairing hillslope moisture storage and release to the composition and resilience of terrestrial and aquatic ecosystems.

Evidence in support of the role of disturbance vegetation for women’s health and childcare in Western Africa

PubMed Central

2014-01-01

Background In savannah-dominated Bénin, West Africa, and forest-dominated Gabon, Central Africa, plants are a major source of healthcare for women and children. Due to this high demand and the reliance on wild populations as sources for medicinal plants, overharvesting of African medicinal plants is a common concern. Few studies in Western Africa, however, have assessed variations in harvest patterns across different ecological zones and within local communities. Methods We investigated which vegetation types women accessed to harvest medicinal plants by conducting 163 questionnaires with market vendors and women from urban and rural communities. We made botanical vouchers of cited species and collected information on their vegetation type and cultivation status. Results Secondary vegetation was a crucial asset; over 80% of the 335 Beninese and 272 Gabonese plant species came from disturbance vegetation and home gardens. In Bénin, access to trade channels allowed female market vendors to use more vulnerable species than rural and urban women who harvested for personal use. In Gabon, no relationship was found between vulnerable plant use and informant type. Conclusions This study highlights the underemphasized point that secondary vegetation is an asset for women and children’s health in both savanna-dominated and forest-dominated landscapes. The use of disturbance vegetation demonstrates women’s resilience in meeting healthcare needs in the limited amount of space that is available to them. Species of conservation concern included forest species and savanna trees sold at markets in Bénin, especially Xylopia aethiopica, Khaya senegalensis, and Monodora myristica, and the timber trees with medicinal values in Gabon, such as Baillonella toxisperma. PMID:24885805

Trait variations of ground flora species disentangle the effects of global change and altered land-use in Swedish forests during 20 years.

PubMed

Hedwall, Per-Ola; Brunet, Jörg

2016-12-01

Northern forest ecosystems are exposed to a range of anthropogenic processes including global warming, atmospheric deposition, and changing land-use. The vegetation of northern forests is composed of species with several functional traits related to these processes, whose effects may be difficult to disentangle. Here, we combined analyses of spatio-temporal dynamics and functional traits of ground flora species, including morphological characteristics, responses to macro- and microclimate, soil conditions, and disturbance. Based on data from the Swedish National Forest Inventory, we compared changes in occurrence of a large number of ground flora species during a 20-year period (1994-2013) in boreal and temperate Sweden respectively. Our results show that a majority of the common ground flora species have changed their overall frequency. Comparisons of functional traits between increasing and declining species, and of trends in mean trait values of sample plots, indicate that current floristic changes are caused by combined effects of climate warming, nitrogen deposition and changing land-use. Changes and their relations with plant traits were generally larger in temperate southern Sweden. Nutrient-demanding species with mesotrophic morphology were favored by ongoing eutrophication due to nitrogen deposition in the temperate zone, while dwarf shrubs with low demands on nitrogen decreased in frequency. An increase of species with less northern and less eastern distribution limits was also restricted to temperate Sweden, and indicates effects of a moister and milder macroclimate. A trend toward dense plantation forests is mirrored by a decrease of light-demanding species in both vegetation zones, and a decrease of grassland species in the temperate zone. Although denser tree canopies may buffer effects of a warmer climate and of nitrogen deposition to some extent, traits related to these processes were weakly correlated in the group of species with changing frequency. Hence, our results indicate specific effects of these often confounded anthropogenic processes. © 2016 John Wiley & Sons Ltd.

The Zoning of Forest Fire Potential of Gulestan Province Forests Using Granular Computing and MODIS Images

NASA Astrophysics Data System (ADS)

Jalilzadeh Shadlouei, A.; Delavar, M. R.

2013-09-01

There are many vegetation in Iran. This is because of extent of Iran and its width. One of these vegetation is forest vegetation most prevalent in Northern provinces named Guilan, Mazandaran, Gulestan, Ardebil as well as East Azerbaijan. These forests are always threatened by natural forest fires so much so that there have been reports of tens of fires in recent years. Forest fires are one of the major environmental as well as economic, social and security concerns in the world causing much damages. According to climatology, forest fires are one of the important factors in the formation and dispersion of vegetation. Also, regarding the environment, forest fires cause the emission of considerable amounts of greenhouse gases, smoke and dust into the atmosphere which in turn causes the earth temperature to rise up and are unhealthy to humans, animals and vegetation. In agriculture droughts are the usual side effects of these fires. The causes of forest fires could be categorized as either Human or Natural Causes. Naturally, it is impossible to completely contain forest fires; however, areas with high potentials of fire could be designated and analysed to decrease the risk of fires. The zoning of forest fire potential is a multi-criteria problem always accompanied by inherent uncertainty like other multi-criteria problems. So far, various methods and algorithm for zoning hazardous areas via Remote Sensing (RS) and Geospatial Information System (GIS) have been offered. This paper aims at zoning forest fire potential of Gulestan Province of Iran forests utilizing Remote Sensing, Geospatial Information System, meteorological data, MODIS images and granular computing method. Granular computing is part of granular mathematical and one way of solving multi-criteria problems such forest fire potential zoning supervised by one expert or some experts , and it offers rules for classification with the least inconsistencies. On the basis of the experts' opinion, 6 determinative criterias contributing to forest fires have been designated as follows: vegetation (NDVI), slope, aspect, temperature, humidity and proximity to roadways. By applying these variables on several tentatively selected areas and formation information tables and producing granular decision tree and extraction of rules, the zoning rules (for the areas in question) were extracted. According to them the zoning of the entire area has been conducted. The zoned areas have been classified into 5 categories: high hazard, medium hazard (high), medium hazard (low), low hazard (high), low hazard (low). According to the map, the zoning of most of the areas fall into the low hazard (high) class while the least number of areas have been classified as low hazard (low). Comparing the forest fires in these regions in 2010 with the MODIS data base for forest fires, it is concluded that areas with high hazards of forest fire have been classified with a 64 percent precision. In other word 64 percent of pixels that are in high hazard classification are classified according to MODIS data base. Using this method we obtain a good range of Perception. Manager will reduce forest fire concern using precautionary proceeding on hazardous area.

Foresters' perceptions of windthrow dynamics in northern Minnesota riparian management zones

Treesearch

Jeremy C. Steil; Charles R. Blinn; Randy Kolka

2009-01-01

A survey was mailed to foresters in northern Minnesota to identify their perceptions of what conditions result in higher incidence of windthrow in riparian management zones (RMZ) where the upland has been clearcut. Results indicate that foresters think many variables impact windthrow, often interacting in complex ways. Foresters considered topographic exposure, species...

Evaluating the Effects of Different Vegetation Types on Necrophagous Fly Communities (Diptera: Calliphoridae; Sarcophagidae): Implications for Conservation

PubMed Central

Pereira de Sousa, José Roberto; Carvalho-Filho, Fernando da Silva; Juen, Leandro; Esposito, Maria Cristina

2016-01-01

The present study was conducted in five different phytogeographic zones of the Brazilian state of Maranhão, three of which (the Amazon Forest, Cerrado, and Palm Groves) are more heterogeneous, whereas the other two (Marshlands and Mangroves) are more homogeneous. In each zone, nine sites were visited for the collection of necrophagous flies using bait traps in 2010, 2011, and 2012. The calliphorid and sarcophagid communities observed at each site were compared in terms of species richness, composition, and abundance. The more heterogeneous zones had higher species richness, except in the case of the sarcophagids in the forest habitats. The calliphorids Chloroprocta idioidea (Robineau- Desvoidy, 1830), Mesembrinella bicolor (Fabricius, 1805), Hemilucilia semidiaphana (Rondani, 1850) and Lucilia eximia (Wiedemann, 1819) were more closely associated with the Cerrado, Palm Grove and Amazon Forest zones, and Chrysomya megacephala (Fabricius, 194) with the Mangrove. In the sarcophagids, Peckia (Euboettcheria) subducta (Lopes, 1935) and P. (Pattonella) palidipilosa (Curran & Walley, 1934) were associated with the Amazon Forest, and P. (Sarcodexia) lambens (Wiedemann, 1830) and Tricharaea (Sarcophagula) occidua (Fabricius, 1794) with the Palm Grove and Cerrado zones. In the calliphorids, the greatest dissimilarity was recorded between the Amazon Forest and the Mangrove and Lowland grassland zones. In the sarcophagids, by contrast, the greatest dissimilarities were recorded between the Amazon Forest and all the other four zones. In general, then, the phytogeographic zones with the highest environmental heterogeneity were characterized by the greatest species richness and abundance of necrophagous flies. PMID:27798664

A modified integrated NDVI for improving estimates of terrestrial net primary production

NASA Technical Reports Server (NTRS)

Running, Steven W.

1990-01-01

Logic is presented for a time-integrated NDVI that is modified by an AVHRR derived surface evaporation resistance factor sigma, and truncated by temperatures that cause plant dormancy, to improve environmental sensitivity. With this approach, NDVI observed during subfreezing temperatures is not integrated. Water stress-related impairment in plant activity is incorporated by reducing the effective NDVI at each integration with sigma, which is derived from the slope of the surface temperature to NDVI ratio for climatically similar zones of the scene. A comparison of surface resistance before and after an extended drought period for a 1200 sq km region of coniferous forest in Montana is presented.

Dynamics and mitigation of six pesticides in a "Wet" forest buffer zone.

PubMed

Passeport, Elodie; Richard, Benjamin; Chaumont, Cédric; Margoum, Christelle; Liger, Lucie; Gril, Jean-Joël; Tournebize, Julien

2014-04-01

Pesticide pollution is one of the main current threats on water quality. This paper presents the potential and functioning principles of a "Wet" forest buffer zone for reducing concentrations and loads of glyphosate, isoproturon, metazachlor, azoxystrobin, epoxiconazole, and cyproconazole. A tracer injection experiment was conducted in the field in a forest buffer zone at Bray (France). A fine time-scale sampling enabled to illustrate that interactions between pesticides and forest buffer substrates (soil and organic-rich litter layer), had a retarding effect on molecule transfer. Low concentrations were observed for all pesticides at the forest buffer outlet thus demonstrating the efficiency of "Wet" forest buffer zone for pesticide dissipation. Pesticide masses injected in the forest buffer inlet directly determined concentration peaks observed at the outlet. Rapid and partially reversible adsorption was likely the major process affecting pesticide transfer for short retention times (a few hours to a few days). Remobilization of metazachlor, isoproturon, desmethylisoproturon, and AMPA was observed when non-contaminated water flows passed through the forest buffer. Our data suggest that pesticide sorption properties alone could not explain the complex reaction mechanisms that affected pesticide transfer in the forest buffer. Nevertheless, the thick layer of organic matter litter on the top of the forest soil was a key parameter, which enhanced partially reversible sorption of pesticide, thus retarded their transfer, decreased concentration peaks, and likely increased degradation of the pesticides. Consequently, to limit pesticide pollution transported by surface water, the use of already existing forest areas as buffer zones should be equally considered as the most commonly implemented grass buffer strips.

Mycorrhizal networks and distance from mature trees alter patterns of competition and facilitation in dry Douglas-fir forests.

PubMed

Teste, François P; Simard, Suzanne W

2008-11-01

The distribution of dry Douglas-fir forests in western North America is expected to shift northward with climate change and disappear from the grassland interface in the southern interior of British Columbia. This shift may be accentuated by clearcutting, a common harvesting practice that aims to reduce the competitive effects of residual mature trees on new regeneration, but in so doing, ignores their facilitative effects. In this study, we investigated the net effects of competition from and facilitation by mature trees retained on harvested sites on seedling establishment in the dry interface Douglas-fir forests. We demonstrate that access to a mycorrhizal network (MN) and proximity to trees have important influences on seedling performance. On six sites, we established trenched plots around 24 mature Pseudotsuga menziesii var. glauca (Douglas-fir) trees, then planted Douglas-fir seedlings into four mesh treatments that served to restrict MN access (i.e., planted into mesh bags with 0.5-, 35-, or 250-microm pores, or without mesh) or into impermeable bags (grown in isolation) at four distances (0.5, 1.0, 2.5, or 5.0 m). Seedling survival tended to be greater and water stress lower where seedlings had full access to the MN. Seedling height, shoot biomass, needle biomass, and nutrient uptake peaked at 2.5-5.0 m from mature trees. Seedlings 0.5 m from mature trees had lower CO2 assimilation rates and wood delta(13)C compared to seedlings 5.0 m away. Competition for soil resources was highest near mature trees but facilitation was relatively greater at further distances, resulting in a zone of net benefit for seedlings. These results show that intraspecific tree-seedling interactions are both competitive and facilitative in dry Douglas-fir forests, and that they are spatially dependent. After disturbance, maintaining residual mature trees may be important for their beneficial regeneration zones.

Genetic variation and seed zones of Douglas-fir in the Siskiyou National Forest.

Treesearch

Robert K. Campbell; Albert I. Sugano

1993-01-01

Provisional seed zones and breeding zones were developed for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in the Siskiyou National Forest in southwestern Oregon. Zones were based on maps of genetic variation patterns obtained by evaluating genotypes of trees from 260 locations in the region. Genotypes controlling growth vigor and growth...

Vegetation map for the Hakalau Forest Unit of the Big Island National Wildlife Refuge Complex on the island of Hawai‘i

USGS Publications Warehouse

Jacobi, James D.

2017-01-01

This vegetation map was produced to serve as an updated habitat base for management of natural resources of the Hakalau Forest Unit (HFU) of the Big Island National Wildlife Refuge Complex (Refuge) on the island of Hawai‘i. The map is based on a vegetation map originally produced as part of the U.S. Fish and Wildlife Service’s Hawai‘i Forest Bird Survey to depict the distribution, structure, and composition of plant communities on the island of Hawai‘i as they existed in 1977. The current map has been updated to represent current conditions of plant communities in the HFU, based on WorldView 2 imagery taken in 2012 and very-high-resolution imagery collected by Pictometry International from 2010 to 2014. Thirty-one detailed plant communities are identified on this map, and fourteen of these units are found within the boundaries of HFU. Additionally, the mapped units can be displayed as five tree canopy cover units, three moisture zones units, eight dominant tree species units, and four habitat status units by choosing the various fields to group the units from the map attribute table. This updated map will provide a foundation for the refinement and tracking of management actions on the Refuge for the near future, particularly as the habitats in this area are subject to projected climate change.

Divergence of dominant factors in soil microbial communities and functions in forest ecosystems along a climatic gradient

NASA Astrophysics Data System (ADS)

Xu, Zhiwei; Yu, Guirui; Zhang, Xinyu; He, Nianpeng; Wang, Qiufeng; Wang, Shengzhong; Xu, Xiaofeng; Wang, Ruili; Zhao, Ning

2018-03-01

Soil microorganisms play an important role in regulating nutrient cycling in terrestrial ecosystems. Most of the studies conducted thus far have been confined to a single forest biome or have focused on one or two controlling factors, and few have dealt with the integrated effects of climate, vegetation, and soil substrate availability on soil microbial communities and functions among different forests. In this study, we used phospholipid-derived fatty acid (PLFA) analysis to investigate soil microbial community structure and extracellular enzymatic activities to evaluate the functional potential of soil microbes of different types of forests in three different climatic zones along the north-south transect in eastern China (NSTEC). Both climate and forest type had significant effects on soil enzyme activities and microbial communities with considerable interactive effects. Except for soil acid phosphatase (AP), the other three enzyme activities were much higher in the warm temperate zone than in the temperate and the subtropical climate zones. The soil total PLFAs and bacteria were much higher in the temperate zone than in the warm temperate and the subtropical zones. The soil β-glucosidase (BG) and N-acetylglucosaminidase (NAG) activities were highest in the coniferous forest. Except for the soil fungi and fungi-bacteria (F/B), the different groups of microbial PLFAs were much higher in the conifer broad-leaved mixed forests than in the coniferous forests and the broad-leaved forests. In general, soil enzyme activities and microbial PLFAs were higher in primary forests than in secondary forests in temperate and warm temperate regions. In the subtropical region, soil enzyme activities were lower in the primary forests than in the secondary forests and microbial PLFAs did not differ significantly between primary and secondary forests. Different compositions of the tree species may cause variations in soil microbial communities and enzyme activities. Our results showed that the main controls on soil microbes and functions vary in different climatic zones and that the effects of soil moisture content, soil temperature, clay content, and the soil N / P ratio were considerable. This information will add value to the modeling of microbial processes and will contribute to carbon cycling in large-scale carbon models.

Soil water nitrate concentrations in giant cane and forest riparian buffer zones

Treesearch

Jon E. Schoonover; Karl W. J. Williard; James J. Zaczek; Jean C. Mangun; Andrew D. Carver

2003-01-01

Soil water nitrate concentrations in giant cane and forest riparian buffer zones along Cypress Creek in southern Illinois were compared to determine if the riparian zones were sources or sinks for nitrogen in the rooting zone. Suction lysimeters were used to collect soil water samples from the lower rooting zone in each of the two vegetation types. The cane riparian...

Soils characterisation along ecological forest zones in the Eastern Himalayas

NASA Astrophysics Data System (ADS)

Simon, Alois; Dhendup, Kuenzang; Bahadur Rai, Prem; Gratzer, Georg

2017-04-01

Elevational gradients are commonly used to characterise vegetation patterns and, to a lesser extent, also to describe soil development. Furthermore, interactions between vegetation cover and soil characteristics are repeatedly observed. Combining information on soil development and easily to distinguish forest zones along elevational gradients, creates an added value for forest management decisions especially in less studied mountain regions. For this purpose, soil profiles along elevational gradients in the temperate conifer forests of Western and Central Bhutan, ranging from 2600-4000m asl were investigated. Thereby, 82 soil profiles were recorded and classified according to the World Reference Base for Soil Resources. Based on 19 representative profiles, genetic horizons were sampled and analysed. We aim to provide fundamental information on forest soil characteristics along these elevational transects. The results are presented with regard to ecological forest zones. The elevational distribution of the reference soil groups showed distinct distribution ranges for most of the soils. Cambisols were the most frequently recorded reference soil group with 58% of the sampled profiles, followed by Podzols in higher elevations, and Stagnosols, at intermediate elevations. Fluvisols occurred only at the lower end of the elevational transects and Phaeozems only at drier site conditions in the cool conifer dry forest zone. The humus layer thickness differs between forest zones and show a shift towards increased organic layer (O-layer) with increasing elevation. The reduced biomass productivity with increasing elevation and subsequently lower litter input compensates for the slow decomposition rates. The increasing O-layer thickness is an indicator of restrained intermixing of organic and mineral components by soil organisms at higher elevation. Overall, the soil types and soil characteristics along the elevational gradient showed a continuous and consistent change, instead of abrupt changes. We interpret these as manifestations of changes of temperature and precipitation with elevation which also drives forest zonation in these least anthropogenically influenced forest ecosystems. The elevational distribution of forest zones is correlated with the distribution of soil types and thus also reflects soil characteristics.

Modern pollen and stomate deposition in lake surface sediments from across the treeline on the Kola Peninsula, Russia.

PubMed

Gervais, B R.; MacDonald, G M.

2001-04-01

We sampled and analyzed surface sediments from 31 lakes along a latitudinal transect crossing the coniferous treeline on the Kola Peninsula, Russia. The major vegetation zones along the transect were tundra, birch-forest tundra, pine-forest tundra, and forest. The results indicate that the major vegetation types in our study area have distinct pollen spectra. Sum-of-squares cluster analysis and principal components analysis (PCA) groupings of pollen sites correspond to the major vegetation zones. PCA ordination of taxa indicates that the first axis separates taxa typical of the forest zone (Pinus, Picea) from taxa typical of tundra and forest-tundra zones (Polypodiaceae, Ericaceae, and Betula). The current position of the coniferous treeline, defined in our region by Pinus sylvestris, occurs roughly where Pinus pollen values reach 35% or greater. Arboreal pollen (AP)/non-arboreal pollen (NAP) ratios were calculated for each site and plotted against geographic distance along the transect. AP/NAP ratios of 7 or greater are found within pine-forest tundra and forest vegetation zones. Pinus stomates (dispersed stomatal guard cells) are absent from sites north of the coniferous treeline and all but two samples from the forested sites contain stomates. Stomate concentrations among the samples are highly variable and range from 10 to 458 per ml and positively correlate with the changing Pinus pollen values.

[Global climate change and carbon balance in forest ecosystems of boreal zones: imitating modeling as a forecast tool].

PubMed

Shanin, V N; Mikhaĭlov, A V; Bykhovets, S S; Komarov, A S

2010-01-01

The individually oriented system of the EFIMOD models simulating carbon and nitrogen flows in forest ecosystems has been used for forecasting the response of forest ecosystems to various forest exploitation regimes with climate change. As input data the forest management materials for the Manturovskii forestry of the Kostroma region were used. It has been shown that increase of mid-annual temperatures and rainfall influence the redistribution of carbon and nitrogen supply in organic form: supply increase of these elements in phytomass simultaneously with depletion of them in soil occurred. The most carbon and nitrogen accumulation in forest ecosystems occurs in the scenario without felling. In addition, in this scenario only the ecosystems of the modeling territory function as a carbon drain; in the other two scenarios (with selective and total felling) they function as a source of carbon. Climate changes greatly influence the decomposition rate of organic matter in soil, which leads to increased emission of carbonic acid. The second consequence of the increase in the destruction rate is nitrogen increase in the soil in a form available for plants that entails production increase of plantations.

[Spatial pattern of forest biomass and its influencing factors in the Great Xing'an Mountains, Heilongjiang Province, China].

PubMed

Wang, Xiao-Li; Chang, Yu; Chen, Hong-Wei; Hu, Yuan-Man; Jiao, Lin-Lin; Feng, Yu-Ting; Wu, Wen; Wu, Hai-Feng

2014-04-01

Based on field inventory data and vegetation index EVI (enhanced vegetation index), the spatial pattern of the forest biomass in the Great Xing'an Mountains, Heilongjiang Province was quantitatively analyzed. Using the spatial analysis and statistics tools in ArcGIS software, the impacts of climatic zone, elevation, slope, aspect and vegetation type on the spatial pattern of forest biomass were explored. The results showed that the forest biomass in the Great Xing'an Mountains was 350 Tg and spatially aggregated with great increasing potentials. Forest biomass density in the cold temperate humid zone (64.02 t x hm(-2)) was higher than that in the temperate humid zone (60.26 t x hm(-2)). The biomass density of each vegetation type was in the order of mixed coniferous forest (65.13 t x hm(-2)) > spruce-fir forest (63.92 t x hm(-2)) > Pinus pumila-Larix gmelinii forest (63.79 t x hm(-2)) > Pinus sylvestris var. mongolica forest (61.97 t x hm(-2)) > Larix gmelinii forest (61.40 t x hm(-2)) > deciduous broadleaf forest (58.96 t x hm(-2)). With the increasing elevation and slope, the forest biomass density first decreased and then increased. The forest biomass density in the shady slopes was greater than that in the sunny slopes. The spatial pattern of forest biomass in the Great Xing' an Mountains exhibited a heterogeneous pattern due to the variation of climatic zone, vegetation type and topographical factor. This spatial heterogeneity needs to be accounted when evaluating forest biomass at regional scales.

Relationship between forest clearing and biophysical factors in tropical environments: Implications for the design of a forest change monitoring approach. [Costa Rica

NASA Technical Reports Server (NTRS)

Sader, S. A.; Joyce, A. T.

1984-01-01

The relationship between forest clearing, biophysical factors (e.g, ecological zones, slope gradient, soils), and transportation network in Costa Rica was analyzed. The location of forested areas at four reference datas (1940, 1950, 1961, and 1977) as derived from aerial photography and LANDSAT MSS data was digitilized and entered into a geographically-referenced data base. Ecological zones as protrayed by the Holdridge Life Zone Ecology System, and the location of roads and railways were also digitized from maps of the entire country as input to the data base. Information on slope gradient and soils was digitized from maps of a 21,000 square kilometer area. The total area of forest cleared over four decades are related to biophysical factors was analyzed within the data base and deforestation rates and trends were tabulated. The relatiohship between forest clearing and ecological zone and the influence of topography, sils, and transportation network are presented and discussed.

Urban expansion in the forests of the Puget Sound region.

Treesearch

Colin D. MacLean; Charles L. Bolsinger

1997-01-01

As part of a 1979 forest resource inventory, over 9,000 points on aerial photographs were sorted into three development zones-primary forest, suburban, and urban. These same points were reexamined in 1989, and zone changes were noted. This report summarizes urban expansion into the primary forest lands of the Puget Sound region (Island, King, Kitsap, Pierce, San Juan,...

A postglacial coleopterous assemblage from Lockport Gulf, New York

NASA Astrophysics Data System (ADS)

Miller, Randy F.; Morgan, Alan V.

1982-03-01

The Lockport Gulf site near Lockport, New York, is a 1.9-m sequence of organic-rich marls having a basal date of approximately 10,920 yr B.P. Six bulk samples with a combined weight of 48 kg produced over 780 individual fossil insects representing five orders, as well as molluscs and abundant plant macrofossils. Coleoptera were represented by 24 families. Several major beetle groups (Carabidae, ground beetles; Hydrophilidae, water scavenger beetles; Elmidae, riffle beetles; Staphylinidae, rove beetles; and Scolytidae, bark beetles) indicate a riffle-and-pool stream, surrounded by marsh, with open riparian habitats and nearby trees. Two zones were recognized based on the Coleoptera assemblages. The Zone 1 fauna (ca. 10,920-9800 yr B.P.) was dominated by boreal forest taxa with abundant bark beetles indicating the presence of spruce trees. In Zone 2 (ca. 9700-9100 yr B.P.) the combination of species with a restricted modern distribution in the Great Lakes-St. Lawrence Forest region and pine and deciduous tree inhabitants suggests a change in vegetation by 9700 yr B.P. Thermal estimates from a faunal analysis indicate that the climatic conditions were stable across the spruce-pine transition, with the mean July temperature in the range of 16° to 18°C.

Multi-centennial ecosystem modelling in northeastern America at the species level

NASA Astrophysics Data System (ADS)

Steinkamp, J.; Biskupovic, A.; Rollinson, C.; Dawson, A.; Goring, S. J.; McLachlan, J. S.; Mladenoff, D. J.; Williams, J.; Hickler, T.

2016-12-01

Most dynamic global vegetation models (DGVM) are based on a small set of plant functional types (PFTs) to simulate biome distribution, vegetation dynamics, and carbon and nutrient cycles, which is of limited use for more regional studies and stakeholders. We tested a tree-species-based parameterization approach of the LPJ-GUESS DGVM in the northeastern USA, which previously has been successful in simulating the main potential natural vegetation zones in Europe. A transient model run was carried out from 850 A.D. to today, and the model results have been evaluated against pre-settlement vegetation maps and reconstructed vegetation from pollen within the PalEON project and hypothesized potential natural vegetation zones. We will analyze the simulation with respect to long term carbon cycling and the driving forces. Main reconstructed vegetation features were reproduced by the model, which implies that the general processes shaping the forested vegetation in parts of Europe and the northeastern USA are similar. However, so far the decrease in biomass towards the prairie in the west could not fully be captured by the model, which is currently analyzed with additional simulations. Moisture and fire are the important driver at the prairie forest transition zone, which we need to better constrain for this model domain.

Applying a dryland degradation framework for rangelands: the case of Mongolia.

PubMed

Jamsranjav, C; Reid, R S; Fernández-Giménez, M E; Tsevlee, A; Yadamsuren, B; Heiner, M

2018-04-01

Livestock-caused rangeland degradation remains a major policy concern globally and the subject of widespread scientific study. This concern persists in part because it is difficult to isolate the effects of livestock from climate and other factors that influence ecosystem conditions. Further, degradation studies seldom use multiple plant and soil indicators linked to a clear definition of and ecologically grounded framework for degradation assessment that distinguishes different levels of degradation. Here, we integrate two globally applicable rangeland degradation frameworks and apply them to a broad-scale empirical data set for the country of Mongolia. We compare our assessment results with two other recent national rangeland degradation assessments in Mongolia to gauge consistency of findings across assessments and evaluate the utility of our framework. We measured livestock-use impacts across Mongolia's major ecological zones: mountain and forest steppe, eastern steppe, steppe, and desert steppe. At 143 sites in 36 counties, we measured livestock-use and degradation indicators at increasing distances from livestock corrals in winter-grazed pastures. At each site, we measured multiple indicators linked to our degradation framework, including plant cover, standing biomass, palatability, species richness, forage quality, vegetation gaps, and soil surface characteristics. Livestock use had no effect on soils, plant species richness, or standing crop biomass in any ecological zone, but subtly affected plant cover and palatable plant abundance. Livestock effects were strongest in the steppe zone, moderate in the desert steppe, and limited in the mountain/forest and eastern steppes. Our results aligned closely with those of two other recent country-wide assessments, suggesting that our framework may have widespread application. All three assessments found that very severe and irreversible degradation is rare in Mongolia (1-18% of land area), with most rangelands slightly (33-53%) or moderately (25-40%) degraded. We conclude that very severe livestock-induced rangeland degradation is overstated in Mongolia. However, targeted rangeland restoration coupled with monitoring, adaptive management and stronger rangeland governance are needed to prevent further degradation where heavy grazing could cause irreversible change. Given the broad applicability of our degradation framework for Mongolia, we suggest it be tested for application in other temperate grasslands throughout Central Asia and North America. © 2018 The Authors Ecological Applications published by Wiley Periodicals, Inc. on behalf of Ecological Society of America.

Development of an establishment scheme for a DGVM

NASA Astrophysics Data System (ADS)

Song, Xiang; Zeng, Xiaodong; Zhu, Jiawen; Shao, Pu

2016-07-01

Environmental changes are expected to shift the distribution and abundance of vegetation by determining seedling establishment and success. However, most current ecosystem models only focus on the impacts of abiotic factors on biogeophysics (e.g., global distribution, etc.), ignoring their roles in the population dynamics (e.g., seedling establishment rate, mortality rate, etc.) of ecological communities. Such neglect may lead to biases in ecosystem population dynamics (such as changes in population density for woody species in forest ecosystems) and characteristics. In the present study, a new establishment scheme for introducing soil water as a function rather than a threshold was developed and validated, using version 1.0 of the IAP-DGVM as a test bed. The results showed that soil water in the establishment scheme had a remarkable influence on forest transition zones. Compared with the original scheme, the new scheme significantly improved simulations of tree population density, especially in the peripheral areas of forests and transition zones. Consequently, biases in forest fractional coverage were reduced in approximately 78.8% of the global grid cells. The global simulated areas of tree, shrub, grass and bare soil performed better, where the relative biases were reduced from 34.3% to 4.8%, from 27.6% to 13.1%, from 55.2% to 9.2%, and from 37.6% to 3.6%, respectively. Furthermore, the new scheme had more reasonable dependencies of plant functional types (PFTs) on mean annual precipitation, and described the correct dominant PFTs in the tropical rainforest peripheral areas of the Amazon and central Africa.

Evaluating the suitability of planted forests for African forest monkeys: a case study from Kakamega forest, Kenya.

PubMed

Fashing, Peter J; Nguyen, Nga; Luteshi, Patrick; Opondo, Winstone; Cash, Julie F; Cords, Marina

2012-01-01

As natural forest cover declines, planted forests have come to occupy an increasing percentage of the earth's surface, yet we know little about their suitability as alternative habitat for wildlife. Although some primate species use planted forests, few studies have compared primate populations in natural and nearby planted forests. From March 2006 to July 2010, we conducted line transect surveys and assessed group sizes and compositions in natural and nearby 60-70 year old mixed indigenous planted forest to determine the densities of diurnal primate species (Colobus guereza, Cercopithecus mitis, C. ascanius) in these two forest types at Isecheno, Kakamega Forest, Kenya. Line transect data were analyzed using the Encounter Rate, Whitesides, and Distance sampling methods, which all provided broadly consistent results. We found that all three diurnal primate species occupy both natural and planted forest at Isecheno. However, group densities of the two Cercopithecus species were 42-46% lower in planted than in natural forest. Colobus guereza achieved comparable group densities in the two forest types, although the species is found in smaller groups, and thus at lower (35%) individual density, in planted than in natural forest. Following a logging episode in the planted forest mid-way through our study, Cercopithecus ascanius group densities fell by 60% while C. mitis and Colobus guereza group densities remained stable over the next two years. Overall, our results suggest that while primate species vary in their response to habitat disturbance, planted forest has the potential to contribute to the conservation of some African monkey species. Even for the relatively flexible taxa in our study, however, 60-70 year old mixed indigenous planted forest failed to support densities comparable to those in nearby natural forest. From the perspective of Kakamega's primates, planted forests may supplement natural forest, but are not an adequate replacement for it. © 2011 Wiley Periodicals, Inc.

Radiation ecology issues associated with murine rodents and shrews in the Chernobyl exclusion zone.

PubMed

Gaschak, Sergey P; Maklyuk, Yulia A; Maksimenko, Andrey M; Bondarkov, Mikhail D; Jannik, G Timothy; Farfán, Eduardo B

2011-10-01

This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals and reviews interspecies differences in radionuclide accumulations and factors affecting the radionuclide accumulations. It is shown that bioavailability of radionuclides in the "soil-to-plant" chain and a trophic specialization of animals play key roles in determining their actual contamination levels. The total absorbed dose rates in small mammals significantly reduced during the years following the Chernobyl Nuclear Power Plant accident. In 1986, the absorbed dose rate reached 1.3-6.0 Gy h(-1) in the central areas of the Chernobyl Exclusion Zone (the "Red Forest"). In 1988 and 1990, the total absorbed dose rates were 1.3 and 0.42 Gy h(-1), respectively. In 1995, 2000, and 2005, according to the present study, the total absorbed dose rates rarely exceeded 0.00023, 0.00018, and 0.00015 Gy h(-1), respectively. Contributions of individual radiation sources into the total absorbed dose are described.

Mapping Forest Fire Susceptibility in Temperate Mountain Areas with Expert Knowledge. A Case Study from Iezer Mountains, Romanian Carpathians

NASA Astrophysics Data System (ADS)

Mihai, Bogdan; Savulescu, Ionut

2014-05-01

Forest fires in Romanian Carpathians became a frequent phenomenon during the last decade, although local climate and other environmental features did not create typical conditions. From 2004, forest fires affect in Romania more than 100 hectares/year of different forest types (deciduous and coniferous). Their magnitude and frequency are not known, since a historical forest fire inventory does not exist (only press papers and local witness for some selected events). Forest fires features the summer dry periods but there are dry autumns and early winter periods with events of different magnitudes. The application we propose is based on an empirical modeling of forest fire susceptibility in a typical mountain area from the Southern Carpathians, the Iezer Mountains (2462 m). The study area features almost all the altitudinal vegetation zones of the European temperate mountains, from the beech zone, to the coniferous zone, the subalpine and the alpine zones (Mihai et al., 2007). The analysis combines GIS and remote sensing models (Chuvieco et al., 2012), starting from the ideas that forest fires are featured by the ignition zones and then by the fire propagation zones. The first data layer (ignition zones) is the result of the crossing between the ignition factors: lightning - points of multitemporal occurence and anthropogenic activities (grazing, tourism and traffic) and the ignition zones (forest fuel zonation - forest stands, soil cover and topoclimatic factor zonation). This data is modelled from different sources: the MODIS imagery fire product (Hantson et al., 2012), detailed topographic maps, multitemporal orthophotos at 0.5 m resolution, Landsat multispectral imagery, forestry cadastre maps, detailed soil maps, meteorological data (the WorldClim digital database) as well as the field survey (mapping using GPS and local observation). The second data layer (fire propagation zones) is the result of the crossing between the forest fuel zonation, obtained with the help of forestry data, the wind regime data and the topographic features of the mountain area (elevation, slope declivity, slope aspect). The analysis also consider the insolation degree of mountain slopes, that creates favourable conditions for fire propagation between different canopies. These data layers are integrated within a simple GIS analysis in order to intersect the ignition zones with the fire propagation zones in order to obtain the potential areas to be affected by fire. The digital map show three levels of forest fire susceptibility, differenced on the basis of expert knowledge. The map can be validated from the statistical point of view with the polygons of the forest fire affected areas mapped from Landsat TM, ETM+ and OLI satellite imagery. The mapping results could be integrated within the forest management strategies and especially within the forest cadastre and development maps (updated every ten years). The result can confirm that the data gap in terms of forest fire events can be filled with expert knowledge. References Chuvieco, E, Aguado, I., Jurdao, S., Pettinari, M., Yebra, M., Salas, J., Hantson, S., de la Riva, J., Ibarra, P., Rodrigues, M., Echeverria, M., Azqueta, D., Roman, M., Bastarrika, A., Martinez, S., Recondo, C., Zapico, E., Martinez-Vega F.J. (2012) Integrating geospatial information into fire risk assessment, International Journal of Wildland Fire, 2,2, 69-86. Hantson, S., Padilla, M., Corti., D, Chuvieco, E. (2013) Strenghts and weaknesses of MODIS hotspots to characterize Global fire occurence, Remote Sensing of Environment, 131, 1, 152-159. Mihai, B., Savulescu, I.,Sandric, I. (2007) Change detection analysis (1986/2002) for the alpine, subalpine and forest landscape in Iezer Mountains (Southern Carpathians, Romania), Mountain Research and Development, 27, 250-258.

Expanding the scale of forest management: allocating timber harvests in time and space

Treesearch

Eric J. Gustafson

1996-01-01

This study examined the effect of clustering timber harvest zones and of changing the land use categories of zones (dynamic zoning) over varying temporal and spatial scales. Focusing on the Hoosier National Forest (HNF) in Indiana, USA as a study area, I used a timber harvest allocation model to simulate four management alternatives. In the static zoning alternative,...

Landscape and zonal features of the formation of producing economy in Russia

NASA Astrophysics Data System (ADS)

Nizovtsev, Vyacheslav; Natalia, Erman

2016-04-01

Based on analysis of the extensive source base, including complex landscape, component, paleogeographic and archeological published and scientific materials as well as the connected analysis of published paleogeographical, paleolandscape and historical and geographic maps of the territory of Russia landscape and zonal features of the transition from appropriating economy to producing economy were determined. All the specifics of historical changes in the landscape use of the vast areas of Russia is caused by the variety of its landscape zones and the specifics of their constituent landscapes. Human economic activities as a factor of differentiation and development of landscapes became apparent almost in all landscape zones together with the emergence of the producing type of economy from the Aeneolithic-Bronze Age (Atlantic period) in the southern steppe regions (in the northern areas of the main centers of the producing economy) and from the Bronze Age in the forest areas. The emergence of the producing economy in the forest-steppe and steppe landscape zones on the territory of Russia is dated IV (Aeneolithic) - III (Early Bronze Age) millennium BC. It is from this period that on the European part of Russia and in Siberia the so-called Neolithic revolution begins. The use of copper and bronze axes helped to develop new areas for planting crops in the forest-steppe zone. In the forest-steppe zone swidden and lea tillage cultivation develops. In the steppe and forest-steppe Eurasia depending on the local landscape conditions two ways of producing economy with a predominance of cattle-breeding developed: nomadic cattle breeding and house cattle breeding with a significant influence of agriculture in the economy and long-term settlements. The steppe areas were completely dominated by the mobile nomadic herding, breeding cattle and small cattle. Along with the valley landscapes the interfluvial landscapes were also actively explored. Almost in all the steppe areas there was a cattle breeding economic and cultural type of producing economy with a simplified system of natural and anthropogenic and anthropogenic landscapes involving a maximum of 4-5 natural and economic systems. In the forest-steppe zone a significant part of the population was settled in the valley landscapes. The basis of the economy was pastoral and house cattle breeding with a predominance of beef cattle and pigs and hoe-mattock agriculture, which was only possible in the floodplain landscape complexes. In the areas of permanent settlements long grazing in one place led to the complete destruction of vegetation. The forced reduction of the agricultural land areas led to significant ecologic crisis. In the forest zone, along with hunters, fishermen and gatherers there appear the first tribes, who already engaged in the forest cattle breeding. First, they raised pigs and then small and beef cattle, while hunting and fishing were of subordinate nature. Pastures were situated mainly in floodplains and lakeside lowlands which had more open spaces. It is the extensive economy of that time that can be associated with the deforestation of flood plains of rivers and lakes and the emergence of meadows. There arises a natural-economic system with floodplain cattle-breeding (agricultural geo-systems of pasture type with floodplain meadows and woodlands), which existed for a long time. In all landscape zones the character of the relationship between men and the landscape was determined by the nature of producing activity, as well as natural features of "accommodating" landscape. The formation of nature use systems and settlement patterns strictly depend on the local landscape structure. In all earlier historical periods in similar landscape (zonal) conditions the settlers had the same type of economy, thus forming the same types of natural and economic systems and similar anthropogenically transformed landscapes. The dramatic change in the nature use occurs with the settlement in the forest and steppe zones of the Iron Age tribes, which had a complex cattle-breeding and agricultural economy. Irreversible changes captured many of the components, including soils and lithogenic basis, of the landscapes. In the morphological structure of the landscapes there appear new permanent stable elements of anthropogenic origin: residential and arable, many of which have survived to this day. The work is performed under the project of Russian Foundation for Basic Research № 14-05-00618

Uav-Based Detection of Unknown Radioactive Biomass Deposits in Chernobyl's Exclusion Zone

NASA Astrophysics Data System (ADS)

Briechle, S.; Sizov, A.; Tretyak, O.; Antropov, V.; Molitor, N.; Krzystek, P.

2018-05-01

Shortly after the explosion of the Chernobyl nuclear power plant (ChNPP) in 1986, radioactive fall-out and contaminated trees (socalled Red Forest) were buried in the Chernobyl Exclusion Zone (ChEZ). These days, exact locations of the buried contaminated material are needed. Moreover, 3D vegetation maps are necessary to simulate the impact of tornados and forest fire. After 30 years, some of the so-called trenches and clamps are visible. However, some of them are overgrown and have slightly settled in the centimeter and decimeter range. This paper presents a pipeline that comprises 3D vegetation mapping and machine learning methods to precisely map trenches and clamps from remote sensing data. The dataset for our experiments consists of UAV-based LiDAR data, multi-spectral data, and aerial gamma-spectrometry data. Depending on the study areas overall accuracies ranging from 95.6 % to 99.0 % were reached for the classification of radioactive deposits. Our first results demonstrate an accurate and reliable UAV-based detection of unknown radioactive biomass deposits in the ChEZ.

Variation in forest biomass change highlights regional differences in forest succession in the Pacific Northwest, USA.

NASA Astrophysics Data System (ADS)

Bell, D. M.; Gray, A. N.

2014-12-01

Forest successional theory describes the changes in forest biomass and community composition from forest establishment to climax communities, but the drivers of succession are still widely debated. For example, successional models have related biomass and community change to stand age, species rarity within the community, small-scale disturbance, or the ability of species to survive under low resource conditions. The degree to which these drivers might vary regionally limits our ability to model and predict ecosystem change. Our objective was to assess whether forest successional theory explains observed changes in species biomass and community composition across forests of the U. S. Pacific Northwest. Using remeasurements of 9,700 Current Vegetation Survey (CVS) National Forest inventory plots primarily in Oregon and Washington, we quantified the effects of forest stand age, community composition, disturbance, and moisture (i.e., topography and climate) on changes in species-specific proportional live biomass (ΔB) and species dominance (ΔD). We focused on differences in forest successional patterns in two vegetation zones: the Tsuga heterophylla (TSHE) zone, found at low elevations on the wet, west side of the Cascade Mountains; and the Abies concolor (ABCO) zone, found at mid-elevations on the dry, east side of the Cascade Mountains. Preliminary results indicate that the regional differences in tree species biomass change and dominance appear to be related to responses to climate and disturbance. Strong positive effects of cover change on ΔB were observed in the drier ABCO zone, but not the wetter TSHE zone. ΔB and ΔD were more often sensitive to precipitation and topographic position in the ABCO zone. In both regions, we found that ΔB was strongly negatively related to species biomass and stand age while ΔD was strongly negatively related to relative density, highlighting the importance of both age and community in shaping succession. Given that the importance of different forest successional processes in shaping ecosystem change varied regionally, this work provides valuable insights into potential risks of changing climate and disturbance regimes to species persistence and ecosystem stability across forests of the U.S. Pacific Northwest.

Trend of Soil Erosion Processes within the Southern Half of the Russian Plain for the Last Decades

NASA Astrophysics Data System (ADS)

Golosov, V. N.; Yermolaev, O. P.; Safina, G. R.; Maltsev, K. A.; Gusarov, A. V.; Rysin, I. I.

2018-01-01

Complex approach is applied for assessment of recent trends of sheet, rill and gully erosion in different landscape zones of study area. Investigation is undertaken in 6 selected sectors (area of each transect is about 6-10 thousand km2), uniformly distributed over the area of the Russian Plain. Changes of the different factors, including some meteorological and hydrological parameters, land use change, USLE C-factor, were determined for the period 1980-2015. A set of field methods was used for quantification of sediment redistribution rates for the key small catchments. It was found that erosion rate decreased in forest and forest-steppe zone. Gully density decreases considerably in all landscape zones. The reduction of surface runoff from cultivated slope during snow-melting is the main reason of decreasing of sheet, rill and gully erosion rates in the forest, forest steppe and the north of steppe landscape zones. Increasing the proportion of perennial grasses in crop-rotation is the other factor of serious reduction of erosion processes in the forest zone.

36 CFR 13.430 - Determination of resident zones.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Determination of resident zones. 13.430 Section 13.430 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF.... (a) A resident zone shall include— (1) The area within a national park or monument; and (2) The...

36 CFR 28.15 - Approval of local zoning ordinances.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Approval of local zoning ordinances. 28.15 Section 28.15 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR FIRE ISLAND NATIONAL SEASHORE: ZONING STANDARDS Federal Standards and Approval of Local Ordinances...

36 CFR 28.15 - Approval of local zoning ordinances.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Approval of local zoning ordinances. 28.15 Section 28.15 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR FIRE ISLAND NATIONAL SEASHORE: ZONING STANDARDS Federal Standards and Approval of Local Ordinances...

Diversity of Medicinal Plants among Different Forest-use Types of the Pakistani Himalaya.

PubMed

Adnan, Muhammad; Hölscher, Dirk

2012-12-01

Diversity of Medicinal Plants among Different Forest-use Types of the Pakistani Himalaya Medicinal plants collected in Himalayan forests play a vital role in the livelihoods of regional rural societies and are also increasingly recognized at the international level. However, these forests are being heavily transformed by logging. Here we ask how forest transformation influences the diversity and composition of medicinal plants in northwestern Pakistan, where we studied old-growth forests, forests degraded by logging, and regrowth forests. First, an approximate map indicating these forest types was established and then 15 study plots per forest type were randomly selected. We found a total of 59 medicinal plant species consisting of herbs and ferns, most of which occurred in the old-growth forest. Species number was lowest in forest degraded by logging and intermediate in regrowth forest. The most valuable economic species, including six Himalayan endemics, occurred almost exclusively in old-growth forest. Species composition and abundance of forest degraded by logging differed markedly from that of old-growth forest, while regrowth forest was more similar to old-growth forest. The density of medicinal plants positively correlated with tree canopy cover in old-growth forest and negatively in degraded forest, which indicates that species adapted to open conditions dominate in logged forest. Thus, old-growth forests are important as refuge for vulnerable endemics. Forest degraded by logging has the lowest diversity of relatively common medicinal plants. Forest regrowth may foster the reappearance of certain medicinal species valuable to local livelihoods and as such promote acceptance of forest expansion and medicinal plants conservation in the region. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12231-012-9213-4) contains supplementary material, which is available to authorized users.

Space images processing methodology for assessment of atmosphere pollution impact on forest-swamp territories

NASA Astrophysics Data System (ADS)

Polichtchouk, Yuri; Tokareva, Olga; Bulgakova, Irina V.

2003-03-01

Methodical problems of space images processing for assessment of atmosphere pollution impact on forest ecosystems using geoinformation systems are developed. An approach to quantitative assessment of atmosphere pollution impact on forest ecosystems is based on calculating relative squares of forest landscapes which are inside atmosphere pollution zones. Landscape structure of forested territories in the southern part of Western Siberia are determined on the basis of procession of middle resolution space images from spaceborn Resource-O. Particularities of atmosphere pollution zones modeling caused by gas burning in torches on territories of oil fields are considered. Pollution zones were revealed by modeling of contaminants dispersal in atmosphere with standard models. Polluted landscapes squares are calculated depending on atmosphere pollution level.

Remote Sensing of Forest Cover in Boreal Zones of the Earth

NASA Astrophysics Data System (ADS)

Sedykh, V. N.

2011-12-01

Ecological tension resulting from human activities generates a need for joint efforts of countries in the boreal zone aimed at sustainable forest development, including: conservation of forests binding carbon and ensuring stability of the atmosphere gas composition; preservation of purity and water content of forest areas as conditions ensuring sustainability of the historically formed structure of forest landscapes; and preservation of all flora and fauna species composition diversity as a condition for sustainable existence and functioning of forest ecosystems. We have to address these problems urgently due to climate warming which can interact with the forest cover. In particular, in the forest zone of Siberia, the climate aridization will inevitably result in periodic drying of shallow bogs and upland forests with thick forest litter. This will bring fires of unprecedented intensity which will lead to catastrophic atmospheric pollution. In this connection, the above problems can be solved only by the united efforts of boreal-zone countries, through establishing a uniform system for remote sensing of forests aimed at obtaining and periodic update of comprehensive information for rational decision-making in prevention of adverse human effect on the forest. A need to join efforts in this field of natural resource management is determined by disparate data which were created expressly for economic accounting units used mainly for the solution of economic timber resource problems. However, ecological tasks outlined above can be solved appropriately only by using uniform technologies that are registered within natural territorial complexes (landscapes) established throughout the entire boreal zone. Knowledge of forest state within natural territorial entities having specific physiographic conditions, with account for current and future anthropogenic load, allow one to define evidence-based forest growth potential at these landscapes to ensure development of historically formed ecological properties of the forest. Constantly updated information will permit the regulation of human pressure on forests to ensure that there is no reduction in their role in the biosphere processes of carbon accumulation and release. Satellite monitoring within identified landscape requires initial quantitative information about forest, about other biotic components of landscapes, and about their abiotic environment determined through both ground-based measurements and remote sensing. Thus, a kind of passport should be kept for each landscape as a starting point for subsequent updating of remote sensing monitoring of forests and their habitats and the assessment of their changes. Implementation of such monitoring across the entire boreal zone of the Earth is possible on the basis of geographical and genetic typology of forest and phyto-geomorphological method of aerospace image interpretation. Both approaches are based on the use of relationships between topography and vegetation, and were successfully applied by the author to aerospace monitoring of the forest cover of West Siberian Plain.

The relationship between Anopheles gambiae density and rice cultivation in the savannah zone and forest zone of Côte d'Ivoire.

PubMed

Briët, Olivier J T; Dossou-Yovo, Joel; Akodo, Elena; van de Giesen, Nick; Teuscher, Thomas M

2003-05-01

In 13 villages in the savannah zone and 21 villages in the forest zone of Côte d'Ivoire, the biting density of the principal malaria vector, Anopheles gambiae, was studied as a function of rice cultivation in the inland valleys in a 2-km radius around each village. In the savannah villages, during the main season cropping period, surface water on rice-cultivated and to a lesser extent on uncultivated inland valleys seems to contribute strongly to the A. gambiae population density. For the off-season cropping period (which starts after the first light rains in the savannah zone), correlations were weaker. Breeding sites other than in inland valleys may play an important role in the savannah zone. In the forest zone, however, the A. gambiae population density was strongly correlated with the surface water availability (SWA) in the rice-cultivated inland valleys, whereas the correlation with the SWA in other (uncultivated) inland valleys was weak. The requirement of sunlit breeding sites for A. gambiae might explain this difference between zones. In the forest zone, only inland valleys cleared for rice cultivation meet this requirement, whereas all other inland valleys are covered with dense vegetation. In the savannah zone, however, most undergrowth is burnt during the dry season, which permits sunlight to reach puddles resulting from the first rains.

Are mangroves in the tropical Atlantic ripe for invasion? Exotic mangrove trees in the forests of South Florida

USGS Publications Warehouse

Fourqurean, James W.; Smith, Thomas J.; Possley, Jennifer; Collins, Timothy M.; Lee, David; Namoff, Sandra

2010-01-01

Two species of mangrove trees of Indo-Pacific origin have naturalized in tropical Atlantic mangrove forests in South Florida after they were planted and nurtured in botanic gardens. Two Bruguiera gymnorrhiza trees that were planted in the intertidal zone in 1940 have given rise to a population of at least 86 trees growing interspersed with native mangrove species Rhizophora mangle, Avicennia germinans and Laguncularia racemosa along 100 m of shoreline; the population is expanding at a rate of 5.6% year−1. Molecular genetic analyses confirm very low genetic diversity, as expected from a population founded by two individuals. The maximum number of alleles at any locus was three, and we measured reduced heterozygosity compared to native-range populations. Lumnitzera racemosa was introduced multiple times during the 1960s and 1970s, it has spread rapidly into a forest composed of native R. mangle, A. germinans, Laguncularia racemosa and Conocarpus erectus and now occupies 60,500 m2 of mangrove forest with stem densities of 24,735 ha−1. We estimate the population growth rate of Lumnitzera racemosa to be between 17 and 23% year−1. Populations of both species of naturalized mangroves are dominated by young individuals. Given the long life and water-dispersed nature of propagules of the two exotic species, it is likely that they have spread beyond our survey area. We argue that the species-depauperate nature of tropical Atlantic mangrove forests and close taxonomic relatives in the more species-rich Indo-Pacific region result in the susceptibility of tropical Atlantic mangrove forests to invasion by Indo-Pacific mangrove species.

Songbird use of floodplain and upland forests along the Upper Mississippi River corridor during spring migration

USGS Publications Warehouse

Kirsch, Eileen M.; Heglund, Patricia J.; Gray, Brian R.; Mckann, Patrick

2013-01-01

The Upper Mississippi River is thought to provide important stopover habitat for migrating landbirds because of its north-south orientation and floodplain forests. The river flows through the Driftless Area of southwestern Wisconsin and southeastern Minnesota where forests are plentiful, yet forests of the floodplain and Driftless Area uplands differ greatly in landscape setting, tree species composition, and topography. We compared landbird assemblages in these upland and floodplain forests over three springs, 2005–2007, using line-transect surveys at randomly selected areas in and within 16 km of the floodplain. We found more species of both transient and locally breeding migrants per survey in floodplain than in upland forest. Detections of transient neotropical migrants did not differ statistically by habitat. Detections of locally breeding neotropical and temperate-zone migrants and transient temperate-zone migrants were greater in floodplain than in upland forest. Between floodplain and upland forest, assemblages of locally breeding species, including neotropical and temperate-zone migrants (of which some individuals were in transit), differed substantially, but assemblages of transients (including both neotropical and temperate-zone migrants) did not differ as much. Only two species of transient migrants had clear affinities for floodplain forest, and none had an affinity for upland forest, whereas most locally breeding migrants had an affinity for either upland or floodplain forest. Within each spring, however, detections of transient neotropical migrants shifted from being greater in floodplain to greater in upland forests. This intraseasonal shift may be related to the phenology of certain tree species.

Exotic Plants are Invading Southeastern Forests

Treesearch

James H. Miller

1997-01-01

Millions of acres of forest land in the Southeast are being occupied increasingly by non-indigenous harmful plants--exotic invasive plants. They are called exotic invasive plants, because these plants from other continents invade areas in the U.S. faster and more completely than most native species. Invasive exotic plants impede forest productivity, hinder forest-use...

Predicting vegetation type through physiological and environmental interactions with leaf traits: evergreen and deciduous forests in an earth system modeling framework.

PubMed

Weng, Ensheng; Farrior, Caroline E; Dybzinski, Ray; Pacala, Stephen W

2017-06-01

Earth system models are incorporating plant trait diversity into their land components to better predict vegetation dynamics in a changing climate. However, extant plant trait distributions will not allow extrapolations to novel community assemblages in future climates, which will require a mechanistic understanding of the trade-offs that determine trait diversity. In this study, we show how physiological trade-offs involving leaf mass per unit area (LMA), leaf lifespan, leaf nitrogen, and leaf respiration may explain the distribution patterns of evergreen and deciduous trees in the temperate and boreal zones based on (1) an evolutionary analysis of a simple mathematical model and (2) simulation experiments of an individual-based dynamic vegetation model (i.e., LM3-PPA). The evolutionary analysis shows that these leaf traits set up a trade-off between carbon- and nitrogen-use efficiency at the scale of individual trees and therefore determine competitively dominant leaf strategies. As soil nitrogen availability increases, the dominant leaf strategy switches from one that is high in nitrogen-use efficiency to one that is high in carbon-use efficiency or, equivalently, from high-LMA/long-lived leaves (i.e., evergreen) to low-LMA/short-lived leaves (i.e., deciduous). In a region of intermediate soil nitrogen availability, the dominant leaf strategy may be either deciduous or evergreen depending on the initial conditions of plant trait abundance (i.e., founder controlled) due to feedbacks of leaf traits on soil nitrogen mineralization through litter quality. Simulated successional patterns by LM3-PPA from the leaf physiological trade-offs are consistent with observed successional dynamics of evergreen and deciduous forests at three sites spanning the temperate to boreal zones. © 2016 John Wiley & Sons Ltd.

The warming effect of the flare of natural gas on soil biological activity

NASA Astrophysics Data System (ADS)

Yevdokimov, Ilya; Yusupov, Irek; Shavnin, Sergey

2017-04-01

Simulation of global warming is one of the key issues of international efforts to study climatic changes. A number of manipulation experiments with soil warming have been established throughout the world in the last decades. We used warming with natural gas flare near the pine forest as a kind of manipulation experiment to assess the synergistic effect of drying and warming on plant-soil-microbial interactions. The experimental area is situated in a pine forest subzone of the forest zone of the Western Siberia near Pokachi, Yugra (61o73'N, 75o49'E). The experimental plots were established in a young Scotch pine forest on sandy podzolic soil at three distances of 70, 90 and 130 m from the flare of natural gas, with trees exposed to strong (S) moderate (M), and weak (W) impact, respectively. Increase of soil temperature in summer time were moderate: on average 0.7oC and 1.3oC for the plots M and S, respectively, compared to the plot W. The plot S demonstrated increase in CO2 efflux from the soil surface, mainly due to intensifying plant root respiration, by 18% compared to the plot W as well as increase in SOM content by 31%, with intensive accumulation of recalcitrant humus. By contrast, microbial biomass, labile SOM pool and basal respiration were higher in soil with weak flaring impact by 74%, 33% and 24%, respectively. Thus, three trends in plant-soil-microbe system exposed to warming and drying were revealed: i) SOM accumulation, ii) suppression of microbial activity, and iii) stimulation of root respiration. The research was supported by the Russian Science Foundation and Russian Foundation for Basic Researches.

Palaeoecological data as a tool to predict possible future vegetation changes in the boreal forest zone of European Russia: a case study from the Central Forest Biosphere Reserve

NASA Astrophysics Data System (ADS)

Novenko, E. Yu; Tsyganov, A. N.; Olchev, A. V.

2018-01-01

New multi-proxy records (pollen, testate amoebae, and charcoal) were applied to reconstruct the vegetation dynamics in the boreal forest area of the southern part of Valdai Hills (the Central Forest Biosphere Reserve) during the Holocene. The reconstructions of the mean annual temperature and precipitation, the climate moisture index (CMI), peatland surface moisture, and fire activity have shown that climate change has a significant impact on the boreal forests of European Russia. Temperature growth and decreased moistening during the warmest phases of the Holocene Thermal Maximum in 7.0-6.2 ka BP and 6.0-5.5 ka BP and in the relatively warm phase in 3.4-2.5 ka BP led to structural changes in plant communities, specifically an increase in the abundance of broadleaf tree species in forest stands and the suppression of Picea. The frequency of forest fires was higher in that period, and it resulted in the replacement of spruce forests by secondary stands with Betula and Pinus. Despite significant changes in the climatic parameters projected for the 21st century using even the optimistic RCP2.6 scenario, the time lag between climate changes and vegetation responses makes any catastrophic vegetation disturbances (due to natural reasons) in the area in the 21st century unlikely.

Assessing the opportunity cost of implementing streamside management zone guidelines in eastern hardwood forests

Treesearch

Chris B. LeDoux

2006-01-01

Forest landowners, managers, loggers, land-use planners, and other decision/policy makers need to understand the opportunity cost associated with different levels of allowable management and required/voluntary protection in streamside management zones (SMZs). Four different logging technologies, two mature hardwood stands, three levels of streamside zone protection,...

The Use of a Geographic Information System and Remote Sensing Technology for Monitoring Land Use and Soil Carbon Change in the Subtropical Dry Forest Life Zone of Puerto Rico

NASA Technical Reports Server (NTRS)

Velez-Rodriguez, Linda L. (Principal Investigator)

1996-01-01

Aerial photography, one of the first form of remote sensing technology, has long been an invaluable means to monitor activities and conditions at the Earth's surface. Geographic Information Systems or GIS is the use of computers in showing and manipulating spatial data. This report will present the use of geographic information systems and remote sensing technology for monitoring land use and soil carbon change in the subtropical dry forest life zone of Puerto Rico. This research included the south of Puerto Rico that belongs to the subtropical dry forest life zone. The Guanica Commonwealth Forest Biosphere Reserve and the Jobos Bay National Estuarine Research Reserve are studied in detail, because of their location in the subtropical dry forest life zone. Aerial photography, digital multispectral imagery, soil samples, soil survey maps, field inspections, and differential global positioning system (DGPS) observations were used.

Rare Plants of the Redwood Forest and Forest Management Effects

Treesearch

Teresa Sholars; Clare Golec

2007-01-01

Coast redwood forests are predominantly a timber managed habitat type, subjected to repeated disturbances and short rotation periods. What does this repeated disturbance mean for rare plants associated with the redwood forests? Rare plant persistence through forest management activities is influenced by many factors. Persistence of rare plants in a managed landscape is...

Deforestation and Forest Fires in Roraima and Their Relationship with Phytoclimatic Regions in the Northern Brazilian Amazon

NASA Astrophysics Data System (ADS)

Barni, Paulo Eduardo; Pereira, Vaneza Barreto; Manzi, Antonio Ocimar; Barbosa, Reinaldo Imbrozio

2015-05-01

Deforestation and forest fires in the Brazilian Amazon are a regional-scale anthropogenic process related to biomass burning, which has a direct impact on global warming due to greenhouse gas emissions. Containment of this process requires characterizing its spatial distribution and that of the environmental factors related to its occurrence. The aim of this study is to investigate the spatial and temporal distribution of deforested areas and forest fires in the State of Roraima from 2000 to 2010. We mapped deforested areas and forest fires using Landsat images and associated their occurrence with two phytoclimatic zones: zone with savanna influence (ZIS), and zone without savanna influence (ZOS). Total deforested area during the interval was estimated at 3.06 × 103 km2 (ZIS = 55 %; ZOS = 45 %) while total area affected by forest fires was estimated at 3.02 × 103 km2 (ZIS = 97.7 %; ZOS = 2.3 %). Magnitude of deforestation in Roraima was not related to the phytoclimatic zones, but small deforested areas (≤17.9 ha) predominated in ZOS while larger deforestation classes (>17.9 ha) predominated in ZIS, which is an area with a longer history of human activities. The largest occurrence of forest fires was observed in the ZIS in years with El Niño events. Our analysis indicates that the areas most affected by forest fires in Roraima during 2000-2010 were associated with strong climatic events and the occurrence these fires was amplified in ZIS, a sensitive phytoclimatic zone with a higher risk of anthropogenic fires given its drier climate and open forest structure.

Acceleration and novelty: community restoration speeds recovery and transforms species composition in Andean cloud forest.

PubMed

Wilson, Sarah Jane; Rhemtulla, Jeanine M

2016-01-01

Community-based tropical forest restoration projects, often promoted as a win-win solution for local communities and the environment, have increased dramatically in number in the past decade. Many such projects are underway in Andean cloud forests, which, given their extremely high biodiversity and history of extensive clearing, are understudied. This study investigates the efficacy of community-based tree-planting projects to accelerate cloud forest recovery, as compared to unassisted natural regeneration. This study takes place in northwest Andean Ecuador, where the majority of the original, highly diverse cloud forests have been cleared, in five communities that initiated tree-planting projects to restore forests in 2003. In 2011, we identified tree species along transects in planted forests (n = 5), naturally regenerating forests (n = 5), and primary forests (n = 5). We also surveyed 120 households about their restoration methods, tree preferences, and forest uses. We found that tree diversity was higher in planted than in unplanted secondary forest, but both were less diverse than primary forests. Ordination analysis showed that all three forests had distinct species compositions, although planted forests shared more species with primary forests than did unplanted forests. Planted forests also contained more animal-dispersed species in both the planted canopy and in the unplanted, regenerating understory than unplanted forests, and contained the highest proportion of species with use value for local people. While restoring forest increased biodiversity and accelerated forest recovery, restored forests may also represent novel ecosystems that are distinct from the region's previous ecosystems and, given their usefulness to people, are likely to be more common in the future.

An optimal proportion of mixing broad-leaved forest for enhancing the effective productivity of moso bamboo.

PubMed

Cheng, Xiao-Fei; Shi, Pei-Jian; Hui, Cang; Wang, Fu-Sheng; Liu, Guo-Hua; Li, Bai-Lian

2015-04-01

Moso bamboos (Phyllostachys edulis) are important forestry plants in southern China, with substantial roles to play in regional economic and ecological systems. Mixing broad-leaved forests and moso bamboos is a common management practice in China, and it is fundamental to elucidate the interactions between broad-leaved trees and moso bamboos for ensuring the sustainable provision of ecosystem services. We examine how the proportion of broad-leaved forest in a mixed managed zone, topology, and soil profile affects the effective productivity of moso bamboos (i.e., those with significant economic value), using linear regression and generalized additive models. Bamboo's diameter at breast height follows a Weibull distribution. The importance of these variables to bamboo productivity is, respectively, slope (25.9%), the proportion of broad-leaved forest (24.8%), elevation (23.3%), gravel content by volume (16.6%), slope location (8.3%), and soil layer thickness (1.2%). Highest productivity is found on the 25° slope, with a 600-m elevation, and 30% broad-leaved forest. As such, broad-leaved forest in the upper slope can have a strong influence on the effective productivity of moso bamboo, ranking only after slope and before elevation. These factors can be considered in future management practice.

A proposed aquatic plant community biotic index for Wisconsin lakes

USGS Publications Warehouse

Nichols, S.; Weber, S.; Shaw, B.

2000-01-01

The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value, AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.In Wisconsin, the Aquatic Macrophyte Community Index (AMCI) was developed and used to define the quality of aquatic macrophyte communities in northern Wisconsin flowages. In this study, the AMCI concept was expanded to lakes and impoundments on a statewide basis. The parameters selected were the maximum depth of plant growth, percentage of littoral area vegetated, Simpson's diversity index, relative frequen

Nonnative invasive plants of southern forests: a field guide for identification and control

Treesearch

James H. Miller

2003-01-01

Invasions of nonnative plants into forests of the Southern United States continue to go unchecked and unmonitored. Invasive nonnative plants infest under and beside forest canopies and dominate small forest openings, increasingly eroding forest productivity, hindering forest use and management activities, and degrading diversity and wildlife habitat. Often called...

Agroforestry systems of the lowland alluvial valleys of the Tehuacán-Cuicatlán Biosphere Reserve: an evaluation of their biocultural capacity.

PubMed

Vallejo, Mariana; Casas, Alejandro; Pérez-Negrón, Edgar; Moreno-Calles, Ana I; Hernández-Ordoñez, Omar; Tellez, Oswaldo; Dávila, Patricia

2015-02-19

Agroforestry systems (AFS) are valuable production systems that allow concealing benefits provision with conservation of biodiversity and ecosystem services. We analysed AFS of the zone of alluvial valleys of the Tehuacán-Cuicatlán Valley (TCV), Mexico, the most intensive agricultural systems within a region recognized for harbouring one of the most ancient agricultural experience of the New World. We hypothesized that the biodiversity conservation capacity of AFS would be directly related to traditional agricultural features and inversely related to management intensity. Agricultural practices, use frequency of machinery and chemical inputs, and proportion of forest and cultivated areas were described in 15 AFS plots in alluvial valleys of the Salado River in three villages of the region. With the information, we constructed a management intensity index and compared among plots and villages. We documented the reasons why people maintain wild plant species and traditional practices. Perennial plant species were sampled in vegetation of AFS (15 plots) and unmanaged forests (12 plots 500 m(2)) in order to compare richness, diversity and other ecological indicators in AFS and forest. In all studied sites, people combine traditional and intensive agricultural practices. Main agroforestry practices are ground terraces and borders surrounding AFS plots where people maintain vegetation. According to people, the reasons for maintaining shrubs and trees in AFS were in order of importance are: Beauty and shade provision (14% of people), fruit provision (7%), protection against strong wind, and favouring water and soil retention. We recorded 66 species of trees and shrubs in the AFS studied, 81% of them being native species that represent 38% of the perennial plant species recorded in forests sampled. Land tenure and institutions vary among sites but not influenced the actions for maintaining the vegetation cover in AFS. Plant diversity decreased with increasing agricultural intensity. Maintenance of vegetation cover did not confront markedly with the intensive agricultural practices. It is possible the expansion and enrichment of vegetation in terraces and borders of AFS. Information available on plant species and local techniques is potentially useful for a regional program of biodiversity conservation considering AFS as keystones.

Comparison of bacterial and fungal communities between natural and planted pine forests in subtropical China.

PubMed

Nie, Ming; Meng, Han; Li, Ke; Wan, Jia-Rong; Quan, Zhe-Xue; Fang, Chang-Ming; Chen, Jia-Kuan; Li, Bo

2012-01-01

To improve our understanding of the changes in bacterial and fungal diversity in natural pine and planted forests in subtropical region of China, we examined bacterial and fungal communities from a native and a nearby planted pine forest of the Mt. Lushan by constructing clone libraries of 16S and 18S rRNA genes. For bacterial communities, Proteobacteria and Acidobacteria were dominant bacterial taxa in both two types of forest soils. The Shannon-Wiener diversity index, rarefaction curve analysis, and LibShuff analysis suggest that these two forests contained similar diversity of bacterial communities. Low soil acidity (pH ≈ 4) of our study forests might be one of the most important selection factors determining growth of acidophilic Acidobacteria and Proteobacteria. However, the natural forest harbored greater level of fungal diversity than the planted forest according to the Shannon-Wiener diversity index and rarefaction curve analysis. Basidiomycota and Ascomycota were dominant fungal taxa in the soils of natural and planted forests, respectively. Our results suggest that fungal community was more sensitive than the bacterial community in characterizing the differences in plant cover impacts on the microbial flora in the natural and planted forests. The natural and planted forests may function differently due to the differences in soil fungal diversity and relative abundance.

Electrical resistivity surveys to understand vegetation-water interlinkages in a northern latitude headwater catchment

NASA Astrophysics Data System (ADS)

Soulsby, C.; Dick, J.; Tetzlaff, D.; Bradford, J.

2016-12-01

The role of vegetation on the partitioning of precipitation, and the subsequent storage and release of water within the landscape is poorly understood. In particular, the relationship between vegetation and soil moisture is complex and reciprocal. The role of soil moisture as the primary source of water to plants may affect vegetation distribution. In turn, the structure of vegetation canopies may regulate water partitioning into interception, throughfall and steam flow. Such spatial differences in the inputs, together with complex patterns of water uptake from highly distributed root networks can create marked heterogeneity in soil moisture dynamics at small scales. Here, we present a study combining 3D and 2D ERT surveys with soil moisture measurements in a 3.2km upland catchment in the Scottish Highlands to understand influences of different vegetation types on spatio-temporal dynamics in soil moisture. The study focussed on one year of fortnightly ERT surveys to investigate plant-soil-water interactions within the root zone in podzolic soils. Locations were selected in both forest stands of 15m high Scots pine (Pinus sylvestris) and non-forest locations dominated by heather (Calluna vulgaris) shrubs (<0.5m high). These dominant species are typical of forest and non-forest vegetation communities in the Scottish Highlands. Results showed differences in the soil moisture dynamics under the different vegetation types, with heterogeneous patterns in the forested site mainly correlated with canopy cover and mirroring interception losses, with pronounced wetting cycles of the soil surrounding the bole of trees as a consequence of stem flow. Temporal variability in the forested site was greater, probably due to the interception, and increased evapotranspiration losses relative to the heather site, with drying typically being focussed on the areas around the trees, and reflecting the amount of water uptake. Moisture changes in the heather site were fairly heterogeneous are related to micro-topographic affects, lower interception ( 30% compared with 45%) and a smaller microclimatic effect of the canopy which serves to create greater fluctuations in soil moisture. Our results confirm the value in using geophysics to spatially elucidate subsurface plant-soil-water interactions.

Deforestation and forest fires in Roraima and their relationship with phytoclimatic regions in the northern Brazilian Amazon.

PubMed

Barni, Paulo Eduardo; Pereira, Vaneza Barreto; Manzi, Antonio Ocimar; Barbosa, Reinaldo Imbrozio

2015-05-01

Deforestation and forest fires in the Brazilian Amazon are a regional-scale anthropogenic process related to biomass burning, which has a direct impact on global warming due to greenhouse gas emissions. Containment of this process requires characterizing its spatial distribution and that of the environmental factors related to its occurrence. The aim of this study is to investigate the spatial and temporal distribution of deforested areas and forest fires in the State of Roraima from 2000 to 2010. We mapped deforested areas and forest fires using Landsat images and associated their occurrence with two phytoclimatic zones: zone with savanna influence (ZIS), and zone without savanna influence (ZOS). Total deforested area during the interval was estimated at 3.06 × 10(3) km(2) (ZIS = 55 %; ZOS = 45 %) while total area affected by forest fires was estimated at 3.02 × 10(3) km(2) (ZIS = 97.7 %; ZOS = 2.3 %). Magnitude of deforestation in Roraima was not related to the phytoclimatic zones, but small deforested areas (≤17.9 ha) predominated in ZOS while larger deforestation classes (>17.9 ha) predominated in ZIS, which is an area with a longer history of human activities. The largest occurrence of forest fires was observed in the ZIS in years with El Niño events. Our analysis indicates that the areas most affected by forest fires in Roraima during 2000-2010 were associated with strong climatic events and the occurrence these fires was amplified in ZIS, a sensitive phytoclimatic zone with a higher risk of anthropogenic fires given its drier climate and open forest structure.

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 framework for future construction of models that account for the temporal dynamics of P in decomposing litter. Copyright © 2018 Elsevier B.V. All rights reserved.

Variation in carbon storage and its distribution by stand age and forest type in boreal and temperate forests in northeastern China.

PubMed

Wei, Yawei; Li, Maihe; Chen, Hua; Lewis, Bernard J; Yu, Dapao; Zhou, Li; Zhou, Wangming; Fang, Xiangmin; Zhao, Wei; Dai, Limin

2013-01-01

The northeastern forest region of China is an important component of total temperate and boreal forests in the northern hemisphere. But how carbon (C) pool size and distribution varies among tree, understory, forest floor and soil components, and across stand ages remains unclear. To address this knowledge gap, we selected three major temperate and two major boreal forest types in northeastern (NE) China. Within both forest zones, we focused on four stand age classes (young, mid-aged, mature and over-mature). Results showed that total C storage was greater in temperate than in boreal forests, and greater in older than in younger stands. Tree biomass C was the main C component, and its contribution to the total forest C storage increased with increasing stand age. It ranged from 27.7% in young to 62.8% in over-mature stands in boreal forests and from 26.5% in young to 72.8% in over-mature stands in temperate forests. Results from both forest zones thus confirm the large biomass C storage capacity of old-growth forests. Tree biomass C was influenced by forest zone, stand age, and forest type. Soil C contribution to total forest C storage ranged from 62.5% in young to 30.1% in over-mature stands in boreal and from 70.1% in young to 26.0% in over-mature in temperate forests. Thus soil C storage is a major C pool in forests of NE China. On the other hand, understory and forest floor C jointly contained less than 13% and <5%, in boreal and temperate forests respectively, and thus play a minor role in total forest C storage in NE China.

Variation in Carbon Storage and Its Distribution by Stand Age and Forest Type in Boreal and Temperate Forests in Northeastern China

PubMed Central

Wei, Yawei; Li, Maihe; Chen, Hua; Lewis, Bernard J.; Yu, Dapao; Zhou, Li; Zhou, Wangming; Fang, Xiangmin; Zhao, Wei; Dai, Limin

2013-01-01

The northeastern forest region of China is an important component of total temperate and boreal forests in the northern hemisphere. But how carbon (C) pool size and distribution varies among tree, understory, forest floor and soil components, and across stand ages remains unclear. To address this knowledge gap, we selected three major temperate and two major boreal forest types in northeastern (NE) China. Within both forest zones, we focused on four stand age classes (young, mid-aged, mature and over-mature). Results showed that total C storage was greater in temperate than in boreal forests, and greater in older than in younger stands. Tree biomass C was the main C component, and its contribution to the total forest C storage increased with increasing stand age. It ranged from 27.7% in young to 62.8% in over-mature stands in boreal forests and from 26.5% in young to 72.8% in over-mature stands in temperate forests. Results from both forest zones thus confirm the large biomass C storage capacity of old-growth forests. Tree biomass C was influenced by forest zone, stand age, and forest type. Soil C contribution to total forest C storage ranged from 62.5% in young to 30.1% in over-mature stands in boreal and from 70.1% in young to 26.0% in over-mature in temperate forests. Thus soil C storage is a major C pool in forests of NE China. On the other hand, understory and forest floor C jointly contained less than 13% and <5%, in boreal and temperate forests respectively, and thus play a minor role in total forest C storage in NE China. PMID:23977252

The influence of habitat structure on bird species composition in lowland malaysian rain forests.

PubMed

Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd

2012-05-01

Bird surveys were conducted in the Bukit Kepala Gajah limestone area in Lenggong, Perak from July 2010 to January 2011. The study area was divided into three zones: forest edge, forest intermediate and forest interior. A point-count distance sampling method was used in the bird surveys. The study recorded 7789 detections, representing 100 bird species belonging to 28 families. Pycnonotidae, Timaliidae and Nectariniidae were the dominant families overall and showed the highest number of observations recorded in the study area whereas Motacillidae showed the fewest observations. The bird species were grouped into three feeding guilds: insectivores, frugivores and others (omnivores, carnivores, nectarivores and granivores). The species richness of insectivorous birds differed significantly among the forest zones sampled (Kruskal-Wallis: α=0.05, H=10.979, d.f.=2, p=0.004), with more insectivorous birds occurring in the forest interior. No significant differences were found among the zones in the species richness of either the frugivore guild or the composite others guild.

The Influence of Habitat Structure on Bird Species Composition in Lowland Malaysian Rain Forests

PubMed Central

Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd

2012-01-01

Bird surveys were conducted in the Bukit Kepala Gajah limestone area in Lenggong, Perak from July 2010 to January 2011. The study area was divided into three zones: forest edge, forest intermediate and forest interior. A point-count distance sampling method was used in the bird surveys. The study recorded 7789 detections, representing 100 bird species belonging to 28 families. Pycnonotidae, Timaliidae and Nectariniidae were the dominant families overall and showed the highest number of observations recorded in the study area whereas Motacillidae showed the fewest observations. The bird species were grouped into three feeding guilds: insectivores, frugivores and others (omnivores, carnivores, nectarivores and granivores). The species richness of insectivorous birds differed significantly among the forest zones sampled (Kruskal-Wallis: α=0.05, H=10.979, d.f.=2, p=0.004), with more insectivorous birds occurring in the forest interior. No significant differences were found among the zones in the species richness of either the frugivore guild or the composite others guild. PMID:24575221

Linking Above- and Belowground Dynamics in Tropical Urban Forests

NASA Astrophysics Data System (ADS)

Atkinson, E. E.; Marin-Spiotta, E.

2013-12-01

Secondary forests that emerge after a long history of agriculture can have altered plant community composition and relative abundances of different species. These forests can look and behave differently compared to pre-agricultural forests due changes in primary productivity, resource allocation, and phenology, which can significantly affect processes such as carbon accumulation and nutrient availability. Our research explores how alternative successional trajectories following intensive agricultural use affect linkages among the establishment of novel plant communities, soil nutrient availability and turnover, and soil microbial community composition and function. We hypothesize that different plant species composition due to differing land use legacies and successional trajectories would drive changes in soil microbial community structure and function, affecting soil C and N chemistry and turnover. We conducted this research in the subtropical dry forest life zone of St. Croix, U.S. Virgin Islands where island-wide abandonment of sugarcane resulted in a mosaic of sites in different stages of forest succession. We identified replicate sites with the following post-sugarcane trajectories: 1) natural forest regeneration, 2) low intensity pasture use, followed by reforestation with timber plantation, which are no longer being managed, 3) high intensity pasture use and recent natural forest regeneration, and 4) high intensity pasture use and current active grazing. During 2011-2013, we sampled soils seasonally (0-10 cm) and measured tree species composition. The successional trajectories showed distinct tree species composition. The first two trajectories yielded 40-year old mixed-species secondary forest, dominated by the dry forest tree species Melicoccus bijugatas, Guapira fragrans, Maniklara zapota, and Sideroxylon foetidissimum. The tree species Melicoccus bijugatas primarily drove differences between the first two trajectories (natural forest regeneration vs. timber plantation and subsequent forest regeneration) while the N-fixing species Leucaena leucocephala drove differences between these forests and younger forests (10-year old), which only recently regenerated. The 40-year old mixed-species forests, regardless of successional trajectory, both had higher soil organic C and N (40 × 6 Mg C/ha and 3.8 × 6 Mg N/ha) compared to younger forests (32 × 2 Mg C/ha and 2.9 × 0.2 Mg N/ha) and active pastures. Active pastures had the lowest soil organic C and N (22 × 6 Mg C/ha and 2.1 × 0.5 Mg N/ha). We found that each successional trajectory showed distinct soil microbial community composition. In addition, the recently regenerated younger forests, dominated by N-fixing tree species, had higher microbial biomass and higher rates of N-cycling enzyme activity (N-acetyl glucosaminidase) when compared with the older, mixed-species forest. Our next step is to link microbial community structure and function with distinct forms of soil organic matter (SOM), and thus determine whether changes in function create distinct SOM stabilization pathways. To do this we will compare SOM chemistry and turnover for the different successional trajectories and analyze data from long-term leaf litter and root transplant experiments between the young and old secondary forests.

Ecological plasticity of Trichoderma fungi in leached chernozem

NASA Astrophysics Data System (ADS)

Svistova, I. D.; Senchakova, T. Yu.

2010-03-01

The autecological properties of Trichoderma fungi ecotypes isolated from the leached chernozem of the forest-steppe zone of the European part of Russia have been studied. We were the first who carried out the complex study of the synecological relations of micromycetes of such kinds in a system including the soil, microbial community, and plants, i.e., their relations with soil saprotrophic fungi, bacteria, actinomycetes, plants, and pathogenic fungi. It was shown that the ecological plasticity of the Trichoderma genus in the soil of this zone is determined by its growth rate, the optimum pH and temperature, the biosynthesis of extracellular hydrolytic enzymes, the biological action of mycotoxins, and the ability for parasitism. The efficiency of the introduction of Trichoderma species typical and atypical for the leached chernozem into this soil and their influence on the structure of the microbial community were evaluated. The T. pseudokoningii ecotype, which produces cellulolytic enzymes, is very promising for industrial biotechnology, and the T. harzianum ecotype can be used in soil biotechnology for the biocontrol of chernozem. The addition of a commercial trichodermin preparation into the chernozem damages the structure of its microbial community.

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

Farfan, E.; Jannik, T.

This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals, and reviews interspecies differences in radionuclide accumulations and factors affecting the radionuclide accumulations. It is shown that bioavailability of radionuclides in the 'soil-to-plant' chain and a trophic specialization of animals play key roles in determining their actual contamination levels. The total absorbed dose rates in small mammals significantly reduced during the years following the Chernobyl Nuclear Power Plant accident.more » In 1986, the absorbed dose rate reached 1.3-6.0 Gy hr{sup -1} in the central areas of the Chernobyl Exclusion Zone (the 'Red Forest'). In 1988 and 1990, the total absorbed dose rates were 1.3 and 0.42 Gy hr{sup -1}, respectively. In 1995, 2000, and 2005, according to the present study, the total absorbed dose rates rarely exceeded 0.00023, 0.00018, and 0.00015 Gy hr{sup -1}, respectively. Contributions of individual radiation sources into the total absorbed dose are described.« less

Layout Guide for Burnt and Un-burnt Tropical Forest: The Diversity of Forest Plants and Insetcs for Sustainable Environmental

NASA Astrophysics Data System (ADS)

Watiniasih, N. L.; Tambunan, J.; Merdana, I. M.; Antara, I. N. G.

2018-04-01

Forest fire is a common phenomenon in tropical forest likes in Indonesia. Beside the effect of soaring heat and lack of rain during dry season due to the tropical climate, farming system is also reported as one reason of forest fire in Indonesia. People of surrounding areas and neighbouring countries are suffering from the effect of forest fire. Plants and animals are the most suffer from this occurrence that they cannot escape. This study aimed to investigate the effect of previously burnt and un-burnt tropical forest in Borneo Island on the plant and insect diversity of the tropical forest. The result of the study found that the plants in previously burnt forest area was dominated by one species, while higher and more stable plant diversity was found in un-burnt forest. Although the number of individual insects was higher in previously burnt tropical forest, but the insects was more diverse in un-burnt tropical forest. The alteration of environmental conditions in previously burnt and un-burnt forest indicate that the energy held in natural forest support higher number and more stable insects than previously burnt forest.

Aridification as a driver of biodiversity: a case study for the cycad genus Dioon (Zamiaceae).

PubMed

Said Gutiérrez-Ortega, José; Yamamoto, Takashi; Vovides, Andrew P; Angel Pérez-Farrera, Miguel; Martínez, José F; Molina-Freaner, Francisco; Watano, Yasuyuki; Kajita, Tadashi

2018-01-25

Aridification is considered a selective pressure that might have influenced plant diversification. It is suggested that plants adapted to aridity diversified during the Miocene, an epoch of global aridification (≈15 million years ago). However, evidence supporting diversification being a direct response to aridity is scarce, and multidisciplinary evidence, besides just phylogenetic estimations, is necessary to support the idea that aridification has driven diversification. The cycad genus Dioon (Zamiaceae), a tropical group including species occurring from humid forests to arid zones, was investigated as a promising study system to understand the associations among habitat shifts, diversification times, the evolution of leaf epidermal adaptations, and aridification of Mexico. A phylogenetic tree was constructed from seven chloroplast DNA sequences and the ITS2 spacer to reveal the relationships among 14 Dioon species from habitats ranging from humid forests to deserts. Divergence times were estimated and the habitat shifts throughout Dioon phylogeny were detected. The epidermal anatomy among Dioon species was compared and correlation tests were performed to associate the epidermal variations with habitat parameters. Events of habitat shifts towards arid zones happened exclusively in one of the two main clades of Dioon. Such habitat shifts happened during the species diversification of Dioon, mainly during the Miocene. Comparative anatomy showed epidermal differences between species from arid and mesic habitats. The variation of epidermal structures was found to be correlated with habitat parameters. Also, most of the analysed epidermal traits showed significant phylogenetic signals. The diversification of Dioon has been driven by the aridification of Mexico. The Miocene timing corresponds to the expansion of arid zones that embedded the ancestral Dioon populations. As response, species in arid zones evolved epidermal traits to counteract aridity stress. This case study provides a robust body of evidence supporting the idea that aridification is an important driver of biodiversity. © The Authors 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The impact of land-use change from forest to oil palm on soil greenhouse gas and volatile organic compound fluxes in Malaysian Borneo

NASA Astrophysics Data System (ADS)

Drewer, Julia; Leduning, Melissa; Kerdraon-Byrne, Deirdre; Sayer, Emma; Sentien, Justin; Skiba, Ute

2017-04-01

Monocultures of oil palm have expanded in SE Asia, and more recently also in Africa and South America, frequently replacing tropical forests. The limited data available clearly show that this conversion is associated with a potentially large greenhouse gas (GHG) burden. The physical process of land-use change, such is felling, drainage and ploughing can significantly increase emissions of N2O and soil CO2 respiration and decrease CH4 oxidation rates in the short term; and in the long-term regular nitrogen applications will impact in particular soil N2O fluxes. Little is known about volatile organic compound (VOC) fluxes from soil and litter in tropical forests and their speciation or about the links between GHG and VOC fluxes. VOC emissions are important as they directly and indirectly influence the concentrations and lifetimes of air pollutants and GHGs. For example, oxidation of VOCs generate tropospheric ozone which is also a potent GHG. Within ecosystems, monoterpenes can mediate plant-microbe and plant- interactions and protect photosynthesis during abiotic stress. However, little is known about monoterpene composition in the tropics - a widely recognized major global source of terpenoids to the atmosphere. These knowledge gaps make it difficult for developing countries in the tropics, especially SE Asia, to develop effective mitigation strategies. Current understanding of soil GHG fluxes associated with land-use change from forest to oil palm is not sufficient to provide reliable estimates of their carbon footprints and sustainability or advice on GHG mitigation strategies. To provide the necessary data we have installed a total of 56 flux chambers in logged forests, forest fragments and mature and young oil palm plantations as well as riparian zones within the SAFE landscape in SE Sabah (Stability of Altered Forest Ecosystems; http://www.safeproject.net). Soil respiration rates, N2O, CH4 and VOC fluxes together with soil moisture, pH, mineral and total C and N were measured over a two year period. Additionally the effects of changes in forest litter diversity on soil properties were investigated using mesocosms. For this experiment leaf litter was transplanted into different forest types and oil palm plantations of different stand ages to simulate the change in litter-fall caused by changes in above ground plant composition. Laboratory incubations using soil and litter from the field sites provide additional detailed data on soil properties, carbon storage capacity and microbial activity to identify potential mechanisms for the field observations.

Phytoplankton assemblages in high-elevation lakes in the northern Cascade Mountains, Washington State, USA

USGS Publications Warehouse

Larson, Gary L.; McIntire, C.D.; Truitt, R.E.; Liss, W.J.; Hoffman, Robert L.; Deimling, E.; Lomnicky, G.A.

1998-01-01

Phytoplankton assemblages in high-elevation lakes of North Cascades National Park Service Complex were studied during the open-water period in 1989. Collectively, 93 taxa were identified in 55 samples from 51 lakes. Based on cell densities, cyanobacteria had the highest relative abundance (36.7 %), followed by chlorophytes (29.8 %), and chrysophytes (19.6 %). Aphanocapsa delicatissima had the highest proportional abundance (14.0 %). Only 15.1 % percent of the taxa occurred in more than 20 samples. Phytoplankton cell densities increased following a gradient of increasing lake-water temperature, alkalinity, and concentration of total Kjeldahl-N with decreasing lake elevation. Chrysophytes and cyanobacteria were quantitatively (relative abundance) the most important taxa in alpine and subalpine lakes, whereas cyanobacteria had the highest relative abundances in high-forest and low-forest lakes. Chlorophytes had their highest relative abundance in high-forest lakes. Although low in relative abundance, diatoms and dinoflagellates were most abundant in alpine lakes. An ordination by correspondence analysis indicated that most alpine, subalpine, and high-forest lakes had similar floras. Although a few subalpine lakes exhibited deviations from this pattern, the main differences in phytoplankton composition were found in a group of low-forest and high-forest lakes. Canonical correspondence analysis (CCA) provided evidence that the distribution of samples and taxa in ordination space was correlated with a gradient of decreasing lake elevation and increasing water temperature, alkalinity, and concentration of nitrogen. When CCA was used to examine relationships among phytoplankton taxa and vegetation zones, a continuous distribution of taxa was found from the low-forest zone to the subalpine zone, with a large number of taxa occurring primarily in the subalpine and high-forest zones. Three phytoplankton taxa occurred primarily in alpine lakes, whereas five taxa co-occurred in alpine, subalpine, and high forest zones. Collectively, lake elevation and associated changes in water quality and concentrations of nutrients, especially nitrogen, appeared to be the primary physical and chemical factors influencing the taxonomic structures of phytoplankton assemblages.

[Current approach to zoning atomic shipbuilding plants].

PubMed

Blekher, A Ia

2005-01-01

The paper discusses the currently introduced radiation-and-hygienic system for zoning atomic shipbuilding plants, in accordance with which three radiation-and-hygienic zones (a strict regime zone, a controlled approach zone, and a free regime zone) are established at the plant site and two zones (a sanitary-and-protective zone and a follow-up zone) are also established outside the plant site.

Predicting the impact of land management decisions on overland flow generation: Implications for cesium migration in forested Fukushima watersheds

NASA Astrophysics Data System (ADS)

Siirila-Woodburn, Erica R.; Steefel, Carl I.; Williams, Kenneth H.; Birkholzer, Jens T.

2018-03-01

The effects of land use and land cover (LULC) change on environmental systems across the land surface's "critical zone" are highly uncertain, often making prediction and risk management decision difficult. In a series of numerical experiments with an integrated hydrologic model, overland flow generation is quantified for both present day and forest thinning scenarios. A typhoon storm event in a watershed near the Fukushima Dai-ichi Nuclear Power Plant is used as an example application in which the interplay between LULC change and overland flow generation is important given that sediment-bound radionuclides may cause secondary contamination via surface water transport. Results illustrate the nonlinearity of the integrated system spanning from the deep groundwater to the atmosphere, and provide quantitative tools when determining the tradeoffs of different risk-mitigation strategies.

Might rock moisture in shallow fractured bedrock underlying hillslopes provide vegetation resilience to future droughts?

NASA Astrophysics Data System (ADS)

Dietrich, W. E.; Dawson, T. E.; Salve, R.; Simonin, K. A.; Oshun, J.; Rempe, D.; Fung, I.

2009-12-01

Hilly and mountainous landscapes are often capped by relatively thin soil that mantles a thicker, but nonetheless relatively shallow fractured bedrock zone. The few studies that have quantitatively explored this near-surface zone have demonstrated that subsurface runoff, saturation overland flow, and pore pressure development are dominated by pathways through the bedrock—not through the soil. Hence, evolution of this weathered fractured zone, and its spatial variation strongly influences hydrologic and geomorphic processes. Here we report findings at a new study site (“Rivendell”) in the South Fork Eel River watershed in the Northern Coastal California area, where periods of essentially no rain can extend 5 to 6 months, yet 60 m tall conifer trees can prosper and continuous baseflow in modest sized drainages can sustain aquatic ecosystems. Dominant vegetation in the region correlates with lithology and we hypothesize that it is the extent of development of the shallow fractured bedrock that controls this relationship. To explore the linkages between climate, vegetation, and hydrology as mediated by bedrock conditions we have instrumented a 4000 m2 steep (32 degree) catchment under old-growth Douglas fir forest with a large number (over 300) of devices including rain gauges, temperature, humidity and soil moisture probes, TDR arrays, sap flow monitors and pressure transducers in wells—all of which report via a wireless solar powered system back to Berkeley for effectively real-time monitoring. Electrical resistivity tomography surveys have been repeatedly performed. Seven deep (up to 30 m) wells along the catchment reveal a ~20 m thick weathered, fractured bedrock zone that tapers downslope to about 7 m. Two years of monitoring show that all water passes through the shallow soil into the bedrock zone where it eventually collects at the base of the fracture zone, forming a dynamic perched groundwater table that generates storm runoff and slowly drops during the summer (controlling river baseflow). Sap flow measurements show strong seasonal response, and flow reversal, i.e. flow returning to the feeding root system at night. Together these data suggest the hypotheses that: 1) in the dry summers trees use “hydraulic lift” to exploit seasonally recharged rock moisture at depth (in the unsaturated zone above the groundwater table) and store this water in the soil in the evening (possibly benefiting lower canopy plants), 2) this process could provide a forest ecosystem resilience to the expanding droughts anticipated for California, and 3) available rock moisture depends on rock type and whether the shallow fractured rock zone develops. Rock moisture is missing from global climate models, and its availability to plants may strongly influence vegetation response and changes in regional climate.

The Pleistocene biogeography of eastern North America: A nonmigration scenario for deciduous forest

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

Loehle, C.; Iltis, H.

The current reconstruction of the vegetation of eastern North America at the last glacial maximum postulates a very wide zone of tundra and boreal forest south of the ice. This reconstruction requires that the deciduous forest retreated far to the south. The authors believe that this reconstruction is seriously in error. Geologic evidence for glacial activity or tundra is absent from the southern Appalachians. Positive evidence for boreal forest is based on pollen identifications for Picea, Betula, and Pinus, when in reality southern members of these genera have pollen that cannot be distinguished from that of northern members. Further, pollenmore » of typical southern species such as oaks and hickories occurs throughout profiles that past authors had labeled boreal. Pollen evidence for a far southern deciduous forest refuge is lacking. Data on endemics are particularly challenging for the scenario in which deciduous forest migrated to the south and back. The southern Appalachian region is rife with endemics that are often extreme-habitat specialists unable to migrate. The previously glaciated zone is almost completely lacking in endemics. Outlier populations, range boundaries, and absence of certain hybrids all argue against a large boreal zone. The new reconstruction postulates a cold zone no more than 75--100 miles wide south of the ice in the East.« less

Dynamic model of forest area on flood zone of Padang City, West Sumatra Province-Indonesia

NASA Astrophysics Data System (ADS)

Dewata, Indang; Iswandi, U.

2018-05-01

The flood disaster has caused many harm to human life, and the change of watershed characteristic is one of the factors causing the flood disaster. The increase of deforestation due to the increase of water causes the occurrence of flood disaster in the rainy season. The research objective was to develop a dynamic model of forest on flood hazard zone using powersim 10.1. In model development, there are three scenarios: optimistic, moderate, and pessimistic. The study shows that in Padang there are about 13 percent of high flood hazard zones. Deforestation of 4.5 percent/year is one cause that may increased the flooding intensity in Padang. There will be 14 percent of total forest area when management policy of forest absence in 2050.

CHRONIC IRRADIATION OF SCOTS PINE TREES (PINUS SYLVESTRIS) IN THE CHERNOBYL EXCLUSION ZONE: DOSIMETRY AND RADIOBIOLOGICAL EFFECTS

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

Farfan, E.; Jannik, T.

To identify effects of chronic internal and external radiation exposure for components of terrestrial ecosystems, a comprehensive study of Scots pine trees in the Chernobyl Exclusion Zone was performed. The experimental plan included over 1,100 young trees (up to 20 years old) selected from areas with varying levels of radioactive contamination. These pine trees were planted after the 1986 Chernobyl Nuclear Power Plant accident mainly to prevent radionuclide resuspension and soil erosion. For each tree, the major morphological parameters and radioactive contamination values were identified. Cytological analyses were performed for selected trees representing all dose rate ranges. A specially developedmore » dosimetric model capable of taking into account radiation from the incorporated radionuclides in the trees was developed for the apical meristem. The calculated dose rates for the trees in the study varied within three orders of magnitude, from close to background values in the control area (about 5 mGy y{sup -1}) to approximately 7 Gy y{sup -1} in the Red Forest area located in the immediate vicinity of the Chernobyl Nuclear Power Plant site. Dose rate/effect relationships for morphological changes and cytogenetic defects were identified and correlations for radiation effects occurring on the morphological and cellular level were established.« less

Specialization and interaction strength in a tropical plant-frugivore network differ among forest strata.

PubMed

Schleuning, Matthias; Blüthgen, Nico; Flörchinger, Martina; Braun, Julius; Schaefer, H Martin; Böhning-Gaese, Katrin

2011-01-01

The degree of interdependence and potential for shared coevolutionary history of frugivorous animals and fleshy-fruited plants are contentious topics. Recently, network analyses revealed that mutualistic relationships between fleshy-fruited plants and frugivores are mostly built upon generalized associations. However, little is known about the determinants of network structure, especially from tropical forests where plants' dependence on animal seed dispersal is particularly high. Here, we present an in-depth analysis of specialization and interaction strength in a plant-frugivore network from a Kenyan rain forest. We recorded fruit removal from 33 plant species in different forest strata (canopy, midstory, understory) and habitats (primary and secondary forest) with a standardized sampling design (3447 interactions in 924 observation hours). We classified the 88 frugivore species into guilds according to dietary specialization (14 obligate, 28 partial, 46 opportunistic frugivores) and forest dependence (50 forest species, 38 visitors). Overall, complementary specialization was similar to that in other plant-frugivore networks. However, the plant-frugivore interactions in the canopy stratum were less specialized than in the mid- and understory, whereas primary and secondary forest did not differ. Plant specialization on frugivores decreased with plant height, and obligate and partial frugivores were less specialized than opportunistic frugivores. The overall impact of a frugivore increased with the number of visits and the specialization on specific plants. Moreover, interaction strength of frugivores differed among forest strata. Obligate frugivores foraged in the canopy where fruit resources were abundant, whereas partial and opportunistic frugivores were more common on mid- and understory plants, respectively. We conclude that the vertical stratification of the frugivore community into obligate and opportunistic feeding guilds structures this plant-frugivore network. The canopy stratum comprises stronger links and generalized associations, whereas the lower strata are composed of weaker links and more specialized interactions. Our results suggest that seed-dispersal relationships of plants in lower forest strata are more prone to disruption than those of canopy trees.

High-resolution vegetation dynamics reconstitution in the Zaire/Congo watershed since MIS 6

NASA Astrophysics Data System (ADS)

Dalibard, Mathieu; Popescu, Speranta-Maria; Maley, Jean; Pittet, Bernard; Marsset, Tania; Baudin, François; Dennielou, Bernard; Sionneau, Thomas; Escarguel, Gilles; Droz, Laurence

2010-05-01

The present-day latitudinal migrations of the Intertropical Convergence Zone (ITCZ) are controlled by ocean/atmosphere dynamics impact seasonality of monsoon influence on the intertropical eastern Atlantic and western Africa. The geographical position of the Zaire/Congo drainage basin spanning the Northern and Southern hemispheres makes it a key area to study variation of the climatic parameters (temperature and monsoon activity) through time. To identify the ITCZ variability during the last 180 ka, a multiproxy analysis (pollen grains, elemental ratio derived from XRF analysis, organic matter content, clay mineralogy) was performed on the core KZAI-02, drilled offshore Angola at 3418 m water depth. Pollen record indicates a very high plant diversity (327 taxa representative of 106 families). They have been grouped as follow with respect to their ecological requirements: (1) mangrove, (2) rain forest, (3) warm-temperate forest, (4) pioneer forest, (5) afromontane forest, (6) savannah, (7) marshes. The relative fluctuation of these ecological groups during the last 180 ka allows us to reconstruct the dynamics of vegetation and its response to global climate forcing. Generally the glacial periods are characterized by the development of the afromontane forest (mainly Podocarpus) on reliefs while in lower altitudes the savannah (Fabaceae Papilionoidae, Poaceae, Zygophyllum, etc.) spreads in response to the relative precipitation decrease. During interglacials our records indicate a progressive development of forest environments, the pioneer forest (Alchornea, Bridelia, Cnestis, etc.) being progressively replaced by the tropical rain forest (Acanthaceae, Fabaceae Caesalpinoideae, Sapotaceae, etc.). This evolution indicates an increase in temperature and humidity. At the stadial/interglacial transitions the development of the mangrove (Rhizophoraceae, Avicenia, Sonneratia, etc.) seems to respond principally to sea level rise. The maximum extension of Cyperaceae marshes contemporaneously with a significant presence of afromontane forest in MIS 6 may be correlated with rainfall increase probably related to changes in the monsoon activity. The information in term of humidity obtained from some other proxies (clay mineralogy, organic carbon, and elemental ratio measured by XRF, such as Br, etc.) shows a similar trend with the pollen record. A spectral analysis has been performed and reveals that the reconstructed climatic parameters from the Zaire/Congo watershed correlated with Milankovitch cycles, including semi-precession cycles (10 kyrs) characteristic of the Equatorial zone.

Reconstructing the Mexican Tropical Dry Forests via an Autoecological Niche Approach: Reconsidering the Ecosystem Boundaries

PubMed Central

Prieto-Torres, David A.; Rojas-Soto, Octavio R.

2016-01-01

We used Ecological Niche Modeling (ENM) of individual species of two taxonomic groups (plants and birds) in order to reconstruct the climatic distribution of Tropical Dry Forests (TDFs) in Mexico and to analyze their boundaries with other terrestrial ecosystems. The reconstruction for TDFs’ distribution was analyzed considering the prediction and omission errors based upon the combination of species, obtained from the overlap of individual models (only plants, only birds, and all species combined). Two verifications were used: a primary vegetation map and 100 independent TDFs localities. We performed a Principal Component (PCA) and Discriminant Analysis (DA) to evaluate the variation in the environmental variables and ecological overlap among ecosystems. The modeling strategies showed differences in the ecological patterns and prediction areas, where the “all species combined” model (with a threshold of ≥10 species) was the best strategy to use in the TDFs reconstruction. We observed a concordance of 78% with the primary vegetation map and a prediction of 98% of independent locality records. Although PCA and DA tests explained 75.78% and 97.9% of variance observed, respectively, we observed an important overlap among the TDFs with other adjacent ecosystems, confirming the existence of transition zones among them. We successfully modeled the distribution of Mexican TDFs using a number of bioclimatic variables and co-distributed species. This autoecological niche approach suggests the necessity of rethinking the delimitations of ecosystems based on the recognition of transition zones among them in order to understand the real nature of communities and association patterns of species. PMID:26968031

Successional and seasonal variations in soil and litter microbial community structure and function during tropical postagricultural forest regeneration: a multiyear study.

PubMed

Smith, A Peyton; Marín-Spiotta, Erika; Balser, Teri

2015-09-01

Soil microorganisms regulate fundamental biochemical processes in plant litter decomposition and soil organic matter (SOM) transformations. Understanding how microbial communities respond to changes in vegetation is critical for improving predictions of how land-cover change affects belowground carbon storage and nutrient availability. We measured intra- and interannual variability in soil and forest litter microbial community composition and activity via phospholipid fatty acid analysis (PLFA) and extracellular enzyme activity across a well-replicated, long-term chronosequence of secondary forests growing on abandoned pastures in the wet subtropical forest life zone of Puerto Rico. Microbial community PLFA structure differed between young secondary forests and older secondary and primary forests, following successional shifts in tree species composition. These successional patterns held across seasons, but the microbial groups driving these patterns differed over time. Microbial community composition from the forest litter differed greatly from those in the soil, but did not show the same successional trends. Extracellular enzyme activity did not differ with forest succession, but varied by season with greater rates of potential activity in the dry seasons. We found few robust significant relationships among microbial community parameters and soil pH, moisture, carbon, and nitrogen concentrations. Observed inter- and intrannual variability in microbial community structure and activity reveal the importance of a multiple, temporal sampling strategy when investigating microbial community dynamics with land-use change. Successional control over microbial composition with forest recovery suggests strong links between above and belowground communities. © 2015 John Wiley & Sons Ltd.

Mangrove plantation over a limestone reef - Good for the ecology?

NASA Astrophysics Data System (ADS)

Asaeda, Takashi; Barnuevo, Abner; Sanjaya, Kelum; Fortes, Miguel D.; Kanesaka, Yoshikazu; Wolanski, Eric

2016-05-01

There have been efforts to restore degraded tropical and subtropical mangrove forests. While there have been many failures, there have been some successes but these were seldom evaluated to test to what level the created mangrove wetlands reproduce the characteristics of the natural ecosystem and thus what ecosystem services they can deliver. We provide such a detailed assessment for the case of Olango and Banacon Islands in the Philippines where the forest was created over a limestone reef where mangroves did not exist in one island but they covered most of the other island before deforestation in the 1940s and 1950s. The created forest appears to have reached a steady state after 60 years. As is typical of mangrove rehabilitation efforts worldwide, planting was limited to a single Rhizophora species. While a forest has been created, it does not mimic a natural forest. There is a large difference between the natural and planted forests in terms of forest structure and species diversity, and tree density. The high density of planted trees excludes importing other species from nearby natural forests; therefore the planted forest remains mono-specific even after several decades and shows no sign of mimicking the characteristics of a natural forest. The planted forests provided mangrove propagules that invaded nearby natural forests. The planted forest has also changed the substratum from sandy to muddy. The outline of the crown of the planted forest has become smooth and horizontal, contrary to that of a natural forest, and this changes the local landscape. Thus we recommend that future mangrove restoration schemes should modify their methodology in order to plant several species, maintain sufficient space between trees for growth, include the naturally dominant species, and create tidal creeks, in order to reproduce in the rehabilitated areas some of the key ecosystem characteristics of natural mangrove forests.

Large-scale parallel 454 sequencing reveals host ecological group specificity of arbuscular mycorrhizal fungi in a boreonemoral forest.

PubMed

Opik, M; Metsis, M; Daniell, T J; Zobel, M; Moora, M

2009-10-01

* Knowledge of the diversity of arbuscular mycorrhizal fungi (AMF) in natural ecosystems is a major bottleneck in mycorrhizal ecology. Here, we aimed to apply 454 sequencing--providing a new level of descriptive power--to assess the AMF diversity in a boreonemoral forest. * 454 sequencing reads of the small subunit ribosomal RNA (SSU rRNA) gene of Glomeromycota were assigned to sequence groups by blast searches against a custom-made annotated sequence database. * We detected 47 AMF taxa in the roots of 10 plant species in a 10 x 10 m plot, which is almost the same as the number of plant species in the whole studied forest. There was a significant difference between AMF communities in the roots of forest specialist plant species and in the roots of habitat generalist plant species. Forest plant species hosted 22 specialist AMF taxa, and the generalist plants shared all but one AMF taxon with forest plants, including globally distributed generalist fungi. These AMF taxa that have been globally recorded only in forest ecosystems were significantly over-represented in the roots of forest plant species. * Our findings suggest that partner specificity in AM symbiosis may occur at the level of ecological groups, rather than at the species level, of both plant and fungal partners.

AmeriFlux US-CZ2 Sierra Critical Zone, Sierra Transect, Ponderosa Pine Forest, Soaproot Saddle

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

Goulden, Michael

This is the AmeriFlux version of the carbon flux data for the site US-CZ2 Sierra Critical Zone, Sierra Transect, Ponderosa Pine Forest, Soaproot Saddle. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is an oak/pine forest, with occasional thinning and wildfire, a prescribed understory burn ~2012, and severe drought and ~80% canopy mortality in 2011-15

Fate of leaf-litter N in forest and grassland along a pedo-climatic gradient in south-western Siberia: an in situ 15N-labelling experiment

NASA Astrophysics Data System (ADS)

Brédoire, Félix; Zeller, Bernd; Nikitich, Polina; Barsukov, Pavel A.; Rusalimova, Olga; Bakker, Mark R.; Legout, Arnaud; Bashuk, Alexander; Kayler, Zachary E.; Derrien, Delphine

2017-04-01

The suitability of Siberia for agriculture is expected to increase in the next decades due to strong and rapid climatic changes, but little is known on the environmental drivers of soil fertility there, especially nitrogen (N). Plant-available N is mainly derived from litter decomposition. South-western (SW) Siberia is located on the transition between several bioclimatic zones that are predicted to shift and extend along with climate change (steppe, forest-steppe, sub-taiga). The soils of this region are formed on a common loess deposit but they are submitted to different climatic conditions and vegetation cover. In the south of the region, typically in steppe/forest-steppe, soil freezes over winter because of a relatively shallow snow-pack, and water shortages are frequent in summer. In the north, typically in sub-taiga, the soil is barely frozen in winter due to a thick snow-pack and sufficient soil moisture in summer. In this study, we characterized the dynamics of leaf litter decomposition and the transfer of N from leaf litter to the soil and back to plants. Four sites were chosen along a climate gradient (temperature, precipitation and snow depth). At each site, we applied 15N-labelled leaf litter on the soil surface in experimental plots in an aspen (Populus tremula L.) forest and in a grassland. Twice a year during three years, we tracked the 15N derived from the decomposing labelled-litter in the organic layers, in the first 15 cm of the soil, and in above-ground vegetation. Soil temperature and moisture were monitored at a daily timestep over three years and soil water budgets were simulated (BILJOU model, Granier et al. 1999). We observed contrasting patterns in the fate of litter-derived 15N between bioclimatic zones. Over three years, along with faster decay rates, the release of leaf litter-N was faster in sub-taiga than in forest-steppe. As such, higher quantities of 15N were transferred into the soil in sub-taiga. The transfer was also deeper there, which might be related to a more intense drainage because of higher snow levels, as inferred from soil water budget modelling. Interestingly, this higher drainage seems to induce only a small loss of N from the system. Such retention could result from soil physico-chemical properties (higher fine silt and oxides contents) enhancing soil organic matter stabilization, and/or by the immobilization of N in microbial metabolites. We observed differing N dynamics between forest and grassland that can be related to the different chemical composition of initial litter (tree leaves vs. grasses) and plant-soil interactions. In general, N was retained in the first centimeters of the mineral soil in grassland while the transfer was deeper in the forest soils. As fine root exploration is denser in grassland topsoil than in forest topsoil, we infer that an efficient uptake of N by grasses in the first soil layers limits N migration down the profile. It is also possible that grasses are active earlier in the season than trees and understorey species, i.e. at snow-melt when drainage is the most intense.

[Assessment on the changing conditions of ecosystems in key ecological function zones in China].

PubMed

Huang, Lin; Cao, Wei; Wu, Dan; Gong, Guo-li; Zhao, Guo-song

2015-09-01

In this paper, the dynamics of ecosystem macrostructure, qualities and core services during 2000 and 2010 were analyzed for the key ecological function zones of China, which were classified into four types of water conservation, soil conservation, wind prevention and sand fixation, and biodiversity maintenance. In the water conservation ecological function zones, the areas of forest and grassland ecosystems were decreased whereas water bodies and wetland were increased in the past 11 years, and the water conservation volume of forest, grassland and wetland ecosystems increased by 2.9%. This region needs to reverse the decreasing trends of forest and grassland ecosystems. In the soil conservation ecological function zones, the area of farmland ecosystem was decreased, and the areas of forest, grassland, water bodies and wetland ecosystems were increased. The total amount of the soil erosion was reduced by 28.2%, however, the soil conservation amount of ecosystems increased by 38.1%. In the wind prevention and sand fixation ecological function zones, the areas of grassland, water bodies and wetland ecosystems were decreased, but forest and farmland ecosystems were increased. The unit amount of the soil. wind erosion was reduced and the sand fixation amount of ecosystems increased lightly. In this kind of region that is located in arid and semiarid areas, ecological conservation needs to reduce farmland area and give priority to the protection of the original ecological system. In the biodiversity maintenance ecological function zones, the areas of grassland and desert ecosystems were decreased and other types were increased. The human disturbances showed a weakly upward trend and needs to be reduced. The key ecological function zones should be aimed at the core services and the protecting objects, to assess quantitatively on the effectiveness of ecosystem conservation and improvement.

Diversity and spatial structure of belowground plant-fungal symbiosis in a mixed subtropical forest of ectomycorrhizal and arbuscular mycorrhizal plants.

PubMed

Toju, Hirokazu; Sato, Hirotoshi; Tanabe, Akifumi S

2014-01-01

Plant-mycorrhizal fungal interactions are ubiquitous in forest ecosystems. While ectomycorrhizal plants and their fungi generally dominate temperate forests, arbuscular mycorrhizal symbiosis is common in the tropics. In subtropical regions, however, ectomycorrhizal and arbuscular mycorrhizal plants co-occur at comparable abundances in single forests, presumably generating complex community structures of root-associated fungi. To reveal root-associated fungal community structure in a mixed forest of ectomycorrhizal and arbuscular mycorrhizal plants, we conducted a massively-parallel pyrosequencing analysis, targeting fungi in the roots of 36 plant species that co-occur in a subtropical forest. In total, 580 fungal operational taxonomic units were detected, of which 132 and 58 were probably ectomycorrhizal and arbuscular mycorrhizal, respectively. As expected, the composition of fungal symbionts differed between fagaceous (ectomycorrhizal) and non-fagaceous (possibly arbuscular mycorrhizal) plants. However, non-fagaceous plants were associated with not only arbuscular mycorrhizal fungi but also several clades of ectomycorrhizal (e.g., Russula) and root-endophytic ascomycete fungi. Many of the ectomycorrhizal and root-endophytic fungi were detected from both fagaceous and non-fagaceous plants in the community. Interestingly, ectomycorrhizal and arbuscular mycorrhizal fungi were concurrently detected from tiny root fragments of non-fagaceous plants. The plant-fungal associations in the forest were spatially structured, and non-fagaceous plant roots hosted ectomycorrhizal fungi more often in the proximity of ectomycorrhizal plant roots. Overall, this study suggests that belowground plant-fungal symbiosis in subtropical forests is complex in that it includes "non-typical" plant-fungal combinations (e.g., ectomycorrhizal fungi on possibly arbuscular mycorrhizal plants) that do not fall within the conventional classification of mycorrhizal symbioses, and in that associations with multiple functional (or phylogenetic) groups of fungi are ubiquitous among plants. Moreover, ectomycorrhizal fungal symbionts of fagaceous plants may "invade" the roots of neighboring non-fagaceous plants, potentially influencing the interactions between non-fagaceous plants and their arbuscular-mycorrhizal fungal symbionts at a fine spatial scale.

Holocene Vegetation and Fire Dynamics for Ecosystem Management in the Spruce-Moss Domain in Northwestern Québec

NASA Astrophysics Data System (ADS)

Andy, H.; Blarquez, O.; Grondin, P.

2017-12-01

Facing the depletion of the wood resource in Québec and possible threats such as climate change, actors of the forest sector urge the need for a scientific frame to the forest management. A set of reference conditions has been developed for defining management targets that will help to keep forests within their natural range of variability according to the preindustrial period (XIX-XX centuries). Those reference conditions are based on the stands age-class distribution under a given fire regime that enable to define the percentage of old-growth forest (>100 years) to be maintained in a landscape. For the western spruce-moss domain in Québec, the fire return interval (FRI) is equal to 150 years resulting in a target of 48% of old-growth forests. Yet, this target supposes that the environment and the ecosystem processes are homogeneous for an entire bioclimatic domain of 175 000 km2. By using a Redundancy Analysis (RDA) on modern inventories data on natural and human disturbances; climate and physical variables and forest composition, we were able to distinguish 5 main zones where interactions between stands and their environment are homogeneous and where local management targets could be developed. We then used 10 published sedimentary pollens and charcoal series in order to reconstruct the holocene fire and vegetation dynamics for those zones. Vegetation deduced from the analysis of the pollen diagrams showed that the long-term vegetation dynamics are zone specific indicating that the modern forest composition is a result of the Holocene trajectories occurring within each zone. Charcoals series were statistically analyzed for past fire detection and long-term FRI reconstruction. They suggest that for the entire territory the holocene FRI range from 174 to 265 years resulting in old-growth forests percentage within 44 and 65% depending on the zone. Hence, we conclude that current management targets should be revised to fit more with local forests ecosystem variability at the landscape scale and that reference condition should be supplemented with data on the long-term fire dynamics and forest composition variability.

Dominant forest tree mycorrhizal type mediates understory plant invasions

Treesearch

Insu Jo; Kevin M. Potter; Grant M. Domke; Songlin Fei

2017-01-01

Forest mycorrhizal type mediates nutrient dynamics, which in turn can influence forest community structure and processes. Using forest inventory data, we explored how dominant forest tree mycorrhizal type affects understory plant invasions with consideration of forest structure and soil properties. We found that arbuscular mycorrhizal (AM) dominant forests, which are...

Using classified Landsat Thematic Mapper data for stratification in a statewide forest inventory

Treesearch

Mark H. Hansen; Daniel G. Wendt

2000-01-01

The 1998 Indiana/Illinois forest inventory (USDA Forest Service, Forest Inventory and Analysis (FIA)) used Landsat Thematic Mapper (TM) data for stratification. Classified images made by the National Gap Analysis Program (GAP) stratified FIA plots into four classes (nonforest, nonforest/ forest, forest/nonforest, and forest) based on a two pixel forest edge buffer zone...

Using Classified Landsat Thematic Mapper Data for Stratification in a Statewide Forest Inventory

Treesearch

Mark H. Hansen; Daniel G. Wendt

2000-01-01

The 1998 Indiana/Illinois forest inventory (USDA Forest Service, Forest Inventory and Analysis (FIA)) used Landsat Thematic Mapper (TM} data for stratification. Classified images made by the National Gap Analysis Program (GAP) stratified FIA plots into four classes (nonforest, nonforest/forest, forest/nonforest, and forest) based on a two pixel forest edge buffer zone...

Application of remote sensing and geographical information system in mapping forest fire risk zone at Bhadra wildlife sanctuary, India.

PubMed

Sowmya, S V; Somashekar, R K

2010-11-01

Fire is the most spectacular natural disturbance that affects the forest ecosystem composition and diversity. Fire has a devastating effect on the landscape and its impact is felt at every level of the ecosystem and it is possible to map forest fire risk zone and thereby minimize the frequency of fire. There is a need for supranational approaches that analyze wide scenarios of factors involved and global fire effects. Fires can be monitored and analyzed over large areas in a timely and cost effective manner by using satellite imagery. Also Geographical Information System (GIS) can be used effectively to demarcate the fire risk zone map. Bhadra wildlife Sanctuary located in Kamataka, India was selected for this study. Vegetation, slope, distance from roads, settlements parameters were derived for a study area using topographic maps and field information. The Remote Sensing (RS) and Geographical Information System (GIS)-based forest fire risk model of the study area appeared to be highly compatible with the actual fire-affected sites. The temporal satellite data from 1989 to2006 have been analyzed to map the burnt areas. These classes were weighted according to their influence on forest fire. Four categories of fire risk regions such as Low, Moderate, High and Very high fire intensity zones were identified. It is predicted that around 10.31% of the area falls undermoderate risk zone.

Influence of Forest Management Regimes on Forest Dynamics in the Upstream Region of the Hun River in Northeastern China

PubMed Central

Yao, Jing; He, Xingyuan; Wang, Anzhi; Chen, Wei; Li, Xiaoyu; Lewis, Bernard J.; Lv, Xiaotao

2012-01-01

Balancing forest harvesting and restoration is critical for forest ecosystem management. In this study, we used LANDIS, a spatially explicit forest landscape model, to evaluate the effects of 21 alternative forest management initiatives which were drafted for forests in the upstream region of the Hun River in northeastern China. These management initiatives included a wide range of planting and harvest intensities for Pinus koraiensis, the historically dominant tree species in the region. Multivariate analysis of variance, Shannon's Diversity Index, and planting efficiency (which indicates how many cells of the target species at the final year benefit from per-cell of the planting trees) estimates were used as indicators to analyze the effects of planting and harvesting regimes on forests in the region. The results showed that the following: (1) Increased planting intensity, although augmenting the coverage of P. koraiensis, was accompanied by decreases in planting efficiency and forest diversity. (2) While selective harvesting could increase forest diversity, the abrupt increase of early succession species accompanying this method merits attention. (3) Stimulating rapid forest succession may not be a good management strategy, since the climax species would crowd out other species which are likely more adapted to future climatic conditions in the long run. In light of the above, we suggest a combination of 30% planting intensity with selective harvesting of 50% and 70% of primary and secondary timber species, respectively, as the most effective management regime in this area. In the long run this would accelerate the ultimate dominance of P. koraiensis in the forest via a more effective rate of planting, while maintaining a higher degree of forest diversity. These results are particularly useful for forest managers constrained by limited financial and labor resources who must deal with conflicts between forest harvesting and restoration. PMID:22723930

Impacts of fire on non-native plant recruitment in black spruce forests of interior Alaska.

PubMed

Walker, Xanthe J; Frey, Matthew D; Conway, Alexandra J; Jean, Mélanie; Johnstone, Jill F

2017-01-01

Climate change is expected to increase the extent and severity of wildfires throughout the boreal forest. Historically, black spruce (Picea mariana (Mill.) B.S.P.) forests in interior Alaska have been relatively free of non-native species, but the compounding effects of climate change and an altered fire regime could facilitate the expansion of non-native plants. We tested the effects of wildfire on non-native plant colonization by conducting a seeding experiment of non-native plants on different substrate types in a burned black spruce forest, and surveying for non-native plants in recently burned and mature black spruce forests. We found few non-native plants in burned or mature forests, despite their high roadside presence, although invasion of some burned sites by dandelion (Taraxacum officinale) indicated the potential for non-native plants to move into burned forest. Experimental germination rates were significantly higher on mineral soil compared to organic soil, indicating that severe fires that combust much of the organic layer could increase the potential for non-native plant colonization. We conclude that fire disturbances that remove the organic layer could facilitate the invasion of non-native plants providing there is a viable seed source and dispersal vector.

Forecasts of forest conditions

Treesearch

Robert Huggett; David N. Wear; Ruhong Li; John Coulston; Shan Liu

2013-01-01

Key FindingsAmong the five forest management types, only planted pine is expected to increase in area. In 2010 planted pine comprised 19 percent of southern forests. By 2060, planted pine is forecasted to comprise somewhere between 24 and 36 percent of forest area.Although predicted rates of change vary, all forecasts reveal...

Canopy reflectance modeling in a tropical wooded grassland

NASA Technical Reports Server (NTRS)

Simonett, David; Franklin, Janet

1986-01-01

Geometric/optical canopy reflectance modeling and spatial/spectral pattern recognition is used to study the form and structure of savanna in West Africa. An invertible plant canopy reflectance model is tested for its ability to estimate the amount of woody vegetation from remotely sensed data in areas of sparsely wooded grassland. Dry woodlands and wooded grasslands, commonly referred to as savannas, are important ecologically and economically in Africa, and cover approximately forty percent of the continent by some estimates. The Sahel and Sudan savannas make up the important and sensitive transition zone between the tropical forests and the arid Sahara region. The depletion of woody cover, used for fodder and fuel in these regions, has become a very severe problem for the people living there. LANDSAT Thematic Mapper (TM) data is used to stratify woodland and wooded grassland into areas of relatively homogeneous canopy cover, and then an invertible forest canopy reflectance model is applied to estimate directly the height and spacing of the trees in the stands. Because height and spacing are proportional to biomass in some cases, a successful application of the segmentation/modeling techniques will allow direct estimation of tree biomass, as well as cover density, over significant areas of these valuable and sensitive ecosystems. The model being tested in sites in two different bioclimatic zones in Mali, West Africa, will be used for testing the canopy model. Sudanian zone crop/woodland test sites were located in the Region of Segou, Mali.

Analysis of growth trend changes for 51 temperate tree species using Korea national forest inventory data

NASA Astrophysics Data System (ADS)

Park, M.; Moon, M.; Park, J.; Cho, S.; Kim, H. S.

2016-12-01

Individual tree growth rates can be affected by various factors such as species, soil fertility, stand development stage, disturbance, and climate etc. To estimate the effect of changes in tree growth rate on the structure and functionality of forest ecosystem in the future, we analyzed the change of species-specific growth trends using the fifth Korea national forest inventory data, which was collected from 2006 to 2010. The ring samples of average tree were collected from nationwide inventory plots and the total number of individual tree ring series was 69,128 covering 185 tree species. Among those, fifty one species with more than 100 tree ring series were used for our analysis. For growth-trend analysis, standardized regional curves of individual species growth were generated from three forest zone in South Korea; subarctic, cool temperate, warm temperate forest zone. Then individual tree ring series was indexed by dividing the growth of the tree by expected growth from standardized regional curves. Then the ratio of all tree ring series were aligned by year and the Spearman's correlation coefficient of each species was calculated. The results show that most of species had increasing growth rates as forests developed after Korean war. For the last thirty years, 67.3% of species including Quercus spp. and Zelkova serrata had positive growth trends, on the other hand, 11.5% of species including Pinus spp. showed negative growth trends probably due to the changes in successional stages in Korean forests and climate change. These trends also vary with climate zone and species. For examples, Pinus densiflora, which showed negative growth trend overall, had steep negative growth trends in boreal and temperate zone, whereas it showed no specific trend in sub-tropical climate zone. Our trend analysis on 51 temperate tree species growth will be essential to predict the temperate forests species change for the this century.

Changes in carbon pool and stand structure of a native subtropical mangrove forest after inter-planting with exotic species Sonneratia apetala.

PubMed

Lu, Weizhi; Yang, Shengchang; Chen, Luzhen; Wang, Wenqing; Du, Xiaona; Wang, Canmou; Ma, Yan; Lin, Guangxuan; Lin, Guanghui

2014-01-01

In this study, we compared stand structure, biomass and soil carbon pools, and litterfall production between a mixed mangrove forest consisting of Aegiceras corniculatum inter-planted with the exotic Sonneratia apetala and a native monospecific forest dominated by A. corniculatum in the intertidal area of Zhanjiang, Guangdong Province, southeast China. The goal of this study was to test the hypothesis that inter-planting fast growing exotic mangrove S. apetala into subtropical native mangrove forests will significantly increase C sequestration. Although the tree heights and basal diameters of S. apetala were significantly higher than those of A. corniculatum, the density of the 12-year-old S. apetala trees in the mixed forest was much smaller than that of A. corniculatum in the monospecific forest. In contrast to several previous studies on S. apetala forests planted directly on mangrove-free mudflats, the mixed mangrove forest showed no significant difference in either standing biomass or soil carbon pools from the native monospecific mangrove forest (p = 0.294 and 0.073, respectively) twelve years after inter-planting with S. apetala. Moreover, carbon cycling was likely speeded up after inter-planting S. apetala due to higher litterfall input and lower C/N ratio. Thus, inter-planting fast-growing S. apetala into native mangrove forest is not an effective way to increase carbon sequestration in this subtropical mangrove forest. Given that exotic plant species may exert negative impact on native mangrove species and related epifauna, this fast-growing mangrove species is not suitable for mangrove plantation projects aiming mainly at enhancing carbon sequestration.

36 CFR 13.1304 - Ice fall hazard zones.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Ice fall hazard zones. 13.1304 Section 13.1304 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park General...

Regeneration of native California oaks in the forest zone [Abstract

Treesearch

P.M. McDonald

1999-01-01

The two native California oaks in the forest zone of California are California black oak (Quercus kelloggii Newb.) and tanoak (Lithocarpus densiflorus [Hook. and Arn.] Rehd.). Both are ancient species with many adaptations to withstand California's Mediterranean climate, but some weaknesses as well. Both sprout vigorously...

Development of a national forest inventory for carbon accounting purposes in New Zealand's planted Kyoto forests

Treesearch

John Moore; Ian Payton; Larry Burrows; Chris Goulding; Peter Beets; Paul Lane; Peter Stephens

2007-01-01

This article discusses the development of a monitoring system to estimate carbon sequestration in New Zealand's planted Kyoto forests, those forests that have been planted since January 1, 1990, on land that previously did not contain forest. The system must meet the Intergovernmental Panel on Climate Change good practice guidance and must be seen to be unbiased,...

Plant and bird diversity in natural forests and in native and exotic plantations in NW Portugal

NASA Astrophysics Data System (ADS)

Proença, Vânia M.; Pereira, Henrique M.; Guilherme, João; Vicente, Luís

2010-03-01

Forest ecosystems have been subjected to continuous dynamics between deforestation and forestation. Assessing the effects of these processes on biodiversity could be essential for conservation planning. We analyzed patterns of species richness, diversity and evenness of plants and birds in patches of natural forest of Quercus spp. and in stands of native Pinus pinaster and exotic Eucalyptus globulus in NW Portugal. We analyzed data of forest and non-forest species separately, at the intra-patch, patch and inter-patch scales. Forest plant richness, diversity and evenness were higher in oak forest than in pine and eucalypt plantations. In total, 52 species of forest plants were observed in oak forest, 33 in pine plantation and 28 in eucalypt plantation. Some forest species, such as Euphorbia dulcis, Omphalodes nitida and Eryngium juresianum, were exclusively or mostly observed in oak forest. Forest bird richness and diversity were higher in both oak and pine forests than in eucalypt forest; evenness did not differ among forests. In total, 16 species of forest birds were observed in oak forest, 18 in pine forest and 11 in eucalypt forest. Species such as Certhia brachydactyla, Sitta europaea and Dendrocopos major were common in oak and/or pine patches but were absent from eucalypt stands. Species-area relationships of forest plants and forest birds in oak patches had consistently a higher slope, at both the intra and inter-patch scales, than species-area relationships of forest species in plantations and non-forest species in oak forest. These findings demonstrate the importance of oak forest for the conservation of forest species diversity, pointing the need to conserve large areas of oak forest due to the apparent vulnerability of forest species to area loss. Additionally, diversity patterns in pine forest were intermediate between oak forest and eucalypt forest, suggesting that forest species patterns may be affected by forest naturalness.

Dominant forest tree mycorrhizal type mediates understory plant invasions

Treesearch

Insu Jo; Kevin M. Potter; Grant M. Domke; Songlin Fei

2018-01-01

Forest mycorrhizal type mediates nutrient dynamics, which in turn can influence forest community structure and processes. Using forest inventory data, we explored how dominant forest tree myc- orrhizal type affects understory plant invasions with consideration of forest structure and soil properties. We found that arbuscular mycorrhizal (AM) dominant forests, which are...

Robustness of plant-insect herbivore interaction networks to climate change in a fragmented temperate forest landscape.

PubMed

Bähner, K W; Zweig, K A; Leal, I R; Wirth, R

2017-10-01

Forest fragmentation and climate change are among the most severe and pervasive forms of human impact. Yet, their combined effects on plant-insect herbivore interaction networks, essential components of forest ecosystems with respect to biodiversity and functioning, are still poorly investigated, particularly in temperate forests. We addressed this issue by analysing plant-insect herbivore networks (PIHNs) from understories of three managed beech forest habitats: small forest fragments (2.2-145 ha), forest edges and forest interior areas within three continuous control forests (1050-5600 ha) in an old hyper-fragmented forest landscape in SW Germany. We assessed the impact of forest fragmentation, particularly edge effects, on PIHNs and the resulting differences in robustness against climate change by habitat-wise comparison of network topology and biologically realistic extinction cascades of networks following scores of vulnerability to climate change for the food plant species involved. Both the topological network metrics (complexity, nestedness, trophic niche redundancy) and robustness to climate change strongly increased in forest edges and fragments as opposed to the managed forest interior. The nature of the changes indicates that human impacts modify network structure mainly via host plant availability to insect herbivores. Improved robustness of PIHNs in forest edges/small fragments to climate-driven extinction cascades was attributable to an overall higher thermotolerance across plant communities, along with positive effects of network structure. The impoverishment of PIHNs in managed forest interiors and the suggested loss of insect diversity from climate-induced co-extinction highlight the need for further research efforts focusing on adequate silvicultural and conservation approaches.

Snowpack, fire, and forest disturbance: interactions affect montane invasions by non-native shrubs.

PubMed

Stevens, Jens T; Latimer, Andrew M

2015-06-01

Montane regions worldwide have experienced relatively low plant invasion rates, a trend attributed to increased climatic severity, low rates of disturbance, and reduced propagule pressure relative to lowlands. Manipulative experiments at elevations above the invasive range of non-native species can clarify the relative contributions of these mechanisms to montane invasion resistance, yet such experiments are rare. Furthermore, global climate change and land use changes are expected to cause decreases in snowpack and increases in disturbance by fire and forest thinning in montane forests. We examined the importance of these factors in limiting montane invasions using a field transplant experiment above the invasive range of two non-native lowland shrubs, Scotch broom (Cytisus scoparius) and Spanish broom (Spartium junceum), in the rain-snow transition zone of the Sierra Nevada of California. We tested the effects of canopy closure, prescribed fire, and winter snow depth on demographic transitions of each species. Establishment of both species was most likely at intermediate levels of canopy disturbance, but at this intermediate canopy level, snow depth had negative effects on winter survival of seedlings. We used matrix population models to show that an 86% reduction in winter snowfall would cause a 2.8-fold increase in population growth rates in Scotch broom and a 3.5-fold increase in Spanish broom. Fall prescribed fire increased germination rates, but decreased overall population growth rates by reducing plant survival. However, at longer fire return intervals, population recovery between fires is likely to keep growth rates high, especially under low snowpack conditions. Many treatment combinations had positive growth rates despite being above the current invasive range, indicating that propagule pressure, disturbance, and climate can all strongly affect plant invasions in montane regions. We conclude that projected reductions in winter snowpack and increases in forest disturbance are likely to increase the risk of invasion from lower elevations. © 2014 John Wiley & Sons Ltd.

Influence of Diffuse Radiation and Its Timescale Effects on Gross Primary Productivity in a Mid-subtropical Planted Coniferous Forest Ecosystem.

NASA Astrophysics Data System (ADS)

Han, J.; Zhang, L.; Li, S.

2017-12-01

The mid-subtropical forests in East Asia monsoon zone act as an important carbon sink. Planted coniferous forests are important vegetation types in this area. However, we lack an in-depth understanding of both controlling mechanisms of environmental and biotic factors in gross primary productivity (GPP) and their timescale effects. Based on eddy covariance carbon flux data and micro-meteorological data (2003-2015) observed at a mid-subtropical planted coniferous forest in Qianyanzhou, along with leaf area index derived from MODIS products, we used the path analysis mothed to quantify standardized total effects (STE) of environmental factors on GPP and their variabilities at different timescales. We found that GPP was mainly affected by photosynthetically active radiation (PAR) at half-hour scale. Furthermore, GPP under cloudy weather conditions was greater than under sunny weather conditions across seasons. From daily to yearly scales, PAR had the positive STE with GPP, but such STE was gradually reduced toward yearly scale; diffuse radiation or air temperature had the positive STE with GPP at daily and monthly scales, while negative STE occurred at seasonal and yearly scales. Vapor pressure deficit exhibited the negative STE with GPP at all timescales, and such STE increased gradually toward the yearly scale. Therefore, on one hand, GPP was controlled by light conditions, but on the other hand, high air temperature in summer and water availability had a significant restraining effect over GPP, and such effect increased with the timescales from day to year. Based on the simulation results by the light use efficiency (LUE) model, it indicated that modelled GPP agreed well with the measurements when the influence of the seasonal variations of LUE and diffuse radiation were incorporated into the model, especially at the yearly scale. This further indicated that diffuse radiation, together with changes in air temperature and water supply, had a significant effect on the variations of yearly GPP.

Impact of Scots pine (Pinus sylvestris L.) plantings on long term (137)Cs and (90)Sr recycling from a waste burial site in the Chernobyl Red Forest.

PubMed

Thiry, Yves; Colle, Claude; Yoschenko, Vasyl; Levchuk, Svjatoslav; Van Hees, May; Hurtevent, Pierre; Kashparov, Valery

2009-12-01

Plantings of Scots pine (Pinus sylvestris L.) on a waste burial site in the Chernobyl Red Forest was shown to greatly influence the long term redistribution of radioactivity contained in sub-surfaces trenches. After 15 years of growth, aboveground biomass of the average tree growing on waste trench no.22 had accumulated 1.7 times more (137)Cs than that of trees growing off the trench, and 5.4 times more (90)Sr. At the scale of the trench and according to an average tree density of 3300 trees/ha for the study zone, tree contamination would correspond to 0.024% of the (137)Cs and 2.52% of the (90)Sr contained in the buried waste material. A quantitative description of the radionuclide cycling showed a potential for trees to annually extract up to 0.82% of the (90)Sr pool in the trench and 0.0038% of the (137)Cs. A preferential (90)Sr uptake from the deep soil is envisioned while pine roots would take up (137)Cs mostly from less contaminated shallow soil layers. The current upward flux of (90)Sr through vegetation appeared at least equal to downward loss in waste material leaching as reported by Dewiere et al. (2004, Journal of Environmental Radioactivity 74, 139-150). Using a prospective calculation model, we estimated that maximum (90)Sr cycling can be expected to occur at 40 years post-planting, resulting in 12% of the current (90)Sr content in the trench transferred to surface soils through biomass turnover and 7% stored in tree biomass. These results are preliminary, although based on accurate methodology. A more integrated ecosystem study leading to the coupling between biological and geochemical models of radionuclide cycling within the Red Forest seems opportune. Such a study would help in the adequate management of that new forest and the waste trenches upon which they reside.

Dry Season Rainfall Anomalies due to Deforestation in Northern Mesoamerica: Implications for Forest Sustainability

NASA Astrophysics Data System (ADS)

Welch, R. M.; Ray, D. K.; Lawton, R. O.; Nair, U.

2005-12-01

In the region stretching between Mexico and Panama, the proposed Mesoamerican Biological Corridor (MBC) is an ambitious effort to stem and turn back the erosion of biodiversity in one of the world's biologically richest regions by connecting large existing parks and reserves with new protected areas by means of an extensive network of biological corridors. The success of this effort will depend in part on the ability of the connecting corridors to provide adequate habitats permitting the sustainability of some populations and the migratory movements of others. Ideally these connecting corridors would contain the biological communities which were originally present. Currently, however, many of these connecting corridors do not contain their original forest, but are instead occupied by agricultural landscapes containing croplands, grasslands and degraded woodlands. The forest types in northern Mesoamerica generally are those that require dry season rainfall for their survival, and it is not clear whether current environmental and climatological conditions are sufficient to maintain existing forests and regenerate the pristine forests in the deforested patches. Hourly climatological rainfall rates have been averaged for the time period of 1961 to 1997 at 266 stations in Guatemala and adjacent areas. These climatological rainfall rates have been segregated for forested and deforested regions of each of the major Holdridge life zones. Dry season cloud frequency of occurrences derived from GOES satellite imagery then are. correlated with the March climalogical data in order to generate regression estimates of current local rainfall. Differences between estimated current rainfall and historical values define regions under increased dry season water stress. In general dry season rainfall in March is markedly lower in deforested areas than in forested areas of the same life zone for most of the Holdridge life zones. In some deforested areas within the Holdridge wet forest life zones, estimated March rainfall deficits are >25 mm. Dry season deforested habitats tend to have higher daytime temperatures, are less cloudy, have lower estimated soil moisture and lower values of Normalized Difference Vegetation Index (NDVI) than do forested habitats in the same life zone. The result is hotter and drier air over deforested regions, with lower values of cloud formation and precipitation. The data suggest that deforestation is locally intensifying the dry season and increasing the risk of fire, especially for the long corridor connecting regions. In addition, forest regeneration in some parts of the MBC may not result in second-growth forest that is characteristic of that life zone but rather in forest regeneration more typical of drier conditions. The extent to which this would influence the conservation utility of any given corridor depends upon the ecological requirements of the organisms concerned.

Exotic invasive plants in southeastern forests

Treesearch

James H. Miller

1998-01-01

Invasive exotic plants usurp forest productivity, hinder forest-use activities, and limit diversity on millions of acres of forest land in the Southeast Infestations of these plants and their range are constantly expanding, This paper examines the various aspects of the problem. Outlined are the biology, origin, range, uses, and herbicide control for 14 of the most...

Inventory shows extent of non-native invasive plants in Minnesota forests

Treesearch

W. Keith Moser; Mark D. Nelson; Mark H. Hansen

2009-01-01

Readers are no doubt aware of the impact that non-native invasive plants (NNIP) present to Minnesota's ecosystems. The U.S. Forest Service's Northern Research Station (NRS) Forest Inventory and Analysis (FIA) Program is studying what determines where these plants are found, including forest type, tree density, disturbance, productivity, and topography.

Forest condition in Latvia

Treesearch

Madis Sipols

1998-01-01

Systematic assessment and observation (survey, inventory) of forests in Latvia has been underway since the 1700's. Latvia's forests are in the boreal/temperate forest zone and cover 44 percent of the country. Forest growing conditions are subdivided into five site class types: forests on dry mineral, wet mineral, wet peat, drained mineral, drained peat soils...

Do forest soil microbes have the potential to resist plant invasion? A case study in Dinghushan Biosphere Reserve (South China)

NASA Astrophysics Data System (ADS)

Chen, Bao-Ming; Li, Song; Liao, Hui-Xuan; Peng, Shao-Lin

2017-05-01

Successful invaders must overcome biotic resistance, which is defined as the reduction in invasion success caused by the resident community. Soil microbes are an important source of community resistance to plant invasions, and understanding their role in this process requires urgent investigation. Therefore, three forest communities along successional stages and four exotic invasive plant species were selected to test the role of soil microbes of three forest communities in resisting the exotic invasive plant. Our results showed that soil microbes from a monsoon evergreen broadleaf forest (MEBF) (late-successional stage) had the greatest resistance to the invasive plants. Only the invasive species Ipomoea triloba was not sensitive to the three successional forest soils. Mycorrhizal fungi in early successional forest Pinus massonina forest (PMF) or mid-successional forest pine-broadleaf mixed forest (PBMF) soil promoted the growth of Mikania micrantha and Eupatorium catarium, but mycorrhizal fungi in MEBF soil had no significant effects on their growth. Pathogens plus other non-mycorrhizal microbes in MEBF soil inhibited the growth of M. micrantha and E. catarium significantly, and only inhibited root growth of E. catarium when compared with those with mycorrhizal fungi addition. The study suggest that soil mycorrhizal fungi of early-mid-successional forests benefit invasive species M. micrantha and E. catarium, while soil pathogens of late-successional forest may play an important role in resisting M. micrantha and E. catarium. The benefit and resistance of the soil microbes are dependent on invasive species and related to forest succession. The study gives a possible clue to control invasive plants by regulating soil microbes of forest community to resist plant invasion.

Non-native plant invasions in managed and protected ponderosa pine/douglas-fir forests of the Colorado Front Range

USGS Publications Warehouse

Fornwalt, P.J.; Kaufmann, M.R.; Huckaby, L.S.; Stoker, J.M.; Stohlgren, T.J.

2003-01-01

We examined patterns of non-native plant diversity in protected and managed ponderosa pine/Douglas-fir forests of the Colorado Front Range. Cheesman Lake, a protected landscape, and Turkey Creek, a managed landscape, appear to have had similar natural disturbance histories prior to European settlement and fire protection during the last century. However, Turkey Creek has experienced logging, grazing, prescribed burning, and recreation since the late 1800s, while Cheesman Lake has not.Using the modified-Whittaker plot design to sample understory species richness and cover, we collected data for 30 0.1 ha plots in each landscape. Topographic position greatly influenced results, while management history did not. At both Cheesman Lake and Turkey Creek, low/riparian plots had highest native and non-native species richness and cover; upland plots (especially east/west-facing, south-facing and flat, high plots) had the lowest. However, there were no significant differences between Cheesman Lake and Turkey Creek for native species richness, native species cover, non-native species richness, or non-native species cover for any topographic category. In general, non-native species richness and cover were highly positively correlated with native species richness and/or cover (among other variables). In total, 16 non-native species were recorded at Cheesman Lake and Turkey Creek; none of the 16 non-native species were more common at one site than another.These findings suggest that: (1) areas that are high in native species diversity also contain more non-native species; (2) both protected and managed areas can be invaded by non-native plant species, and at similar intensities; and (3) logging, grazing, and other similar disturbances may have less of an impact on non-native species establishment and growth than topographic position (i.e., in lowland and riparian zones versus upland zones).

Non-native plant invasions in managed and protected ponderosa pine/Douglas-fir forests of the Colorado Front Range

USGS Publications Warehouse

Fornwalt, P.J.; Kaufmann, M.R.; Huckaby, L.S.; Stoker, J.M.; Stohlgren, T.J.

2003-01-01

We examined patterns of non-native plant diversity in protected and managed ponderosa pine/Douglas-fir forests of the Colorado Front Range. Cheesman Lake, a protected landscape, and Turkey Creek, a managed landscape, appear to have had similar natural disturbance histories prior to European settlement and fire protection during the last century. However, Turkey Creek has experienced logging, grazing, prescribed burning, and recreation since the late 1800s, while Cheesman Lake has not. Using the modified-Whittaker plot design to sample understory species richness and cover, we collected data for 30 0.1 ha plots in each landscape. Topographic position greatly influenced results, while management history did not. At both Cheesman Lake and Turkey Creek, low/riparian plots had highest native and non-native species richness and cover; upland plots (especially east/west-facing, south-facing and flat, high plots) had the lowest. However, there were no significant differences between Cheesman Lake and Turkey Creek for native species richness, native species cover, non-native species richness, or non-native species cover for any topographic category. In general, non-native species richness and cover were highly positively correlated with native species richness and/or cover (among other variables). In total, 16 non-native species were recorded at Cheesman Lake and Turkey Creek; none of the 16 non-native species were more common at one site than another. These findings suggest that: (1) areas that are high in native species diversity also contain more non-native species; (2) both protected and managed areas can be invaded by non-native plant species, and at similar intensities; and (3) logging, grazing, and other similar disturbances may have less of an impact on non-native species establishment and growth than topographic position (i.e., in lowland and riparian zones versus upland zones).

Contrasting Taxonomic and Phylogenetic Diversity Responses to Forest Modifications: Comparisons of Taxa and Successive Plant Life Stages in South African Scarp Forest

PubMed Central

Grass, Ingo; Brandl, Roland; Botzat, Alexandra; Neuschulz, Eike Lena; Farwig, Nina

2015-01-01

The degradation of natural forests to modified forests threatens subtropical and tropical biodiversity worldwide. Yet, species responses to forest modification vary considerably. Furthermore, effects of forest modification can differ, whether with respect to diversity components (taxonomic or phylogenetic) or to local (α-diversity) and regional (β-diversity) spatial scales. This real-world complexity has so far hampered our understanding of subtropical and tropical biodiversity patterns in human-modified forest landscapes. In a subtropical South African forest landscape, we studied the responses of three successive plant life stages (adult trees, saplings, seedlings) and of birds to five different types of forest modification distinguished by the degree of within-forest disturbance and forest loss. Responses of the two taxa differed markedly. Thus, the taxonomic α-diversity of birds was negatively correlated with the diversity of all plant life stages and, contrary to plant diversity, increased with forest disturbance. Conversely, forest disturbance reduced the phylogenetic α-diversity of all plant life stages but not that of birds. Forest loss neither affected taxonomic nor phylogenetic diversity of any taxon. On the regional scale, taxonomic but not phylogenetic β-diversity of both taxa was well predicted by variation in forest disturbance and forest loss. In contrast to adult trees, the phylogenetic diversity of saplings and seedlings showed signs of contemporary environmental filtering. In conclusion, forest modification in this subtropical landscape strongly shaped both local and regional biodiversity but with contrasting outcomes. Phylogenetic diversity of plants may be more threatened than that of mobile species such as birds. The reduced phylogenetic diversity of saplings and seedlings suggests losses in biodiversity that are not visible in adult trees, potentially indicating time-lags and contemporary shifts in forest regeneration. The different responses of taxonomic and phylogenetic diversity to forest modifications imply that biodiversity conservation in this subtropical landscape requires the preservation of natural and modified forests. PMID:25719204

Ecohydrological controls of watershed response to land use change in the montane cloud forest zone in Mexico

NASA Astrophysics Data System (ADS)

Asbjornsen, H.; Alvarado-Barrientos, M. S.; Bruijnzeel, L. A.; Dawson, T. E.; Geissert, D. R.; Goldsmith, G. R.; Gomez-Cardenas, M.; Gomez-Tagle, A.; Gotsch, S.; Holwerda, F.; McDonnell, J. J.; Munoz Villers, L. E.; Tobon, C.

2012-12-01

Land use conversion and climate change threaten the hydrological services from tropical montane cloud forest (TMCFs) regions, but knowledge about the ecohydrological mechanisms controlling catchment response is limited. This project traced the hydrologic sources, fluxes and flowpaths across the atmosphere-plant-soil-stream continuum under different land cover types (degraded pasture, regenerating forest, mature forest, pine reforestation) in a seasonally dry TMCF in Veracruz, Mexico. We used hydrological (cloud water interception, CWI; streamflow) and ecophysiological measurements (transpiration, E; foliar uptake, FU) in combination with stable isotope techniques to identify the key ecohydrological processes of each land cover and quantify the hydrological effects of TMCF conversion. Results revealed that CWI was only ≤2% of total annual rainfall due to low fog occurrence and wind speeds. Fog without rainfall reduced E by a factor of 4-5 relative to sunny conditions and by a factor of 2 relative to overcast conditions, whereas the water 'gained' from the fog suppression effect was ~80-100mm year-1 relative to sunny conditions. At the canopy scale, FU resulted in the recovery of 9% of total E, suggesting a crucial role in alleviating plant water deficit; nevertheless, it was not sufficient to compensate for the 17% water loss from nighttime E. Trees primarily utilized water from 30-50cm soil depth, while water reaching the stream was derived from deep, 'old' water that was distinct from both 'new' rainwater and water accessed by plants. These findings suggest that plants mainly access a more tightly bound soil water pool that does not actively mix with the more mobile water recharging deep soil and groundwater pools. Soils had high porosity, saturated conductivity, infiltration rates, and water storage capacity, which contributed to the relatively low rainfall-runoff responses, mainly generated from deep subsurface flowpaths. Results showed that conversion of mature forest to pasture or forest regeneration on former TMCF increased annual water yield by 600mm and 300mm, respectively, while planting pine on degraded pastures reduced water yield by 365mm. Differences in water yield mainly reflect differences in rainfall interception loss. Runoff behavior was similar among land cover types, except for very high intensity storms when pasture showed higher surface runoff. Our results suggest that the ecophysiological effects of fog via suppressed E and FU has a greater impact on water yield than direct inputs from CWI in this TMCF. Rapid vertical rainfall percolation and recharge result in a largely groundwater driven system whereby streamflow dynamics is uncoupled from plant water uptake, and water storage capacity and buffering potential are exceptionally high. These factors, combined with the soil properties, resulted in reduced dry season flows due to land use conversion to pasture only being detected towards the end of the dry season. Projected lifting of the cloud base associated with regional climate change combined with declining rainfall may significantly alter ecohydrological functions of these TMCFs.

Tropical Deforestation in the Bolivian Amazon

NASA Technical Reports Server (NTRS)

Tucker, Compton J.; Steininger, Marc K.; Townshend, John R. G.; Killeen, Timothy R.; Desch, Arthur

2000-01-01

Landsat satellite images from the mid-1980s and early 1990s were used to map tropical forest extent and deforestation in approximately 800,000 sq km of Amazonian Bolivia. Forest cover extent, including tropical deciduous forest, totalled 472,000 sq km while the area of natural non-forest formations totalled 298,000 sq km. The area deforested totalled 15,000 sq km in the middle 1980s and 28,800 sq km by the early 1990s. The rate of tropical deforestation in the >1,000 mm/y precipitation forest zone of Bolivia was 2,200 sq km/y from 1985-1986 to 1992-1994. We document a spatially-concentrated "deforestation zone" in Santa Cruz Department where >60% of the Bolivian deforestation is occurring at an accelerating rate in areas of tropical deciduous dry forest.

Natural History and Ecology of Soldier Beetles (Coleoptera: Cantharidae) in the Mexican Tropical Dry Forests.

PubMed

Pérez-Hernández, Cisteil X

2018-06-06

Until today, most information about the natural history and ecology of soldier beetles came from temperate zones, mainly from Holarctic areas, while tropical regions have been poorly studied. The aim of this contribution is to compile and synthesize information concerning the natural history and ecology of Cantharidae (Coleoptera) from the Mexican tropical dry forest (TDF), to serve as a starting point for more in-depth study of the group in one of the Mexico's most endangered ecosystems. All compiled data on the family have been organized into the following topics: distributional patterns and habitat preferences, feeding behavior and host plants, and daily and seasonal activity cycles. For the first time, it was provided a list of host plants for TDF Cantharidae genera and species, and it was also observed a high ecological diversity in the phenology and behavior of TDF Cantharidae assemblages. Further research concerning cantharids and other TDF insects needs to have a more comprehensive and integrated approach toward understanding the patterns of distribution and diversity, and elucidating the role that cantharids play in ecosystems, especially in TDF, which is one of the most endangered ecosystem in the world.

Geographic distributions and ecology of ornamental Curcuma (Zingiberaceae) in Northeastern Thailand.

PubMed

Khumkratok, Sutthira; Boongtiang, Kriangsuk; Chutichudet, Prasit; Pramaul, Pairot

2012-10-01

The genus Curcuma is a very important economic plant. Members of this genus were used as food, medicine and ornament plants. The objectives of this study were to examine the geographic distributions and ecological conditions in the natural habitats of Curcuma in Northeastern Thailand. Species diversity was examined using the line transect method. Ecological conditions of the species were examined using a sampling plot of 20 x 20 m. A total of five species were found including Curcuma angustifolia Roxb., C. alismatifolia Gagnep., C. gracillima Gagnep., C. parviflora Wall. and C. rhabdota. These species were in an altitudinal range between 290 m and 831 m above sea level. Four species (C. angustifolia, C. alismatifolia, C. gracillima and C. rhabdota) were distributed in open gaps in dry dipterocarp forest. One species, C. parviflora was found in the contact zone between dry dipterocarp and bamboo (Gigantochloa sp.) forest. C. rhabdota was found only in a habitat with high humidity and shading along the Thailand-Lao PDR border. Significant ecological conditions of the natural habitats of these Curcuma species were identified. Altitude is the most important factor when determining the geographic distributions of these Curcuma species in Northeastern Thailand.

Changes in Carbon Pool and Stand Structure of a Native Subtropical Mangrove Forest after Inter-Planting with Exotic Species Sonneratia apetala

PubMed Central

Lu, Weizhi; Yang, Shengchang; Chen, Luzhen; Wang, Wenqing; Du, Xiaona; Wang, Canmou; Ma, Yan; Lin, Guangxuan; Lin, Guanghui

2014-01-01

In this study, we compared stand structure, biomass and soil carbon pools, and litterfall production between a mixed mangrove forest consisting of Aegiceras corniculatum inter-planted with the exotic Sonneratia apetala and a native monospecific forest dominated by A. corniculatum in the intertidal area of Zhanjiang, Guangdong Province, southeast China. The goal of this study was to test the hypothesis that inter-planting fast growing exotic mangrove S. apetala into subtropical native mangrove forests will significantly increase C sequestration. Although the tree heights and basal diameters of S. apetala were significantly higher than those of A. corniculatum, the density of the 12-year-old S. apetala trees in the mixed forest was much smaller than that of A. corniculatum in the monospecific forest. In contrast to several previous studies on S. apetala forests planted directly on mangrove-free mudflats, the mixed mangrove forest showed no significant difference in either standing biomass or soil carbon pools from the native monospecific mangrove forest (p = 0.294 and 0.073, respectively) twelve years after inter-planting with S. apetala. Moreover, carbon cycling was likely speeded up after inter-planting S. apetala due to higher litterfall input and lower C/N ratio. Thus, inter-planting fast-growing S. apetala into native mangrove forest is not an effective way to increase carbon sequestration in this subtropical mangrove forest. Given that exotic plant species may exert negative impact on native mangrove species and related epifauna, this fast-growing mangrove species is not suitable for mangrove plantation projects aiming mainly at enhancing carbon sequestration. PMID:24618793

Impact of Long-Term Forest Enrichment Planting on the Biological Status of Soil in a Deforested Dipterocarp Forest in Perak, Malaysia

PubMed Central

Karam, D. S.; Arifin, A.; Radziah, O.; Shamshuddin, J.; Majid, N. M.; Hazandy, A. H.; Zahari, I.; Nor Halizah, A. H.; Rui, T. X.

2012-01-01

Deforestation leads to the deterioration of soil fertility which occurs rapidly under tropical climates. Forest rehabilitation is one of the approaches to restore soil fertility and increase the productivity of degraded areas. The objective of this study was to evaluate and compare soil biological properties under enrichment planting and secondary forests at Tapah Hill Forest Reserve, Perak after 42 years of planting. Both areas were excessively logged in the 1950s and left idle without any appropriate forest management until 1968 when rehabilitation program was initiated. Six subplots (20 m × 20 m) were established within each enrichment planting (F1) and secondary forest (F2) plots, after which soil was sampled at depths of 0–15 cm (topsoil) and 15–30 cm (subsoil). Results showed that total mean microbial enzymatic activity, as well as biomass C and N content, was significantly higher in F1 compared to F2. The results, despite sample variability, suggest that the rehabilitation program improves the soil biological activities where high rate of soil organic matter, organic C, N, suitable soil acidity range, and abundance of forest litter is believed to be the predisposing factor promoting higher population of microbial in F1 as compared to F2. In conclusion total microbial enzymatic activity, biomass C and biomass N evaluation were higher in enrichment planting plot compared to secondary forest. After 42 years of planting, rehabilitation or enrichment planting helps to restore the productivity of planted forest in terms of biological parameters. PMID:22606055

Chapter 16: Inland Habitat Associations of Marbled Murrelets in British Columbia

Treesearch

Alan E. Burger

1995-01-01

Most Marbled Murrelets (Brachyramphus marmoratus) in British Columbia nest in the Coastal Western Hemlock biogeoclimatic zone. In this zone, detection frequencies were highest in the moister ecosections and in low elevation forests. Nests and moderately high levels of activity were also found in some forest patches in the subalpine Mountain Hemlock...

Avian Communities of Streamside Zones in The Ouachita Mountains of Arkansas

Treesearch

Ronald E. Thill; Philip A. Tappe; M. Anthony Melchiors; T. Bently Wigley

2004-01-01

Linear strips of forest along intermittent and perennial streams, commonly called streamside zones (SZs), are frequently retained for watershed protection and wildlife habitat enhancement in southern pine forests when adjacent stands are harvested. However, little is known regarding wildlife communities associated with SZs, particularly in relation to varying SZ widths...

Diversity and Spatial Structure of Belowground Plant–Fungal Symbiosis in a Mixed Subtropical Forest of Ectomycorrhizal and Arbuscular Mycorrhizal Plants

PubMed Central

Toju, Hirokazu; Sato, Hirotoshi; Tanabe, Akifumi S.

2014-01-01

Plant–mycorrhizal fungal interactions are ubiquitous in forest ecosystems. While ectomycorrhizal plants and their fungi generally dominate temperate forests, arbuscular mycorrhizal symbiosis is common in the tropics. In subtropical regions, however, ectomycorrhizal and arbuscular mycorrhizal plants co-occur at comparable abundances in single forests, presumably generating complex community structures of root-associated fungi. To reveal root-associated fungal community structure in a mixed forest of ectomycorrhizal and arbuscular mycorrhizal plants, we conducted a massively-parallel pyrosequencing analysis, targeting fungi in the roots of 36 plant species that co-occur in a subtropical forest. In total, 580 fungal operational taxonomic units were detected, of which 132 and 58 were probably ectomycorrhizal and arbuscular mycorrhizal, respectively. As expected, the composition of fungal symbionts differed between fagaceous (ectomycorrhizal) and non-fagaceous (possibly arbuscular mycorrhizal) plants. However, non-fagaceous plants were associated with not only arbuscular mycorrhizal fungi but also several clades of ectomycorrhizal (e.g., Russula) and root-endophytic ascomycete fungi. Many of the ectomycorrhizal and root-endophytic fungi were detected from both fagaceous and non-fagaceous plants in the community. Interestingly, ectomycorrhizal and arbuscular mycorrhizal fungi were concurrently detected from tiny root fragments of non-fagaceous plants. The plant–fungal associations in the forest were spatially structured, and non-fagaceous plant roots hosted ectomycorrhizal fungi more often in the proximity of ectomycorrhizal plant roots. Overall, this study suggests that belowground plant–fungal symbiosis in subtropical forests is complex in that it includes “non-typical” plant–fungal combinations (e.g., ectomycorrhizal fungi on possibly arbuscular mycorrhizal plants) that do not fall within the conventional classification of mycorrhizal symbioses, and in that associations with multiple functional (or phylogenetic) groups of fungi are ubiquitous among plants. Moreover, ectomycorrhizal fungal symbionts of fagaceous plants may “invade” the roots of neighboring non-fagaceous plants, potentially influencing the interactions between non-fagaceous plants and their arbuscular-mycorrhizal fungal symbionts at a fine spatial scale. PMID:24489745

Atlantic tropical forest mapping in the northern coastal zone of Sao Paulo State, Brazil

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

Simi, R. Jr.; Almeida, S.A.S.; Manso, A.P.

1997-06-01

The northern coastal zone of Sao Paulo State includes the cities of Ubatuba, Caraguatatuba, Sao Sebastiao and Ilha Bela. Large development projects, such as road and highway constructions and joint real estate exploration of susceptible coastal ecosystems have threatened the harmony and ecological stability of these ecosystems. Recently, the Atlantic tropical rain forest has been the most destructed ecosystem in the coastal zone in response to real estate investments in urban areas along the main roads. In the northern coastal zone of Sao Paulo State, 80% of the counties are included in the State Park of Serra do Mar. Asmore » tourism is a strong growing economical activity, as well as coastal production, it should be of interest to create a plan for sustainable development. The objective of this study is to map and characterize land use cover changes with emphasis on the Atlantic tropical rain forest degradation using Landsat TM images. Preliminary results for land use cover changes indicate that the Atlantic tropical rain forest was reduced by 6.1 % during the period of July 1992 and October 1995.« less

Succession Influences Wild Bees in a Temperate Forest Landscape: The Value of Early Successional Stages in Naturally Regenerated and Planted Forests

PubMed Central

Taki, Hisatomo; Okochi, Isamu; Okabe, Kimiko; Inoue, Takenari; Goto, Hideaki; Matsumura, Takeshi; Makino, Shun'ichi

2013-01-01

In many temperate terrestrial forest ecosystems, both natural human disturbances drive the reestablishment of forests. Succession in plant communities, in addition to reforestation following the creation of open sites through harvesting or natural disturbances, can affect forest faunal assemblages. Wild bees perform an important ecosystem function in human-altered and natural or seminatural ecosystems, as they are essential pollinators for both crops and wild flowering plants. To maintain high abundance and species richness for pollination services, it is important to conserve and create seminatural and natural land cover with optimal successional stages for wild bees. We examined the effects of forest succession on wild bees. In particular, we evaluated the importance of early successional stages for bees, which has been suspected but not previously demonstrated. A range of successional stages, between 1 and 178 years old, were examined in naturally regenerated and planted forests. In total 4465 wild bee individuals, representing 113 species, were captured. Results for total bees, solitary bees, and cleptoparasitic bees in both naturally regenerated and planted conifer forests indicated a higher abundance and species richness in the early successional stages. However, higher abundance and species richness of social bees in naturally regenerated forest were observed as the successional stages progressed, whereas the abundance of social bees in conifer planted forest showed a concave-shaped relationship when plotted. The results suggest that early successional stages of both naturally regenerated and conifer planted forest maintain a high abundance and species richness of solitary bees and their cleptoparasitic bees, although social bees respond differently in the early successional stages. This may imply that, in some cases, active forest stand management policies, such as the clear-cutting of planted forests for timber production, would create early successional habitats, leading to significant positive effects for bees in general. PMID:23457602

Succession influences wild bees in a temperate forest landscape: the value of early successional stages in naturally regenerated and planted forests.

PubMed

Taki, Hisatomo; Okochi, Isamu; Okabe, Kimiko; Inoue, Takenari; Goto, Hideaki; Matsumura, Takeshi; Makino, Shun'ichi

2013-01-01

In many temperate terrestrial forest ecosystems, both natural human disturbances drive the reestablishment of forests. Succession in plant communities, in addition to reforestation following the creation of open sites through harvesting or natural disturbances, can affect forest faunal assemblages. Wild bees perform an important ecosystem function in human-altered and natural or seminatural ecosystems, as they are essential pollinators for both crops and wild flowering plants. To maintain high abundance and species richness for pollination services, it is important to conserve and create seminatural and natural land cover with optimal successional stages for wild bees. We examined the effects of forest succession on wild bees. In particular, we evaluated the importance of early successional stages for bees, which has been suspected but not previously demonstrated. A range of successional stages, between 1 and 178 years old, were examined in naturally regenerated and planted forests. In total 4465 wild bee individuals, representing 113 species, were captured. Results for total bees, solitary bees, and cleptoparasitic bees in both naturally regenerated and planted conifer forests indicated a higher abundance and species richness in the early successional stages. However, higher abundance and species richness of social bees in naturally regenerated forest were observed as the successional stages progressed, whereas the abundance of social bees in conifer planted forest showed a concave-shaped relationship when plotted. The results suggest that early successional stages of both naturally regenerated and conifer planted forest maintain a high abundance and species richness of solitary bees and their cleptoparasitic bees, although social bees respond differently in the early successional stages. This may imply that, in some cases, active forest stand management policies, such as the clear-cutting of planted forests for timber production, would create early successional habitats, leading to significant positive effects for bees in general.

Factors driving natural regeneration beneath a planted urban forest

Treesearch

Danica A. Doroski; Alexander J. Felson; Mark A. Bradford; Mark P. Ashton; Emily E. Oldfield; Richard A. Hallett; Sara E. Kuebbing

2018-01-01

Cities around the world are investing in urban forest plantings as a form of green infrastructure. The aim is that these plantations will develop into naturally-regenerating native forest stands. However, woody plant recruitment is often cited as the most limiting factor to creating self-sustaining urban forests. As such, there is interest in site treatments that...

What is forest restoration?

Treesearch

John A. Stanturf

2005-01-01

The need to repair habitat and restore forest structure and funciton is recognized throughout the temperate and boreal zones as a component of sustainable forest management (Krishnaswamy and Hanson 1999; Dobson et al. 1997). Forest restoration is a complex task, complicated by diverse ecological and social conditions, that challenges our understanding of forest...

Soil respiration and photosynthetic uptake of carbon dioxide by ground-cover plants in four ages of jack pine forest

USGS Publications Warehouse

Striegl, Robert G.; Wickland, K.P.

2001-01-01

Soil carbon dioxide (CO2) emission (soil respiration), net CO2 exchange after photosynthetic uptake by ground-cover plants, and soil CO2 concentration versus depth below land surface were measured at four ages of jack pine (Pinus banksiana Lamb.) forest in central Saskatchewan. Soil respiration was smallest at a clear-cut site, largest in an 8-year-old stand, and decreased with stand age in 20-year-old and mature (60-75 years old) stands during May-September 1994 (12.1, 34.6, 31.5, and 24.9 mol C??m-2, respectively). Simulations of soil respiration at each stand based on continuously recorded soil temperature were within one standard deviation of measured flux for 48 of 52 measurement periods, but were 10%-30% less than linear interpolations of measured flux for the season. This was probably due to decreased soil respiration at night modeled by the temperature-flux relationships, but not documented by daytime chamber measurements. CO2 uptake by ground-cover plants ranged from 0 at the clear-cut site to 29, 25, and 9% of total growing season soil respiration at the 8-year, 20-year, and mature stands. CO2 concentrations were as great as 7150 ppmv in the upper 1 m of unsaturated zone and were proportional to measured soil respiration.

Whitefly Bemisia tabaci (Homoptera: Aleyrodidae) infestation on cassava genotypes grown at different ecozones in Nigeria.

PubMed

Ariyo, O A; Dixon, A G O; Atiri, G I

2005-04-01

Large-scale screening of cassava, Manihot esculenta Crantz, genotypes for resistance to infestation by whitefly Bemisia tabaci Gennadius, the vector of cassava mosaic geminiviruses, is limited. A range of new cassava elite clones were therefore assessed for the whitefly infestation in the 1999/2000 and 2000/2001 cropping seasons in experimental fields of International Institute of Tropical Agriculture, Ibadan, Nigeria. On each scoring day, between 0600 and 0800 hours when the whiteflies were relatively immobile, adult whitefly populations on the five topmost expanded leaves of cassava cultivars were counted. All through the 6-mo scoring period, there was a highly significant difference in whitefly infestation among the new cassava elite clones. Vector population buildup was observed in Ibadan (forest-savanna transition zone) and Onne (humid forest), 2 mo after planting (MAP). Mean infestation across cassava genotypes was significantly highest (16.6 whiteflies per plant) in Ibadan and lowest in Zaria (0.2). Generally, whitefly infestation was very low in all locations at 5 and 6 MAP. During this period, cassava genotypes 96/1439 and 91/02324 significantly supported higher infestations than other genotypes. Plants of 96/1089A and TMS 30572 supported the lowest whitefly infestation across cassava genotypes in all locations. The preferential whitefly visitation, the differences between locations in relation to whitefly population, cassava mosaic disease, and the fresh root yield of cassava genotypes are discussed.

Survival and rebound of Antillean dry forests: role of forest fragments

Treesearch

I.A. Ramjohn; P.G. Murphy; T.M. Burton; A.E. Lugo

2012-01-01

Antillean dry forests have experienced high levels of human impact for almost five centuries. Economic changes in the second half of the 20th century have facilitated forest recovery in Puerto Rico. We quantified the extent of forest cover and the community composition of representative forest fragments in the subtropical dry forest life zone (sensu Holdridge, 1967) in...

Polychlorinated biphenyls and polybrominated diphenylethers in soils from planted forests and adjacent natural forests on a tropical island.

PubMed

Liu, Xin; Wang, Shuai; Jiang, Yishan; Sun, Yingtao; Li, Jun; Zhang, Gan

2017-08-01

Transformation from natural forests to planted forests in tropical regions is an expanding global phenomenon causing major modifications of land cover and soil properties, e.g. soil organic carbon (SOC). This study investigated accumulations of POPs in soils under eucalyptus and rubber forests as compared with adjacent natural forests on Hainan Island, China. Results showed that due to the greater forest filter effect and the higher SOC, the natural forest have accumulated larger amounts of POPs in the top 20 cm soil. Based on correlation and air-soil equilibrium analysis, we highlighted the importance of SOC in the distribution of POPs. It is assumed that the elevated mobility of POPs in the planted forests was caused by greater loss of SOC and extensive leaching in the soil profile. This suggests that a better understanding of global POPs fate should take into consideration the role of planted forests. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elevational Patterns in Archaeal Diversity on Mt. Fuji

PubMed Central

Singh, Dharmesh; Takahashi, Koichi; Adams, Jonathan M.

2012-01-01

Little is known of how archaeal diversity and community ecology behaves along elevational gradients. We chose to study Mount Fuji of Japan as a geologically and topographically uniform mountain system, with a wide range of elevational zones. PCR-amplified soil DNA for the archaeal 16 S rRNA gene was pyrosequenced and taxonomically classified against EzTaxon-e archaeal database. At a bootstrap cut-off of 80%, most of the archaeal sequences were classified into phylum Thaumarchaeota (96%) and Euryarchaeota (3.9%), with no sequences classified into other phyla. Archaeal OTU richness and diversity on Fuji showed a pronounced ‘peak’ in the mid-elevations, around 1500 masl, within the boreal forest zone, compared to the temperate forest zone below and the alpine fell-field and desert zones above. Diversity decreased towards higher elevations followed by a subtle increase at the summit, mainly due to an increase in the relative abundance of the group I.1b of Thaumarchaeota. Archaeal diversity showed a strong positive correlation with soil NH4 +, K and NO3 − . Archaeal diversity does not parallel plant diversity, although it does roughly parallel bacterial diversity. Ecological hypotheses to explain the mid diversity bulge on Fuji include intermediate disturbance effects, and the result of mid elevations combining a mosaic of upper and lower slope environments. Our findings show clearly that archaeal soil communities are highly responsive to soil environmental gradients, in terms of both their diversity and community composition. Distinct communities of archaea specific to each elevational zone suggest that many archaea may be quite finely niche-adapted within the range of soil environments. A further interesting finding is the presence of a mesophilic component of archaea at high altitudes on a mountain that is not volcanically active. This emphasizes the importance of microclimate – in this case solar heating of the black volcanic ash surface – for the ecology of soil archaea. PMID:22970233

Impacts of Alien Tree Invasion on Evapotranspiration in Tropical Montane Cloud Forest in Hawai'i

NASA Astrophysics Data System (ADS)

Giambelluca, T. W.; Asner, G. P.; Martin, R. E.; Nullet, M. M.; Huang, M.; Delay, J. K.; Mudd, R. G.; Takahashi, M.

2007-12-01

Hawaiian tropical montane cloud forests (TMCFs) are ecologically and hydrologically valuable zones. TMCFs in Hawai'i serve as refugia for the remaining intact native terrestrial plant and animal ecosystems, and are major sources of hydrologic input to surface water and groundwater systems. Invasion of alien tree species, with obvious effects on the ecological integrity of TMCFs, also threatens to impact the hydrological services these forests provide. Much speculation has been made about the hydrological effects of replacing native forest tree species with alien trees in Hawai'i, but until now no measurements have been made to test these assertions. We established two study sites, each equipped with eddy covariance and other micrometeorological instrumentation, one within native Metrosideros polymorpha forest and the other at a site heavily invaded by Psidium cattleianum, in the cloud forest zone of Hawai'i Volcanoes National Park. We are conducting measurements of stand-level evapotranspiration, transpiration (using sapflow techniques), energy balance, throughfall, stemflow, and soil moisture at each site. Preliminary analysis of these measurements shows that the fraction of available energy used for evapotranspiration (ET Fraction) at the native site is much higher for wet canopy conditions. The ET Fraction at the native site has an annual cycle corresponding to the annual cycle in leaf area. Deviations from the annual cycle are more closely related to variations in canopy wetness than to variations in soil moisture. Overall, ET as a function of available energy is 27% higher at the invaded site than the native site. The difference in ET between the two sites is especially pronounced during dry canopy periods, during which the ET Fraction is 53% higher at the invaded site than the native site. Sapflow measurements using heat balance collars show that leaf-area-specific transpiration is much greater in invasive P. cattleianum trees than in remnant native M. polymorpha trees at the invaded site. These results indicate that the P. cattleianum invasion is altering the hydrological cycle of the TMCF where it is found, with potential significant negative consequences for island water supply.

Plant-pollinator interactions in tropical monsoon forests in Southeast Asia.

PubMed

Kato, Makoto; Kosaka, Yasuyuki; Kawakita, Atsushi; Okuyama, Yudai; Kobayashi, Chisato; Phimminith, Thavy; Thongphan, Daovorn

2008-11-01

Forests with different flora and vegetation types harbor different assemblages of flower visitors, and plant-pollinator interactions vary among forests. In monsoon-dominated East and Southeast Asia, there is a characteristic gradient in climate along latitude, creating a broad spectrum of forest types with potentially diverse pollinator communities. To detect a geographical pattern of plant-pollinator interactions, we investigated flowering phenology and pollinator assemblages in the least-studied forest type, i.e., tropical monsoon forest, in the Vientiane plain in Laos. Throughout the 5-year study, we observed 171 plant species blooming and detected flower visitors on 145 species. Flowering occurred throughout the year, although the number of flowering plant species peaked at the end of dry season. The dominant canopy trees, including Dipterocarpaceae, bloomed annually, in contrast to the supra-annual general flowering that occurs in Southeast Asian tropical rain forests. Among the 134 native plant species, 68 were pollinated by hymenopterans and others by lepidopterans, beetles, flies, or diverse insects. Among the observed bees, Xylocopa, megachilids, and honeybees mainly contributed to the pollination of canopy trees, whereas long-tongued Amegilla bees pollinated diverse perennials with long corolla tubes. This is the first community-level study of plant-pollinator interactions in an Asian tropical monsoon forest ecosystem.

SO2 damage to forests recorded by ERTS-1. [Ontario, Canada

NASA Technical Reports Server (NTRS)

Murtha, P. A.

1974-01-01

Sulfur dioxide fumes have been affecting the forests around Wawa, Ontario, which have been under surveillance for a number of years and were recently covered by ultra-small-scale (1:160,000) air photography for damage-assessment purposes. Image interpretation supported by electronic color enhancement was used to delineate on ERTS imagery three damage zones (total-kill, heavy-kill and medium-damage zones). The zones delineated on ERTS imagery are similar to the results of aerial sketch-mapping and air photo interpretation. Band 5 provided the greatest detail for assessing the damage to the forests, followed in successive order by bands 4, 6 and 7. Comparison with ERTS images obtained in the winter showed that even though the total-kill could be separated from heavy-kill damage zones, total-kill could not be consistently separated from clear-cut logging, burned areas, frozen lakes and bogs.

AmeriFlux US-CZ4 Sierra Critical Zone, Sierra Transect, Subalpine Forest, Shorthair

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

Goulden, Michael

This is the AmeriFlux version of the carbon flux data for the site US-CZ4 Sierra Critical Zone, Sierra Transect, Subalpine Forest, Shorthair. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is a lodgepole pine subalpine woodland with no recent disturbance.

Landscape variation of seasonal pool plant communities in forests of northern Minnesota, USA

Treesearch

Brian Palik; Dwight Streblow; Leanne Egeland; Richard Buech

2007-01-01

Seasonal forest pools are abundant in the northern Great Lakes forest landscape, but the range of variation in their plant communities and the relationship of this variation to multi-scale landscape features remains poorly quantified. We examined seasonal pools in forests of northern Minnesota USA with the objective of quantifying the range of variation in plant...

Microbial drivers of spatial heterogeneity of nitrous oxide pulse dynamics following drought in an experimental tropical rainforest

NASA Astrophysics Data System (ADS)

Young, J. C.; Sengupta, A.; U'Ren, J.; Van Haren, J. L. M.; Meredith, L. K.

2017-12-01

Nitrous oxide (N2O) is a long-lived, potent greenhouse gas with increasing atmospheric concentrations. Soil microbes in agricultural and natural ecosystems are the dominant source of N2O, which involves complex interactions between N-cycling microbes, metabolisms, soil properties, and plants. Tropical rainforests are the largest natural source of N2O, however the microbial and environmental drivers are poorly understood as few studies have been performed in these environments. Thus, there is an urgent need for further research to fill in knowledge gaps regarding tropical N-cycling, and the response of soil microbial communities to changes in precipitation patterns, temperature, nitrogen deposition, and land use. To address this data gap, we performed a whole-forest drought in the tropical rainforest biome in Biosphere 2 (B2) and analyzed connections between soil microbes, forest heterogeneity, and N2O emissions. The B2 rainforest is the hottest tropical rainforest on Earth, and is an important model system for studying the response of tropical forests to warming with controlled experimentation. In this study, we measured microbial community abundance and diversity profiles (16S rRNA and ITS2 amplicon sequencing) along with their association with soil properties (e.g. pH, C, N) during the drought and rewetting at five locations (3 depths), including regions that have been previously characterized with high and low N2O drought pulse dynamics (van Haren et al., 2005). In this study, we present the spatial distribution of soil microbial communities within the rainforest at Biosphere 2 and their correlations with edaphic factors. In particular, we focus on microbial, soil, and plant factors that drive high and low N2O pulse zones. As in the past, we found that N2O emissions were highest in response to rewetting in a zone hypothesized to be rich in nutrients from a nearby sugar palm. We will characterize microbial indicator species and nitrogen cycling genes to better resolve N cycling across the forest. Understanding how N2O formation is mediated by soil microbes in response to drought in tropical rainforests is challenging given the great diversity of microbial communities and metabolisms involved, but is critical for understanding the source of global increases in atmospheric N2O.

Diversity and Spatial-Temporal Distribution of Soil Macrofauna Communities Along Elevation in the Changbai Mountain, China.

PubMed

Yin, Xiuqin; Qiu, Lili; Jiang, Yunfeng; Wang, Yeqiao

2017-06-01

The understanding of patterns of vertical variation and diversity of flora and fauna along elevational change has been well established over the past century. However, it is unclear whether there is an elevational distribution pattern for soil fauna. This study revealed the diversity and spatial-temporal distribution of soil macrofauna communities in different vegetation zones from forest to alpine tundra along elevation of the Changbai Mountain, China. The abundance, richness, and Shannon-Wiener diversity index of soil macrofauna communities were compared in four distinguished vegetation zones including the coniferous and broadleaved mixed forest zone, the coniferous forest zone, the subalpine dwarf birch (Betula ermanii) forest zone, and the alpine tundra zone. Soil macrofauna were extracted in May, July, and September of 2009. In each season, the abundance and richness of the soil macrofauna decreased with the ascending elevation. The Shannon-Wiener diversity indices of the soil macrofauna were higher in the vegetation zones of lower elevation than of higher elevation. Significant differences were observed in the abundance, richness, and Shannon-Wiener diversity index for the studied vegetation zones. Soil macrofauna congregated mainly to the litter layer in the low-elevation areas and in the 0-5 cm soil layer of the higher elevation areas. The results emphasized that the diversity of soil macrofauna communities decreased as the elevation increased and possess the distinct characteristics of zonation in the mountain ecosystem. The diversity and distribution of soil macrofauna communities were influenced by mean annual precipitation, altitude, annual radiation quantity, and mean annual temperature. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Life in Tropical Rain Forests.

ERIC Educational Resources Information Center

NatureScope, 1989

1989-01-01

Discusses the diversity of rain forest life, the adaptations of rain forest plants and animals, and ways these organisms interact. Includes activities on canopy critters with a copyable sheet, rain forest revue, design a plant, and jungle sleuths. (RT)

Field guide for forested plant associations of the Wenatchee National Forest.

Treesearch

T.R. Lillybridge; B.L. Kovalchik; C.K. Williams; B.G. Smith

1995-01-01

A classification of forest vegetation is presented for the Wenatchee National Forest (NF). It is based on potential vegetation, with the plant association as the basic unit. The sample includes about 570 intensive plots and 840 reconnaissance plots distributed across the Wenatchee National Forest and the southwest portion of the Okanogan National Forest from 1975...

Corrections for Cluster-Plot Slop

Treesearch

Harry T. Valentine; Mark J. Ducey; Jeffery H. Gove; Adrian Lanz; David L.R. Affleck

2006-01-01

Cluster-plot designs, including the design used by the Forest Inventory and Analysis program of the USDA Forest Service (FIA), are attended by a complicated boundary slopover problem. Slopover occurs where inclusion zones of objects of interest cross the boundary of the area of interest. The dispersed nature of inclusion zones that arise from the use of cluster plots...

Forest restoration in the Nordic countries

Treesearch

Palle Madsen; Ása Arad•ttir; Emile Gardiner; Pelle Gemmel; Kåre Lund Høie; Magnus Löf; John A. Stanturf; Peter Tigerstedt; Hardi Tullus; Sauli Valkonen; Veiko Uri

2000-01-01

The Nordic countries include Iceland, Norway, Sweden, Finland, and Denmark, which range from lat. 54° in southern Denmark to lat. 72° at North Cape, Norway. This region is dominated by the boreal coniferous vegetational zone.Denmark and southern Sweden are, however, located in the deciduous (nemoral) forest zone, whereas the interior part of Iceland and the high...

Determining soil erosion from roads in coastal plain of Alabama

Treesearch

McFero Grace; W.J. Elliot

2008-01-01

This paper reports soil losses and observed sediment deposition for 16 randomly selected forest road sections in the National Forests of Alabama. Visible sediment deposition zones were tracked along the stormwater flow path to the most remote location as a means of quantifying soil loss from road sections. Volumes of sediment in deposition zones were determined by...

Random location of fuel treatments in wildland community interfaces: a percolation approach

Treesearch

Michael Bevers; Philip N. Omi; John G. Hof

2004-01-01

We explore the use of spatially correlated random treatments to reduce fuels in landscape patterns that appear somewhat natural while forming fully connected fuelbreaks between wildland forests and developed protection zones. From treatment zone maps partitioned into grids of hexagonal forest cells representing potential treatment sites, we selected cells to be treated...

Provisional tree seed zones and transfer guidelines for Alaska.

Treesearch

John N. Alden

1991-01-01

Four hundred and eighty-six provisional tree seed zones were delineated within 24 physiographic and climatic regions of Alaska and western Yukon Territory Estimated forest and potential forest land within altitudinal limits of tree species in Alaska was 51,853,000 hectares (128,130,000 acres) Seed transfer guidelines and standard labeling of seed collections are...

Silviculture-ecology of forest-zone hardwoods in the Sierra Nevada

Treesearch

Philip M. McDonald; John C. Tappeiner

1996-01-01

Although the principal hardwood species in the forest zone of the Sierra Nevada (California black oak, tanoak, Pacific madrone, and canyon live oak) are key components of many ecosystems, they have received comparatively little study. Currently they are underutilized and unmanaged. This paper brings together what is known on the silviculture-ecology of these species...

78 FR 6289 - Wallowa-Whitman National Forest; Oregon; Notice of Intent To Prepare a Supplement to the 2010...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-30

... Impact Statement for Wallowa-Whitman National Forest Invasive Plants Treatment AGENCY: Forest Service... USDA Forest Service will prepare a Supplement to the Wallowa-Whitman National Forest Invasive Plants Treatment Final Environmental Impact Statement (EIS) to address deficiencies identified by Judge Simon...

Quantifying water requirements of riparian river red gum (Eucalyptus camaldulensis) in the Murray-Darling Basin, Australia: Implications for the management of environmental flows

USGS Publications Warehouse

Doody, Tanya M.; Colloff, Matthew J.; Davies, Micah; Koul, Vijay; Benyon, Richard G.; Nagler, Pamela L.

2015-01-01

Water resource development and drought have altered river flow regimes, increasing average flood return intervals across floodplains in the Murray-Darling Basin, Australia, causing health declines in riparian river red gum (Eucalyptus camaldulensis) forests and woodlands. Environmental flow allocations helped to alleviate water stress during the recent Millennium Drought (1997–2010), however, quantification of the flood frequency required to support healthy E. camaldulensis communities is still needed. We quantified water requirements of E. camaldulensis for two years across a flood gradient (trees inundated at frequencies of 1:2, 1:5 and 1:10 years) at Yanga National Park, New South Wales to help inform management decision-making and design of environmental flows. Sap flow, evaporative losses and soil moisture measurements were used to determine transpiration, evapotranspiration and plant-available soil water before and after flooding. A formula was developed using plant-available soil water post-flooding and average annual rainfall, to estimate maintenance time of soil water reserves in each flood frequency zone. Results indicated that soil water reserves could sustain 1:2 and 1:5 trees for 15 months and six years, respectively. Trees regulated their transpiration rates, allowing them to persist within their flood frequency zone, and showed reduction in active sapwood area and transpiration rates when flood frequencies exceeded 1:2 years. A leaf area index of 0.5 was identified as a potential threshold indicator of severe drought stress. Our results suggest environmental water managers may have greater flexibility to adaptively manage floodplains in order to sustain E. camaldulensis forests and woodlands than has been appreciated hitherto.

Dynamics of forest health status in Slovakia from 1987 to 1994

Treesearch

Julius Oszlanyi

1998-01-01

Slovakia is a mountainous and forested country (40.6 percent forest cover) in central Europe and has a large variety of vegetation zones, forest types, and a rich diversity of forest tree species. The most important tree species are beech (Fagus sylvatica L.), Norway spruce (Picea abies Karst.), oak species (Quercus...

Bottomland hardwood reforestation for neotropical migratory birds: are we missing the forest for the trees?

USGS Publications Warehouse

Twedt, D.J.; Portwood, J.

1997-01-01

Reforestation of bottomland hardwoods on lands managed for wildlife or timber production has historically emphasized planting heavy-seeded oaks (Quercus spp.). Although techniques have been developed for successful oak establishment, these plantings often require 5 or more years before establishing a 3-dimensional forest structure. We suggest that lands planted to fast-growing early-successional species, in combination with oaks, provide: (1) more expedient benefits to Neotropical migratory birds; (2) greater forest diversity; (3) more rapid economic return to landowners; and (4) enhanced public relations. Under good growing conditions, and with effective weed control, some fast-growing species can develop a substantial 3-dimensional forest structure in as few as 2 or 3 years. Forest-breeding Neotropical migratory birds use stands planted with early successional species several years before sites planted solely with oaks. Where desirable, succession to forests with a high proportion of oak species can be achieved on sites initially planted with fast-growing species through silvicultural management.

Edge effects on growth and biomass partitioning of an Amazonian understory herb (Heliconia acuminata; Heliconiaceae).

PubMed

Bruna, Emilio M; de Andrade, Ana Segalin

2011-10-01

After deforestation, environmental changes in the remaining forest fragments are often most intense near the forest edge, but few studies have evaluated plant growth or plasticity of plant growth in response to edge effects. In a 2-year common garden experiment, we compared biomass allocation and growth of Heliconia acuminata with identical genotypes grown in 50 × 35 m common gardens on a 25-year-old edge and in a forest interior site. Genetically identical plants transplanted to the forest edge and understory exhibited different patterns of growth and biomass allocation. However, individuals with identical genotypes in the same garden often had very different responses. Plants on forest edges also had higher growth rates and increased biomass at the end of the experiment, almost certainly due to the increased light on the forest edge. With over 70000 km of forest edge created annually in the Brazilian Amazon, phenotypic plasticity may play an important role in mediating plant responses to these novel environmental conditions.

Influence of forest stands on soil and ecosystem carbon stocks in the conditions of the European part of Russia

NASA Astrophysics Data System (ADS)

Kaganov, Vladimir

2016-04-01

Forest stands are one of the most important components of ecosystems, both in Russia and around the world and at the same time forest vegetation is able to provide environment-modifying effect on the occupied landscape and, in particular, on the soil cover. Currently, due to the large interest in the carbon cycle, there is a question about the influence of forest vegetation on carbon stocks in ecosystems and in particular in the soil cover. To perform the study we selected 9 objects located in the European part of Russia from the area of the southern taiga to the semi-desert zone: Novgorod region, Kostroma region, Moscow region (2 objects), Penza region, Voronezh region, Volgograd region (2 objects) and Astrakhan region. For studying the influence of forest vegetation on the soil`s carbon, we organized the following experiment scheme: in each of the objects two key sites were selected, so that they originally were in the same soil conditions and the difference between them was only in a course development of vegetation - forest or grass. One part of the experimental sites, presenting forest vegetation, were the restored forests on abandoned lands with the age of 70-200 years. The second part of the experimental sites were artificial forest plantations aged from 60 to 112 years planted on the originally treeless forest-steppe or steppe landscapes. Perennial hayfields, perennial abandoned agricultural landscapes and virgin steppe areas were used as reference sites with grass vegetation. For each forest site we estimated the major carbon pools: phytomass, mortmass (dead wood, dry grass), debris, litter and soil. All data were recalculated using the conversion factors in carbon stocks in t C ha-1. We collected soil samples every 10 cm until the depth of 50 cm, and then at 50-75 and 75-100 cm soil layers. Bulk density and total organic carbon were determined by CHN analyzer. As a result, the soil`s carbon was also calculated into t C ha-1. We found out that the total carbon stocks were higher for the forestry vegetation than for the reference plots for all studied sites. Maximal values of carbon stocks (779±2 t C ha-1) were observed in forest sites of the forest-steppe zone (Voronezh region). These values decreased while moving both north and south and amounted for 236±1 t C ha-1 in south taiga (Novgorod region) and 104,5±7,4 t C ha-1 in semi-desert areas (Astrakhan region). The stock of total soil carbon significantly increased in 0-10 cm soil layer and decreased in 50-100 cm layer in the forest stands compared to the grass vegetation (T-test at significance level of 0.05). However, when considering the entire 100-cm layer of soil, there is no statistically significant difference in total carbon stock between forest and grass vegetation.

Converging Climate Sensitivities of European Forests Between Observed Radial Tree Growth and Vegetation Models

NASA Technical Reports Server (NTRS)

Zhang, Zhen; Babst, Flurin; Bellassen, Valentin; Frank, David; Launois, Thomas; Tan, Kun; Ciais, Philippe; Poulter, Benjamin

2017-01-01

The impacts of climate variability and trends on European forests are unevenly distributed across different bioclimatic zones and species. Extreme climate events are also becoming more frequent and it is unknown how they will affect feed backs of CO2 between forest ecosystems and the atmosphere. An improved understanding of species differences at the regional scale of the response of forest productivity to climate variation and extremes is thus important for forecasting forest dynamics. In this study, we evaluate the climate sensitivity of above ground net primary production (NPP) simulated by two dynamic global vegetation models (DGVM; ORCHIDEE and LPJ-wsl) against tree ring width (TRW) observations from about1000 sites distributed across Europe. In both the model simulations and the TRW observations, forests in northern Europe and the Alps respond positively to warmer spring and summer temperature, and their overall temperature sensitivity is larger than that of the soil-moisture-limited forests in central Europe and Mediterranean regions. Compared with TRW observations, simulated NPP from ORCHIDEE and LPJ-wsl appear to be overly sensitive to climatic factors. Our results indicate that the models lack biological processes that control time lags, such as carbohydrate storage and remobilization, that delay the effects of radial growth dynamics to climate. Our study highlights the need for re-evaluating the physiological controls on the climate sensitivity of NPP simulated by DGVMs. In particular, DGVMs could be further enhanced by a more detailed representation of carbon reserves and allocation that control year-to year variation in plant growth.

Postfire Forest Recovery in California's National Forests

NASA Astrophysics Data System (ADS)

Welch, K.; Young, T.; Safford, H.

2012-12-01

Due to fire suppression policies and other management practices over the last century, many low- to mid-elevation forest types in the Sierra Nevada have accumulated high fuel loads that promote stand-replacing high-intensity fires. Current and future projected trends in climate are predicted to increase the occurrence of such fires. We established over 1,000 plots in a range of elevations, environments, forest types, climate zones and fire severity classes to provide insight into the factors that promote natural tree regeneration after wildfires, the limiting factors in species establishment, and the differences in post-fire responses of conifers and hardwoods. We employed a standardized protocol that measured site characteristics, seedling densities, and woody plant growth. Preliminary results reveal that fire severity generally has a unimodal relationship with rates of natural regeneration, although effects of site and local environment act to modulate the shape of the relationship. Above low to moderate severities, natural regeneration rates of all tree species decrease with increasing severity, possibly due to a combination of factors including seed mortality, increasing distance to the nearest living seed tree, and more severe microclimatic conditions. Though hardwoods (oaks) are able to both seed and resprout from top-killed root crowns in a postfire environment, conifers still have the numerical advantage over hardwoods through seeding alone. We did not find evidence that shrubs have a strong either facilitative or competitive effect on conifer seedling establishment or growth in the first five years of forest recovery. Understanding forest recovery and regeneration processes after high severity fires is critical to appropriately applying management strategies on National Forest lands.

Germination, survival, and early growth of three invasive plants in response to five forest management regimes common to US northeastern deciduous forests

Treesearch

Cynthia D. Huebner; Adam E. Regula; David W. McGill

2018-01-01

The association between invasive plants and disturbance is well-documented. Most forest management regimes include disturbance (i.e., harvesting and fire) to improve regeneration of native plants, such as oaks. There is a need for land managers of northeastern forests to foster regeneration of native species without promoting invasive species establishment. We...

[The effect of forest exploitation on structure, diversity, and floristic composition of palmito-dominated Atlantic forests at Misiones, Argentina].

PubMed

Chediack, Sandra E

2008-06-01

The effect of forest exploitation--timber and palmito (Euterpe edulis, Palmae) extraction--on structure, diversity, and floristic composition of forests known as palmitals of the Atlantic Forest of Argentina was analyzed. These palmitals are located in Misiones (54 degrees 13' W and 25 degrees 41' S). Three 1 ha permanent plots were established: two in the "intangible" zone of the Iguazu National Park (PNI), and another in an exploited forest site bordering the PNI. Three 0.2 ha non-permanent plots were also measured. One was located in the PNI reserve zone where illegal palmito extraction occurs. The other two were in logged forest. All trees and palmitos with DBH >10 cm were identified and DBH and height were measured. For each of the six sites, richness and diversity of tree species, floristic composition, number of endemic species, and density of harvestable tree species were estimated. The harvest of E. edulis increases density of other tree species, diminishing palmito density. Forest explotation (logging and palmito harvest) is accompanied by an increase in diversity and density of heliophilic species, which have greater timber value in the region. However, this explotation also diminishes the density of palmito, of endemic species which normally grow in low densities, and of species found on the IUCN Red List. Results suggest that forest structure may be managed for timber and palmito production. The "intangible" zone of the PNI has the greatest conservation value in the Atlantic Forest, since a greater number of endemisms and endangered species are found here.

Effects of white-tailed deer and invasive plants on the herb layer of suburban forests.

PubMed

Morrison, Janet A

2017-11-01

Lack of hunting and predators and proximity to human communities make suburban forests prone to high deer abundance and non-native plant invasions. I investigated these likely drivers of community structure in the herb layers of six suburban forests in one region of New Jersey, USA. In 223 plots I assessed the herb layer response to 2.5 years with or without deer fencing and the early stage of invasion from seed additions of Microstegium vimineum , an invasive, annual grass. Non-native plants and herbaceous native plants were affected very little by fencing or M. vimineum invasion. In contrast, across all forests the combination of deer access and M. vimineum addition had a strongly negative effect on woody native percent cover. Forests differed in overall fencing effects on woody natives; their cover was greater in fenced plots in just three forests, suggesting greater deer pressure in those forests during the experiment. The early invasion by M. vimineum was greatest in two of these same forests, but was not influenced by fencing. Multi-group structural equation modelling compared two groups of forests that differed in vegetation abundance and other characteristics. It paralleled the results above and also showed no negative influence of non-native cover on native cover, even in the forests where non-native cover was greater. It identified a positive effect of light level on herb layer plants in the forests with less vegetation, and also revealed a positive effect of soil water potential (SWP) on non-native plants in the forests with more vegetation, which had higher SWP. These suburban forests within a common region varied widely in native and non-native herb layer abundance, the early success of M. vimineum invasion and the herb layer's response to early invasion and protection from deer.

Landscape variability of vegetation change across the forest to tundra transition of central Canada

NASA Astrophysics Data System (ADS)

Bonney, Mitchell Thurston

Widespread vegetation productivity increases in tundra ecosystems and stagnation, or even productivity decreases, in boreal forest ecosystems have been detected from coarse-scale remote sensing observations over the last few decades. However, finer-scale Landsat studies have shown that these changes are heterogeneous and may be related to landscape and regional variability in climate, land cover, topography and moisture. In this study, a Landsat Normalized Difference Vegetation Index (NDVI) time-series (1984-2016) was examined for a study area spanning the entirety of the sub-Arctic boreal forest to Low Arctic tundra transition of central Canada (i.e., Yellowknife to the Arctic Ocean). NDVI trend analysis indicated that 27% of un-masked pixels in the study area exhibited a significant (p < 0.05) trend and virtually all (99.3%) of those pixels were greening. Greening pixels were most common in the northern tundra zone and the southern forest-tundra ecotone zone. NDVI trends were positive throughout the study area, but were smallest in the forest zone and largest in the northern tundra zone. These results were supported by ground validation, which found a strong relationship (R2 = 0.81) between bulk vegetation volume (BVV) and NDVI for non-tree functional groups in the North Slave region of Northwest Territories. Field observations indicate that alder (Alnus spp.) shrublands and open woodland sites with shrubby understories were most likely to exhibit greening in that area. Random Forest (RF) modelling of the relationship between NDVI trends and environmental variables found that the magnitude and direction of trends differed across the forest to tundra transition. Increased summer temperatures, shrubland and forest land cover, closer proximity to major drainage systems, longer distances from major lakes and lower elevations were generally more important and associated with larger positive NDVI trends. These findings indicate that the largest positive NDVI trends were primarily associated with the increased productivity of shrubby environments, especially at, and north of the forest-tundra ecotone in areas with more favorable growing conditions. Smaller and less significant NDVI trends in boreal forest environments south of the forest-tundra ecotone were likely associated with long-term recovery from fire disturbance rather than the variables analyzed here.

Spatial and Temporal Relationships of Old-Growth and Secondary Forests in Indiana, USA

Treesearch

Martin A. Spetich; George R. Parker; Eric J. Gustafson

1997-01-01

We examined the spatial pattern of forests in Indiana to: (1) determine the extent, connectivity and percent edge of all forests, (2) examine the change in connectivity among these forests if all riparian zones were replanted to forest or other native vegetation, (3) determine the location, spatial dispersion and percent edge of current old-growth forest remnants, (4)...

Biodiversity and ecosystem processes: lessons from nature to improve management of planted forests for REDD-plus

Treesearch

Ian D. Thompson; Kimiko Okabe; John A. Parrotta; David I. Forrester; Eckehard Brockerhoff; Hervé Jactel; Hisatomo Taki

2014-01-01

Planted forests are increasingly contributing wood products and other ecosystem services at a global scale. These forests will be even more important as carbon markets develop and REDD-plus forest programs (forests used specifically to reduce atmospheric emissions of CO2 through deforestation and forest degradation) become common. Restoring degraded and deforested...

Migration and bioavailability of (137)Cs in forest soil of southern Germany.

PubMed

Konopleva, I; Klemt, E; Konoplev, A; Zibold, G

2009-04-01

To give a quantitative description of the radiocaesium soil-plant transfer for fern (Dryopteris carthusiana) and blackberry (Rubus fruticosus), physical and chemical properties of soils in spruce and mixed forest stands were investigated. Of special interest was the selective sorption of radiocaesium, which was determined by measuring the Radiocaesium Interception Potential (RIP). Forest soil and plants were taken at 10 locations of the Altdorfer Wald (5 sites in spruce forest and 5 sites in mixed forest). It was found that the bioavailability of radiocaesium in spruce forest was on average seven times higher than in mixed forest. It was shown that important factors determining the bioavailability of radiocaesium in forest soil were its exchangeability and the radiocaesium interception potential (RIP) of the soil. Low potassium concentration in soil solution of forest soils favors radiocaesium soil-plant transfer. Ammonium in forest soils plays an even more important role than potassium as a mobilizer of radiocaesium. The availability factor - a function of RIP, exchangeability and cationic composition of soil solution - characterized reliably the soil-plant transfer in both spruce and mixed forest. For highly organic soils in coniferous forest, radiocaesium sorption at regular exchange sites should be taken into account when its bioavailability is considered.

Closely-related taxa influence woody species discrimination via DNA barcoding: evidence from global forest dynamics plots.

PubMed

Pei, Nancai; Erickson, David L; Chen, Bufeng; Ge, Xuejun; Mi, Xiangcheng; Swenson, Nathan G; Zhang, Jin-Long; Jones, Frank A; Huang, Chun-Lin; Ye, Wanhui; Hao, Zhanqing; Hsieh, Chang-Fu; Lum, Shawn; Bourg, Norman A; Parker, John D; Zimmerman, Jess K; McShea, William J; Lopez, Ida C; Sun, I-Fang; Davies, Stuart J; Ma, Keping; Kress, W John

2015-10-12

To determine how well DNA barcodes from the chloroplast region perform in forest dynamics plots (FDPs) from global CTFS-ForestGEO network, we analyzed DNA barcoding sequences of 1277 plant species from a wide phylogenetic range (3 FDPs in tropics, 5 in subtropics and 5 in temperate zone) and compared the rates of species discrimination (RSD). We quantified RSD by two DNA barcode combinations (rbcL + matK and rbcL + matK + trnH-psbA) using a monophyly-based method (GARLI). We defined two indexes of closely-related taxa (Gm/Gt and S/G ratios) and correlated these ratios with RSD. The combination of rbcL + matK averagely discriminated 88.65%, 83.84% and 72.51% at the local, regional and global scales, respectively. An additional locus trnH-psbA increased RSD by 2.87%, 1.49% and 3.58% correspondingly. RSD varied along a latitudinal gradient and were negatively correlated with ratios of closely-related taxa. Successes of species discrimination generally depend on scales in global FDPs. We suggested that the combination of rbcL + matK + trnH-psbA is currently applicable for DNA barcoding-based phylogenetic studies on forest communities.

Water quality in New Zealand's planted forests: A review

Treesearch

Brenda R. Baillie; Daniel G. Neary

2015-01-01

This paper reviewed the key physical, chemical and biological water quality attributes of surface waters in New Zealand’s planted forests. The purpose was to: a) assess the changes in water quality throughout the planted forestry cycle from afforestation through to harvesting; b) compare water quality from planted forests with other land uses in New Zealand; and c)...

Patterns and determinants of plant biodiversity in non-commercial forests of eastern China

PubMed Central

Wu, Chuping; Vellend, Mark; Yuan, Weigao; Jiang, Bo; Liu, Jiajia; Shen, Aihua; Liu, Jinliang; Zhu, Jinru

2017-01-01

Non-commercial forests represent important habitats for the maintenance of biodiversity and ecosystem function in China, yet no studies have explored the patterns and determinants of plant biodiversity in these human dominated landscapes. Here we test the influence of (1) forest type (pine, mixed, and broad-leaved), (2) disturbance history, and (3) environmental factors, on tree species richness and composition in 600 study plots in eastern China. In total, we found 143 species in 53 families of woody plants, with a number of species rare and endemic in the study region. Species richness in mixed forest and broad-leaved forest was higher than that in pine forest, and was higher in forests with less disturbance. Species composition was influenced by environment factors in different ways in different forest types, with important variables including elevation, soil depth and aspect. Surprisingly, we found little effect of forest age after disturbance on species composition. Most non-commercial forests in this region are dominated by species poor pine forests and mixed young forests. As such, our results highlight the importance of broad-leaved forests for regional plant biodiversity conservation. To increase the representation of broad-leaved non-commercial forests, specific management practices such as thinning of pine trees could be undertaken. PMID:29161324

Patterns and determinants of plant biodiversity in non-commercial forests of eastern China.

PubMed

Wu, Chuping; Vellend, Mark; Yuan, Weigao; Jiang, Bo; Liu, Jiajia; Shen, Aihua; Liu, Jinliang; Zhu, Jinru; Yu, Mingjian

2017-01-01

Non-commercial forests represent important habitats for the maintenance of biodiversity and ecosystem function in China, yet no studies have explored the patterns and determinants of plant biodiversity in these human dominated landscapes. Here we test the influence of (1) forest type (pine, mixed, and broad-leaved), (2) disturbance history, and (3) environmental factors, on tree species richness and composition in 600 study plots in eastern China. In total, we found 143 species in 53 families of woody plants, with a number of species rare and endemic in the study region. Species richness in mixed forest and broad-leaved forest was higher than that in pine forest, and was higher in forests with less disturbance. Species composition was influenced by environment factors in different ways in different forest types, with important variables including elevation, soil depth and aspect. Surprisingly, we found little effect of forest age after disturbance on species composition. Most non-commercial forests in this region are dominated by species poor pine forests and mixed young forests. As such, our results highlight the importance of broad-leaved forests for regional plant biodiversity conservation. To increase the representation of broad-leaved non-commercial forests, specific management practices such as thinning of pine trees could be undertaken.

Fire, climate change, and forest resilience in interior Alaska

Treesearch

Jill F. Johnstone; F. Stuart Chapin; Teresa N. Hollingsworth; Michelle C. Mack; Vladimir Romanovsky; Merritt Turetsky

2010-01-01

In the boreal forests of interior Alaska, feedbacks that link forest soils, fire characteristics, and plant traits have supported stable cycles of forest succession for the past 6000 years. This high resilience of forest stands to fire disturbance is supported by two interrelated feedback cycles: (i) interactions among disturbance regime and plant-soil-microbial...

Invasive plants, insects, and diseases in the forests of the Anthropocene

Treesearch

Alexander M. Evans

2014-01-01

Invasive species, non-native plants, insects, and diseases can devastate forests. They outcompete native species, replace them in the ecosystem, and even drive keystone forest species to functional extinction. Invasives have negative effects on forest hydrology, carbon storage, and nutrient cycling. The damage caused by invasive species exacerbates the other forest...

Fluctuations in the East Asian monsoon recorded by pollen assemblages in sediments from the Japan Sea off the southwestern coast of Hokkaido, Japan, from 4.3 Ma to the present

NASA Astrophysics Data System (ADS)

Igarashi, Yaeko; Irino, Tomohisa; Sawada, Ken; Song, Lu; Furota, Satoshi

2018-04-01

We reconstructed fluctuations in the East Asian monsoon and vegetation in the Japan Sea region since the middle Pliocene based on pollen data obtained from sediments collected by the Integrated Ocean Drilling Program off the southwestern coast of northern Japan. Taxodiaceae conifers Metasequoia and Cryptomeria and Sciadopityacere conifer Sciadopitys are excellent indicators of a humid climate during the monsoon. The pollen temperature index (Tp) can be used as a proxy for relative air temperature. Based on changes in vegetation and reconstructed climate over a period of 4.3 Ma, we classified the sediment sequence into six pollen zones. From 4.3 to 3.8 Ma (Zone 1), the climate fluctuated between cool/moist and warm/moist climatic conditions. Vegetation changed between warm temperate mixed forest and cool temperate conifer forest. The Neogene type tree Carya recovered under a warm/moist climate. The period from 3.8 to 2.5 Ma (Zone 2) was characterized by increased Metasequoia pollen concentration. Warm temperate mixed forest vegetation developed under a cool/moist climate. The period from 2.5 to 2.2 Ma (Zone 3) was characterized by an abrupt increase in Metasequoia and/or Cryptomeria pollen and a decrease in warm broadleaf tree pollen, indicating a cool/humid climate. The Zone 4 period (2.2-1.7 Ma) was characterized by a decrease in Metasequoia and/or Cryptomeria pollen and an increase in cool temperate conifer Picea and Tsuga pollen, indicating a cool/moist climate. The period from 1.7 to 0.3 Ma (Zone 5) was characterized by orbital-scale climate fluctuations. Cycles of abrupt increases and decreases in Cryptomeria and Picea pollen and in Tp values indicated changes between warm/humid and cold/dry climates. The alpine fern Selaginella selaginoides appeared as of 1.6 Ma. Vegetation alternated among warm mixed, cool mixed, and cool temperate conifer forests. Zone 6 (0.3 Ma to present) was characterized by a decrease in Cryptomeria pollen. The warm temperate broadleaf forest and cool temperate conifer forest developed alternately under warm/moist and cold/dry climate. Zone 2 corresponded to a weak Tsushima Current breaking through the Tsushima Strait, and the beginning of orbital-scale climatic changes at 1.7 Ma during Zone 5 corresponded to the strong inflow of the Tsushima Current into the Japan Sea during interglacial periods (Gallagher et al., 2015).

Spatiotemporal distribution and variation of GPP in the Greater Khingan Mountains from 1982 to 2015

NASA Astrophysics Data System (ADS)

Hu, L.; Fan, W.; Liu, S.; Ren, H.; Xu, X.

2017-12-01

GPP (Gross Primary Productivity) is an important index to reflect the productivity of plants because it refers to the organic accumulated by green plants on land through assimilating the carbon dioxide in the atmosphere by photosynthesis and a serial of physiological processes in plants. Therefore, GPP plays a significant role in studying the carbon sink of terrestrial ecosystem and plants' reaction to global climate change. Remote sensing provides an efficient way to estimate GPP at regional and global scales and its products can be used to monitor the spatiotemporal variation of terrestrial ecosystem.As the Greater Khingan Mountains is the only bright coniferous forest of cool temperate zone in China and accounts for about 30% of the forest in China. This region is sensitive to climate change, but its forest coverage presented a significant variation due to fire disasters, excessive deforestation and so on. Here, we aimed at studying the variation pattern of GPP in the Greater Khingan Mountains and further found impact factors for the change in order to improve the understanding of what have and will happen on plants and carbon cycle under climate change.Based on GPP product from the GLASS program, we first studied spatial distribution of plants in the Greater Khingan Mountains from 1982 to 2015. With a linear regression model, seasonal and inter-annual GPP variability were explored on pixel and regional scale. We analyzed some climatic factors (e.g. temperature and precipitation) and terrain in order to find the driven factors for the GPP variations. The Growing Season Length (GSL) was also regarded as a factor and was retrieved from GIMMS 3g NDVI datasets using dynamic threshold method. We found that GPP in study area linearly decreased with the increasing elevation. Both annual accumulated GPP (AAG) and maximum daily GPP (during mid-June to mid-July) gained obvious improvement over the past 34 years under climate warming and drying (Fig.1 and Fig.2). Further studies showed temperature had positive correlation with GPP while precipitation had negative effect; Moreover, multi-regression results reflected that temperature rather than precipitation was the dominant climatic factor for plants in study area. The extension of GSL also increased the AAG.

Denitrification constitutes an import N sink in subtropical N-saturated forests - a nitrate dual isotope study

NASA Astrophysics Data System (ADS)

Yu, Lonfei; Zhu, Jing; Mulder, Jan; Dörsch, Peter

2016-04-01

Forests in China receive variable but increasing amounts of nitrogen from the atmosphere causing N saturation and nitrate runoff. Surprisingly high N-retention has been reported from subtropical forests, suggesting active mechanisms of N removal. Here we report a multi-site study of 15N and 18O abundances in soil nitrate (NO3-) across seven forested catchments spanning from temperate to subtropical China. In each catchment, samples were taken on one date during one or two summer along the hydrological continuum comprising hillslope positions and riparian zones. We had found previously in an intensive multi-year study at one of the sites, that the spatial pattern of summertime 15N and 18O in soil nitrate was remarkably stable across climatically distinct years, suggesting persistent N removal by denitrification at the foot of hill slopes and in groundwater discharge zones (Yu et al., submitted). In the present study, we extended the scope to five subtropical Chinese catchments and compared them with two temperate forests. Our data confirm the general pattern of efficient nitrification on hillslopes and strong denitrification in riparian zones in the subtropical catchments but not in the temperate ones. This is likely because high summer rainfalls at the monsoonal sites connect N mineralization and oxidation in upland positions with NO3- reduction in ground water discharge zones via NO3- runoff, rendering subtropical forests an efficient sink for reactive N with implications for regional N budgets. The impact of N deposition level, hydrology and edaphic factors on the predictive power of nitrate isotope signatures for N removal processes will be discussed. Yu L, Zhu J, Mulder J, Dörsch P: Spatiotemporal patterns in dual nitrate isotopes reveal efficient N transformation and denitrification along a hydrological continuum in N-saturated, subtropical forest. Submitted

Functional trait strategies of trees in dry and wet tropical forests are similar but differ in their consequences for succession.

PubMed

Lohbeck, Madelon; Lebrija-Trejos, Edwin; Martínez-Ramos, Miguel; Meave, Jorge A; Poorter, Lourens; Bongers, Frans

2014-01-01

Global plant trait studies have revealed fundamental trade-offs in plant resource economics. We evaluated such trait trade-offs during secondary succession in two species-rich tropical ecosystems that contrast in precipitation: dry deciduous and wet evergreen forests of Mexico. Species turnover with succession in dry forest largely relates to increasing water availability and in wet forest to decreasing light availability. We hypothesized that while functional trait trade-offs are similar in the two forest systems, the successful plant strategies in these communities will be different, as contrasting filters affect species turnover. Research was carried out in 15 dry secondary forest sites (5-63 years after abandonment) and in 17 wet secondary forest sites (<1-25 years after abandonment). We used 11 functional traits measured on 132 species to make species-trait PCA biplots for dry and wet forest and compare trait trade-offs. We evaluated whether multivariate plant strategies changed during succession, by calculating a 'Community-Weighted Mean' plant strategy, based on species scores on the first two PCA-axes. Trait spectra reflected two main trade-off axes that were similar for dry and wet forest species: acquisitive versus conservative species, and drought avoiding species versus evergreen species with large animal-dispersed seeds. These trait associations were consistent when accounting for evolutionary history. Successional changes in the most successful plant strategies reflected different functional trait spectra depending on the forest type. In dry forest the community changed from having drought avoiding strategies early in succession to increased abundance of evergreen strategies with larger seeds late in succession. In wet forest the community changed from species having mainly acquisitive strategies to those with more conservative strategies during succession. These strategy changes were explained by increasing water availability during dry forest succession and increasing light scarcity during wet forest succession. Although similar trait spectra were observed among dry and wet secondary forest species, the consequences for succession were different resulting from contrasting environmental filters.

Lysimeter Study of Plant Water Uptake in a Model Forest Ecosystem on Heavy Metal Contaminated Soil

NASA Astrophysics Data System (ADS)

Menon, M.; Abbaspour, K.; Schulin, R.; Oswald, S.

2003-04-01

We have been investigating the impact of heavy metal stress on the water regime of young forest ecosystems grown in 32 open top lysimeters (3 m in diameter and 1 m deep). The factorial treatments of the lysimeters include variations of rainwater acidity (acidic, ambient rain), subsoil type (acidic, calcareous), and soil contamination (with and without copper, zinc and cadmium in the top 20 cm). Each lysimeter was planted in spring of 2000 with the same selection of trees and herbaceous plants. All lysimeters are equipped with tensiometers for monitoring of pressure head and time domain reflectometry for measuring of water content. Irrigation was applied equally to all lysimeters through sprinkler devices. Drainage water was collected by means of canisters installed at the bottom of the lysimeters, and thus evapotranspiration could be calculated through water balancing. We monitored the water regime for two years including an imposed drought period. Significantly more water was extracted from the calcareous than the acidic subsoil. The water potential measurements show that also the heavy metal polluted topsoil had a significant influence on the water regime. Metal stress was particularly evident under reduced irrigation. We suspect that the roots were damaged in the contaminated topsoil. In contrast to the subsoil type, heavy metal pollution did not produce a significant effect on evapotranspiration (ET) though, and neither did acidic rain. Pot experiments confirmed that in presence of clean subsoil plants compensated for metal stress in contaminated topsoil by shifting their root activity from contaminated to uncontaminated zones.

Effectiveness of streamside management zones on water quality: pretreatment measurements

Treesearch

J.L. Boggs; G. Sun; S.G. McNulty; W. Swartley; E. Treasure

2008-01-01

The objective of this paired watershed study is to quantify the effects of upland forest harvesting and Streamside Management Zones (SMZs) on stream water quantity and quality in North Carolina. Four watersheds ranging from 12 to 28 hectares (i.e., two on Hill Forest and two on Umstead Research Farm) with perennial stream channels were gauged for flow monitoring and...

Effects of harvesting on nitrogen and phosphorus availability in riparian management zone soils in Minnesota, USA

Treesearch

Douglas N. Kastendick; Eric K. Zenner; Brian J. Palik; Randall K. Kolka; Charles R. Blinn

2012-01-01

Riparian management zones (RMZs) protect streams from excess nutrients, yet few studies have looked at soil nutrients in forested RMZs or the impacts of partial harvesting on nutrient availability. We investigated the impacts of upland clearcutting in conjunction with uncut and partially harvested RMZs (40% basal area reduction) on soil nutrients in forests in...

Water quality, biodiversity, and codes of practice in relation to harvesting forest plantations in streamside management zones

Treesearch

Daniel G. Neary; Philip J. Smethurst; Brenda Baillie; Kevin C. Petrone

2011-01-01

Streamside management zones (SMZs) are special landscape units that include riparian areas and adjacent lands that mitigate the movement of sediment, nutrients and other chemicals from upland forest and agricultural management areas into streams. The size, shape, and management of SMZs are governed by various combinations of economic, ecological, and regulatory factors...

Can we manage tropical landscapes? – an answer from the Caribbean perspective.

Treesearch

Ariel E. Lugo

2002-01-01

Humans have used Caribbean island landscapes for millennia. The conversion of wild lands to built-up lands or to agricultural lands in these tropical countries follows predictable patterns. Conversion of moist forest life zones and fertile flatlands is faster than conversion of wet and rain forest life zones and low fertility steep lands. In Puerto Rico, these trends...

Watershed scale assessment of the impact of forested riparian zones on stream water quality

Treesearch

J. A. Webber; K. W. J. Williard; M. R. Whiles; M. L. Stone; J. J. Zaczek; D. K. Davie

2003-01-01

Federal and state land management agencies have been promoting forest and grass riparian zones to combat non-point source nutrient and sediment pollution of our nations' waters. The majority of research examining the effectiveness of riparian buffers at reducing nutrient and sediment inputs to streams has been conducted at the field scale. This study took a...

Local indigenous knowledge about some medicinal plants in and around Kakamega forest in western Kenya.

PubMed

Otieno, Nickson Erick; Analo, Caleb

2012-01-01

Kakamega forest is Kenya's only rainforest and is distinguishably rich in biodiversity but threatened by agricultural encroachment and other forms of human activity. It is also one of Kenya's Important Bird Areas and a significant source of natural products to neighboring rural communities, such as medicinal plants, food, wood and other fibers. By using structured questionnaires for direct interviews, local indigenous knowledge was tapped through involvement of a focal group of elderly key informants in three blocks of the forest. Forty key species of medicinal plants used by local people were identified and recorded. Fifty-five percent of these were shrubs, thirty-two percent trees, seven-and-a-half percent lower plants such as herbs or forbs while five percent were climbers. About seventy percent of the medicinal plants occurred inside the forest itself and thirty percent around the edge and the immediate surroundings outside the forest. Thirty-eight (95%) of the plants were indigenous to Kenya and two (5%) exotic. Such extensive indigenous knowledge of the medicinal uses of the plants, including their distribution trends in the forest, may be tapped for decision support in rural health service planning, policy formulation for conserving the forest, tracking and mitigation of climate change impacts.

Remote sensing and today's forestry issues

NASA Technical Reports Server (NTRS)

Sayn-Wittgenstein, L.

1977-01-01

The actual and the desirable roles of remote sensing in dealing with current forestry issues, such as national forest policy, supply and demand for forest products and competing demands for forest land are discussed. Topics covered include wood shortage, regional timber inventories, forests in tropical and temperate zones, Skylab photography, forest management and protection, available biomass studies, and monitoring.

Effects of Model Choice and Forest Structure on Inventory-Based Estimations of Puerto Rican Forest Biomass.

Treesearch

THOMAS J. BRANDEIS; MARIA DEL ROCIO SUAREZ ROZO

2005-01-01

Total aboveground live tree biomass in Puerto Rican lower montane wet, subtropical wet, subtropical moist and subtropical dry forests was estimated using data from two forest inventories and published regression equations. Multiple potentially-applicable published biomass models existed for some forested life zones, and their estimates tended to diverge with increasing...

Effects of model choice and forest structure on inventory-based estimations of Puerto Rican forest biomass

Treesearch

Thomas J. Brandeis; Maria Del Rocio; Suarez Rozo

2005-01-01

Total aboveground live tree biomass in Puerto Rican lower montane wet, subtropical wet, subtropical moist and subtropical dry forests was estimated using data from two forest inventories and published regression equations. Multiple potentially-applicable published biomass models existed for some forested life zones, and their estimates tended to diverge with increasing...

Invasive plants found in east Texas forests, 2009 forest inventory and analysis factsheet

Treesearch

Sonja N. Oswalt; Christopher M. Oswalt

2011-01-01

This science update provides information on the presence and cover of nonnative invasive plants found in forests of the eastern region of the State of Texas based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station of the U.S. Department of Agriculture Forest Service in cooperation with the Texas Forest...

Role of eucalypt and other planted forests in biodiversity conservation and the provision of biodiversity-related services

Treesearch

Eckehard G. Brockerhoff; Hervé Jactel; John A. Parrotta; Silvio F.B. Ferraz

2013-01-01

Forests provide important habitat for much of the world’s biodiversity, and the continuing global deforestation is one of our greatest environmental concerns. Planted forests represent an increasing proportion of the global forest area and partly compensate for the loss of natural forest in terms of forest area, habitat for biodiversity and ecological function. At...

The mangement of national forests of eastern United States for non-timber forest products

Treesearch

James L. Chamberlain

2000-01-01

Many products are harvested fiom the forests of the United States in addition to timber. These non-timber forest products (NTFPs) are plants, parts of plants, or fungi that are harvested from within and on the edges of natural, disturbed or managed forests. Often, NTFPs are harvested from public forests for the socio-economic benefit they provide to rural collectors....

Invasive plants found in North Carolina’s forests, 2010—forest inventory and analysis factsheet

Treesearch

Christopher M. Oswalt; Sonja N. Oswalt

2014-01-01

This publication provides an overview of invasive plants found in forests of the State of North Carolina based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station (SRS) of the Forest Service, U.S. Department of Agriculture in cooperation with the North Carolina Forest Service. These estimates and coverage...

Biophysical climate impacts of recent changes in global forest cover.

PubMed

Alkama, Ramdane; Cescatti, Alessandro

2016-02-05

Changes in forest cover affect the local climate by modulating the land-atmosphere fluxes of energy and water. The magnitude of this biophysical effect is still debated in the scientific community and currently ignored in climate treaties. Here we present an observation-driven assessment of the climate impacts of recent forest losses and gains, based on Earth observations of global forest cover and land surface temperatures. Our results show that forest losses amplify the diurnal temperature variation and increase the mean and maximum air temperature, with the largest signal in arid zones, followed by temperate, tropical, and boreal zones. In the decade 2003-2012, variations of forest cover generated a mean biophysical warming on land corresponding to about 18% of the global biogeochemical signal due to CO2 emission from land-use change. Copyright © 2016, American Association for the Advancement of Science.

Forested plant associations of the Colville National Forest.

Treesearch

Clinton K. Williams; Brian F. Kelley; Bradley G. Smith; Terry R. Lillybridge

1995-01-01

A classification of forest vegetation is presented for the Colville National Forest in northeastern Washington State. It is based on potential vegetation with the plant association as the basic unit. The classification is based on a sample of approximately 229 intensive plots and 282 reconnaissance plots distributed across the forest from 1980 to 1983. The hierarchical...

Is Medieval Warm Period (MWP) wetter in Nagaland?

NASA Astrophysics Data System (ADS)

Misra, S.; Agarwal, D. S.; Bhattacharyya, D. A.

2017-12-01

Dzukou Valley, Nagaland is one of the biodiversity rich regions in northeast India. It is house to 113 families of plants where primitive angiosperms and endemic plants species contribute 19% and 6% respectively to this unique floristic wealth. Floristic uniqueness of the valley is that 50 families are represented by single genus and 128 genuses are represented by single species. Present work is the first attempt to use soil organic matter (SOM) d13C and pollen data to understand climate vis-à-vis vegetation dynamics in an area where climatic changes were not strong enough to induce a significant change in vegetation cover. The d13C values in our study range from -29.1‰ to -27.7‰ during late Holocene. These values are typical of forest soils and suggest organic carbon derived exclusively from C3 vegetation. Generated proxy data reveals three phases of climatic and vegetational shifts in the region since 3100 yr BP. During the first phase from 3100 yr BP to 2300 yr BP isotope data shows higher values, indicating towards a comparatively dry climate and area was occupies by dry Pine-Oak forest. Subsequently in second phase from 2300 yr BP to 1060 yr BP increase in arboreal pollens (tree elements) and gradually decreasing trend in d13C values from 2300 to 1060 yrs BP by 1.4 ‰ indicate towards comparatively moist climatic conditions corresponding to Medieval Warm Period. Later on in the third phase from 1060 yr BP onwards climate again climate turned dry and continued till date as postulated from the increasing trend in d13C values and good recovery of Pinus-Oak forest pollens.This study holds its significance not only as the first attempt to address palaeoclimate and palaeo-vegetation study from Nagaland but also as the first attempt to use SOM d13C along with pollen data to understand the influence of fluctuating rainfall (in a high rainfall zone) in altering the floristic wealth of a region. This type of study is essentially needed to address several issues related biodiversity loss, extent of endemism in high rainfall zone areas dominated by single type (C3 or C4) of vegetation.

Late Holocene and modern pollen records from three sites in Shannon and Carter Counties, southeast Missouri Ozarks

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

Huber, J.K.

Palynological investigations of a small sinkhole bog (Buttonbush Bog) and two archaeological sites (Round Spring Shelter, Round Spring Site 23SH19 and Gooseneck Site 23CT54) located in Shannon and Carter counties, Missouri provide a 3,100 year record of vegetational change. Bryophytic polsters and surface samples were also collected in Shannon and Carter counties in the southeast Missouri Ozarks to determine modern pollen rain. A 302-cm core retrieved from Buttonbush Bog has a basal data of 3,130 [+-] 100 yr B.P. and a date of 1,400 [+-] 100 yr B.P. at 52--56 cm. The Buttonbush Bog pollen sequence is divided into threemore » pollen-assemblage zones. The pollen spectra from Buttonbush Bog indicate that pine did not become well established in the southeast Missouri Ozarks until after 3,100 yr B.P. Zone 1 (the oldest) represents a mixed oak forest with minor components of pine and hickory. In Zone 2, pine values increase, indicating a shift to a pine-oak forest. The pollen sequence from Round Spring Shelter is divided into two pollen-assemblage zones. The lower zone (Zone 1) suggests the presence of a pine-oak forest in the vicinity of Round Spring prior to an Ambrosia rise at the top of the sequence in Zone 2. Regional pollen rain and variation in the local pollen rain are reflected by modern pollen spectra extracted from the bryophytic polsters surface samples. In this area the average regional pollen rain is dominated by pine, oak, hickory, and Ambrosia. The data are consistent with the mosaic of pine-oak and oak-hickory-pine forests characteristic of this region.« less

Long-term modeling of the forest-grassland ecotone in the French Alps: implications for land management and conservation.

PubMed

Carlson, Bradley Z; Renaud, Julien; Biron, Pierre Eymard; Choler, Philippe

2014-07-01

Understanding decadal-scale land-cover changes has the potential to inform current conservation policies. European mountain landscapes that include numerous protected areas provide a unique opportunity to weigh the long-term influences of land-use practices and climate on forest-grassland ecotone dynamics. Aerial photographs from four dates (1948, 1978, 1993, and 2009) were used to quantify the extent of forest and grassland cover at 5-m resolution across a 150-km2 area in a protected area of the southwestern French Alps. The study area included a grazed zone and a nongrazed zone that was abandoned during the 1970s. We estimated time series of a forestation index (FI) and analyzed the effects of elevation and grazing on FI using a hierarchical linear mixed effect model. Forest extent (composed primarily of mountain pine, Pinus uncinata) expanded from 50.6 km2 in 1948 to 85.5 km2 in 2009, i.e., a 23% increase in relative cover at the expense of grassland communities. Over the sixty-year period, the treeline rose by 118 m, from 1564 to 1682 m. Rapid forest expansion within the nongrazed zone followed the cessation of logging activities and was likely accelerated by climate warming during the 1980s. Within the grazed zone, the maintained presence of sheep did not fully counteract mountain pine expansion and led to highly contrasting rates of land-cover change based on the location of shepherds' cabins and water sources. Projections of FI for 2030 showed remnant patches of intensively used grasslands interspersed in a densely forested matrix. Our analysis of mountain land-cover dynamics provided strong evidence for forest encroachment into grassland habitat despite consistent grazing pressure. This pattern may be attributed to the disappearance of traditional land-use practices such as shrub burning and removal. Our findings prompt land managers to reconsider their initial conservation priority (i.e., the protection of a renowned mountain pine forest) and to implement proactive management strategies in order to preserve landscape heterogeneity and biological diversity. Projecting historical trends in the forest-grassland ecotone to 2030 provides stakeholders with a policy relevant tool for near-term land management.

Woody Species Diversity in Forest Plantations in a Mountainous Region of Beijing, China: Effects of Sampling Scale and Species Selection

PubMed Central

Zhang, Yuxin; Zhang, Shuang; Ma, Keming; Fu, Bojie; Anand, Madhur

2014-01-01

The role of forest plantations in biodiversity conservation has gained more attention in recent years. However, most work on evaluating the diversity of forest plantations focuses only on one spatial scale; thus, we examined the effects of sampling scale on diversity in forest plantations. We designed a hierarchical sampling strategy to collect data on woody species diversity in planted pine (Pinus tabuliformis Carr.), planted larch (Larix principis-rupprechtii Mayr.), and natural secondary deciduous broadleaf forests in a mountainous region of Beijing, China. Additive diversity partition analysis showed that, compared to natural forests, the planted pine forests had a different woody species diversity partitioning pattern at multi-scales (except the Simpson diversity in the regeneration layer), while the larch plantations did not show multi-scale diversity partitioning patterns that were obviously different from those in the natural secondary broadleaf forest. Compare to the natural secondary broadleaf forests, the effects of planted pine forests on woody species diversity are dependent on the sampling scale and layers selected for analysis. Diversity in the planted larch forest, however, was not significantly different from that in the natural forest for all diversity components at all sampling levels. Our work demonstrated that the species selected for afforestation and the sampling scales selected for data analysis alter the conclusions on the levels of diversity supported by plantations. We suggest that a wide range of scales should be considered in the evaluation of the role of forest plantations on biodiversity conservation. PMID:25545860

Carbon Dioxide Effects Research and Assessment Program. The role of tropical forests on the world carbon cycle

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

Brown, S.; Lugo, A. E.; Liegel, B.

1980-08-01

Tropical forests constitute about half of the world's forest and are characterized by rapid rates of organic matter turnover and high storages of organic matter. Tropical forests are considered to be one of the most significant terrestrial elements in the equation that balances the carbon cycle of the world. As discussed in the paper by Tosi, tropical and subtropical latitudes are more complex in terms of climate and vegetation composition than temperate and boreal latitudes. The implications of the complexity of the tropics and the disregard of this complexity by many scientists is made evident in the paper by Brownmore » and Lugo which shows that biomass estimates for tropical ecosystems have been overestimated by at least 100%. The paper by Brown shows that that rates of succession in the tropics are extremely rapid in terms of the ability of moist and wet forests to accumulate organic matter. Yet, in arid tropical Life Zones succession is slow. This leads to the idea that the question of whether tropical forests are sinks or sources of carbon must be analyzed in relation to Life Zones and to intensities of human activity in these Zones. The paper by Lugo presents conceptual models to illustrate this point and the paper by Tosi shows how land uses in the tropics also correspond to Life Zone characteristics. The ultimate significance of land use to the question of the carbon balance in a large region is addressed in the paper by Detwiler and Hall.« less

Air-Pollution-Mediated Changes in Alpine Ecosystems and Ecotones.

PubMed

Rusek, Josef

1993-08-01

Soil biological parameters (e.g., Collembola), soil types, soil chemical parameters (pH, humus substances), and plant communities were studied in different ecosystems and ecotones in alpine, subalpine, and spruce forest zones in the Tatra National Park, Slovak Republic. The preliminary, selected data, based on a long-term research program, showed a high sensitivity of some alpine ecotones and ecosystems to long-distance transported acid deposits. The changes in different ecosystem parameters since 1977 were more extensive in alpine grasslands on limestone than on granite. The greatest soil pH decrease was in the plant communities Festucetum versicoloris (-1.5 pH), Geranio-Alchemilletum crinitae (-1.32 pH), and Saxifragetum perdurantis (-1.25 pH), which are restricted to places with snow accumulation and water runoff gullies. In these ecosystems the greatest changes occurred in the leaching of humus substances. Some formerly less abundant and rare soil animals restricted to acid bedrock became dominant in some ecosystems on limestone as well as on granite; other formerly dominant species disappeared from the entire study area (e.g., Folsomia alpina). The aerial extent of some ecosystems changed substantially since 1977, and their surrounding ecotones moved into the space formerly occupied by one of the adjacent ecosystems. These changes are detectable by remote-sensing methods. In Central European mountains, strongly affected by global and regional industrial air pollution (e.g., Krusne Hory, Krkonose, Beskydy), spruce forests started to die back from higher to lower mountain elevations. The effects of air pollution on alpine and subalpine vegetation were not studied there. Strong alterations in alpine ecosystems and ecotones were detected by the author during long-term studies in the High Tatra Mountains, and I suggest that subalpine and mountain forest belts will be affected here in the near future as they were in the more polluted Central European mountains. The ecosystems and ecotones in higher alpine zones are likely to be affected earlier than the ecosystems at lower altitudes. Detection of ecosystem alteration in the alpine zone may be used for prediction of acidification processes and global change in ecosystems at lower altitudes. The consequences of global climate change are predictable by monitoring changes in the extent of some ecosystems located in discrete mountain geomorphological units (e.g., karstic sinkholes, water runoff gullies, wind shadows, ridges exposed to wind, etc.) and ecotones among them because of their dependence on duration of snow cover, water supply, wind and frost exposure, and other abiotic and biotic factors. © 1993 by the Ecological Society of America.

Previous land use alters plant allocation and growth in forest herbs

Treesearch

Jennifer M. Fraterrigo; Monica G. Turner; Scott M. Pearson

2006-01-01

Former human practices can persistently influence forest ecosystems, particularly by altering the distribution and abundance of vegetation. Previous research has focused on the role of colonization success in governing plant community patterns in abandoned forests, but few studies have explored how changes in the performance of adult plants may contribute to...

Riparian and wetland plant community types of the Shoshone National Forest

Treesearch

Gillian Walford; George Jones; Walt Fertig; Sabine Mellman-Brown; Kent E. Houston

2001-01-01

This classification of riparian and wetland plant communities in the Shoshone National Forest was a cooperative project between the Wyoming Natural Diversity Database (WYNDD) of The Nature Conservancy and the Shoshone National Forest. This project identifies groups of plant species that commonly occur together in particular environmental settings. Each such group of...

Response of native versus exotic plant guilds to cattle and elk herbivory in forested rangeland

Treesearch

Burak K. Pekin; Michael J. Wisdom; Catherine G. Parks; Bryan A. Endress; Bridgett J. Naylor; Ralf Ohlemuller

2015-01-01

Questions: Are exotic plant species favoured by non-native ungulate herbivores and disadvantaged by native herbivores in forested rangelands? Do the impacts of ungulates on exotic vs native plants depend on forest management activities such as prescribed fire and stand thinning?Location: Northeastern Oregon, USA....

Assessing the impact of planted forests on the global forest economy

Treesearch

Joseph Buongiorno; Shushuai Zhu

2014-01-01

Background: Planted forests are increasingly important in world forestry, natural resources conservation, and climate change policies. There is great interest in their potential for carbon sequestration and conservation of natural forests while they remain an essential source of fuelwood and industrial roundwood. Methods:...

Molecular Insights into Plant-Microbial Processes and Carbon Storage in Mangrove Ecosystems

NASA Astrophysics Data System (ADS)

Romero, I. C.; Ziegler, S. E.; Fogel, M.; Jacobson, M.; Fuhrman, J. A.; Capone, D. G.

2009-12-01

Mangrove forests, in tropical and subtropical coastal zones, are among the most productive ecosystems, representing a significant global carbon sink. We report new molecular insights into the functional relationship among microorganisms, mangrove trees and sediment geochemistry. The interactions among these elements were studied in peat-based mangrove sediments (Twin Cays, Belize) subjected to a long-term fertilization experiment with N and P, providing an analog for eutrophication. The composition and δ13C of bacterial PLFA showed that bacteria and mangrove trees had similar nutrient limitation patterns (N in the fringe mangrove zone, P in the interior zone), and that fertilization with N or P can affect bacterial metabolic processes and bacterial carbon uptake (from diverse mangrove sources including leaf litter, live and dead roots). PCR amplified nifH genes showed a high diversity (26% nifH novel clones) and a remarkable spatial and temporal variability in N-fixing microbial populations in the rhizosphere, varying primarily with the abundance of dead roots, PO4-3 and H2S concentrations in natural and fertilized environments. Our results indicate that eutrophication of mangrove ecosystems has the potential to alter microbial organic matter remineralization and carbon release with important implications for the coastal carbon budget. In addition, we will present preliminary data from a new study exploring the modern calibration of carbon and hydrogen isotopes of plant leaf waxes as a proxy recorder of past environmental change in mangrove ecosystems.

Quantifying nutrient uptake as driver of rock weathering in forest ecosystems by magnesium stable isotopes

NASA Astrophysics Data System (ADS)

Uhlig, David; Schuessler, Jan A.; Bouchez, Julien; Dixon, Jean L.; von Blanckenburg, Friedhelm

2017-06-01

Plants and soil microbiota play an active role in rock weathering and potentially couple weathering at depth with erosion at the soil surface. The nature of this coupling is still unresolved because we lacked means to quantify the passage of chemical elements from rock through higher plants. In a temperate forested landscape characterised by relatively fast (˜ 220 t km-2 yr-1) denudation and a kinetically limited weathering regime of the Southern Sierra Critical Zone Observatory (SSCZO), California, we measured magnesium (Mg) stable isotopes that are sensitive indicators of Mg utilisation by biota. We find that Mg is highly bio-utilised: 50-100 % of the Mg released by chemical weathering is taken up by forest trees. To estimate the tree uptake of other bio-utilised elements (K, Ca, P and Si) we compared the dissolved fluxes of these elements and Mg in rivers with their solubilisation fluxes from rock (rock dissolution flux minus secondary mineral formation flux). We find a deficit in the dissolved fluxes throughout, which we attribute to the nutrient uptake by forest trees. Therefore both the Mg isotopes and the flux comparison suggest that a substantial part of the major element weathering flux is consumed by the tree biomass. The enrichment of 26Mg over 24Mg in tree trunks relative to leaves suggests that tree trunks account for a substantial fraction of the net uptake of Mg. This isotopic and elemental compartment separation is prevented from obliteration (which would occur by Mg redissolution) by two potential effects. Either the mineral nutrients accumulate today in regrowing forest biomass after clear cutting, or they are exported in litter and coarse woody debris (CWD) such that they remain in solid biomass. Over pre-forest-management weathering timescales, this removal flux might have been in operation in the form of natural erosion of CWD. Regardless of the removal mechanism, our approach provides entirely novel means towards the direct quantification of biogenic uptake following weathering. We find that Mg and other nutrients and the plant-beneficial element Si (bio-elements) are taken up by trees at up to 6 m depth, and surface recycling of all bio-elements but P is minimal. Thus, in the watersheds of the SSCZO, the coupling between erosion and weathering might be established by bio-elements that are taken up by trees, are not recycled and are missing in the dissolved river flux due to erosion as CWD and as leaf-derived bio-opal for Si. We suggest that the partitioning of a biogenic weathering flux into eroded plant debris might represent a significant global contribution to element export after weathering in eroding mountain catchments that are characterised by a continuous supply of fresh mineral nutrients.

An assessment of invasive plant species monitored by the Northern Research Station Forest Inventory and Analysis Program, 2005 through 2010

Treesearch

Cassandra M. Kurtz

2013-01-01

Invasive plant species are a worldwide concern due to the high ecological and economic costs associated with their presence. This document describes the plant characteristics and regional distribution of the 50 invasive plant species monitored from 2005 through 2010 on forested Phase 2 (P2) Forest Inventory and Analysis (FIA) plots in the 24 states of the Northern...

A Checklist of Common Plants of the Appalachian Trail in the Jefferson National Forest, Virginia

Treesearch

Arnold Krochmal; Connie Krochmal

1981-01-01

This Note lists the plants that a hiker is likely to notice on the Appalachian Trail in the Jefferson National Forest, Virginia. The list is one of the results of an inventory of plant life along the Trail as it passes through Southern National Forests. Only plants that were conspicuous because of their size, large population, or leaf or flower color are listed. Fungi...

A Checklist of Common Plants of the Appalachian Trial in the Nantahala National Forest, North Carolina

Treesearch

Arnold Krochmal; Connie Krochmal

1980-01-01

This Note lists the plants that a hiker is likely to notice on the Appalachian Trail in the Nantahala Forest, North Carolina. The list is one ofthe results of an inventory of plant life along the Trail as it passes through Southern National Forests. Only plants that were conspicuous because of their size, large population, or leaf or flower color are listed. Fungi,...

Diversity and community structure of ectomycorrhizal fungi associated with Larix chinensis across the alpine treeline ecotone of Taibai Mountain.

PubMed

Han, Qisheng; Huang, Jian; Long, Dongfeng; Wang, Xiaobing; Liu, Jianjun

2017-07-01

Alpine treeline ecotones represent ecosystems that are vulnerable to climate change. We investigated the ectomycorrhizal (ECM) community, which has potential to stabilize alpine ecosystems. ECM communities associated with Larix chinensis were studied in four zones along a natural ecotone from a mixed forest stand over pure forest stands, the timberline, and eventually, the treeline (3050-3450 m) in Tabai Mountain, China. Sixty operational taxonomic units (OTUs) of ECM fungi were identified by sequencing the rDNA internal transcribed spacer of ECM tips. The richness of ECM species increased with elevation. The soil C/N ratio was the most important factor explaining ECM species richness. The treeline zone harbored some unique ECM fungi whereas no unique genera were observed in the timberline and pure forest zone. Elevation and topography were equally important factors influencing ECM communities in the alpine region. We suggest that a higher diversity of the ECM fungal community associated with L. chinensis in the treeline zone could result from niche differentiation.

The status of Puerto Rico's forests, 2003

Treesearch

Thomas J. Brandeis; Eileen H. Helmer; Sonja N. Oswalt

2007-01-01

Puerto Rico’s forest cover continues to increase and is now 57 percent for mainland Puerto Rico, 85 percent for Vieques, and 88 percent for Culebra. Subtropical dry forest occupies 50 346 ha, 6832 ha, 2591 ha, and 6217 ha on the islands of Puerto Rico, Vieques, Culebra, and Mona, respectively. Subtropical moist forest, the most prevalent forested life zone on...

Climate change vulnerabilities within the forestry sector for the Midwestern United States

Treesearch

Stephen D. Handler; Chris W. Swanston; Patricia R. Butler; Leslie A. Brandt; Maria K. Janowiak; Matthew D. Powers; P. Danielle. Shannon

2014-01-01

Forests are a defining landscape feature for much of the Midwest, from boreal forests surrounding the northern Great Lakes to oak-hickory forests blanketing the Ozarks. Savannas and open woodlands within this region mark a major transition zone between forest and grassland biomes within the U.S. Forests help sustain human communities in the region, ecologically,...

The impact of forest roads on understory plant diversity in temperate hornbeam-beech forests of Northern Iran.

PubMed

Deljouei, Azade; Abdi, Ehsan; Marcantonio, Matteo; Majnounian, Baris; Amici, Valerio; Sohrabi, Hormoz

2017-08-01

Forest roads alter the biotic and abiotic components of ecosystems, modifying temperature, humidity, wind speed, and light availability that, in turn, cause changes in plant community composition and diversity. We aim at investigating and comparing the diversity of herbaceous species along main and secondary forest roads in a temperate-managed hornbeam-beech forest, north of Iran. Sixteen transects along main and secondary forest roads were established (eight transects along main roads and eight along secondary roads). To eliminate the effect of forest type, all transects were located in Carpinetum-Fagetum forests, the dominant forest type in the study area. The total length of each transect was 200 m (100 m toward up slope and 100 m toward down slope), and plots were established along it at different distances from road edge. The diversity of herbaceous plant species was calculated in each plot using Shannon-Wiener index, species richness, and Pielou's index. The results showed that diversity index decreased when distance from road edge increases. This decreasing trend continued up to 60 m from forest road margin, and after this threshold, the index slightly increased. Depending on the type of road (main or secondary) as well as cut or fill slopes, the area showing a statistical different plant composition and diversity measured through Shannon-Wiener, species richness, and Pielou's index is up to 10 m. The length depth of the road edge effect found in main and secondary forest roads was small, but it could have cumulative effects on forest microclimate and forest-associated biota at the island scale. Forest managers should account for the effect of road buildings on plant communities.

Marine Riparian Vegetation Communities of Puget Sound

DTIC Science & Technology

2007-02-01

species . In areas of frequent disturbance, early successional trees , such as red alder and maple, dominated coastal forests. Douglas fir is currently...sea level to the mountain tops), forest types are broken into zones, represented by the dominant canopy ( tree ) species , or cli- max community, with...Within each zone, there is also vertical stratification of vegetation types, including dominant canopy tree species , understory trees and shrubs, and

An economic assessment of implementing streamside management zones in central Appalachian hardwood forests

Treesearch

Yaoxiang Li; Chris B. LeDoux; Jingxin Wang

2006-01-01

The effects of variable width of streamside management zones (25, 50, 75, and 100 ft) (SMZs) and removal level of trees (10%, 30%, and 50% of basal area) on production and cost of implementing SMZs in central Appalachian hardwood forests were simulated by using a computer model. Harvesting operations were performed on an 80-year-old generated natural hardwood stand...

Flat Branch monitoring project: stream water temperature and sediment responses to forest cutting in the riparian zone

Treesearch

Barton D. Clinton; James M. Vose; Dick L. Fowler

2010-01-01

Stream water protection during timber-harvesting activities is of primary interest to forest managers. In this study, we examine the potential impacts of riparian zone tree cutting on water temperature and total suspended solids. We monitored stream water temperature and total suspended solids before and after timber harvesting along a second-order tributary of the...

A case study assessing opportunity costs and ecological benefits of streamside management zones and logging systems for eastern hardwood forests

Treesearch

Chris B. LeDoux; Ethel Wilkerson

2006-01-01

Forest landowners, managers, loggers, land-use planners, and other decision and policy-makers need to understand the opportunity costs and ecological benefits associated with different widths of streamside management zones (SMZs). In this paper, a simulation model was used to assess the opportunity costs of SMZ retention for four different logging systems, two mature...

Natural Forest Biomass Estimation Based on Plantation Information Using PALSAR Data

PubMed Central

Avtar, Ram; Suzuki, Rikie; Sawada, Haruo

2014-01-01

Forests play a vital role in terrestrial carbon cycling; therefore, monitoring forest biomass at local to global scales has become a challenging issue in the context of climate change. In this study, we investigated the backscattering properties of Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) data in cashew and rubber plantation areas of Cambodia. The PALSAR backscattering coefficient (σ0) had different responses in the two plantation types because of differences in biophysical parameters. The PALSAR σ0 showed a higher correlation with field-based measurements and lower saturation in cashew plants compared with rubber plants. Multiple linear regression (MLR) models based on field-based biomass of cashew (C-MLR) and rubber (R-MLR) plants with PALSAR σ0 were created. These MLR models were used to estimate natural forest biomass in Cambodia. The cashew plant-based MLR model (C-MLR) produced better results than the rubber plant-based MLR model (R-MLR). The C-MLR-estimated natural forest biomass was validated using forest inventory data for natural forests in Cambodia. The validation results showed a strong correlation (R2 = 0.64) between C-MLR-estimated natural forest biomass and field-based biomass, with RMSE  = 23.2 Mg/ha in deciduous forests. In high-biomass regions, such as dense evergreen forests, this model had a weaker correlation because of the high biomass and the multiple-story tree structure of evergreen forests, which caused saturation of the PALSAR signal. PMID:24465908

Soil properties and soil nitrogen dynamics of prairie-like forest openings and surrounding forests in Kentucky's Knobs Region

Treesearch

C.C. Rhoades; S.P. Miller; M.M. Shea

2004-01-01

Herbaceous communities located within forest openings increase plant species diversity of forests in the Knobs Region of Kentucky. Although these grass-dominated communities are protected and managed for rare plant species conservation, it is unclear how soil conditions may delineate the grassland-forest boundary. We compared soil chemical and physical properties and...

Invasive plants found in Tennessee forests, 2009 forest inventory and analysis factsheet

Treesearch

Sonja N. Oswalt; Christopher M. Oswalt

2011-01-01

This science update provides an overview of nonnative invasive plants found in forests of the State of Tennessee based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station of the U.S. Department of Agriculture Forest Service in cooperation with the Tennessee Department of Agriculture Division of Forestry....

Invasive plants found in Georgia’s forests, 2010 - forest inventory and analysis factsheet

Treesearch

Sonja N. Oswalt; Christopher M. Oswalt

2014-01-01

This science update provides an overview of invasive plants found in forests of the State of Georgia based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station (SRS) of the U.S. Department of Agriculture, Forest Service in cooperation with the Georgia Forestry Commission. These estimates and coverage maps...

Invasive plants found in Oklahoma’s forests, 2010 - forest inventory and analysis factsheet

Treesearch

Sonja N. Oswalt; Christopher M. Oswalt

2014-01-01

This science update provides an overview of nonnative invasive plants found in Oklahoma forests based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station (SRS) of the U.S. Department of Agriculture Forest Service in cooperation with the Oklahoma Forestry Services. These estimates and coverage maps will be...

Invasive plants found in Mississippi forests, 2009 forest inventory and analysis factsheet

Treesearch

Sonja N. Oswalt; Christopher M. Oswalt

2011-01-01

This science update provides information on nonnative invasive plants in Mississippi’s forest land based on an annual inventory conducted by the U.S. Department of Agriculture Forest Service, Forest Inventory and Analysis (FIA) program at the Southern Research Station in cooperation with the Mississippi Forestry Commission. These estimates and coverage maps will be...

Invasive plants found in Virginia forests, 2010 - forest inventory and analysis factsheet

Treesearch

Christopher M. Oswalt; Sonja N. Oswalt

2013-01-01

This publication provides an overview of invasive plants found in forests of the State of Virginia based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station (SRS) of the Forest Service, U.S. Department of Agriculture in cooperation with the Virginia Department of Forestry. These estimates and coverage...

Invasive plants found in South Carolina forests, 2010 forest inventory and analysis factsheet

Treesearch

Christopher M. Oswalt; Sonja N. Oswalt

2012-01-01

This publication provides an overview of nonnative invasive plants found in forests of the State of South Carolina based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station (SRS) of the U.S. Department of Agriculture Forest Service in cooperation with the South Carolina Forestry Commission. These...

Invasive plants found in Kentucky forests, 2009 forest inventory and analysis factsheet

Treesearch

Christopher M. Oswalt; Sonja N. Oswalt

2012-01-01

This publication provides an overview of nonnative invasive plants found in forests of the Commonwealth of Kentucky based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station of the U.S. Department of Agriculture Forest Service in cooperation with the Kentucky Division of Forestry. These estimates and...

Invasive plants found in Alabama forests, 2009 forest inventory and analysis factsheet

Treesearch

Christopher M. Oswalt; Sonja N. Oswalt

2012-01-01

This publication provides an overview of nonnative invasive plants found in forests of the State of Alabama based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station of the U.S. Department of Agriculture Forest Service in cooperation with the Alabama Forestry Commission. These estimates and coverage maps...

Planted forests and biodiversity

Treesearch

Jean-Michel Carnus; John Parrotta; Eckehard G. Brockerhoff; Michel Arbez; Hervé Jactel; Antoine Kremer; David Lamb; Kevin O’Hara; Bradley Walters

2006-01-01

Expansion of planted forests and intensification of their management has raised concerns among forest managers and the public over the implications of these trends for sustainable production and conservation of forest biological diversity. We review the current state of knowledge on the impacts of plantation forestry on genetic and species diversity at different...

A management guide for invasive plants in southern forests

Treesearch

James H. Miller; Steven T. Manning; Stephen F. Enloe

2013-01-01

Invasions of nonnative plants into forests of the Southern United States continue to spread and include new species, increasingly eroding forest productivity, hindering forest use and management activities, and degrading diversity and wildlife habitat. This book provides the latest information on how to organize and enact prevention programs, build strategies,...

Restoration Concepts for Temperate and Boreal Forests of North America and Western Europe

Treesearch

John A. Stanturf; P. Madsen

2002-01-01

Throughout the boreal and temperate zones, forest restoration efforts attempt to counteract negative effects of conversion to other land use (afforestation and remediation) and disturbance and stress on existing forests (rehabilitation). Appropriate silvicultural practices can be designed for any forest restoration objective. Most common objectives include timber,...

Application of geoinformatics for landscape assessment and conserving forest biodiversity in northeast India

Treesearch

Ashish Kumar; Bruce G. Marcot; Gautam Talukdar; P.S. Roy

2012-01-01

Herein, we summarize our work, within forest ecosystems of Garo Hills in northeast India, on mapping vegetation and land cover conditions, delineating wildlife habitat corridors among protected areas, evaluating forest conservation values of influence zones bordering protected areas, analyzing dispersion patterns of native forests, and determining potential effects of...

Remote sensing-based estimation of annual soil respiration at two contrasting forest sites

NASA Astrophysics Data System (ADS)

Huang, Ni; Gu, Lianhong; Black, T. Andrew; Wang, Li; Niu, Zheng

2015-11-01

Soil respiration (Rs), an important component of the global carbon cycle, can be estimated using remotely sensed data, but the accuracy of this technique has not been thoroughly investigated. In this study, we proposed a methodology for the remote estimation of annual Rs at two contrasting FLUXNET forest sites (a deciduous broadleaf forest and an evergreen needleleaf forest). A version of the Akaike's information criterion was used to select the best model from a range of models for annual Rs estimation based on the remotely sensed data products from the Moderate Resolution Imaging Spectroradiometer and root-zone soil moisture product derived from assimilation of the NASA Advanced Microwave Scanning Radiometer soil moisture products and a two-layer Palmer water balance model. We found that the Arrhenius-type function based on nighttime land surface temperature (LST-night) was the best model by comprehensively considering the model explanatory power and model complexity at the Missouri Ozark and BC-Campbell River 1949 Douglas-fir sites. In addition, a multicollinearity problem among LST-night, root-zone soil moisture, and plant photosynthesis factor was effectively avoided by selecting the LST-night-driven model. Cross validation showed that temporal variation in Rs was captured by the LST-night-driven model with a mean absolute error below 1 µmol CO2 m-2 s-1 at both forest sites. An obvious overestimation that occurred in 2005 and 2007 at the Missouri Ozark site reduced the evaluation accuracy of cross validation because of summer drought. However, no significant difference was found between the Arrhenius-type function driven by LST-night and the function considering LST-night and root-zone soil moisture. This finding indicated that the contribution of soil moisture to Rs was relatively small at our multiyear data set. To predict intersite Rs, maximum leaf area index (LAImax) was used as an upscaling factor to calibrate the site-specific reference respiration rates. Independent validation demonstrated that the model incorporating LST-night and LAImax efficiently predicted the spatial and temporal variabilities of Rs. Based on the Arrhenius-type function using LST-night as an input parameter, the rates of annual C release from Rs were 894-1027 g C m-2 yr-1 at the BC-Campbell River 1949 Douglas-fir site and 818-943 g C m-2 yr-1 at the Missouri Ozark site. The ratio between annual Rs estimates based on remotely sensed data and the total annual ecosystem respiration from eddy covariance measurements fell within the range reported in previous studies. Our results demonstrated that estimating annual Rs based on remote sensing data products was possible at deciduous and evergreen forest sites.

Effects of white-tailed deer and invasive plants on the herb layer of suburban forests

PubMed Central

2017-01-01

Abstract Lack of hunting and predators and proximity to human communities make suburban forests prone to high deer abundance and non-native plant invasions. I investigated these likely drivers of community structure in the herb layers of six suburban forests in one region of New Jersey, USA. In 223 plots I assessed the herb layer response to 2.5 years with or without deer fencing and the early stage of invasion from seed additions of Microstegium vimineum, an invasive, annual grass. Non-native plants and herbaceous native plants were affected very little by fencing or M. vimineum invasion. In contrast, across all forests the combination of deer access and M. vimineum addition had a strongly negative effect on woody native percent cover. Forests differed in overall fencing effects on woody natives; their cover was greater in fenced plots in just three forests, suggesting greater deer pressure in those forests during the experiment. The early invasion by M. vimineum was greatest in two of these same forests, but was not influenced by fencing. Multi-group structural equation modelling compared two groups of forests that differed in vegetation abundance and other characteristics. It paralleled the results above and also showed no negative influence of non-native cover on native cover, even in the forests where non-native cover was greater. It identified a positive effect of light level on herb layer plants in the forests with less vegetation, and also revealed a positive effect of soil water potential (SWP) on non-native plants in the forests with more vegetation, which had higher SWP. These suburban forests within a common region varied widely in native and non-native herb layer abundance, the early success of M. vimineum invasion and the herb layer’s response to early invasion and protection from deer. PMID:29218140

Effects of flood inundation and invasion by Phalaris arundinacea on nitrogen cycling in an Upper Mississippi River floodplain forest

USGS Publications Warehouse

Swanson, Whitney; DeJager, Nathan R.; Strauss, Eric A.; Thomsen, Meredith

2017-01-01

Although floodplains are thought to serve as important buffers against nitrogen (N) transport to aquatic systems, frequent flooding and high levels of nutrient availability also make these systems prone to invasion by exotic plant species. Invasive plants could modify the cycling and availability of nutrients within floodplains, with effects that could feedback to promote the persistence of the invasive species and impact N export to riverine and coastal areas. We examined the effect of flooding on soil properties and N cycling at a floodplain site in Pool 8 of the Upper Mississippi River with 2 plant communities: mature native forest (Acer saccharinum) and patches of an invasive grass (Phalaris arundinacea). Plots were established within each vegetation type along an elevation gradient and sampled throughout the summers of 2013 and 2014. Spatial trends in flooding resulted in higher soil organic matter, porosity, and total nitrogen and carbon in low elevations. Nutrient processes and NH4+ and NO3− availability, however, were best explained by vegetation type and time after flooding. Phalaris plots maintained higher rates of nitrification and higher concentrations of available NH4+ and NO3−. These results suggest that invasion by Phalarismay make nitrogen more readily available and could help to reinforce this species' persistence in floodplain wetlands. They also raise the possibility that Phalaris may decrease floodplain N storage capacity and influence downstream transport of N to coastal zones.

Pollination and seed dispersal are the most threatened processes of plant regeneration

NASA Astrophysics Data System (ADS)

Neuschulz, Eike Lena; Mueller, Thomas; Schleuning, Matthias; Böhning-Gaese, Katrin

2016-07-01

Plant regeneration is essential for maintaining forest biodiversity and ecosystem functioning, which are globally threatened by human disturbance. Here we present the first integrative meta-analysis on how forest disturbance affects multiple ecological processes of plant regeneration including pollination, seed dispersal, seed predation, recruitment and herbivory. We analysed 408 pairwise comparisons of these processes between near-natural and disturbed forests. Human impacts overall reduced plant regeneration. Importantly, only processes early in the regeneration cycle that often depend on plant-animal interactions, i.e. pollination and seed dispersal, were negatively affected. Later processes, i.e. seed predation, recruitment and herbivory, showed overall no significant response to human disturbance. Conserving pollination and seed dispersal, including the animals that provide these services to plants, should become a priority in forest conservation efforts globally.

Nonnative Plants in the Inventory of Western Oregon Forests

Treesearch

Andrew N. Gray

2005-01-01

Vegetation data from the 1997 inventory of non-Federal forests in western Oregon were examined to assess the abundance of invasive nonnative plants detected by the inventory. Inventoried plants were the more common, identifiable species; composites and graminoids were underrepresented. Nonnative species were found on 1,040,000 ha (35 percent) of the non-Federal forest...

The invasion of southern forests by nonnative plants: current and future occupation, with impacts, management strategies, and mitigation approaches

Treesearch

James H. Miller; Dawn Lemke; John Coulston

2013-01-01

Key FindingsInvasive plants continue to escape into and spread through southern forests to eventually form exclusive infestations, and replace native communities to the detriment of forest productivity, biodiversity, ecosystem services, and human use potential.Over a 300-year period, invasive plants have been increasingly...

Forest Planting Sites in North Mississippi and West Tennessee

Treesearch

Walter M. Broadfoot

1951-01-01

Forest plantations in north central Mississippi and western Tennessee can produce merchantable timber on much land which erosion has made useless for other crops Forest plantings usually can decrease, stop, or forestall erosion economically. This paper describes the most important sites in the area, predicts what may be expected if they are planted to trees, and...

[Genetic engineering of forest woody plants].

PubMed

Mashkina, O S; Butorina, A K

2003-03-01

The present state of genetic engineering (GE) of forest woody plants is considered with special reference to the materials of the International Conference "Wood, Breeding, Biotechnology and Industrial Expectations" held in France in June, 2001. Main tree species subjected to GE are listed, aims of constructing transgenic plants discussed, and methods described. Major achievements in the field are considered along with the problems associated with the employment of GE in the breeding of forest woody plants.

Impacts of forest farm practice on small to medium-sized mammals at Kemasul forest reserve, Pahang, Malaysia

NASA Astrophysics Data System (ADS)

Razali, Nor Bazilah; Abdul-Rahim, Ahmad Rizal; Md-Nor, Shukor; Mohd-Taib, Farah Shafawati

2018-04-01

Exploitation of forest for commercial agriculture has taken toll on wildlife species worldwide. A forest farm project with the aim of compensating the forest loss has been implemented in Kemasul Forest Reserve, of Pahang State, Malaysia through plantation of fast growing and adaptable plant species. The objective of this study is to determine the impact of this practice on diversity. The study was conducted in a long strip of forest fragment, where two study sites with different landscape matrix types were chosen; oil palm plantation (JR) and Acacia mangium plantations (CM). A total of 75 individuals from 13 species and six families were collected at both sites. The result shows forest with A. mangium plantations matrix types yield higher species diversity. There are 10 shared species that can be found at both study sites including Callosciurus notatus, Hystrix brachyura, Macaca nemestrina, and Tupaia glis. However, some species only existed at selected sites such as Leopoldamys sabanus which can only be found at JR. On the other hand, Callosciurus nigrovittatus, Viverra tangalunga and Paradoxurus hermaphroditus were only recorded at CM. Out of all individuals collected, four of them are protected species as reported by IUCN. Callosciurus nigrovittatus is listed as Near Threatened while the other three species (Maxomys rajah, Maxomys whiteheadi, and Macaca nemestrina) are Vulnerable. If conservation efforts in Kemasul Forest Reserved are neglected, these four species would be exposed to critical threats that might cause them facing extinction in the future. Mann Whitney U test shows no significant difference of distribution and species richness of small to medium-sized mammals in both study sites (U=51.5, p=0.59). This study therefore reveals that although the compensatory forest plantation initiatives yield positive effect on diversity of mammal's species, it does not necessarily provide ample food resources to the wildlife, instead it serves as important buffer zones for wildlife movement.

Region-wide monitoring of exotic pest plants in southeastern forests by Forest Service and State Partners

Treesearch

James H. Miller

2001-01-01

The USDA Forest Service Research in partnership with State forestry agencies has initiated monitoring of 32 exotic plant tasa invading forests in the 13 southeastern States. The monitoring is on all forestlands, all ownerships, and is a recent addition to the National Forest Resources Inventory, ongoing since the 1930's. This is the first multi-state survey of...

The Vulnerability of Forest Ecosystems of Armenia to the Global Climate Change

NASA Astrophysics Data System (ADS)

Khachatryan, S.

2009-05-01

Climate changes characterized as global warming can lead to irreversible effects on regional and global scales, such as drought, pest attacks, diseases, excessive forest fires, and climate driven extinction of numerous animal and plant species. We assess the issues that the development of forestry in Armenia faces, where the climate change is causing the landscape zone borders in the territory to shift. This will have a significant impact on the most vulnerable tree species in Armenia. An increase in climate aridity and intensification of desertification can be expected under the projected escalated temperatures and reduced precipitation. For example, we can consider average annual temperature of the Ijevan meteorological station (located in forestry region) for the period of 1936-2008. We analyze the vulnerability of forest ecosystems in Armenia to climatic and anthropogenic factors for the period of 1936-2008. Temperature and precipitation data from 25 meteorological stations in the territory of Armenia is studied for the period of 1936-2008. The dynamic of average temperature annual anomalies are revealed. The deviations of temperature and precipitation from the norms (average for 1961-1990) are evaluated for the period of study. We discuss the reasons for the abrupt increase in temperature and decrease in precipitation. Based on the dataset, the possible near future impact of global climate change on the Armenian forest ecosystems is discussed, and measures on the adaptation to the adverse consequences that climate change has on forests are offered.

Functional Trait Strategies of Trees in Dry and Wet Tropical Forests Are Similar but Differ in Their Consequences for Succession

PubMed Central

Lohbeck, Madelon; Lebrija-Trejos, Edwin; Martínez-Ramos, Miguel; Meave, Jorge A.; Poorter, Lourens; Bongers, Frans

2015-01-01

Global plant trait studies have revealed fundamental trade-offs in plant resource economics. We evaluated such trait trade-offs during secondary succession in two species-rich tropical ecosystems that contrast in precipitation: dry deciduous and wet evergreen forests of Mexico. Species turnover with succession in dry forest largely relates to increasing water availability and in wet forest to decreasing light availability. We hypothesized that while functional trait trade-offs are similar in the two forest systems, the successful plant strategies in these communities will be different, as contrasting filters affect species turnover. Research was carried out in 15 dry secondary forest sites (5-63 years after abandonment) and in 17 wet secondary forest sites (<1-25 years after abandonment). We used 11 functional traits measured on 132 species to make species-trait PCA biplots for dry and wet forest and compare trait trade-offs. We evaluated whether multivariate plant strategies changed during succession, by calculating a ‘Community-Weighted Mean’ plant strategy, based on species scores on the first two PCA-axes. Trait spectra reflected two main trade-off axes that were similar for dry and wet forest species: acquisitive versus conservative species, and drought avoiding species versus evergreen species with large animal-dispersed seeds. These trait associations were consistent when accounting for evolutionary history. Successional changes in the most successful plant strategies reflected different functional trait spectra depending on the forest type. In dry forest the community changed from having drought avoiding strategies early in succession to increased abundance of evergreen strategies with larger seeds late in succession. In wet forest the community changed from species having mainly acquisitive strategies to those with more conservative strategies during succession. These strategy changes were explained by increasing water availability during dry forest succession and increasing light scarcity during wet forest succession. Although similar trait spectra were observed among dry and wet secondary forest species, the consequences for succession were different resulting from contrasting environmental filters. PMID:25919023

Water availability determines the richness and density of fig trees within Brazilian semideciduous forest landscapes

NASA Astrophysics Data System (ADS)

Coelho, Luís Francisco Mello; Ribeiro, Milton Cezar; Pereira, Rodrigo Augusto Santinelo

2014-05-01

The success of fig trees in tropical ecosystems is evidenced by the great diversity (+750 species) and wide geographic distribution of the genus. We assessed the contribution of environmental variables on the species richness and density of fig trees in fragments of seasonal semideciduous forest (SSF) in Brazil. We assessed 20 forest fragments in three regions in Sao Paulo State, Brazil. Fig tree richness and density was estimated in rectangular plots, comprising 31.4 ha sampled. Both richness and fig tree density were linearly modeled as function of variables representing (1) fragment metrics, (2) forest structure, and (3) landscape metrics expressing water drainage in the fragments. Model selection was performed by comparing the AIC values (Akaike Information Criterion) and the relative weight of each model (wAIC). Both species richness and fig tree density were better explained by the water availability in the fragment (meter of streams/ha): wAICrichness = 0.45, wAICdensity = 0.96. The remaining variables related to anthropic perturbation and forest structure were of little weight in the models. The rainfall seasonality in SSF seems to select for both establishment strategies and morphological adaptations in the hemiepiphytic fig tree species. In the studied SSF, hemiepiphytes established at lower heights in their host trees than reported for fig trees in evergreen rainforests. Some hemiepiphytic fig species evolved superficial roots extending up to 100 m from their trunks, resulting in hectare-scale root zones that allow them to efficiently forage water and soil nutrients. The community of fig trees was robust to variation in forest structure and conservation level of SSF fragments, making this group of plants an important element for the functioning of seasonal tropical forests.

Soil and vegetation carbon turnover times across forest biomes in eastern China

NASA Astrophysics Data System (ADS)

Wang, Jingsong; Niu, Shuli

2017-04-01

1. Resent studies reveal that terrestrial biosphere is now a net carbon (C) sink for atmospheric C dixoide (CO2), however, whether this C sink can persist with climate change is still uncertain. Such uncertainty comes not only from C input, but also largely from C turnover times in an ecosystem. Knowledge of C turnover times is critical for modelling C cycle and evaluating C sink potential. Our current understanding of how long C can be stored in soils and vegetation and what are their controlling factors are still poorly understood. 2. We used C stocks from 1087 plots in soils and 2753 plots in vegetation and investigated the spatial patterns and controlling factors of C turnover times across the forest transect in the eastern China. 3. Our results showed a clear latitudinal pattern of C turnover times, with the lowest turnover times in the low-latitude zones and highest values in the high-latitude. Mean annual temperature (MAT) and mean annual precipitation (MAP) were the most important controlling factors on the soil C turnover times while forest age accounted for the most majority of variations in the vegetation C turnover times. Our findings also indicated that forest origin (planted forest, natural forest) was also responsible for the variations of vegetation C turnover times while forest type and soil properties were not the dominant controlling factors. 4. Our study highlights different dominant controlling factors on the soils and vegetation C turnover times and different mechanisms underlying above- and below-ground C turnover. The findings can help to better understand and reduce the large uncertainty in predictive models of the coupled carbon-climate system.

Mycorrhiza of plants in different vegetation types in tropical ecosystems of Xishuangbanna, southwest China.

PubMed

Muthukumar, T; Sha, Liqing; Yang, Xiaodong; Cao, Min; Tang, Jianwei; Zheng, Zheng

2003-12-01

We examined plants growing in four tropical vegetation types (primary forest, secondary forest, limestone forest and a slash and burn field) in Xishuangbanna, southwest China for mycorrhizal associations. Of the 103 plant species examined (belonging to 47 families), 81 had arbuscular mycorrhizal (AM) associations, while three species possessed orchid mycorrhiza. AM colonization levels ranged between 6% and 91% and spore numbers ranged between 1.36 spores and 25.71 spores per 10 g soil. Mean AM colonization level was higher in primary and secondary forest species than in plant species from limestone forests and a slash and burn field. In contrast, mean AM fungal spore numbers of the primary and limestone forest were lower than in the secondary forest or the slash and burn field. AM fungal spores belonging to Glomus and Acaulospora were the most frequent in soils of Xishuangbanna. AM fungal colonization and spore numbers were significantly correlated to each other and were significantly influenced by vegetation type.

Plant rhizosphere species-specific stoichiometry and regulation of extracellular enzyme and microbial community structure

NASA Astrophysics Data System (ADS)

Bell, C. W.; Calderon, F.; Pendall, E.; Wallenstein, M. D.

2012-12-01

Plant communities affect the activity and composition of soil microbial communities through alteration of the soil environment during root growth; substrate availability through root exudation; nutrient availability through plant uptake; and moisture regimes through transpiration. As a result, positive feedbacks in soil properties can result from alterations in microbial community composition and function in the rhizosphere zone. At the ecosystem-scale, many properties of soil microbial communities can vary between forest stands dominated by different species, including community composition and stoichiometry. However, the influence of smaller individual plants on grassland soils and microbial communities is less well documented. There is evidence to suggest that some plants can modify their soil environment in a manner that favors their persistence. For example, when Bromus tectorum plants invade, soil microbial communities tend to have higher N mineralization rates (in the rhizosphere zone) relative to native plants. If tight linkages between individual plant species and microbial communities inhabiting the rhizosphere exist, we hypothesized that any differences among plant species specific rhizosphere zones could be observed by shifts in: 1) soil -rhizosphere microbial community structure, 2) enzymatic C:N:P acquisition activities, 3) alterations in the soil C chemistry composition in the rhizosphere, and 4) plant - soil - microbial C:N:P elemental stoichiometry. We selected and grew 4 different C3 grasses species including three species native to the Shortgrass Steppe region (Pascopyrum smithii, Koeleria macrantha, and Vulpia octoflora) and one exotic invasive plant species (B. tectorum) in root-boxes that are designed to allow for easy access to the rhizosphere. The field soil was homogenized using a 4mm sieve and mixed 1:1 with sterile sand and seeded as monocultures (24 replicate root - boxes for each species). Plant and soil samples (along with no - plant control soil samples) were collected on day 28, 78, and 148 (N = 4 /sample period/species). Microbial community structure was quantified using the barcoded pyrosequencing protocols. We measured the potential activity of seven hydrolytic soil enzymes to represent the degradation of C, N, and P-rich substrates. Soil microbial C:N biomass responses to specific plant rhizospheres (MBC and MBN) were measured using the chloroform fumigation extraction method followed by DOC & N analysis. Fourier Transform Infrared Spectroscopy was used to assess differences in plant and soil C chemistry. We found that species specific rhizospheres are characteristic of very different soil chemical, edaphic, and microbial properties. These plant species act as gateways that introduce variability into soil C, N, and P ecosystem functional dynamics directly facilitated by rhizosphere - microbe associations. Our results suggest that nutrient stoichiometry within plant species' rhizospheres is a useful tool for identifying intra-ecosystem functional patterns. By identifying what and how specific species rhizospheres differ among the overall plant community, we can better predict how below-ground microbial community function and subsequent ecosystem processes can be influenced by alterations in plant community shifts based on the rhizosphere effects.

Evolution of soil, ecosystem, and critical zone research at the USDA FS Calhoun Experimental Forest

Treesearch

Daniel deB Richter; Allan R. Bacon; Sharon A. Billings; Dan Binkley; Marilyn Buford; Mac Callaham; Amy E. Curry; Ryan L. Fimmen; A. Stuart Grandy; Paul R. Heine; Michael Hofmockel; Jason A. Jackson; Elisabeth LeMaster; Jianwei Li; Daniel Markewitz; Megan L. Mobley; Mary W. Morrison; Michael S. Strickland; Thomas Waldrop; Carol G. Wells

2015-01-01

The US Department of Agriculture (USDA) Forest Service Calhoun Experimental Forest was organized in 1947 on the southern Piedmont to engage in research that today is called restoration ecology, to improve soils, forests, and watersheds in a region that had been severely degraded by nearly 150 years farming. Today, this 2,050-ha research forest is managed by the Sumter...

Contributions of water supply from the weathered bedrock zone to forest soil quality

Treesearch

James H. Witty; Robert C. Graham; Kenneth R. Hubbert; James A. Doolittle; Jonathan A. Wald

2003-01-01

One measure of forest soil quality is the ability of the soil to support tree growth. In mediterranean-type ecosystems, such as most of California's forests, there is virtually no rainfall during the summer growing season, so trees must rely on water stored within the substrate. Water is the primary limitation to productivity in these forests. Many forest soils in...

A field guide for the identification of invasive plants in southern forests

Treesearch

James H. Miller; Erwin B. Chambliss; Nancy J. Loewenstein

2010-01-01

Invasions of nonnative plants into forests of the Southern United States continue to go unchecked and only partially unmonitored. These infestations increasingly erode forest productivity, hindering forest use and management activities, and degrading diversity and wildlife habitat. Often called nonnative, exotic, nonindigenous, alien, or noxious weeds, they occur as...

Floristic conservation value, nested understory floras, and the development of second-growth forest.

PubMed

Spyreas, Greg; Matthews, Jeffrey W

2006-08-01

Nestedness analysis can reveal patterns of plant composition and diversity among forest patches. For nested floral assemblages, the plants occupying any one patch are a nested subset of the plants present in successively more speciose patches. Elimination of sensitive understory plants with human disturbance is one of several mechanisms hypothesized to generate nonrandom, nested floral distributions. Hypotheses explaining distributions of understory plants remain unsubstantiated across broad landscapes of varying forest types and disturbance histories. We sampled the vegetation of 51 floodplain and 55 upland forests across Illinois (USA) to examine how the diversity, composition, and nestedness of understory floras related to their overstory growth and structure (basal area), and their overall floristic conservation value (mean C). We found that plant assemblages were nested with respect to site species richness, such that rare plants indicated diverse forests. Floras were also nested with respect to site mean C and basal area (BA). However, in an opposite pattern from what we had expected, floras of high-BA stands were nested subsets of those of low-BA stands. A set of early-successional plants restricted to low-BA stands, and more importantly, the absence of a set of true forest plants in high-BA stands, accounted for this pattern. Additionally, we observed a decrease in species richness with increasing BA. These results are consistent with the hypothesis that recovery of true forest plants does not occur concurrently with overstory regeneration following massive anthropogenic disturbance. Nestedness by site mean C indicates that high conservation value (conservative) plants co-occur in highly diverse stands; these forests are assumed to be less disturbed historically. Because site mean C was uncorrelated with BA, BA-neutral disturbances such as livestock usage are suggested as accounting for between-site differences in mean C. When considered individually, conservative plants were actually more likely to be found in low-BA stands (uplands only). This suggests that floras of historically more open-canopied oak-hickory uplands are being degraded by canopy closure from increasing density of "mesophytic, nonpyrogenic" trees. It also indirectly suggests that recent moderate logging is uncorrelated with floristic conservation values.

Early Pliocene vegetation distribution in Europe

NASA Astrophysics Data System (ADS)

Popescu, S.; Warny, S.; Suc, J.

2010-12-01

The Early Pliocene corresponds to a global warm climate documented by marine & terrestrial records. Reconstruction of climatic parameters, based on terrestrial proxies, indicate at European mid-latitudes a MAT higher of about 1-5°C than today and MAP higher of about 400-1000 mm. This global warm situation was interrupted between 4.7 - 4.5 Ma by a cooling event related to small fluctuations of the Antarctic ice-sheet that modify the floristic assemblages. according to pollen recors, the Northern Mediterranean area is characterized by dominance of arboreal pollen, suggesting a dense forest cover, on contrary to the Southern Mediterranean where herbs were prevalent, signifying a widespread development of open vegetation during the early Pliocene. Such a contrast in landscape between the North and the South of the Mediterranean is to be related to the latitudinal gradient in humidity. In the North Mediterranean area, the vegetation organization was also closely linked to the relief. Coastal plains were inhabited by Taxodiaceae swamps replaced in some places by marshes. With respect to the geographic position, several plant ecosystems can distinguished: (1) salt marshes, along the Atlantic coastline (zone A); (2) marshes mostly made of Cyperaceae evidenced on the Mediterranean coastline. Such juxtaposed assemblages resemble the modern vegetation of the Mississippi Delta and Florida. Peculiar vegetation assemblages characterize the Mediterranean coastal plains. In the southeastern Mediterranean region (Zone B), the open vegetation was composed by herbs including subdesertic elements. Mediterranean xerophytes are only numerically represented in the area of Tarragona and Sicily, their assemblage resemble the modern thermo-mediterranean formation. Close to the mountains (Zone C) vegetation is organized according to an altitudinal gradient. The low altitude vegetation was composed by Taxodiaceae (Sequoia) while Cathaya and Cedrus dominated the mid-altitude belt. Abies and Picea developed in higher altitude. The Eastern Europe vegetation (zone D) was characterized by coexistent warm-temperate forests and open ecosystems. Some megathermic and mega-mesothermic elements were persisting. Mediterranean xerophytes were indentified in few amounts in the Eastern Europe, showing a slight increase according to the latitudinal gradient. Site 380A (Black Sea) provides relatively high percentages of Artemisia growing in Anatolia, which increased again during the cooler periods. Anatolia probably represents the origin of the repeated steppe expansions which occurred in Europe at each glacial phase. Finally, the Nile region (zone E) documents the presence of savannah (composed mainly by Poaceae and Cyperaceae) including some subdesertic taxa. Nile riparian forests preserved several tropical-subtropical elements.

Soil Organic Carbon assessment on two different forest management

NASA Astrophysics Data System (ADS)

Fernández Minguillón, Alex; Sauras Yera, Teresa; Vallejo Calzada, Ramón

2017-04-01

Soil Organic Carbon assessment on two different forest management. A.F. Minguillón1, T. Sauras1, V.R: Vallejo1. 1 Departamento de Biología Evolutiva, Ecología y Ciencias Ambientales, Universidad de Barcelona, Avenida Diagonal 643, 03080 Barcelona, Spain. Soils from arid and semiarid zones are characterized by a low organic matter content from scarce plant biomass and it has been proposed that these soils have a big capacity to carbon sequestration. According to IPCC ARS WG2 (2014) report and WG3 draft, increase carbon storage in terrestrial ecosystems has been identified such a potential tool for mitigation and adaptation to climate change. In ecological restoration context improve carbon sequestration is considered a management option with multiple benefits (win-win-win). Our work aims to analyze how the recently developed restoration techniques contributed to increases in terrestial ecosystem carbon storage. Two restoration techniques carried out in the last years have been evaluated. The study was carried out in 6 localities in Valencian Community (E Spain) and organic horizons of two different restoration techniques were evaluated; slash brush and thinning Aleppo pine stands. For each technique, carbon stock and its physical and chemical stability has been analysed. Preliminary results point out restoration zones acts as carbon sink due to (1) the relevant necromass input produced by slash brush increases C stock on the topsoil ;(2) Thinning increase carbon accumulation in vegetation.

Variation in Vegetation Structure and Soil Properties, and the Relation Between Understory Plants and Environmental Variables Under Different Phyllostachys pubescens Forests in Southeastern China

NASA Astrophysics Data System (ADS)

Zhang, Changshun; Xie, Gaodi; Fan, Shaohui; Zhen, Lin

2010-04-01

Biodiversity maintenance and soil improvement are key sustainable forestry objectives. Research on the effects of bamboo forest management on plant diversity and soil properties are therefore necessary in bamboo-growing regions, such as southeastern China’s Shunchang County, that have not been studied from this perspective. We analyzed the effects of different Phyllostachys pubescens proportions in managed forests on vegetation structure and soil properties using pure Cunninghamia lanceolata forests as a contrast, and analyzed the relation between understory plants and environmental variables (i.e., topography, stand and soil characteristics) by canonical correspondence analysis (CCA). The forest with 80% P. pubescens and 20% hardwoods (such as Phoebe bournei, Jatropha curcas, Schima superba) maintained the highest plant diversity and best soil properties, with significantly higher plant diversity than the C. lanceolata forest, and better soil physicochemical and biological properties. The distribution of understory plants is highly related to environmental factors. Silvicultural disturbance strongly influenced the ability of different bamboo forests to maintain biodiversity and soil quality under extensive management, and the forest responses to management were consistent with the intermediate-disturbance hypothesis (i.e., diversity and soil properties were best at intermediate disturbance levels). Our results suggest that biodiversity maintenance and soil improvement are important management goals for sustainable bamboo management. To achieve those objectives, managers should balance the inputs and outputs of nutrients and protect understory plants by using appropriate fertilizer (e.g., organic fertilizer), adjusting stand structure, modifying utilization model and the harvest time, and controlling the intensity of culms and shoots harvests.

Darcy's law predicts widespread forest mortality under climate warming

NASA Astrophysics Data System (ADS)

McDowell, Nathan G.; Allen, Craig D.

2015-07-01

Drought and heat-induced tree mortality is accelerating in many forest biomes as a consequence of a warming climate, resulting in a threat to global forests unlike any in recorded history. Forests store the majority of terrestrial carbon, thus their loss may have significant and sustained impacts on the global carbon cycle. We use a hydraulic corollary to Darcy’s law, a core principle of vascular plant physiology, to predict characteristics of plants that will survive and die during drought under warmer future climates. Plants that are tall with isohydric stomatal regulation, low hydraulic conductance, and high leaf area are most likely to die from future drought stress. Thus, tall trees of old-growth forests are at the greatest risk of loss, which has ominous implications for terrestrial carbon storage. This application of Darcy’s law indicates today’s forests generally should be replaced by shorter and more xeric plants, owing to future warmer droughts and associated wildfires and pest attacks. The Darcy’s corollary also provides a simple, robust framework for informing forest management interventions needed to promote the survival of current forests. Given the robustness of Darcy’s law for predictions of vascular plant function, we conclude with high certainty that today’s forests are going to be subject to continued increases in mortality rates that will result in substantial reorganization of their structure and carbon storage.

Darcy’s law predicts widespread forest mortality under climate warming

USGS Publications Warehouse

McDowell, Nate G.; Allen, Craig D.

2015-01-01

Drought and heat-induced tree mortality is accelerating in many forest biomes as a consequence of a warming climate, resulting in a threat to global forests unlike any in recorded history. Forests store the majority of terrestrial carbon, thus their loss may have significant and sustained impacts on the global carbon cycle. We use a hydraulic corollary to Darcy’s law, a core principle of vascular plant physiology, to predict characteristics of plants that will survive and die during drought under warmer future climates. Plants that are tall with isohydric stomatal regulation, low hydraulic conductance, and high leaf area are most likely to die from future drought stress. Thus, tall trees of old-growth forests are at the greatest risk of loss, which has ominous implications for terrestrial carbon storage. This application of Darcy’s law indicates today’s forests generally should be replaced by shorter and more xeric plants, owing to future warmer droughts and associated wildfires and pest attacks. The Darcy’s corollary also provides a simple, robust framework for informing forest management interventions needed to promote the survival of current forests. Given the robustness of Darcy’s law for predictions of vascular plant function, we conclude with high certainty that today’s forests are going to be subject to continued increases in mortality rates that will result in substantial reorganization of their structure and carbon storage.

Quantifying the fire regime distributions for severity in Yosemite National Park, California, USA

USGS Publications Warehouse

Thode, Andrea E.; van Wagtendonk, Jan W.; Miller, Jay D.; Quinn, James F.

2011-01-01

This paper quantifies current fire severity distributions for 19 different fire-regime types in Yosemite National Park, California, USA. Landsat Thematic Mapper remote sensing data are used to map burn severity for 99 fires (cumulatively over 97 000 ha) that burned in Yosemite over a 20-year period. These maps are used to quantify the frequency distributions of fire severity by fire-regime type. A classification is created for the resultant distributions and they are discussed within the context of four vegetation zones: the foothill shrub and woodland zone; the lower montane forest zone; the upper montane forest zone and the subalpine forest zone. The severity distributions can form a building block from which to discuss current fire regimes across the Sierra Nevada in California. This work establishes a framework for comparing the effects of current fires on our landscapes with our notions of how fires historically burned, and how current fire severity distributions differ from our desired future conditions. As this process is refined, a new set of information will be available to researchers and land managers to help understand how fire regimes have changed from the past and how we might attempt to manage them in the future.

Aboveground-belowground biodiversity linkages differ in early and late successional temperate forests

PubMed Central

Li, Hui; Wang, Xugao; Liang, Chao; Hao, Zhanqing; Zhou, Lisha; Ma, Sam; Li, Xiaobin; Yang, Shan; Yao, Fei; Jiang, Yong

2015-01-01

Understanding ecological linkages between above- and below-ground biota is critical for deepening our knowledge on the maintenance and stability of ecosystem processes. Nevertheless, direct comparisons of plant-microbe diversity at the community level remain scarce due to the knowledge gap between microbial ecology and plant ecology. We compared the α- and β- diversities of plant and soil bacterial communities in two temperate forests that represented early and late successional stages. We documented different patterns of aboveground-belowground diversity relationships in these forests. We observed no linkage between plant and bacterial α-diversity in the early successional forest, and even a negative correlation in the late successional forest, indicating that high bacterial α-diversity is not always linked to high plant α-diversity. Beta-diversity coupling was only found at the late successional stage, while in the early successional forest, the bacterial β-diversity was closely correlated with soil property distances. Additionally, we showed that the dominant competitive tree species in the late successional forest may play key roles in driving forest succession by shaping the soil bacterial community in the early successional stage. This study sheds new light on the potential aboveground-belowground linkage in natural ecosystems, which may help us understand the mechanisms that drive ecosystem succession. PMID:26184121

Ungulates increase forest plant species richness to the benefit of non-forest specialists.

PubMed

Boulanger, Vincent; Dupouey, Jean-Luc; Archaux, Frédéric; Badeau, Vincent; Baltzinger, Christophe; Chevalier, Richard; Corcket, Emmanuel; Dumas, Yann; Forgeard, Françoise; Mårell, Anders; Montpied, Pierre; Paillet, Yoan; Picard, Jean-François; Saïd, Sonia; Ulrich, Erwin

2018-02-01

Large wild ungulates are a major biotic factor shaping plant communities. They influence species abundance and occurrence directly by herbivory and plant dispersal, or indirectly by modifying plant-plant interactions and through soil disturbance. In forest ecosystems, researchers' attention has been mainly focused on deer overabundance. Far less is known about the effects on understory plant dynamics and diversity of wild ungulates where their abundance is maintained at lower levels to mitigate impacts on tree regeneration. We used vegetation data collected over 10 years on 82 pairs of exclosure (excluding ungulates) and control plots located in a nation-wide forest monitoring network (Renecofor). We report the effects of ungulate exclusion on (i) plant species richness and ecological characteristics, (ii) and cover percentage of herbaceous and shrub layers. We also analyzed the response of these variables along gradients of ungulate abundance, based on hunting statistics, for wild boar (Sus scrofa), red deer (Cervus elaphus) and roe deer (Capreolus capreolus). Outside the exclosures, forest ungulates maintained higher species richness in the herbaceous layer (+15%), while the shrub layer was 17% less rich, and the plant communities became more light-demanding. Inside the exclosures, shrub cover increased, often to the benefit of bramble (Rubus fruticosus agg.). Ungulates tend to favour ruderal, hemerobic, epizoochorous and non-forest species. Among plots, the magnitude of vegetation changes was proportional to deer abundance. We conclude that ungulates, through the control of the shrub layer, indirectly increase herbaceous plant species richness by increasing light reaching the ground. However, this increase is detrimental to the peculiarity of forest plant communities and contributes to a landscape-level biotic homogenization. Even at population density levels considered to be harmless for overall plant species richness, ungulates remain a conservation issue for plant community composition. ©2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Monitoring mangrove forests after aquaculture abandonment using time series of very high spatial resolution satellite images: A case study from the Perancak estuary, Bali, Indonesia.

PubMed

Proisy, Christophe; Viennois, Gaëlle; Sidik, Frida; Andayani, Ariani; Enright, James Anthony; Guitet, Stéphane; Gusmawati, Niken; Lemonnier, Hugues; Muthusankar, Gowrappan; Olagoke, Adewole; Prosperi, Juliana; Rahmania, Rinny; Ricout, Anaïs; Soulard, Benoit; Suhardjono

2018-06-01

Revegetation of abandoned aquaculture regions should be a priority for any integrated coastal zone management (ICZM). This paper examines the potential of a matchless time series of 20 very high spatial resolution (VHSR) optical satellite images acquired for mapping trends in the evolution of mangrove forests from 2001 to 2015 in an estuary fragmented into aquaculture ponds. Evolution of mangrove extent was quantified through robust multitemporal analysis based on supervised image classification. Results indicated that mangroves are expanding inside and outside ponds and over pond dykes. However, the yearly expansion rate of vegetation cover greatly varied between replanted ponds. Ground truthing showed that only Rhizophora species had been planted, whereas natural mangroves consist of Avicennia and Sonneratia species. In addition, the dense Rhizophora plantations present very low regeneration capabilities compared with natural mangroves. Time series of VHSR images provide comprehensive and intuitive level of information for the support of ICZM. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simulations of forest mortality in Colorado River basin

NASA Astrophysics Data System (ADS)

Wei, L.; Xu, C.; Johnson, D. J.; Zhou, H.; McDowell, N.

2017-12-01

The Colorado River Basin (CRB) had experienced multiple severe forest mortality events under the recent changing climate. Such forest mortality events may have great impacts on ecosystem services and water budget of the watershed. It is hence important to estimate and predict the forest mortality in the CRB with climate change. We simulated forest mortality in the CRB with a model of plant hydraulics within the FATES (the Functionally Assembled Terrestrial Ecosystem Simulator) coupled to the DOE Earth System model (ACME: Accelerated Climate Model of Energy) at a 0.5 x 0.5 degree resolution. Moreover, we incorporated a stable carbon isotope (δ13C) module to ACME(FATE) and used it as a new predictor of forest mortality. The δ13C values of plants with C3 photosynthetic pathway (almost all trees are C3 plants) can indicate the water stress plants experiencing (the more intensive stress, the less negative δ13C value). We set a δ13C threshold in model simulation, above which forest mortality initiates. We validate the mortality simulations with field data based on Forest Inventory and Analysis (FIA) data, which were aggregated into the same spatial resolution as the model simulations. Different mortality schemes in the model (carbon starvation, hydraulic failure, and δ13C) were tested and compared. Each scheme demonstrated its strength and the plant hydraulics module provided more reliable simulations of forest mortality than the earlier ACME(FATE) version. Further testing is required for better forest mortality modelling.

Characterizing the Status (Disturbed, Hybrid or Novel) of Swamp Forest Fragments in a Caribbean Ramsar Wetland: The Impact of Anthropogenic Degradation and Invasive Plant Species.

PubMed

Prospere, Kurt; McLaren, Kurt P; Wilson, Byron

2016-10-01

The last remaining Amazonian-type swamp forest fragments in Black River Lower Morass, Jamaica, have been subjected to a myriad of anthropogenic disturbances, compounded by the establishment and spread of several invasive plant species. We established 44 permanent sample plots (covering 3.92 ha) across 10 of these swamp forest fragments and sampled all non-woody plants and all trees ≥2 cm DBH found in the plots. These data were used to (1) identify thresholds of hybridity and novelty, (2) derive several diversity and structural descriptors used to characterize the swamp forest fragments and (3) identify possible indicators of anthropogenic degradation. These were incorporated into a framework and used to determine the status of the swamp forest fragments so that appropriate management and conservation measures can be implemented. We recorded 43 woody plant species (9 endemic, 28 native and 4 non-native) and 21 non-tree species. The composition and structure of all the patches differed significantly due to the impact of the herbaceous invasive plant Alpinia allughas, the presence and diversity of other non-native plants, and differing intensities of anthropogenic disturbance (e.g., burning, cutting and harvesting of non-timber forest products). We ranked forest patches along a continuum representing deviations from a historical proxy (least disturbed) swamp forest to those with dramatically altered structural and floristic attributes (=novel swamp forests). Only one fragment overrun with A. allughas was classified as novel. If effective conservation and management does not come to the BRLM, the remaining swamp forest fragments appear doomed to further degradation and will soon disappear altogether.

Characterizing the Status (Disturbed, Hybrid or Novel) of Swamp Forest Fragments in a Caribbean Ramsar Wetland: The Impact of Anthropogenic Degradation and Invasive Plant Species

NASA Astrophysics Data System (ADS)

Prospere, Kurt; McLaren, Kurt P.; Wilson, Byron

2016-10-01

The last remaining Amazonian-type swamp forest fragments in Black River Lower Morass, Jamaica, have been subjected to a myriad of anthropogenic disturbances, compounded by the establishment and spread of several invasive plant species. We established 44 permanent sample plots (covering 3.92 ha) across 10 of these swamp forest fragments and sampled all non-woody plants and all trees ≥2 cm DBH found in the plots. These data were used to (1) identify thresholds of hybridity and novelty, (2) derive several diversity and structural descriptors used to characterize the swamp forest fragments and (3) identify possible indicators of anthropogenic degradation. These were incorporated into a framework and used to determine the status of the swamp forest fragments so that appropriate management and conservation measures can be implemented. We recorded 43 woody plant species (9 endemic, 28 native and 4 non-native) and 21 non-tree species. The composition and structure of all the patches differed significantly due to the impact of the herbaceous invasive plant Alpinia allughas, the presence and diversity of other non-native plants, and differing intensities of anthropogenic disturbance (e.g., burning, cutting and harvesting of non-timber forest products). We ranked forest patches along a continuum representing deviations from a historical proxy (least disturbed) swamp forest to those with dramatically altered structural and floristic attributes (=novel swamp forests). Only one fragment overrun with A. allughas was classified as novel. If effective conservation and management does not come to the BRLM, the remaining swamp forest fragments appear doomed to further degradation and will soon disappear altogether.

Hybridization between mouse lemurs in an ecological transition zone in southern Madagascar.

PubMed

Gligor, M; Ganzhorn, J U; Rakotondravony, D; Ramilijaona, O R; Razafimahatratra, E; Zischler, H; Hapke, A

2009-02-01

Hybrid zones in ecotones can be useful model systems for the study of evolutionary processes that shape the distribution and discreteness of species. Such studies could be important for an improved understanding of the complex biogeography of Madagascar, which is renowned for its outstanding degree of small-scale endemism. Certain forest remnants in central Madagascar indicate that transitional corridors across the island could have connected microendemics in different forest types in the past. Evolutionary processes in such corridors are difficult to study because most of these corridors have disappeared due to deforestation in central Madagascar. We studied a hybrid zone in one of the few remaining ecotonal corridors between dry and humid forests in Madagascar, which connects two species of mouse lemurs, Microcebus griseorufus in dry spiny forest and Microcebus murinus in humid littoral forest. We sampled 162 mouse lemurs at nine sites across this boundary. Morphometric analyses revealed intermediate morphotypes of many individuals in transitional habitat. Bayesian clustering of microsatellite genotypes and assignment tests yielded evidence for a mixed ancestry of mouse lemurs in the ecotone, where we also observed significant linkage disequilibria and heterozygote deficiency. In contrast to these observations, mitochondrial haplotypes displayed a sharply delimited boundary at the eastern edge of spiny forest, which was noncoincident with the signals from microsatellite data. Among several alternative scenarios, we propose asymmetric nuclear introgression due to male-biased dispersal, divergent environmental selection, and an expansion of dry spiny forest in the course of aridification as a probable explanation of our observations.

The long-term effects of planting and harvesting on secondary forest dynamics under climate change in northeastern China

PubMed Central

Yao, Jing; He, Xingyuan; He, Hongshi; Chen, Wei; Dai, Limin; Lewis, Bernard J.; Yu, Lizhong

2016-01-01

Unlike the virgin forest in the Changbaishan Nature Reserve in northeastern China, little research on a landscape scale has been conducted on secondary forests in the region under conditions of a warming climate. This research was undertaken in the upper Hun River region where the vegetation is representative of the typical secondary forest of northeastern China. The spatially explicit forest landscape model LANDIS was utilized to simulate the responses of forest restoration dynamics to anthropogenic disturbance (planting and harvesting) and evaluate the difference of the restoration process under continuation of current climatic conditions and climate warming. The results showed that: (1) The interaction of planting and harvesting has organizational scale effects on the forest. The combination of planting and harvesting policies has significant effects on the overall forest but not on individual species. (2) The area expansion of the historically dominant species Pinus koraiensis is less under climate warming than under continuation of current climatic conditions. These suggests that we should carefully take historically dominant species as the main focus for forest restoration, especially when they are near their natural distribution boundary, because they are probably less capable of successfully adapting to climate change. PMID:26725308

The long-term effects of planting and harvesting on secondary forest dynamics under climate change in northeastern China.

PubMed

Yao, Jing; He, Xingyuan; He, Hongshi; Chen, Wei; Dai, Limin; Lewis, Bernard J; Yu, Lizhong

2016-01-04

Unlike the virgin forest in the Changbaishan Nature Reserve in northeastern China, little research on a landscape scale has been conducted on secondary forests in the region under conditions of a warming climate. This research was undertaken in the upper Hun River region where the vegetation is representative of the typical secondary forest of northeastern China. The spatially explicit forest landscape model LANDIS was utilized to simulate the responses of forest restoration dynamics to anthropogenic disturbance (planting and harvesting) and evaluate the difference of the restoration process under continuation of current climatic conditions and climate warming. The results showed that: (1) The interaction of planting and harvesting has organizational scale effects on the forest. The combination of planting and harvesting policies has significant effects on the overall forest but not on individual species. (2) The area expansion of the historically dominant species Pinus koraiensis is less under climate warming than under continuation of current climatic conditions. These suggests that we should carefully take historically dominant species as the main focus for forest restoration, especially when they are near their natural distribution boundary, because they are probably less capable of successfully adapting to climate change.

Root water uptake and lateral interactions among root systems in a temperate forest

NASA Astrophysics Data System (ADS)

Agee, E.; He, L.; Bisht, G.; Gough, C. M.; Couvreur, V.; Matheny, A. M.; Bohrer, G.; Ivanov, V. Y.

2016-12-01

A growing body of research has highlighted the importance of root architecture and hydraulic properties to the maintenance of the transpiration stream under water limitation and drought. Detailed studies of single plant systems have shown the ability of root systems to adjust zones of uptake due to the redistribution of local water potential gradients, thereby delaying the onset of stress under drying conditions. An open question is how lateral interactions and competition among neighboring plants impact individual and community resilience to water stress. While computational complexity has previously hindered the implementation of microscopic root system structure and function in larger scale hydrological models, newer hybrid approaches allow for the resolution of these properties at the plot scale. Using a modified version of the PFLOTRAN model, which represents the 3-D physics of variably saturated soil, we model root water uptake in a one-hectare temperate forest plot under natural and synthetic forcings. Two characteristic hydraulic architectures, tap roots and laterally sprawling roots, are implemented in an ensemble of simulations. Variations of root architecture, their hydraulic properties, and degree of system interactions produce variable local response to water limitation and provide insights on individual and community response to changing meteorological conditions. Results demonstrate the ability of interacting systems to shift areas of active uptake based on local gradients, allowing individuals to meet water demands despite competition from their peers. These results further illustrate how inter- and intra-species variations in root properties may influence not only individual response to water stress, but also help quantify the margins of resilience for forest ecosystems under changing climate.

Characterizing Hydrological Processes in Vadose Zone by Direct Infiltration Water Sampling.

NASA Astrophysics Data System (ADS)

Mori, Y.; Higashi, N.; Somura, H.; Takeda, I.; Inoue, M.

2007-12-01

These days, planted forest mountainside was roughly maintained due to the population descent and small birth rate. Because thinning operation would delayed, forest was always dark and floor weed was rare. Management induced non point source pollution like surface soil erosion was suspected, however, we could not approach to the source with the stream water analysis. Therefore, direct soil water sampling device using glass fiber capillary force was developed to examine hydrological processes in watershed. In our design, water was collected just by the capillary force and let the excess water down through so that infiltration water was truly sampled and solute concentration kept the same quality as in soil water. The experiment was conducted at two neighboring Japanese cedar planted forest under different management, i.e., south slope was roughly maintained and west slope was well maintained by thinning operation. Load discharges were higher in south slope and lower in west slope. Infiltration water analysis revealed that ion concentration was gradually decreased at west slope, however in south slope, it dropped to lower level in soil water and increased again in stream water. The trend showed that soil buffering function was poor in south slope. Actually, disk permeameter survey revealed that hydraulic conductivity was small in south slope; TOC and biological activity were lower. This entire soil environment explained the water environmental differences in stream water. Because changes in soil environment affects water environment in the future, monitoring or examination of soil environment was considered as preventive measure for environmentally sound water and solute circulation in watershed.

Susceptibility of burned black spruce (Picea mariana) forests to non-native plant invasions in interior Alaska

Treesearch

Katie V. Spellman; Christa P.H. Mulder; Teresa N. Hollingsworth

2014-01-01

As climate rapidly warms at high-latitudes, the boreal forest faces the simultaneous threats of increasing invasive plant abundances and increasing area burned by wildfire. Highly flammable and widespread black spruce (Picea mariana) forest represents a boreal habitat that may be increasingly susceptible to non-native plant invasion. This study assess the role of burn...

Aquatic fate of aerially applied hexazinone and terbuthylazine in a New Zealand planted forest

Treesearch

Brenda R. Baillie; Daniel G. Neary; Stefan Gous; Carol A. Rolando

2015-01-01

Herbicides are used to control competing vegetation during tree establishment, and are often critical to the productivity and economic viability of a planted forest crop. Despite increasing public concern over herbicide use in planted forests and potential impact on the environment, there is limited information on the aquatic fate of many of these herbicides when...

A comparison of conifers planted on the Hemlock Experimental Forest.

Treesearch

Norman P. Worthington

1955-01-01

Test plantings have been made on the Hemlock Experimental Forest in cooperation with the St. Regis Paper Company to test suitability of several native conifers for planting on heavy bracken and brush-covered Site II areas typical of the western Olympic Peninsula. In the spring of 1950, 2,500 Douglas-fir seedlings from the Forest Industries Tree Nursery at Nisqually...

Tree planting by small producers in the tropics: A comparative study of Brazil and Panama.

Treesearch

Cynthia S. Simmons; Robert T. Walker; Charles H. Wood

2002-01-01

Forest regrowth is a notable phenomenon across the tropical forest latitudes. Such reforestation takes place in the wake of land abandonment, occurs cyclically in a rotational agricultural system, and may result from the deliberate planting of trees by farmers. Although less extensive than successional forest regeneration, tree planting by small farmers can have...

Plant recruitment in a northern Arizona ponderosa pine forest: Testing seed- and leaf litter-limitation hypotheses (P-53)

Treesearch

Scott R. Abella

2008-01-01

Seed availability and leaf litter limit plant establishment in some ecosystems. To evaluate the hypothesis that these factors limit understory plant recruitment in Pinus ponderosa forests, I conducted a seeding and litter removal experiment at six thinned sites in the Fort Valley Experimental Forest, northern Arizona. Experimental seeding of four native species (...

Plant recruitment in a northern Arizona ponderosa pine forest: Testing seed- and leaf litter-limitation hypotheses

Treesearch

Scott R. Abella

2008-01-01

Seed availability and leaf litter limit plant establishment in some ecosystems. To evaluate the hypothesis that these factors limit understory plant recruitment in Pinus ponderosa forests, I conducted a seeding and litter removal experiment at six thinned sites in the Fort Valley Experimental Forest, northern Arizona. Experimental seeding of four native species (

Tree diversity promotes insect herbivory in subtropical forests of south-east China.

PubMed

Schuldt, Andreas; Baruffol, Martin; Böhnke, Martin; Bruelheide, Helge; Härdtle, Werner; Lang, Anne C; Nadrowski, Karin; von Oheimb, Goddert; Voigt, Winfried; Zhou, Hongzhang; Assmann, Thorsten; Fridley, Jason

2010-07-01

1.Insect herbivory can strongly affect ecosystem processes, and its relationship with plant diversity is a central topic in biodiversity-functioning research. However, very little is known about this relationship from complex ecosystems dominated by long-lived individuals, such as forests, especially over gradients of high plant diversity.2.We analysed insect herbivory on saplings of 10 tree and shrub species across 27 forest stands differing in age and tree species richness in an extraordinarily diverse subtropical forest ecosystem in China. We tested whether plant species richness significantly influences folivory in these highly diverse forests or whether other factors play a more important role at such high levels of phytodiversity.3.Leaf damage was assessed on 58 297 leaves of 1284 saplings at the end of the rainy season in 2008, together with structural and abiotic stand characteristics.4.Species-specific mean damage of leaf area ranged from 3% to 16%. Herbivory increased with plant species richness even after accounting for potentially confounding effects of stand characteristics, of which stand age-related aspects most clearly covaried with herbivory. Intraspecific density dependence or other abiotic factors did not significantly influence overall herbivory across forest stands.5.Synthesis.The positive herbivory-plant diversity relationship indicates that effects related to hypotheses of resource concentration, according to which a reduction in damage by specialized herbivores might be expected as host plant concentration decreases with increasing plant diversity, do not seem to be major determinants for overall herbivory levels in our phytodiverse subtropical forest ecosystem. We discuss the potential role of host specificity of dominant herbivores, which are often expected to show a high degree of specialization in many (sub)tropical forests. In the forest system we studied, a much higher impact of polyphagous species than traditionally assumed might explain the observed patterns, as these species can profit from a broad dietary mix provided by high plant diversity. Further testing is needed to experimentally verify this assumption.

Vascular epiphytes of the Atlantic Forest in the Sinos River basin, state of Rio Grande do Sul, Brazil: richness, floristic composition and community structure.

PubMed

Barbosa, M D; Becker, D F P; Cunha, S; Droste, A; Schmitt, J L

2015-05-01

The Atlantic Forest, which has a vast epiphytic richness, is a priority area for preservation, listed as one of the five most important world hotspots. Vascular epiphyte richness, composition and community structure were studied in two fragments, one of the ombrophilous (29º43'42"S and 50º22'00"W) and the other of the seasonal (29º40'54"S and 51º06'56"W) forest, both belonging to the Atlantic Forest biome in the Sinos River basin, Rio Grande do Sul, Brazil. In each fragment, 40 trees, divided into four ecological zones, were analyzed. In each zone, the occurrence of the species was recorded, and the importance value of each species was calculated according to the frequency of phorophytes and intervals, and cover scores. The Shannon index was calculated for the two communities. In the fragment of the ombrophilous forest (F1), 30 epiphytic species were recorded, and in the seasonal forest (F2), 25. The highest importance value was found for Microgramma squamulosa (Kaulf.) de la Sota in both fragments. The diversity indexes for F1 (H'=2.72) and F2 (H'=2.55) were similar and reflected the subtropical location of the areas. The decrease in mean richness in both fragments in zone 3 (internal crown) to zone 4 (external crown) may be associated with time and space availability for epiphyte occupation and microclimate variations. Exclusive species were found in the areas, which suggest that a greater number of preserved fragments may result in a greater number of preserved epiphytic species in the Sinos River basin.

Experimental and numerical investigations of the geometry influence on gas accumulation using a V-shaped forest model

NASA Astrophysics Data System (ADS)

Coudour, Bruno; Chetehouna, Khaled; Conan, Boris; Aubrun, Sandrine; Kaiss, Ahmed; Garo, Jean-Pierre

2016-09-01

Accumulation of gas inside a valley exposed to crosswind is experimented in this paper to extrapolate it to a case of a forest fire approaching a thalweg. Experimentations were done inside a wind tunnel using a 1/400 forest model configured as a valley with two different internal angles. The forest was modelled by mesh cylinders so that a parallel is possible with a real forest thanks to similitude laws. Gas emission was ensured by 400 tubes introduced inside the cylinders and supplied with ethane which acted as a tracer. The 400 tubes were divided into four independent parts of 100 tubes, inside and outside the valley, to be able to study independently the influence of the different zones of the forest model on the gas accumulation. We focused on the measurements of velocity by Laser-Doppler Velocimetry (LDV) and concentration with a Flame Ionization Detector (FID) to visualise the flow and quantify the accumulation of ethane. Analysing velocity, turbulence and concentration, a stagnation point was observed in the thalweg for the flattest valley and a recirculation zone for the deepest one where gas accumulation reached up to four times the concentration measured outside the valley due to airflow. The study of the influence of the different emission zones showed that gas accumulation mainly comes from the zones inside the valley. All these data permitted us to validate a numerical modelling which will enable us to study more cases, varying above all gas density but also choosing more valley angles and configurations. Another interest of the numerical model is the possibility of adding a thermal model.

Comparing Forest/Nonforest Classifications of Landsat TM Imagery for Stratifying FIA Estimates of Forest Land Area

Treesearch

Mark D. Nelson; Ronald E. McRoberts; Greg C. Liknes; Geoffrey R. Holden

2005-01-01

Landsat Thematic Mapper (TM) satellite imagery and Forest Inventory and Analysis (FIA) plot data were used to construct forest/nonforest maps of Mapping Zone 41, National Land Cover Dataset 2000 (NLCD 2000). Stratification approaches resulting from Maximum Likelihood, Fuzzy Convolution, Logistic Regression, and k-Nearest Neighbors classification/prediction methods were...

Ecological classification and management characteristics of montane forest land in southwestern Washington.

Treesearch

D.G. Brockway; C. Topik

1984-01-01

Vegetation, soil, and site data werecollectedthroughout the forested portion of the Pacific silver fir and mountain hemlock zones of the Gifford Pinchot National Forest as part of the Forest Service program to develop anecoIogicallybasedplant association classification system for the Pacific Northwest Region. The major objective of sampling was to include a wide...

How does conversion from peat swamp forest to oil palm plantation affect emissions of nitrous oxide from the soil? A case study in Jambi, Indonesia

NASA Astrophysics Data System (ADS)

Hartill, Jodie; Hergoualc'h, Kristell; Comeau, Louis-Pierre; Jo, Smith; Lou, Verchot

2017-04-01

Half of the peatlands across Peninsular Malaysia, Borneo and Sumatra are 'managed'. Conversion of peat swamp forest to workable oil palm plantation requires a drastic, potentially irreversible, change to the landscape, to which fertilizers are then routinely applied. A combination of these factors is now widely thought to increase soil nitrous oxide (N2O) emissions, although there is high uncertainty due to gaps in the knowledge, both regionally and nationally. Despite the widespread use of fertilizers in plantations on peats, studies observing their effects remain very limited. Therefore, there is a need for in situ studies to evaluate how environmental parameters (edaphic properties, climate, soil moisture and N availability indicators) influence soil emissions. This 18 month study was located in plots local to each other, representing the start, intermediate and end of the land conversion process; namely mixed peat swamp forest, drained and logged forest and industrial oil palm plantation. Spatial variability was taken into account by differentiating the hollows and hummocks in the mixed peat swamp forest, and the fertilized zone and the zone without fertilizer addition in the oil palm plantation. Gas samples were collected each month from static chambers at the same time as key environmental parameters were measured. Intensive sampling was performed during a 35 day period following two fertilizer applications, in which urea was applied to palms at rates of 0.5 and 1 kg urea palm-1. Soil N2O emissions (kg N ha-1 y-1 ± SE) were low overall, but they were greater in the oil palm plantation (0.8 ± 0.1) than in the mixed peat swamp forest (0.3 ± 0.0) and the drained/logged forest (0.2 ± 0.0). In the mixed peat swamp forest, monthly average fluxes of N2O (g N ha-1 d-1 ± SE) were similar in the hollows (0.6 ± 0.2) and the hummocks (0.3 ± 0.1), whereas in the oil palm plantation they were consistently higher in the zone without fertilizer (2.5 ± 0.4) than in the fertilized zone (0.5 ± 0.1), even after fertilizer application. In the fertilized zones, the N2O fluxes following the two fertilizer applications were 2.4 and 4.5 times higher respectively than fluxes observed in the absence of fertilizers. No change in emissions was observed in the neighboring unfertilized zone at the time of fertilizer application. Soil N2O emissions were related to changes in air and soil temperature in the mixed peat swamp forest, air temperature and water table depth in the drained and logged forest, and rainfall on the day of measurement in the oil palm plantation. This research confirms that peat forest conversion to oil palm plantation has negative consequences on the emissions of N2O. It also corroborates an increase in emission due to fertilizer application, with a magnitude comparable to the emission factor provided by the IPCC guidelines, but this is restricted to the limited area of fertilizer application.

Changes in necromass and nutrients on the forest floor of a palm floodplain forest in the Luquillo mountains of Puerto Rico.

Treesearch

ARIEL E. LUGO; JORGE L. FRANGI

2003-01-01

We studied changes that occurred between 1980 and 2000 in forest floor biomass (necromass+ biomass of herbaceous plants), nutrient stocks, and plant composition of a Prestoea montana floodplain forest. The forest was located in the Luquillo Mountains of Puerto Rico. Several storms and hurricanes passed near the study site during that period, the most severe being...

76 FR 75543 - Environmental Impacts Statements; Notice of Availability

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-02

... Profile Zones (DFPZs), Lassen National Forest, Almanor Ranger District, Plumas County, CA, Comment Period... Treatment Activities, Updated and New Information, Idaho Panhandle National Forests, Priest Lake Ranger... (937) 257-5899. EIS No. 20110403, Draft EIS, USFS, CA, Creeks II Forest Restoration Project, Proposal...

Invasive plants found in Louisiana’s forests, 2009 forest inventory and analysis factsheet

Treesearch

Sonja N. Oswalt; Christopher M. Oswalt

2012-01-01

Foresters and ecologists have noted the spread of nonnative invasive species onto U.S. forest land for decades. Despite soaring costs related to the management of and removal of invasive plants, and inestimable environmental impacts (e.g., altered soil chemistry, competition with native species, altered light environment; Pimentel and others 2005), nonnative invasive...

Sustaining Productivity of Planted Forests in the Gulf Coast Region

Treesearch

James P. Bamett; Allan E. Tiarks; Mary Anne Sword

2000-01-01

The forests of the Gulf Coastal Region provide the basis for its economic well-being. Because of the semitropical climate, abundant rainfall and availing topography, the nation's richest plant communities thrive. These forests are predominately privately owned. Millions of private landowners are committed to managing their forests for a broad array of values which...

Identification of sensitive parameters of a tropical forest in Southern Mexico to improve the understanding of C-band radar images

NASA Astrophysics Data System (ADS)

Monsivais-Huertero, A.; Jimenez-Escalona, J. C.; Ramos, J.; Zempoaltecatl-Ramirez, E.

2013-05-01

Forest areas cover the 32% of the Mexican territory. Due to their geographical location, Mexico presents heterogeneous climatic and topographic conditions. The country is divided into two different regions: an arid /semiarid zone (North) and a tropical/temperate zone (South). Due to the effects of climate change, Mexico has been affected in two ways. In the North, there has been a desertification of regions as result of the absence of rainfall and a low rate of soil moisture. On the other hand, in the South, there has been an increase in the intensity of rainfall causing serious flooding. Another effect is the excessive deforestation in Southern Mexico. The FAO has determined that Mexico could present one of the highest losses of forest areas mainly in temperate and subtropical ecosystems. The Biosphere Reserve of Calakmul is the protected area with the largest surface of tropical forest in Mexico. The Biosphere Reserve of Calakmul is located in the state of Campeche that the flora and fauna are being affected. The type of vegetation located in the reserve of Calakmul Biosphere is rainforest with high spatial density and highly heterogeneous due to multiple plant species and the impact of human activities in the area. The satellite remote sensing techniques becomes a very useful tool to monitor the area because a large area can be covered. To understand the radar images, the identification of sensitive parameters governing the radar signal is necessary. With the launch of the satellites Radarsat-2, ASAR-Envisat and ALOSPalSAR, significant progress has been done in the interpretation of satellite radar images. Directly applying physical models becomes a problem due to the large number of input parameters in the models, together with the difficulty in measuring these parameters in the field. The models developed so far have been applied and validated for homogeneous forests with low or average spatial density of trees. This is why it is recommended in a comprehensive validation of the models for heterogeneous forests with a high density of trees, such as Calakmul. This paper presents a methodology for identifying sensitive parameters governing the scenes backscatter vegetables reserve Calakmul Biosphere from a physical model.

Effects of hydrology on red mangrove recruits

USGS Publications Warehouse

Doyle, Thomas W.

2003-01-01

Coastal wetlands along the Gulf of Mexico have been experiencing significant shifts in hydrology and salinity levels over the past century as a result of changes in sea level and freshwater drainage patterns. Local land management in coastal zones has also impacted the hydrologic regimes of salt marshes and mangrove areas. Parks and refuges in south Florida that contain mangrove forests have, in some cases, been ditched or impounded to control mosquito outbreaks and to foster wildlife use. And while mangroves dominate the subtropical coastlines of Florida and thrive in saltwater environments, little is known about how they respond to changes in hydrology under managed or variable tidal conditions. USGS researchers designed a study to evaluate the basic hydrological requirements of mangroves so that their health and survival may be more effectively managed in controlled impoundments and restored wetlands. Mangroves are commonly found in the intertidal zone (between low and high tides) in a rather broad spectrum of hydrologic settings. Because they thrive at the interface of land and sea, mangroves are subject to changes in freshwater flow (flow rate, nutrients, pollutants) and to marine influences (sea-level rise, salinity). Salinity has long been recognized as a controlling factor that determines the health and distribution of mangrove forests. Field and experimental observations indicate that most mangrove species achieve their highest growth potential under brackish conditions (modest salinity) between 10 and 20 parts per thousand (ppt). Yet, if provided with available propagules, successful regeneration, and limited competition from other plants, then mangroves can survive and thrive in freshwater systems as well. Because little is known about the growthand survival patterns of mangrove species relative to changing hydrology, USGS scientists conducted greenhouse and field experiments to determine how flooded or drained patterns of hydrology would influence growth of the red mangrove, Rhizophora mangle (fig. 1). Red mangrove propagules (recruits) of select sizes and genotypes (i.e., genetically similar groups) were planted both in greenhouses and in the field. Seedling growth was monitored in both studies on a quarterly basis for over a year; measurements included shoot growth, seedling height, and a final harvest of plant biomass.

In vitro foliage susceptibility of canary islands laurel forests: a model for better understanding the ecology of Phytophthora ramorum

Treesearch

Eduardo Moralejo; Enrique Descals

2008-01-01

The tree species that dominate the cloud-zone forests of Macaronesia, the coastal redwoods of California, the Valdivian forests of Chile, the Atlantic forests of Brazil and the podocarp forests of New Zealand are all examples of paleoendemic species that once had a much wider distribution. They appear to owe their survival to the particular environmental conditions...

Fungi of Mount Babia Gora. 3: The indicating value of macromycetes in the forest associations

NASA Technical Reports Server (NTRS)

Bujakiewicz, A.

1984-01-01

The results of a mycological investigation of the forests of the upper mountain forest zone of Mt. Babia Gora and the synthetic characteristics of participation of macromycetes in all the forests studied are presented. Regularities and distinct connections were found in the occurrence of macromycetes on the background of various forest associations, differences in exposure, orography, climate, and changes induced by man.

36 CFR 13.912 - Kantishna area summer season firearm safety zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... firearm safety zone. 13.912 Section 13.912 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve General Provisions § 13.912 Kantishna area summer season firearm safety zone. What is prohibited? No one may fire a gun during the summer season in or across the Kantishna area firearm safety zone...

36 CFR 13.912 - Kantishna area summer season firearm safety zone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... firearm safety zone. 13.912 Section 13.912 Parks, Forests, and Public Property NATIONAL PARK SERVICE... Preserve General Provisions § 13.912 Kantishna area summer season firearm safety zone. What is prohibited? No one may fire a gun during the summer season in or across the Kantishna area firearm safety zone...

Spatial and temporal patterns of microclimates at an urban forest edge and their management implications.

PubMed

Li, Yingnan; Kang, Wanmo; Han, Yiwen; Song, Youngkeun

2018-01-23

Fragmented forests generate a variety of forest edges, leading to microclimates in the edge zones that differ from those in the forest interior. Understanding microclimatic variation is an important consideration for managers because it helps when making decisions about how to restrict the extent of edge effects. Thus, our study attempted to characterize the changing microclimate features at an urban forest edge located on Mt. Gwanak, Seoul, South Korea. We examined edge effects on air temperature, relative humidity, soil temperature, soil moisture, and photosynthetically active radiation (PAR) during the hottest three consecutive days in August 2016. Results showed that each variable responded differently to the edge effects. This urban forest edge had an effect on temporal changes at a diurnal scale in all microclimate variables, except soil moisture. In addition, all variables except relative humidity were significantly influenced by the edge effect up to 15 m inward from the forest boundary. The relative humidity fluctuated the most and showed the deepest extent of the edge effect. Moreover, the edge widths calculated from the relative humidity and air temperature both peaked in the late afternoon (16:00 h). Our findings provide a reference for forest managers in designing urban forest zones and will contribute to the conservation of fragmented forests in urban areas.

Evaluating land use and aboveground biomass dynamics in an oil palm-dominated landscape in Borneo using optical remote sensing

NASA Astrophysics Data System (ADS)

Singh, Minerva; Malhi, Yadvinder; Bhagwat, Shonil

2014-01-01

The focus of this study is to assess the efficacy of using optical remote sensing (RS) in evaluating disparities in forest composition and aboveground biomass (AGB). The research was carried out in the East Sabah region, Malaysia, which constitutes a disturbance gradient ranging from pristine old growth forests to forests that have experienced varying levels of disturbances. Additionally, a significant proportion of the area consists of oil palm plantations. In accordance with local laws, riparian forest (RF) zones have been retained within oil palm plantations and other forest types. The RS imagery was used to assess forest stand structure and AGB. Band reflectance, vegetation indicators, and gray-level co-occurrence matrix (GLCM) consistency features were used as predictor variables in regression analysis. Results indicate that the spectral variables were limited in their effectiveness in differentiating between forest types and in calculating biomass. However, GLCM based variables illustrated strong correlations with the forest stand structures as well as with the biomass of the various forest types in the study area. The present study provides new insights into the efficacy of texture examination methods in differentiating between various land-use types (including small, isolated forest zones such as RFs) as well as their AGB stocks.

A reconstruction of vegetation and paleohydrologycal changes from peatland in Kansk forest-steppe, Yenisei Siberia

NASA Astrophysics Data System (ADS)

Rodionova, Alexandra

2016-04-01

Peatlands are an important natural archive for past climatic changes. Climatic changes throughout the Holocene have been reconstructed from peat using a wide array of biological and other proxies. Many different proxy indicators can be derived from peat cores allowing for a multi-proxy approach to climatic reconstructions. Peat-based climatic and environmental reconstructions are currently available from many sites in Yenisei Siberia, mainly for its northern territories. The purpose of this paper is to study some features of peatland development and environmental reconstructions from the Holocene period in the south part of Yenisei Siberia (Kansk forest-steppe zone). The main method used in this research is macrofossil analysis. It can be used to reconstruct the development of local vegetation and surface wetness on peatlands. The macrofossil analysis in the peat resulted from the study of the vegetation in a particular place over a period of time, and it allowed the reconstruction of environmental changes that have occurred since the Late Glacial. Then we used ecological scales of moisture and reconstructed surface wetness for the entire period of the bog formation. Radiocarbon dating was carried out at Sobolev Institute of Geology and Mineralogy, Russian Academy of Sciences, Novosibirsk . Peatland "Pinchinskoye" was selected for investigation in Kansk forest-steppe. It is located on the right bank of the Yenisei River in the floodplain of Esaulovka River. Peat cores of 350 cm were selected in the southern part of the peatbog, including 225 cm of peat (with loam layers in the range of 90 to 135 cm), 75 cm of organic and mineral sapropel with the inclusion of fossil shells of mollusks and different plant macrofossils and 50 cm of the loam below. The process of peat accumulation dated back 8400 ± 140 years, which is the oldest date for the forest-steppe zone of Yenisei Siberia. The climate of Boreal period of the Holocene was chilly. Under these conditions, in the territory of the peatland "Pinchinskoye" there was a small lake. The birch forest with different grasses was growing along the banks of the lake. The lake level dropped significantly at the beginning of the Atlantic period around 7000 BP in a warm and dry climate. This launched the lake overgrowth and eutrophication. Birch forests and then spruce forests rich in herbs with green moss emerged in the peatland. An increase in moisture was recorded for the Sub-Boreal period (4900-2400) and, as a result, the prevalence of marsh communities with bog bean and fern. Increasing water level of rovers led to the spill and silting up of the bog surface in 2020 ± 60 BP at the beginning of the Sub-Atlantic period. After the decline of the water level, the process of peat accumulation continued and spread out throughout the whole trough flat. Sedge, cotton grass, sphagnum moss and green moss predominated in the composition of plant communities in Sub-Atlantic period, starting from 1500 BP. In the last 500 years, the peatland moved to the mesoeutrophic phase of development.

Classification of Snowfall Events and Their Effect on Canopy Interception Efficiency in a Temperate Montane Forest.

NASA Astrophysics Data System (ADS)

Roth, T. R.; Nolin, A. W.

2015-12-01

Forest canopies intercept as much as 60% of snowfall in maritime environments, while processes of sublimation and melt can reduce the amount of snow transferred from the canopy to the ground. This research examines canopy interception efficiency (CIE) as a function of forest and event-scale snowfall characteristics. We use a 4-year dataset of continuous meteorological measurements and monthly snow surveys from the Forest Elevation Snow Transect (ForEST) network that has forested and open sites at three elevations spanning the rain-snow transition zone to the upper seasonal snow zone. Over 150 individual storms were classified by forest and storm type characteristics (e.g. forest density, vegetation type, air temperature, snowfall amount, storm duration, wind speed, and storm direction). The between-site comparisons showed that, as expected, CIE was highest for the lower elevation (warmer) sites with higher forest density compared with the higher elevation sites where storm temperatures were colder, trees were smaller and forests were less dense. Within-site comparisons based on storm type show that this classification system can be used to predict CIE.Our results suggest that the coupling of forest type and storm type information can improve estimates of canopy interception. Understanding the effects of temperature and storm type in temperate montane forests is also valuable for future estimates of canopy interception under a warming climate.

Latitudinal variation in carbon storage can help predict changes in swamps affected by global warming

USGS Publications Warehouse

Middleton, Beth A.; McKee, Karen

2004-01-01

Plants may offer our best hope of removing greenhouse gases (gases that contribute to global warming) emitted to the atmosphere from the burning of fossil fuels. At the same time, global warming could change environments so that natural plant communities will either need to shift into cooler climate zones, or become extirpated (Prasad and Iverson, 1999; Crumpacker and others, 2001; Davis and Shaw, 2001). It is impossible to know the future, but studies combining field observation of production and modeling can help us make predictions about what may happen to these wetland communities in the future. Widespread wetland types such as baldcypress (Taxodium distichum) swamps in the southeastern portion of the United States could be especially good at carbon sequestration (amount of CO2 stored by forests) from the atmosphere. They have high levels of production and sometimes store undecomposed dead plant material in wet conditions with low oxygen, thus keeping gases stored that would otherwise be released into the atmosphere (fig. 1). To study the ability of baldcypress swamps to store carbon, our project has taken two approaches. The first analysis looked at published data to develop an idea (hypothesis) of how production levels change across a temperature gradient in the baldcypress region (published data study). The second study tested this idea by comparing production levels across a latitudinal range by using swamps in similar field conditions (ongoing carbon storage study). These studies will help us make predictions about the future ability of baldcypress swamps to store carbon in soil and plant biomass, as well as the ability of these forests to shift northward with global warming.

A Manual for the Identification of Invasive Plants in Southern Forests

Treesearch

Lewis Zimmerman

2012-01-01

This manual was created specifically for use by the U.S. Forest Service Southern Research Station (SRS), Forest Inventory and Analysis (FIA) field survey crews. The SRS FIA unit currently collects data on 33 invasive plants or groups across 13 States. The ability to accurately identify plant species in the field is a crucial component of monitoring a species’ presence...

Effects of high- and low-intensity fires on soil properties and plant growth in a Bolivian dry forest

Treesearch

Deborah K. Kennard; H.L. Gholz

2001-01-01

We compared soil nutrient availabiiity and soil physical properties among four treatments (high-intensity fire, low- intensity fire, plant removal, and harvesting gap) and a control (intact forest understory) over a period of 18 months in a tropical dry forest in Bolivia. The effect of treatments on plant growth was tested using a shade intolerant tree species (

Determining Solute Sources and Water Flowpaths in a Forested Headwater Catchment: Advances With the Ca-Sr-Ba Multi-tracer

NASA Astrophysics Data System (ADS)

Bullen, T. D.; Bailey, S. W.; McGuire, K. J.; Zimmer, M. A.; Ross, D. S.

2011-12-01

Determining solute sources and water flowpaths in catchments is of critical importance to development of models that effectively describe catchment function. For solutes in soil water and stream water, simple mass balance models that compare precipitation input to catchment outlet compositions can predict average mineral weathering contributions for the catchment as a whole, but fail to provide information about either variability of contributions from different portions of the catchment and different soil depths or processes such as ion exchange and biological cycling. In order to better understand how forested headwater catchments function, we are interpreting concentration and isotope ratios of the alkaline earth elements Ca, Sr and Ba in streamwater, groundwater, the soil ion exchange pool and plants in a hydropedologic context at the 41 hectare hydrologic reference catchment (Watershed 3) at the Hubbard Brook Experimental Forest, New Hampshire, USA. This forested headwater catchment consists of a beech-birch-maple-spruce forest growing on vertically- and laterally-developed Spodosols and Inceptisols formed on granitoid glacial till that mantles Paleozoic metamorphic bedrock. Across the watershed in terms of the soil ion exchange pool, the forest floor has high Sr/Ba and Ca/Sr ratios, mineral soils have intermediate Sr/Ba and low Ca/Sr, and relatively unweathered till in the C horizon has low Sr/Ba and high Ca/Sr. Waters moving through these various compartments will obtain Sr/Ba and Ca/Sr ratios reflecting these characteristics, and thus variations of Sr/Ba and Ca/Sr of streamwater provide evidence of the depth of water flowpaths feeding the streams. 87Sr/86Sr of exchangeable Sr spans a broad range from 0.715 to 0.725, with highest values along the mid-to upper flanks of the catchment and lowest values in a broad zone along the central axis of the catchment associated with numerous groundwater seeps. Thus, variations of 87Sr/86Sr in streamwater provide evidence of the spatial distribution of water flowpaths feeding the streams. In addition, we are exploring the use of Sr and Ba stable isotope ratios (88Sr/86Sr, 138Ba/134Ba) as novel tracers of Sr and Ba sources in catchments. Initial results indicate that both Sr and Ba stable isotopes are fractionated by plants similarly to patterns observed globally for Ca stable isotopes. We hypothesize that while biologically-cycled Ca is efficiently retained in the organic soil-plant system, biologically-cycled Sr and especially Ba will be more easily leached by soil waters and delivered to the streams and thus their stable isotope ratios may provide an additional means to distinguish between shallow and deep water flowpaths in forested catchments.

Selection of a suitable plant for phytoremediation in mining artisanal zones.

PubMed

Chamba, I; Gazquez, M J; Selvaraj, T; Calva, J; Toledo, J J; Armijos, C

2016-09-01

A study was undertaken with the aim of identifying a suitable plant for the phytoremediation of metal-polluted soil from an artisanal mining area in Ecuador. Three zones including a natural zone (NZ), abandoned zone (AZ) and intensively mined zone (IZ) were selected. Three common native plants grown in the three zones were identified and collected, including Miconia zamorensis, Axonopus compressus and Erato polymnioides. The percentage of arbuscular mycorrhizal colonization that benefits their own survival in polluted soil was analyzed in the root samples of these candidate species. Analysis of the soils and plants collected from the different zones showed that the concentrations of Pb, Zn, Cu and Cd were comparatively lower in the NZ, higher in the AZ and IZ, and highest in the AZ for all the metals. The concentration of all these metals in plant tissues was the highest in E. polymnioides. The data analysis including the metal accumulation index, bioconcentration factor and translocation factor strongly identified E. polymnioides as a hyperaccumulator plant suitable for phytoremediation.

Watershed management in the central and southern Rocky Mountains: A summary of the status of our knowledge by vegetation types

Treesearch

Charles F. Leaf

1975-01-01

Summarizes a series of comprehensive reports on watershed management in five major vegetation zones: (1) the coniferous forest subalpine zone; (2) the Front Range ponderosa pine zone; (3) the Black Hills ponderosa pine zone; (4) the alpine zone; and (5) the big sagebrush zone. Includes what is known about the hydrology of these lands, what hydrologic principles are...

[Position of Betula ermanii population ecotone in Changbai Mountains].

PubMed

Zou, Chunjing; Wang, Xiaochun; Han, Shijie

2004-12-01

The vegetation on the northern slope of Changbai Mountains forms a vertical zone due to the vertical differentiation of moisture and heat conditions. Ecotones are obviously existed between different vegetation zones, but it is difficult to decide their positions. In the area from 1400 m to 2200 m elevation, we adopted the methods of gradient sampling, fractal analysis, population pattern analysis, and interspecific competition index analysis to describe Betula ermanii population ecotone. The results showed that there was a forest ecotone between Betula ermanii and Picea-Abies forest near elevation 1650 m, and there was a forest line ecotone between Betula ermanii and alpine tundra near elevation 2080 m.

50,000 years of Environmental Change in West Tropical Africa

NASA Astrophysics Data System (ADS)

Gosling, W. D.; Miller, C. S.

2010-12-01

Tropical forests provide three vital ‘ecosystem services’ to the Earth, they: i) contain c. 40% of the terrestrial carbon stock, ii) store c. 50% of global biodiversity, and iii) feedback into global climate and carbon cycles. In addition, tropical forests are thought to have been actively absorbing atmospheric carbon dioxide over recent decades and consequently may be mitigating the impact of ongoing human induced global climate change. The services provided by tropical ecosystems are now threatened by human land use practices and projected future climate change. However, due to the complex nature of tropical ecosystems it is unclear how vegetation will respond to changes in global climate conditions. To provide an empirical insight into the response of tropical vegetation to global climate change it is necessary to learn lessons from the past by exploring the fossil record. Lake sediments are the ideal source for fossils to provide evidence of terrestrial vegetation response to past global climate change. The identification of fossil pollen grains trapped within lake sediments is a tried and tested way of establishing past terrestrial vegetation change. Determining the types of plant represented in the fossil pollen record at any particular point in time provides a good indication of the vegetation that surrounded that lake during sediment deposition. In this paper we present a new c. 50,000 year fossil pollen record from Lake Bosumtwi (Ghana; 06o 30’N, 01o 25’ W; c. 100 m above sea level). Lake Bosumtwi is today located within the Guineo-Congolian rainforest close to the ecotone. The seasonal migration of the Inter Tropical Convergence Zone (ITCZ) passes over Bosumtwi and consequently vegetation is likely to be sensitive to any changes in the ITCZ position and the associated monsoon. Sediments recovered from Lake Bosumtwi in 2004 by the Intercontinental Drilling Program provide an opportunity to investigate tropical vegetation response to climate change at a high resolution. Sub-millennial resolution fossil pollen data from Bosumtwi can be divided into three distinct pollen assemblage zones through the last 50,000 years. The oldest zone (c. 51,000-28,000 years ago) is dominated by grasses but has some lowland tropical (Moraceae/Urticaceae c. 11 %) and montane (Olea c. 8 %). woodland elements. The second zone (c. 28,000-11,700 years ago) is again dominated by grasses with few other associated elements besides obligate aquatic Cyperaceae and Typha. The youngest zone (c. 11,700 years ago to present) is the most palynologically diverse and contains tropical forest elements >50 % (including Moraceae/Urticaceae, Alchornea and Celtis). Within the youngest zone there is significant compositional change with pollen characteristic of the surface sediments only being established c.1000-2000 years ago. The three pollen zones in Lake Bosumtwi correspond directly to Marine Isotope Stages 3-1 suggesting that global temperature change was a key factor in driving change within lowland west tropical African vegetation.

Comparing Mid-Century Climate Change Projections at Convective Resolving Scales (2-km) for Life Zones Within Puerto Rico

NASA Astrophysics Data System (ADS)

Bowden, J.; Wootten, A.; Terando, A. J.; Boyles, R.; Misra, V.; Bhardwaj, A.

2016-12-01

Puerto Rico is home to over 3.5 million people and numerous endemic plant and animal species that may be at risk as a result of anthropogenic climate change. This study downscales three CMIP5 Global Circulation Models (GCMs) to a 2-km horizontal resolution using different regional climate models (RCMs) to resolve the island's climate. Here we compare projected climate change from a single GCM, CCSM4, from two RCMs centered on the mid-century, 2041-2060, for a high greenhouse gas emission scenario, RCP8.5. We will discuss similarities and differences in ecologically relevant climate variables, which were selected based on dialogue with experts who have knowledge about potential biological impacts of climate change for current life zones within Puerto Rico. Notable differences appear between the RCMs and include regions with critical ecosystems, such as the El Yunque National Forest in northeast Puerto Rico. This study helps to highlight RCMs structural uncertainty at convective resolving scales.

Darcy's law predicts widespread forest mortalityunder climate warming

NASA Astrophysics Data System (ADS)

Allen, C. D.; McDowell, N. G.

2015-12-01

Drought and heat-induced tree mortality is accelerating in many forest biomes as a consequence of a warming climate, resulting in a threat to global forests unlike any in recorded history. Forests store the majority of terrestrial carbon, thus their loss may have significant and sustained impacts on the global carbon cycle. We used a hydraulic corollary to Darcy's law, a core principle of vascular plant physiology, to predict characteristics of plants that will survive and die during drought under warmer future climates. Plants that are tall with isohydric stomatal regulation, low hydraulic conductance, and high leaf area are most likely to die from future drought stress. Thus, tall trees of old-growth forests are at the greatest risk of loss, which has ominous implications for terrestrial carbon storage. This application of Darcy's law indicates today's forests generally should be replaced by shorter and more xeric plants, owing to future warmer droughts and associated wildfires and pest attacks. The Darcy's corollary also provides a simple, robust framework for informing forest management interventions needed to promote the survival of current forests. There are assumptions and omissions in this theoretical prediction, as well as new evidence supporting its predictions, both of which I will review. Given the robustness of Darcy's law for predictions of vascular plant function, we conclude with high certainty that today's forests are going to be subject to continued increases in mortality rates that will result in substantial reorganization of their structure and carbon storage.

The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

PubMed

Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

2016-01-01

Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages.

The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants

PubMed Central

Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

2016-01-01

Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

Opportunities for making wood products from small diameter trees in Colorado

Treesearch

Dennis L. Lynch; Kurt H. Mackes

2002-01-01

Colorado's forests are at risk to forest health problems and catastrophic fire. Forest areas at high risk to catastrophic fire, commonly referred to as Red Zones, contain 2.4 million acres in the Colorado Front Range and 6.3 million acres Statewide. The increasing frequency, size, and intensity of recent forest fires have prompted large appropriations of Federal...

THE QUANTITY AND TURNOVER OF DEAD WOOD IN PERMANENT FOREST PLOTS IN SIX LIFE ZONES OF VENEZUELA

EPA Science Inventory

Dead wood can be an important component of the carbon pool in many forests, but few measurements have been made of this pool in tropical forests. To fill this gap, we determined the quantity of dead wood (downed and standing dead) in 25 long-term (up to 30 yr) permanent forest pl...

Effects of riparian buffer width on wood loading in headwater streams after repeated forest thinning

Treesearch

Julia I. Burton; Deanna H. Olson; Klaus J. Puettmann

2016-01-01

Forested riparian buffer zones are used in conjunction with upland forest management, in part, to provide for the recruitment for large wood to streams. Small headwater streams account for the majority of stream networks in many forested regions. Yet, our understanding of how riparian buffer width influences wood dynamics in headwater streams is relatively less...

Influence of forest road buffer zones on sediment transport in the Southern Appalachian Region

Treesearch

Johnny M. Grace; Stanley J. Zarnoch

2013-01-01

A gap exists in the understanding of the effectiveness of forest road best management practices (BMP) in controlling sediment movement and minimizing risks of sediment delivery to forest streams. The objective of this paper is to report the findings of investigations to assess sediment travel distances downslope of forest roads in the Appalachian region, relate...

Soil carbon in arid and semiarid forest ecosystems [Chapter 18

Treesearch

Daniel G. Neary; Steven T. Overby; Stephen C. Hart

2002-01-01

Forests of the semiarid and arid zones of the interior western United States (US) are some of the most unique in North America. They occupy 11 to 34% of the landscape at mostly higher elevations (USDA Forest Service, 1981). These forests are characterized by a high diversity of flora, fauna, climates, elevations, soils, geology, hydrology, and productivity. Within the...

Fire emissions in central Siberia

Treesearch

Douglas J. McRae; Steve P. Baker; Yuri N. Samsonov; Galina A. Ivanova

2009-01-01

Wildfires in the Russian boreal forest zone are estimated to typically burn 12-14 million hectares (ha) annually [Cahoon et al. 1994; Conard and Ivanova 1997; Conard et al. 2002; Dixon and Krankina 1993; Kasischke et al. 1999]. Boreal forests contain about 21 percent of global forest area and 28 percent of global forest carbon [Dixon et al. 1994], yet data on the...

Restoration of Degraded Soil in the Nanmangalam Reserve Forest with Native Tree Species: Effect of Indigenous Plant Growth-Promoting Bacteria

PubMed Central

Ramachandran, Andimuthu; Radhapriya, Parthasarathy

2016-01-01

Restoration of a highly degraded forest, which had lost its natural capacity for regeneration, was attempted in the Nanmangalam Reserve Forest in Eastern Ghats of India. In field experiment, 12 native tree species were planted. The restoration included inoculation with a consortium of 5 native plant growth-promoting bacteria (PGPB), with the addition of small amounts of compost and a chemical fertilizer (NPK). The experimental fields were maintained for 1080 days. The growth and biomass varied depending on the plant species. All native plants responded well to the supplementation with the native PGPB. The plants such as Pongamia pinnata, Tamarindus indica, Gmelina arborea, Wrightia tinctoria, Syzygium cumini, Albizia lebbeck, Terminalia bellirica, and Azadirachta indica performed well in the native soil. This study demonstrated, by using native trees and PGPB, a possibility to restore the degraded forest. PMID:27195310

Restoration of Degraded Soil in the Nanmangalam Reserve Forest with Native Tree Species: Effect of Indigenous Plant Growth-Promoting Bacteria.

PubMed

Ramachandran, Andimuthu; Radhapriya, Parthasarathy

Restoration of a highly degraded forest, which had lost its natural capacity for regeneration, was attempted in the Nanmangalam Reserve Forest in Eastern Ghats of India. In field experiment, 12 native tree species were planted. The restoration included inoculation with a consortium of 5 native plant growth-promoting bacteria (PGPB), with the addition of small amounts of compost and a chemical fertilizer (NPK). The experimental fields were maintained for 1080 days. The growth and biomass varied depending on the plant species. All native plants responded well to the supplementation with the native PGPB. The plants such as Pongamia pinnata, Tamarindus indica, Gmelina arborea, Wrightia tinctoria, Syzygium cumini, Albizia lebbeck, Terminalia bellirica, and Azadirachta indica performed well in the native soil. This study demonstrated, by using native trees and PGPB, a possibility to restore the degraded forest.

Invasive plants transform the three-dimensional structure of rain forests

PubMed Central

Asner, Gregory P.; Hughes, R. Flint; Vitousek, Peter M.; Knapp, David E.; Kennedy-Bowdoin, Ty; Boardman, Joseph; Martin, Roberta E.; Eastwood, Michael; Green, Robert O.

2008-01-01

Biological invasions contribute to global environmental change, but the dynamics and consequences of most invasions are difficult to assess at regional scales. We deployed an airborne remote sensing system that mapped the location and impacts of five highly invasive plant species across 221,875 ha of Hawaiian ecosystems, identifying four distinct ways that these species transform the three-dimensional (3D) structure of native rain forests. In lowland to montane forests, three invasive tree species replace native midcanopy and understory plants, whereas one understory invader excludes native species at the ground level. A fifth invasive nitrogen-fixing tree, in combination with a midcanopy alien tree, replaces native plants at all canopy levels in lowland forests. We conclude that this diverse array of alien plant species, each representing a different growth form or functional type, is changing the fundamental 3D structure of native Hawaiian rain forests. Our work also demonstrates how an airborne mapping strategy can identify and track the spread of certain invasive plant species, determine ecological consequences of their proliferation, and provide detailed geographic information to conservation and management efforts. PMID:18316720

High compatibility between arbuscular mycorrhizal fungal communities and seedlings of different land use types in a tropical dry ecosystem.

PubMed

Gavito, Mayra E; Pérez-Castillo, Daniel; González-Monterrubio, César F; Vieyra-Hernández, Teresa; Martínez-Trujillo, Miguel

2008-12-01

We conducted this study to explore limitations for the establishment of mycorrhizal associations in disturbed areas of the tropical dry ecosystem in the Chamela region of Jalisco, Mexico. Specifically, we: (1) assessed the diversity and composition of arbuscular mycorrhizal fungal (AMF) communities through spore morphospecies identification in three common land uses (primary forest, secondary forest, and pasture), (2) tested the inoculum potential of the AMF communities and the effect of water stress on the establishment of mycorrhizal associations in seedlings of various plant species, and (3) explored the importance of AMF community composition on early seedling development. Soil and root samples were taken from 15 random points in each of three plots established in two primary forests, two 26-year-old secondary forests, and two 26-year-old pastures. We expected that because of soil degradation and management, pastures would have the lowest and primary forests the highest AMF species richness. We found evidence for changes in AMF species composition due to land use and for higher morphospecies richness in primary forests than in secondary forests and pastures. We expected also that water stress limited plant and mycorrhizal development and that plants and AMF communities from secondary forests and pastures would be less affected by (better adapted to) water stress than those from the primary forest. We found that although all plant species showed biomass reductions under water stress, only some of the plant species had lower mycorrhizal development under water stress, and this was regardless of the AMF community inoculated. The third hypothesis was that plant species common to all land use types would respond similarly to all AMF communities, whereas plant species found mainly in one land use type would grow better when inoculated with the AMF community of that specific land use type. All plant species were however equally responsive to the three AMF communities inoculated, indicating that all plants established functionally compatible AMF in each community, with no preferences. The results suggest that early seedling growth and mycorrhizal development in secondary forests and pastures is not likely limited by diversity, quantity, or quality of mycorrhizal propagules but by the high temperature and water stress conditions prevailing at those sites.

Shifts in Plant Assemblages Reduce the Richness of Galling Insects Across Edge-Affected Habitats in the Atlantic Forest.

PubMed

Souza, Danielle G; Santos, Jean C; Oliveira, Marcondes A; Tabarelli, Marcelo

2016-10-01

Impacts of habitat loss and fragmentation on specialist herbivores have been rarely addressed. Here we examine the structure of plant and galling insect assemblages in a fragmented landscape of the Atlantic forest to verify a potential impoverishment of these assemblages mediated by edge effects. Saplings and galling insects were recorded once within a 0.1-ha area at habitat level, covering forest interior stands, forest edges, and small fragments. A total of 1,769 saplings from 219 tree species were recorded across all three habitats, with differences in terms of sapling abundance and species richness. Additionally, edge-affected habitats exhibited reduced richness of both host-plant and galling insects at plot and habitat spatial scale. Attack levels also differed among forest types at habitat spatial scale (21.1% of attacked stems in forest interior, 12.4% in small fragments but only 8.5% in forest edges). Plot ordination resulted in three clearly segregated clusters: one formed by forest interior, one by small fragments, and another formed by edge plots. Finally, the indicator species analysis identified seven and one indicator plant species in forest interior and edge-affected habitats, respectively. Consequently, edge effects lead to formation of distinct taxonomic groups and also an impoverished assemblage of plants and galling insects at multiple spatial scales. The results of the present study indicate that fragmentation-related changes in plant assemblages can have a cascade effects on specialist herbivores. Accordingly, hyperfragmented landscapes may not be able to retain an expressive portion of tropical biodiversity. © 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.

Resilient networks of ant-plant mutualists in Amazonian forest fragments.

PubMed

Passmore, Heather A; Bruna, Emilio M; Heredia, Sylvia M; Vasconcelos, Heraldo L

2012-01-01

The organization of networks of interacting species, such as plants and animals engaged in mutualisms, strongly influences the ecology and evolution of partner communities. Habitat fragmentation is a globally pervasive form of spatial heterogeneity that could profoundly impact the structure of mutualist networks. This is particularly true for biodiversity-rich tropical ecosystems, where the majority of plant species depend on mutualisms with animals and it is thought that changes in the structure of mutualist networks could lead to cascades of extinctions. We evaluated effects of fragmentation on mutualistic networks by calculating metrics of network structure for ant-plant networks in continuous Amazonian forests with those in forest fragments. We hypothesized that networks in fragments would have fewer species and higher connectance, but equal nestedness and resilience compared to forest networks. Only one of the nine metrics we compared differed between continuous forest and forest fragments, indicating that networks were resistant to the biotic and abiotic changes that accompany fragmentation. This is partially the result of the loss of only specialist species with one connection that were lost in forest fragments. We found that the networks of ant-plant mutualists in twenty-five year old fragments are similar to those in continuous forest, suggesting these interactions are resistant to the detrimental changes associated with habitat fragmentation, at least in landscapes that are a mosaic of fragments, regenerating forests, and pastures. However, ant-plant mutualistic networks may have several properties that may promote their persistence in fragmented landscapes. Proactive identification of key mutualist partners may be necessary to focus conservation efforts on the interactions that insure the integrity of network structure and the ecosystems services networks provide.

An assessment of autumn olive in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2016-01-01

This publication is part of a series of research notes that provide an overview of the invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by...

Forests in a water limited world under climate change

Treesearch

C. Mátyás; G. Sun

2014-01-01

The debate on ecological and climatic benefits of planted forests at the sensitive dry edge of the closed forest belt (i.e. at the ‘xeric limits’) is still unresolved. Forests sequester atmospheric carbon dioxide, accumulate biomass, control water erosion and dust storms, reduce river sedimentation, and mitigate small floods. However, planting trees in areas previously...

An assessment of nonnative bush honeysuckle in northern U.S. forests

Treesearch

Cassandra Kurtz; M.H. Hansen

2015-01-01

This publication is part of a series that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by NRS...

Medicinal and dietary supplements: specialty forest products with a long tradition

Treesearch

James L. Chamberlain; A.L. Hammett

1999-01-01

Over the last five years forest products other than timber-based products have received a great deal of attention. The markets for medicinal plants that are collected from the forests are growing rapidly. Some reports suggest this segment of the non-timber forest products industry is expanding faster than the timber-based industry. Plants used for their therapeutic...

An assessment of common buckthorn in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2018-01-01

This publication is part of a series of that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the USDA Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by...

Patterns of exotic plant invasions in Pennsylvania's Allegheny National Forest using intensive Forest Inventory and Analysis plots

Treesearch

Cynthia D. Huebner; Randall S. Morin; Ann Zurbriggen; Robert L. White

2009-01-01

Intensive Forest Inventory and Analysis (FIA) plot data collected in the Allegheny National Forest (ANF), Pennsylvania, between 1999 and 2006 were evaluated for their ability to predict ANF's vulnerability to invasion by exotic plants. A total of 26 variables classified by biotic, abiotic, or disturbance characteristics were examined. Likelihood of colonization by...

An assessment of Japanese honeysuckle in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2015-01-01

This publication is part of a series that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by NRS...

An assessment of garlic mustard in northern U.S. forests

Treesearch

Cassandra M. Kurtz; Mark H. Hansen

2014-01-01

This publication is part of a series that provides an overview of the presence of invasive plant species monitored on an extensive systematic network of plots measured by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station (NRS). Each research note features one of the invasive plants monitored on forested plots by FIA...

Plant and soil nutrients in young versus mature central Appalachian hardwood stands

Treesearch

Frank S. Gilliam; Mary Beth Adams

1995-01-01

Most models of forest succession and forest recovery following disturbance predict changes in nutrient availability. The purpose of this study was to compare soil and herbaceous layer plant nutrients between two young (~20 yr) and two mature (~80 yr) forest stands on Fernow Experimental Forest, Parsons, West Virginia. All sampling was carried out within 15 circular 0....

The last millennia history of detrital sedimentation in the Lower Seine Valley geosystem (Normandy, NW France)

NASA Astrophysics Data System (ADS)

Sechi-Sapowicz, S.; Sebag, D.; Laignel, B.; Lepert, T.

2012-04-01

Actually, the respective role of climate and Man in the Holocene environmental changes is still debated. It is obvious that those factors are together implicated in changes in hydrological balance, soil erosion and terrigenous sedimentation. Indeed regional synthesis showed the increasing human pressure in combination to climatic variability since the Neolithic time. Thus, in Northwest Europe, increasing land use is well documented as forest clearance or alternation of deforestation and farming periods and of forest recovery episodes. In this aim, the lower valleys were particularly sensitive to changes in recent mutation and provide valuable Holocene archives to track changes in sedimentary dynamics. In this way an accentuated fine alluviation is often associated with land human activities linked to erosive processes during climatic oscillation in Northwest European valleys. In the West Paris Basin, in Normandy, France, several studies emphasized a single forcing on the Quaternary and Holocene evolution: climate changes or sea level rise or human activities in the Lower Seine Valley (LSV). Research on Holocene sequences, field, palaeoenvironnemental data and archaeological investigations from the Lower Seine Valley and tributaries result in a global vision of the erosional processes at the origin of detrital inputs and terrigenous records. Reading on those records we define three main sectors of the Lower Seine Valley: Estuarine zone, Fluvial zone and Tributaries. We define seven erosional/detrital phases directly or indirectly triggered by the increase anthropogenic pressure combined, or not, to climate change. Those phases are the key periods of changes on major terrigenous sedimentation events. During the Early Holocene climate pejoration, a deep and linear under-scour of plateaus and changes in drainage network load to the "Mesolithic detritism". Those sediments with proximal origins, were firstly recorded in the estuarine zone and after in the fluvial zone. During the Mid-Holocene transition the deglaciation load to the increase in hydrologic fluxes. Only the estuarine zone was interested by sea level change and the fluvial zone and tributaries show a relative environmental and slope stability (biostatyc conditions) related to forest plant cover. Only a peatland and autochthonous sedimentation characterize the fluvial zone affected by regional phreatic-level rise. This biostatyc period was break off when the Late Holocene erosional processes pickup. Those processes lead to a radical change in sedimentation witch switch over from proximal to distal origins. The consequent detritism was firstly recorded in TSR with the grey clay, then in the whole fluvial environments with organic silts and after in the estuarine zone with laminated sand with silt. Forest clearance and agricultural development were the main responsible factors of this induced detritism documented in the whole Paris Basin and in Northwest Europe. The transition from forested to open environment play in favour to a pickup of runoff processes and the organic accumulation in peatland was progressively substituted by terrigenous detrital supplies in marsh and swamps. The Bronze Age metallurgy development and tillage practices induced this detritism in the whole environments. From the end of the Bronze Age and the Iron Age a drastic increase in the anthropogenic pressure on the regional sedimentary dynamics was the main responsible for the detritism recorded in the fluvial zone (quartzy silt) marking the end of the organic sedimentation in this part of the LSV. During this time grey clay carried on depositing in tributaries. During the Middle Age a generalised detritism was recorded in the whole region. Finally, XIII-XIV-XVth centuries corresponds to the agricultural revolution and the plough employ generally introduced in the whole region. All informations collected about erosional forcings factors and sedimentary responses in the region, lead to lay at the anthropogenic pressure the main role since the Neolithic time. The human pressure is the first cause of the regional detritism start out. The LSV experienced a pattern of soil erosional processes similar to that of numerous valleys in northwestern Europe. A multiplication of sites and more accurate analyses in the tributaries are needed in order to have a better global view of the detrital-erosional phases and the associated terrigenous fluxes. Future research will focus on tributaries sites which are not study until now.

Mapping potential carbon and timber losses from hurricanes using a decision tree and ecosystem services driver model.

PubMed

Delphin, S; Escobedo, F J; Abd-Elrahman, A; Cropper, W

2013-11-15

Information on the effect of direct drivers such as hurricanes on ecosystem services is relevant to landowners and policy makers due to predicted effects from climate change. We identified forest damage risk zones due to hurricanes and estimated the potential loss of 2 key ecosystem services: aboveground carbon storage and timber volume. Using land cover, plot-level forest inventory data, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, and a decision tree-based framework; we determined potential damage to subtropical forests from hurricanes in the Lower Suwannee River (LS) and Pensacola Bay (PB) watersheds in Florida, US. We used biophysical factors identified in previous studies as being influential in forest damage in our decision tree and hurricane wind risk maps. Results show that 31% and 0.5% of the total aboveground carbon storage in the LS and PB, respectively was located in high forest damage risk (HR) zones. Overall 15% and 0.7% of the total timber net volume in the LS and PB, respectively, was in HR zones. This model can also be used for identifying timber salvage areas, developing ecosystem service provision and management scenarios, and assessing the effect of other drivers on ecosystem services and goods. Copyright © 2013 Elsevier Ltd. All rights reserved.

Seedling growth and biomass allocation in relation to leaf habit and shade tolerance among 10 temperate tree species.

PubMed

Modrzyński, Jerzy; Chmura, Daniel J; Tjoelker, Mark G

2015-08-01

Initial growth of germinated seeds is an important life history stage, critical for establishment and succession in forests. Important questions remain regarding the differences among species in early growth potential arising from shade tolerance. In addition, the role of leaf habit in shaping relationships underlying shade tolerance-related differences in seedling growth remains unresolved. In this study we examined variation in morphological and physiological traits among seedlings of 10 forest tree species of the European temperate zone varying in shade tolerance and leaf habit (broadleaved winter-deciduous species vs needle-leaved conifers) during a 10-week period. Seeds were germinated and grown in a controlled environment simulating an intermediate forest understory light environment to resolve species differences in initial growth and biomass allocation. In the high-resource experimental conditions during the study, seedlings increased biomass allocation to roots at the cost of leaf biomass independent of shade tolerance and leaf habit. Strong correlations between relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA) and leaf mass fraction (LMF) indicate that physiology and biomass allocation were equally important determinants of RGR as plant structure and leaf morphology among these species. Our findings highlight the importance of seed mass- and seed size-related root morphology (specific root length-SRL) for shade tolerance during early ontogeny. Leaf and plant morphology (SLA, LAR) were more successful in explaining variation among species due to leaf habit than shade tolerance. In both broadleaves and conifers, shade-tolerant species had lower SRL and greater allocation of biomass to stems (stem mass fraction). Light-seeded shade-intolerant species with greater SRL had greater RGR in both leaf habit groups. However, the greatest plant mass was accumulated in the group of heavy-seeded shade-tolerant broadleaves. The results of our study suggest that the combinations of plant attributes enhancing growth under high light vary with shade tolerance, but differ between leaf habit groups. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Plants of the Bayshore.

ERIC Educational Resources Information Center

Bachle, Leo; And Others

This field guide gives pictures and descriptions of plants that can be found along the San Francisco Bayshore, especially along the Hayward shoreline. The plants are divided into three categories, those of the mud-flat zone, the drier zone, and the levee zone. Eighteen plants are represented in all. The guide is designed to be used alone, with an…

Analyzing riparian forest cover changes along the Firniz River in the Mediterranean City of Kahramanmaras in Turkey.

PubMed

Akay, Abdullah E; Sivrikaya, Fatih; Gulci, Sercan

2014-05-01

Riparian forests adjacent to surface water are important transitional zones which maintain and enrich biodiversity and ensure the sustainability in a forest ecosystem. Also, riparian forests maintain water quality, reduce sediment delivery, enhance habitat areas for aquatic life and wildlife, and provide ecological corridors between the upland and the downstream. However, the riparian ecosystems have been degraded mainly due to human development, forest operations, and agricultural activities. In order to evaluate the impacts of these factors on riparian forests, it is necessary to estimate trends in forest cover changes. This study aims to analyze riparian forest cover changes along the Firniz River located in Mediterranean city of Kahramanmaras in Turkey. Changes in riparian forest cover from 1989 to 2010 have been determined by implementing supervised classification method on a series of Landsat TM imagery of the study area. The results indicated that the classification process applied on 1989 and 2010 images provided overall accuracy of 80.08 and 75 %, respectively. It was found that the most common land use class within the riparian zone was productive forest, followed by degraded forest, agricultural areas, and other land use classes. The results also indicated that the areas of degraded forest and forest openings increased, while productive forest and agricultural areas decreased between the years of 1989 and 2010. The amount of agricultural areas decreased due to the reduction in the population of rural people. According to these results, it can be concluded that special forest management and operation techniques should be implemented to restore the forest ecosystem in riparian areas.

EMERGY SYNTHESIS OF AN AGRO-FOREST RESTORATION SYSTEM IN LOWER SUBTROPICAL CHINA

EPA Science Inventory

The low subtropical zone is the most populated and seriously degraded area in China; therefore, highly efficient restoration of degraded lands is the key to sustainable development of this region. An agro-forest restoration mode consisting of an Acacia mangium forest, a Citrus re...

Introduction: Forest restoration in temperate and boreal zones

Treesearch

Emile Gardiner; Katrine Hahn; Magnus Löf

2003-01-01

The past decade has witnessed an acceleration of forest restoration activities around the globe. Afforestation of former agricultural land, rehabilitation of natural forest processes and structures at the stand and landscape levels, and conversion of single-species plantations to mixed-species stands are among the prominent types of restoration practices currently...

Traditional use of medicinal plants in the boreal forest of Canada: review and perspectives

PubMed Central

2012-01-01

Background The boreal forest of Canada is home to several hundred thousands Aboriginal people who have been using medicinal plants in traditional health care systems for thousands of years. This knowledge, transmitted by oral tradition from generation to generation, has been eroding in recent decades due to rapid cultural change. Until now, published reviews about traditional uses of medicinal plants in boreal Canada have focused either on particular Aboriginal groups or on restricted regions. Here, we present a review of traditional uses of medicinal plants by the Aboriginal people of the entire Canadian boreal forest in order to provide comprehensive documentation, identify research gaps, and suggest perspectives for future research. Methods A review of the literature published in scientific journals, books, theses and reports. Results A total of 546 medicinal plant taxa used by the Aboriginal people of the Canadian boreal forest were reported in the reviewed literature. These plants were used to treat 28 disease and disorder categories, with the highest number of species being used for gastro-intestinal disorders, followed by musculoskeletal disorders. Herbs were the primary source of medicinal plants, followed by shrubs. The medicinal knowledge of Aboriginal peoples of the western Canadian boreal forest has been given considerably less attention by researchers. Canada is lacking comprehensive policy on harvesting, conservation and use of medicinal plants. This could be explained by the illusion of an infinite boreal forest, or by the fact that many boreal medicinal plant species are widely distributed. Conclusion To our knowledge, this review is the most comprehensive to date to reveal the rich traditional medicinal knowledge of Aboriginal peoples of the Canadian boreal forest. Future ethnobotanical research endeavours should focus on documenting the knowledge held by Aboriginal groups that have so far received less attention, particularly those of the western boreal forest. In addition, several critical issues need to be addressed regarding the legal, ethical and cultural aspects of the conservation of medicinal plant species and the protection of the associated traditional knowledge. PMID:22289509

Planting and care of fine hardwood seedlings: Planting hardwood seedlings in the Central Hardwood Region.

Treesearch

Paula M. Pijut

2003-01-01

Forest tree planting in the United States on public and private land exceeded 2.6 million acres in 1999. Of that total, approximately 1.3 million acres (48 percent) were planted by private individuals (AF & PA 2001). In the Central Hardwood Region forest tree planting by private landowners exceeded 100,000 acres in 1999. Trees are planted for various reasons...

Oleoresin, Chemistry and Spectral Reflectance in "Stressed" Lodgepole and White Bark Pine, Mammoth Mountain, California

NASA Technical Reports Server (NTRS)

Hickey, James C.; Birnie, Richard W.; Zhao, Mei-Xun

2001-01-01

Development of methods to identify the physical and chemical character of materials on the earth's surface is one of the foci of hyperspectral remote sensing activities. Enhancing the ability to elucidate changes in foliar chemistry that relate to the health of a plant is a benefit to plant physiologists, foresters, and plant ecologists, as well as geologist and environmental scientists. Vegetation covers the landscape throughout the temperate and tropical regions of the earth. The existence of vegetation in these areas presents special problems to remote sensing systems since geologic bedrock and alteration zones are masked. At times, however, alterations in the soil/sediment geochemical environment result in foliar chemical changes that are detectable via remote sensing. Examples include monitoring of chlorophyll reflectance/fluorescence and equivalent water thickness indices as indicators of drought-induced plant stress. Another processing and interpretation approach used with hyperspectral data has been principal components analysis (PCA). Rowan et al. used PCA to identify absorption feature patterns obtained from vegetated areas with discrete bedrock geology or mineralization as the substrate. Many researchers highlight the need to advance our ability for hyperspectral imaging in vegetated areas as a near-term priority.

Forestry 101.

ERIC Educational Resources Information Center

Markham, Mary T.

2000-01-01

Introduces a unit on forest management in which students manage the school forest. Involves students in tree identification, determining the size or volume and height of trees, and evaluation of the forest for management decisions. Integrates mathematics, writing, and social studies with plant classification, plant reproduction, and the use of…

Production and standing crop of litter and humus in a forest exposed to chronic gamma irradiation for twelve years

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

Armentano, T.V.; Woodwell, G.M.

Continuous exposure since 1961 of an oak-pine forest at Brookhaven National Laboratory to chronic gamma irradiation has shown: (1) progressive reduction in litter production from the first year through 1965; (2) greater litter production in 1973 compared to 1965 at exposure rates below 9 R/day primarily because of the prolific sprouting of the oaks, especially Quercus alba; (3) further reduction in litter production in intermediate zones (14-49 R/day) from 1965 to 1973 as a result of replacement of the forest by a Carex pensylvanica mat; (4) increased litter production in the high exposure zone (125 R/day) in 1973 as amore » result of colonization by adventive species; (5) reduction in the standing crop of litter by 1973 at the lowest exposure rate studied (3.5 R/day) although in 1965 there was no reduction at exposure rates up to 15 R/day; (6) decline in humus content at 4.6 R/day and above with the standing crop in the Carex zone exceeding that of the shrub and damaged forest zones of lower exposures. Both further losses and partial recovery in the production and storage of organic matter have occurred since 1965. These changes constitute a portion of the long-term response of the forest to chronic disturbance. The pattern of response is the result of ecosystem processes that are still not in equilibrium with the chronic disturbance and which were not predictable from short-term studies, even those spanning as much as 4 yr.« less

An interdisciplinary, outcome-based approach to astmospheric CO2 mitigation with planted southern pine forests

NASA Astrophysics Data System (ADS)

Martin, T.; Fox, T.; Peter, G.; Monroe, M.

2012-12-01

The Pine Integrated Network: Education, Mitigation and Adaptation Project ("PINEMAP") was funded by National Institute of Food and Agriculture to produce outcomes of enhanced climate change mitigation and adaptation in planted southern pine ecosystems. The PINEMAP project leverages a strong group of existing networks to produce synergy and cooperation on applied forestry research in the region. Over the last 50 years, cooperative research on planted southern pine management among southeastern U.S. universities, government agencies, and corporate forest landowners has developed and facilitated the widespread implementation of improved genetic and silvicultural technology. The impact of these regional research cooperatives is difficult to overstate, with current members managing 55% of the privately owned planted pine forestland, and producing 95% of the pine seedlings planted each year. The PINEMAP team includes the eight major forestry cooperative research programs, scientists from eleven land grant institutions, the US Forest Service, and climate modeling and adaptation specialists associated with the multi-state SE Climate Consortium and state climate offices. Our goal is to create and disseminate the knowledge that enables landowners to: harness planted pine forest productivity to mitigate atmospheric CO2; more efficiently use nitrogen and other fertilizer inputs; and adapt their forest management to increase resilience in the face of changing climate. We integrate our team's infrastructure and expertise to: 1) develop breeding, genetic deployment and innovative management systems to increase C sequestration and resilience to changing climate of planted southern pine forests ; 2) understand interactive effects of policy, biology, and climate change on sustainable management; 3) transfer new management and genetic technologies to private industrial and non-industrial landowners; and 4) educate a diverse cross-section of the public about the relevance of forests, forest management, and climate change. These efforts will enable our stakeholders to enhance the productivity of southern pine forests, while maintaining social, economic, and ecological sustainability.

Salamander abundance along road edges and within abandoned logging roads in Appalachian forests.

PubMed

Semlitsch, Raymond D; Ryan, Travis J; Hamed, Kevin; Chatfield, Matt; Drehman, Bethany; Pekarek, Nicole; Spath, Mike; Watland, Angie

2007-02-01

Roads may be one of the most common disturbances in otherwise continuous forested habitat in the southern Appalachian Mountains. Despite their obvious presence on the landscape, there is limited data on the ecological effects along a road edge or the size of the "road-effect zone." We sampled salamanders at current and abandoned road sites within the Nantahala National Forest, North Carolina (U.S.A.) to determine the road-effect zone for an assemblage of woodland salamanders. Salamander abundance near the road was reduced significantly, and salamanders along the edges were predominantly large individuals. These results indicate that the road-effect zone for these salamanders extended 35 m on either side of the relatively narrow, low-use forest roads along which we sampled. Furthermore, salamander abundance was significantly lower on old, abandoned logging roads compared with the adjacent upslope sites. These results indicate that forest roads and abandoned logging roads have negative effects on forest-dependent species such as plethodontid salamanders. Our results may apply to other protected forests in the southern Appalachians and may exemplify a problem created by current and past land use activities in all forested regions, especially those related to road building for natural-resource extraction. Our results show that the effect of roads reached well beyond their boundary and that abandonment or the decommissioning of roads did not reverse detrimental ecological effects; rather, our results indicate that management decisions have significant repercussions for generations to come. Furthermore, the quantity of suitable forested habitat in the protected areas we studied was significantly reduced: between 28.6% and 36.9% of the area was affected by roads. Management and policy decisions must use current and historical data on land use to understand cumulative impacts on forest-dependent species and to fully protect biodiversity on national lands.

Using GIS to integrate FIA and remotely sensed data to estimate the invasibility of major forest types by non-native invasive plants in the Upper Midwest, USA

Treesearch

Zhaofei Fan; W. Keith Moser; Michael K. Crosby; Weiming Yu

2012-01-01

Non-native invasive plants (NNIP) are rapidly spreading into natural ecosystems such as forests in the Upper Midwest. Using the strategic inventory data from the 2005-2006 U.S. Department of Agriculture, Forest Service’s Forest Inventory and Analysis (FIA) program and forest land cover data, we estimated the regional-invasibility patterns of NNIPs for major...

Deceleration efficiencies of shrub windbreaks in a wind tunnel

NASA Astrophysics Data System (ADS)

Wu, Xiaoxu; Zou, Xueyong; Zhou, Na; Zhang, Chunlai; Shi, Sha

2015-03-01

Artemisia and Salix are dominant shrub species for windbreaks in arid areas of China, and they show similar features to shrubs in other arid areas of the world. We compared the mean velocity fields and shelter effects of two shrub windbreaks with different layouts. For a single plant of Artemisia, the higher the free airflow velocity is, the more the wind velocity around two sides of the plant increases. The velocity gradient around a single plant of Salix is smaller than that around an Artemisia plant due to the difference in the plant shapes. Seven new velocity zones in the horizontal direction appear when airflow passes through an Artemisia windbreak, including four deceleration zones and three acceleration zones. The mean velocity field that is affected by a Salix windbreak can be divided into a deceleration zone in the front, an acceleration zone above, a vortex zone behind and a restoration zone downwind of the vortex zone. Shelter effects of the shrub windbreaks vary with the wind velocity and are influenced by the construct of the windbreaks. Shrub windbreaks that have a complex construction have better shelter effects than simple ones. The shelter effects of plant windbreaks are also influenced by the growth features of the plants. Considering the plant characteristics and the shelter effects of Salix and Artemisia windbreaks, it is optimal to plant these two windbreaks together in a sand-control system. This research is intended to be useful for sand movement control in arid areas.

Fungal community composition in neotropical rain forests: the influence of tree diversity and precipitation.

PubMed

McGuire, Krista L; Fierer, Noah; Bateman, Carling; Treseder, Kathleen K; Turner, Benjamin L

2012-05-01

Plant diversity is considered one factor structuring soil fungal communities because the diversity of compounds in leaf litter might determine the extent of resource heterogeneity for decomposer communities. Lowland tropical rain forests have the highest plant diversity per area of any biome. Since fungi are responsible for much of the decomposition occurring in forest soils, understanding the factors that structure fungi in tropical forests may provide valuable insight for predicting changes in global carbon and nitrogen fluxes. To test the role of plant diversity in shaping fungal community structure and function, soil (0-20 cm) and leaf litter (O horizons) were collected from six established 1-ha forest census plots across a natural plant diversity gradient on the Isthmus of Panama. We used 454 pyrosequencing and phospholipid fatty acid analysis to evaluate correlations between microbial community composition, precipitation, soil nutrients, and plant richness. In soil, the number of fungal taxa increased significantly with increasing mean annual precipitation, but not with plant richness. There were no correlations between fungal communities in leaf litter and plant diversity or precipitation, and fungal communities were found to be compositionally distinct between soil and leaf litter. To directly test for effects of plant species richness on fungal diversity and function, we experimentally re-created litter diversity gradients in litter bags with 1, 25, and 50 species of litter. After 6 months, we found a significant effect of litter diversity on decomposition rate between one and 25 species of leaf litter. However, fungal richness did not track plant species richness. Although studies in a broader range of sites is required, these results suggest that precipitation may be a more important factor than plant diversity or soil nutrient status in structuring tropical forest soil fungal communities.

Stable carbon, oxygen, and nitrogen, isotope analysis of plants from a South Asian tropical forest: Implications for primatology.

PubMed

Roberts, Patrick; Blumenthal, Scott A; Dittus, Wolfgang; Wedage, Oshan; Lee-Thorp, Julia A

2017-06-01

Stable isotope analysis of primate tissues in tropical forest contexts is an increasingly popular means of obtaining information about niche distinctions among sympatric species, including preferences in feeding height, forest canopy density, plant parts, and trophism. However, issues of equifinality mean that feeding height, canopy density, as well as the plant parts and plant species consumed, may produce similar or confounding effects. With a few exceptions, researchers have so far relied largely on general principles and/or limited plant data from the study area as references for deducing the predominant drivers of primate isotope variation. Here, we explore variation in the stable carbon (δ 13 C), nitrogen (δ 15 N), and oxygen (δ 18 O) isotope ratios of 288 plant samples identified as important to the three primate species from the Polonnaruwa Nature Sanctuary, Sri Lanka, relative to plant part, season, and canopy height. Our results show that plant part and height have the greatest effect on the δ 13 C and δ 18 O measurements of plants of immediate relevance to the primates, Macaca sinica, Semnopithecus priam thersites, and Trachypithecus vetulus, living in this monsoonal tropical forest. We find no influence of plant part, height or season on the δ 15 N of measured plants. While the plant part effect is particularly pronounced in δ 13 C between fruits and leaves, differential feeding height, and plant taxonomy influence plant δ 13 C and δ 18 O differences in addition to plant organ. Given that species composition in different regions and forest types will differ, the results urge caution in extrapolating general isotopic trends without substantial local baselines studies. © 2017 Wiley Periodicals, Inc.

Conservation value of remnant riparian forest corridors of varying quality for amazonian birds and mammals.

PubMed

Lees, Alexander C; Peres, Carlos A

2008-04-01

Forest corridors are often considered the main instrument with which to offset the effects of habitat loss and fragmentation. Brazilian forestry legislation requires that all riparian zones on private landholdings be maintained as permanent reserves and sets fixed minimum widths of riparian forest buffers to be retained alongside rivers and perennial streams. We investigated the effects of corridor width and degradation status of 37 riparian forest sites (including 24 corridors connected to large source-forest patches, 8 unconnected forest corridors, and 5 control riparian zones embedded within continuous forest patches) on bird and mammal species richness in a hyper-fragmented forest landscape surrounding Alta Floresta, Mato Grosso, Brazil. We used point-count and track-sampling methodology, coupled with an intensive forest-quality assessment that combined satellite imagery and ground truthed data. Vertebrate use of corridors was highly species-specific, but broad trends emerged depending on species life histories and their sensitivity to disturbance. Narrow and/or highly disturbed riparian corridors retained only a depauperate vertebrate assemblage that was typical of deforested habitats, whereas wide, well-preserved corridors retained a nearly complete species assemblage. Restriction of livestock movement along riparian buffers and their exclusion from key areas alongside deforested streams would permit corridor regeneration and facilitate restoration of connectivity.

New evidence for hybrid zones of forest and savanna elephants in Central and West Africa.

PubMed

Mondol, Samrat; Moltke, Ida; Hart, John; Keigwin, Michael; Brown, Lisa; Stephens, Matthew; Wasser, Samuel K

2015-12-01

The African elephant consists of forest and savanna subspecies. Both subspecies are highly endangered due to severe poaching and habitat loss, and knowledge of their population structure is vital to their conservation. Previous studies have demonstrated marked genetic and morphological differences between forest and savanna elephants, and despite extensive sampling, genetic evidence of hybridization between them has been restricted largely to a few hybrids in the Garamba region of northeastern Democratic Republic of Congo (DRC). Here, we present new genetic data on hybridization from previously unsampled areas of Africa. Novel statistical methods applied to these data identify 46 hybrid samples--many more than have been previously identified--only two of which are from the Garamba region. The remaining 44 are from three other geographically distinct locations: a major hybrid zone along the border of the DRC and Uganda, a second potential hybrid zone in Central African Republic and a smaller fraction of hybrids in the Pendjari-Arli complex of West Africa. Most of the hybrids show evidence of interbreeding over more than one generation, demonstrating that hybrids are fertile. Mitochondrial and Y chromosome data demonstrate that the hybridization is bidirectional, involving males and females from both subspecies. We hypothesize that the hybrid zones may have been facilitated by poaching and habitat modification. The localized geography and rarity of hybrid zones, their possible facilitation from human pressures, and the high divergence and genetic distinctness of forest and savanna elephants throughout their ranges, are consistent with calls for separate species classification. © 2015 John Wiley & Sons Ltd.

Prediction of plant vulnerability to salinity increase in a coastal ecosystem by stable isotopic composition (δ18O) of plant stem water: a model study

USGS Publications Warehouse

Zhai, Lu; Jiang, Jiang; DeAngelis, Donald L.; Sternberg, Leonel d.S.L

2016-01-01

Sea level rise and the subsequent intrusion of saline seawater can result in an increase in soil salinity, and potentially cause coastal salinity-intolerant vegetation (for example, hardwood hammocks or pines) to be replaced by salinity-tolerant vegetation (for example, mangroves or salt marshes). Although the vegetation shifts can be easily monitored by satellite imagery, it is hard to predict a particular area or even a particular tree that is vulnerable to such a shift. To find an appropriate indicator for the potential vegetation shift, we incorporated stable isotope 18O abundance as a tracer in various hydrologic components (for example, vadose zone, water table) in a previously published model describing ecosystem shifts between hammock and mangrove communities in southern Florida. Our simulations showed that (1) there was a linear relationship between salinity and the δ18O value in the water table, whereas this relationship was curvilinear in the vadose zone; (2) hammock trees with higher probability of being replaced by mangroves had higher δ18O values of plant stem water, and this difference could be detected 2 years before the trees reached a tipping point, beyond which future replacement became certain; and (3) individuals that were eventually replaced by mangroves from the hammock tree population with a 50% replacement probability had higher stem water δ18O values 3 years before their replacement became certain compared to those from the same population which were not replaced. Overall, these simulation results suggest that it is promising to track the yearly δ18O values of plant stem water in hammock forests to predict impending salinity stress and mortality.

Fernbank Science Center Forest Teacher's Guide-1967.

ERIC Educational Resources Information Center

Cherry, Jim; And Others

This guide is designed primarily to familiarize teachers with the types of programs available through the Fernback Science Center. Instructional programs involving the use of the Fernbank Forest are outlined. Programs for secondary students include Plant Taxonomy, Field Ecology, Winter Taxonomy of Plants, and Climax Forest Succession. Elementary…

The Conservation of Sensitive Plants on Private Redwood Timberlands in Northern California

Treesearch

Clare Golec; Tony LaBanca; Gordon Leppig

2007-01-01

Redwood forests are not traditionally known for a diverse vascular plant flora or a large number of sensitive plant taxa. Approximately 90 percent of redwood forests are privately owned and most are managed for timber production. Historically, information on sensitive plants in the redwoods has been scarce because few sensitive plant surveys were conducted on public...

Herbaceous-layer and overstory species in clear-cut and mature central Appalachian hardwood forests

Treesearch

Frank S. Gilliam; Nicole L. Turrill; Mary Beth Adams

1995-01-01

The current interest among resource managers in ecosystem management necessitates a better understanding of the response of plant species diversity to forest management practices. This study attempted to assess the effects of one forest management practice—clear-cutting—on plant biodiversity in a mid-Appalachian hardwood forest by comparing species composition and...

Changes in plant species composition along an elevation gradient in an old-growth bottomland hardwood-Pinus taeda forest in southern Arkansas

Treesearch

Adrian G. Grell; Michael G. Shelton; Eric Heitzman

2005-01-01

Old-growth bottomland hardwood-Pinus taeda L. forests are rare in Arkansas, and the complex relationships between plant communities and environmental conditions have not been well described in these forests. To investigate these relationships, a digital elevation model was developed for a 16.2 ha old-growth bottomland hardwood-Pinus taeda forest in...

When the forest dies: the response of forest soil fungi to a bark beetle-induced tree dieback

PubMed Central

Štursová, Martina; Šnajdr, Jaroslav; Cajthaml, Tomáš; Bárta, Jiří; Šantrůčková, Hana; Baldrian, Petr

2014-01-01

Coniferous forests cover extensive areas of the boreal and temperate zones. Owing to their primary production and C storage, they have an important role in the global carbon balance. Forest disturbances such as forest fires, windthrows or insect pest outbreaks have a substantial effect on the functioning of these ecosystems. Recent decades have seen an increase in the areas affected by disturbances in both North America and Europe, with indications that this increase is due to both local human activity and global climate change. Here we examine the structural and functional response of the litter and soil microbial community in a Picea abies forest to tree dieback following an invasion of the bark beetle Ips typographus, with a specific focus on the fungal community. The insect-induced disturbance rapidly and profoundly changed vegetation and nutrient availability by killing spruce trees so that the readily available root exudates were replaced by more recalcitrant, polymeric plant biomass components. Owing to the dramatic decrease in photosynthesis, the rate of decomposition processes in the ecosystem decreased as soon as the one-time litter input had been processed. The fungal community showed profound changes, including a decrease in biomass (2.5-fold in the litter and 12-fold in the soil) together with the disappearance of fungi symbiotic with tree roots and a relative increase in saprotrophic taxa. Within the latter group, successive changes reflected the changing availability of needle litter and woody debris. Bacterial biomass appeared to be either unaffected or increased after the disturbance, resulting in a substantial increase in the bacterial/fungal biomass ratio. PMID:24671082

Passive restoration following ungulate removal in a highly disturbed tropical wet forest devoid of native seed dispersers

USGS Publications Warehouse

Nafus, Melia; Savidge, Julie A.; Yackel Adams, Amy A.; Christy, Michelle T.; Reed, Robert

2018-01-01

Overabundant ungulate populations can alter forests. Concurrently, global declines of seed dispersers may threaten native forest structure and function. On an island largely devoid of native vertebrate seed dispersers, we monitored forest succession for 7 years following ungulate exclusion from a 5-ha area and adjacent plots with ungulates still present. We observed succession from open scrub to forest and understory cover by non-native plants declined. Two trees, native Hibiscus tiliaceus and non-native Leucaena leucocephala, accounted for most forest regeneration, with the latter dominant. Neither species is dependent on animal dispersers nor was there strong evidence that plants dependent on dispersers migrated into the 5-ha study area. Passive restoration following ungulate removal may facilitate restoration, but did not show promise for fully restoring native forest on Guam. Restoration of native forest plants in bird depopulated areas will likely require active outplanting of native seedlings, control of factors resulting in bird loss, and reintroduction of seed dispersers.

A review of impacts by invasive exotic plants on forest ecosystem services

Treesearch

Kevin Devine; Songlin Fei

2011-01-01

Many of our forest ecosystems are at risk due to the invasion of exotic invasive plant species. Invasive plant species pose numerous threats to ecosystems by decreasing biodiversity, deteriorating ecosystem processes, and degrading ecosystem services. Literature on Kentucky's most invasive exotic plant species was examined to understand their potential impacts on...

36 CFR 219.9 - Diversity of plant and animal communities.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Diversity of plant and animal... PLANNING National Forest System Land Management Planning § 219.9 Diversity of plant and animal communities... diversity of plant and animal communities and the persistence of native species in the plan area. Compliance...

36 CFR 219.9 - Diversity of plant and animal communities.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Diversity of plant and animal... PLANNING National Forest System Land Management Planning § 219.9 Diversity of plant and animal communities... diversity of plant and animal communities and the persistence of native species in the plan area. Compliance...

36 CFR 219.9 - Diversity of plant and animal communities.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Diversity of plant and animal... PLANNING National Forest System Land Management Planning § 219.9 Diversity of plant and animal communities... diversity of plant and animal communities and the persistence of native species in the plan area. Compliance...

[Regenerative morphological traits in a woody species community in Tumbesian tropical dry forest].

PubMed

Romero-Saritama, José Miguel; Pérez-Rúuz, César

2016-06-01

The study of functional morphological traits enables us to know fundamental aspects of the dynamics of plant communities in local and global habitats. Regenerative morphological traits play an important role in defining plant history and ecological behavior. Seed and fruit characteristics determine to a large extent the patterns for dispersal, germination, establishment and seedling recruitment a given species exhibits on its natural habitat. Despite their prominent role, seed and fruit traits have been poorly studied at the community level of woody plant species in neo-tropical dry forests. In the present study we aimed at i) evaluate the functional role of morphological traits of seeds, fruits and embryo in woody plant species; ii) determine which are the morphological patterns present in seeds collected from the community of woody species that occur in neo-tropical dry forests; and iii) compare woody plant species seed mass values comparatively between neo-tropical dry and tropical forests. To do so, mature seeds were collected from 79 plant species that occur in the Tumbesian forest of Southwest Ecuador. The studied species included the 42 and 37 most representative tree and shrubbery species of the Tumbesian forest respectively. A total of 18 morphological traits (seven quantitative and 11 qualitative) were measured and evaluated in the seeds, fruits and embryos of the selected species, and we compared the seeds mass with other forest types. Our results showed a huge heterogeneity among traits values in the studied species. Seed mass, volume and number were the traits that vary the most at the community level, i.e. seed length ranged from 1.3 to 39 mm, and seed width from 0.6 to 25 mm. Only six embryo types were found among the 79 plant species. In 40 % of the cases, fully developed inverted embryos with large and thick cotyledons to store considerable amount of nutrients were recorded. We concluded that highly variable and functionally complementary morphological traits occur among the studied woody plants of the Tumbesian dry forest. The latter favors a plethora of behavioral mechanisms to coexist among woody species of the dry forest in response to the environmental stress that is typical of arid areas.

Forest cover type, habitat diversity, and anthropogenic influences on forest ecosystems adjoining the Maasai Mara National Reserve, Kenya

Treesearch

James Legilisho-Kiyiapi

2000-01-01

Through combined use of satellite imagery, aerial photographs, and ground truthing, a multilevel assessment was conducted in a forest block that forms a unique dispersal zone to the Maasai Mara National Reserve ecosystem. Results of the survey revealed considerable ecological diversity on an area-scale basis - in terms of ecotypes. Forest types ranged from Afro-montane...

Summer evapotranspiration trends as related to time after logging of forests in Sierra Nevada

Treesearch

Robert R. Ziemer

1964-01-01

Abstract - The quantity of summer soil moisture lost from logged forest openings was related to the length of time since the creation of the opening, in the subalpine forest zone of the Sierra Nevada west side, near the Central Sierra Snow Laboratory, California, at an elevation of 6000 to 7000 feet. Soil moisture depletion was measured in forest openings which were...

Plant hydraulic diversity buffers forest ecosystem responses to drought

NASA Astrophysics Data System (ADS)

Anderegg, W.; Konings, A. G.; Trugman, A. T.; Pacala, S. W.; Yu, K.; Sulman, B. N.; Sperry, J.; Bowling, D. R.

2017-12-01

Drought impacts carbon, water, and energy cycles in forests and may pose a fundamental threat to forests in future climates. Plant hydraulic transport of water is central to tree drought responses, including curtailing of water loss and the risk of mortality during drought. The effect of biodiversity on ecosystem function has typically been examined in grasslands, yet the diversity of plant hydraulic strategies may influence forests' response to drought. In a combined analysis of eddy covariance measurements, remote-sensing data of plant water content variation, model simulations, and plant hydraulic trait data, we test the degree to which plant water stress schemes influence the carbon cycle and how hydraulic diversity within and across ecosystems affects large-scale drought responses. We find that current plant functional types are not well-suited to capture hydraulic variation and that higher hydraulic diversity buffers ecosystem variation during drought. Our results demonstrate that tree functional diversity, particularly hydraulic diversity, may be critical to simulate in plant functional types in current land surface model projections of future vegetation's response to climate extremes.

[Distribution of potentially nitrogen-fixing bacteria and its relationship with physicochemical parameters in soils with three vegetation types in the southern Colombian Amazon region].

PubMed

Mantilla-Paredes, Andrea J; Cardona, Gladys I; Peña-Venegas, Clara P; Murcia, Uriel; Rodríguez, Mariana; Zambrano, Maria M

2009-12-01

Potentially nitrogen-fixing microaerobic and aerobic bacteria were isolated from several Colombian Amazon soils (forest, pastures and chagras) and two landscapes (floodable and non floodable areas). The abundance and distribution of bacteria were evaluated, as well as their relationship with soil physical and chemical characteristics. Landscape had a direct influence on the abundance of the microaerobic bacteria, with higher numbers in forest and pasture soils in non-floodable zones. The aerobic isolates (N=51) were grouped into 19 morphologies, with the highest numbers found in forest soil in floodable zones. A higher number of aerobic morphologies was shared among forest sites (Nonmetric Multidimensional Scaling and Analysis of Similarity p<0.05), and 40% of the distribution was explained by lime percentage and Al concentration.

Hybridization of mouse lemurs: different patterns under different ecological conditions

PubMed Central

2011-01-01

Background Several mechanistic models aim to explain the diversification of the multitude of endemic species on Madagascar. The island's biogeographic history probably offered numerous opportunities for secondary contact and subsequent hybridization. Existing diversification models do not consider a possible role of these processes. One key question for a better understanding of their potential importance is how they are influenced by different environmental settings. Here, we characterized a contact zone between two species of mouse lemurs, Microcebus griseorufus and M. murinus, in dry spiny bush and mesic gallery forest that border each other sharply without intermediate habitats between them. We performed population genetic analyses based on mtDNA sequences and nine nuclear microsatellites and compared the results to a known hybrid zone of the same species in a nearby wide gradient from dry spiny bush over transitional forest to humid littoral forest. Results In the spiny-gallery system, Microcebus griseorufus is restricted to the spiny bush; Microcebus murinus occurs in gallery forest and locally invades the dryer habitat of its congener. We found evidence for bidirectional introgressive hybridization, which is closely linked to increased spatial overlap within the spiny bush. Within 159 individuals, we observed 18 hybrids with mitochondrial haplotypes of both species. Analyses of simulated microsatellite data indicate that we identified hybrids with great accuracy and that we probably underestimated their true number. We discuss short-term climatic fluctuations as potential trigger for the dynamic of invasion and subsequent hybridization. In the gradient hybrid zone in turn, long-term aridification could have favored unidirectional nuclear introgression from Microcebus griseorufus into M. murinus in transitional forest. Conclusions Madagascar's southeastern transitional zone harbors two very different hybrid zones of mouse lemurs in different environmental settings. This sheds light on the multitude of opportunities for the formation of hybrid zones and indicates an important influence of environmental factors on secondary contact and hybridization. Our findings suggest that hybridization could enhance the adaptability of mouse lemurs without necessarily leading to a loss of distinctiveness. They point to a potential role of hybridization in Madagascar's diversification history that requires further investigation. PMID:21989384

Supplemental Planting of Early Successional Tree Species During Bottomland Hardwood Afforestation

Treesearch

Daniel J. Twedt; R. Randy Wilson

2002-01-01

Reforestation of former bottomland hardwood forests that have been cleared for agriculture (i.e., afforestation) has historically emphasized planting heavy-seeded oaks (Quercus spp.) and pecans (Carya spp.). These species are slow to develop vertical forest structure. However, vertical forest structure is key to colonization of...

Determining effective riparian buffer width for nonnative plant exclusion and habitat enhancement

Treesearch

Gavin Ferris; Vincent D' Amico; Christopher K. Williams

2012-01-01

Nonnative plants threaten native biodiversity in landscapes where habitats are fragmented. Unfortunately, in developed areas, much of the remaining forested habitat occurs in fragmented riparian corridors. Because forested corridors of sufficient width may allow forest interior specializing native species to retain competitive advantage over edge specialist and...

Comparison of emerging contaminants in receiving waters downstream of a conventional wastewater treatment plant and a forest-water reuse system

EPA Science Inventory

Forest-water reuse (FWR) systems treat municipal, industrial, and agricultural wastewaters via land application to forest soils. Previous studies have shown that both large-scale conventional wastewater treatment plants (WWTPs) and FWR systems do not completely remove many contam...

Structure and composition of altered riparian forests in an agricultural Amazonian landscape.

PubMed

Nagy, R Chelsea; Porder, Stephen; Neill, Christopher; Brando, Paulo; Quintino, Raimundo Mota; do Nascimento, Sebastiâo Aviz

2015-09-01

Deforestation and fragmentation influence the microclimate, vegetation structure, and composition of remaining patches of tropical forest. In the southern Amazon, at the frontier of cropland expansion, forests are converted and fragmented in a pattern that leaves standing riparian forests whose dimensions are mandated by the Brazilian National Forest Code. These altered riparian forests share many characteristics of well-studied upland forest fragments, but differ because they remain connected to larger areas of forest downstream, and because they may experience wetter soil conditions because reduction of forest cover in the surrounding watershed raises groundwater levels and increases stream runoff. We compared forest regeneration, structure, composition, and diversity in four areas of intact riparian forest and four areas each of narrow, medium, and wide altered riparian forests that have been surrounded by agriculture since the early 1980s. We found that seedling abundance was reduced by as much as 64% and sapling abundance was reduced by as much as 67% in altered compared to intact riparian forests. The most pronounced differences between altered and intact forest occurred near forest edges and within the narrowest sections of altered riparian forests. Woody plant species composition differed and diversity was reduced in altered forests compared to intact riparian forests. However, despite being fragmented for several decades, large woody plant biomass and carbon storage, the number of live or dead large woody plants, mortality rates, and the size distribution of woody plants did not differ significantly between altered and intact riparian forests. Thus, even in these relatively narrow forests with high edge: area ratios, we saw no evidence of the increases in mortality and declines in biomass that have been found in other tropical forest fragment studies. However, because of the changes in both species community and reduced regeneration, it is unclear how long this relative lack of change will be sustained. Additionally, Brazil recently passed a law in their National Forest Code allowing narrower riparian buffers than those studied here in restored areas, which could affect their long-term sustainability.

Effects of land use and climate change on ecosystem services in Central Asia's arid regions: A case study in Altay Prefecture, China.

PubMed

Fu, Qi; Li, Bo; Hou, Ying; Bi, Xu; Zhang, Xinshi

2017-12-31

The sustainable use of ecosystem services (ES) can contribute to enhancing human well-being. Understanding the effects of land use and climate change on ES can provide scientific and targeted guidance for the sustainable use of ES. The objective of this study was to reveal the way in which land use and climate change influence the spatial and temporal variations of ES in the mountain-oasis-desert system (MODS). In this study, we assessed water yield, soil conservation, crop production, and sand fixation in 1990, 2000, and 2010 in Altay Prefecture, which is representative of the MODS, based on widely used biophysical models. Moreover, we analyzed the effects of different land use and climate change conditions on ES. The results show that the area of forest and bare land decreased in Altay Prefecture. In contrast, the area of grassland with low coverage and cropland increased. The climate of this area presented an overall warming-wetting trend, with warming-drying and cooling-wetting phenomena in some areas. Soil conservation in the mountain zone, water yield in the oasis zone, and sand fixation in the desert zone all decreased under the influence of land use change alone. The warming-drying trend led to decreased water yield in the oasis zone and increased wind erosion in the desert zone. Based on the results, we recommend that local governments achieve sustainable use of ES by planting grasslands with high coverage in the oasis zone, increasing investment in agricultural science and technology, and establishing protected areas in the mountain and desert zones. The methodology in our study can also be applied to other regions with a MODS structure. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of mangrove species using ALOS-2 PALSAR in Hai Phong city, Vietnam

NASA Astrophysics Data System (ADS)

Dat Pham, Tien; Yoshino, Kunihiko

2016-06-01

Hai Phong city is located in the Northern coast of Vietnam where the mangroves are distributed between zone I and zone II among the four mangrove zones in Vietnam. This city is vulnerable to rising sea levels associated with climate change and tropical cyclones, which are forecasted to become more severe due to the impact of climate change. In the past, mangrove forests in this city have decreased markedly because of over expansion of shrimp farming. Thus, identification of mangrove forests is important to monitor and support mangrove conservation and management in the coastal zone. The objectives of this research were to identify the locations of mangrove and characterize mangrove species in Hai Phong using HH and HV backscatters of the Advanced Land Observing Satellite 2 (ALOS-2) with enhanced Phased Array L-band Synthetic Aperture Radar (PALSAR). Image segmentation was used to identify the locations of mangrove forests. Moreover, Geographic Information System (GIS) was applied to update current status of mangrove species in 2015. The results showed that the means of HH and HV backscatter coefficients of K. obovata are lower than S. caseolaris. K. obovata has HH value around -13.9 dB until -10.3 dB and HV value around -20.6 dB until -16.2 dB. Higher HH values between about -14.9 dB and -6.8 dB and HV values between roughly -20.6 dB and -14.3 dB have observed by S. caseolaris. The total area of mangrove forest in Hai Phong in the year 2015 was around 4084 hectares, of which S. caseolaris occupied over 68% and mixed mangrove species was approximately 25.6%. This research indicates the potential for the use of L-band ALOS-2 PALSAR in characterizing mangrove forest species in the coastal zone.

Using soundscapes to detect variable degrees of human influence on tropical forests in Papua New Guinea.

PubMed

Burivalova, Zuzana; Towsey, Michael; Boucher, Tim; Truskinger, Anthony; Apelis, Cosmas; Roe, Paul; Game, Edward T

2018-02-01

There is global concern about tropical forest degradation, in part, because of the associated loss of biodiversity. Communities and indigenous people play a fundamental role in tropical forest management and are often efficient at preventing forest degradation. However, monitoring changes in biodiversity due to degradation, especially at a scale appropriate to local tropical forest management, is plagued by difficulties, including the need for expert training, inconsistencies across observers, and lack of baseline or reference data. We used a new biodiversity remote-sensing technology, the recording of soundscapes, to test whether the acoustic saturation of a tropical forest in Papua New Guinea decreases as land-use intensity by the communities that manage the forest increases. We sampled soundscapes continuously for 24 hours at 34 sites in different land-use zones of 3 communities. Land-use zones where forest cover was fully retained had significantly higher soundscape saturation during peak acoustic activity times (i.e., dawn and dusk chorus) compared with land-use types with fragmented forest cover. We conclude that, in Papua New Guinea, the relatively simple measure of soundscape saturation may provide a cheap, objective, reproducible, and effective tool for monitoring tropical forest deviation from an intact state, particularly if it is used to detect the presence of intact dawn and dusk choruses. © 2017 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

140-Year Dynamics of a Forest Ecotone Under Climate and Environmental Change

NASA Astrophysics Data System (ADS)

Thorne, J. H.; Kelsey, R.

2006-12-01

Terrestrial plant species live within elevational limits. Response to climate change at the lower edge of a species' range can be quite different from response at its upper limits. Lower edge dynamics can sometimes lead to rapid shifts, if establishment conditions have changed. Under those circumstances, stand replacing disturbances can cause the local extirpation of the species because subsequent recruitment is ineffectual. We examined the position of lower edge of Pinus ponderosa forests in El Dorado County, California, where the tree occupies a broad elevational gradient. We found that over 140 years, this forest had shifted upslope over 500 meters. Minimum monthly air temperatures from stations forming an elevational transect in these mountains have warmed over the past 60 years by over 30 C. In the zone of the shift, this means that now no months are frozen, whereas 60 years ago December, January and February were below 00C. This warming is associated with advancing summer drought conditions, which set the stage for drought stress and reduced competitive abilities in the seedlings. We present an estimate for how much sooner summer drought conditions begin. Potential confounding factors: including grazing, agriculture, fires and urban expansion were found to occupy only 40% of the 540 km2 of forests lost since 1850 in the County. Forest change here is a disturbance initiated, recruitment limited system. Implications of this research include that the lower edge of coniferous systems are sensitive to climate change, via a combination of direct and indirect effects. A possible feedback between this edge and the lower limits of the snowline is discussed.

The influence of plant communities on postagrogenic soils in the middle taiga zone.

NASA Astrophysics Data System (ADS)

Churilin, Nikita; Churilina, Alexandra; Chizhikova, Natalia; Varlamov, Evgeny

2016-04-01

At the present time there are many abandoned postagrogenic croplands in Russia. These lands are gradually involved in natural plant succession, which has affect on the properties of the soil. Therefore, the study of these soils is one of the important trends in the Russian soil science. The aim of the study was to identify possible trends in soil changes after a long anthropogenic impact on a base of morphological, chemical and some physical properties of postagrogenic soils under different plant communities. Soils were sampled in the south of Arkhangelsk region, Ustyansky district, near Akichkin Pochinok village. Soils are formed on clay moraine of Moscow glaciation with klastolits. All soil profiles were dug on interfluve. We determined chemical composition (pH, CaCO3%, organic carbon, CEC, F2O3 (Mer-Jackson), NPK), physical characteristics (particle size distribution, bulk density of the soil) and XRD of <1μm, 1-5μm, 5-10μm fractions from soils. We selected 4 plant communities on different stages of succession: upland meadow with domination of sod grasses (Phleum pratense, Agrostis tenuis), 16 years old birch forest where dominatants are herbaceous plants such as Poa sp., Chamerion angustiflium, Agrostis tenuis, 16 years old spruce forest with no herbaceous vegetation and 70 years old bilberry spruce forest with domination of Vaccinium myrtillus and Vaccinium vitis-idaea. To study postagrogenic soils we made 4 soil profiles under these plant communities. All profiles have evidence of anthraquic horizon and they have plough pan on a depth of 20-24 cm (confirmed by bulk density). The plowed horizon is better expressed in soils under the meadow. All 4 soils are characterized by presence of Fe-Mn segregations throughout the profiles, particle size distribution heaving to the lower horizon and residual albic horizon. We identified following soils: Albic Dystric Retisol (Cutanic Abrubptic Loamic) under the old spruce, Dystric Retisol (Cutanic Loamic Anthraquic) in young spruce, Glossic Albic Dystric Retisol (Cutanic Loamic Anthraquic) in young birch forest and Dystric Retisol (Loamic Abruptic Anthraquic) under upland meadow. We found a correlation between amount of clay fraction in upper horizons (<20 cm) of these soils and crown density: the amount of clay increases with density of branches. This trend can be explained by the fact that amount of precipitation on the surface of the soil decreases with crown density, therefore clay doesn't migrate to the underlying horizons in the soil. Over time, acid aqueous solution can influence on process of clay fraction redistribution, so it explains the reduction of clay content in the old spruce forest and well-defined albic horizon. The results of chemical analyses showed that pH of these soils varies between 3 and 4. In all soils we can see illuvial accumulation of P2O5, exchangeable bases, K2O, Fe2O3. It was also shown that carbonates are present in horizons close to the subsoil, which content is less than 1%.

Dynamics of nitrogen and dissolved organic carbon at the Hubbard brook experimental forest.

PubMed

Dittman, Jason A; Driscoll, Charles T; Groffman, Peter M; Fahey, Timothy J

2007-05-01

The factors controlling spatial and temporal patterns in soil solution and streamwater chemistry are highly uncertain in northern hardwood forest ecosystems in the northeastern United States, where concentrations of reactive nitrogen (Nr) in streams have surprisingly declined over recent decades in the face of persistent high rates of atmospheric Nr deposition and aging forests. Reactive nitrogen includes inorganic species (e.g., ammonium [NH4+], nitrate [NO3-]) and some organic forms (e.g., amino acids) available to support the growth of plants and microbes. The objective of this study was to examine controls on the spatial and temporal patterns in the concentrations and fluxes of nitrogen (N) species and dissolved organic carbon (DOC) in a 12-year record of soil solutions and streamwater along an elevational gradient (540-800 m) of a forested watershed at the Hubbard Brook Experimental Forest (HBEF) in the White Mountains of New Hampshire, USA. Dissolved organic N and DOC concentrations were elevated in the high-elevation spruce-fir-white birch (SFB) zone of the watershed, while NO3- was the dominant N species in the lower elevation hardwood portion of the watershed. Within the soil profile, N retention was centered in the mineral horizon, and significant amounts of N were retained between the lower mineral soil and the stream, supporting the idea that near- and in-stream processes are significant sinks for N at the HBEF. Temporal analysis suggested that hydrologic flow paths can override both abiotic and biotic retention mechanisms (i.e., during the non-growing season when most hydrologic export occurs, or during years with high rainfall), there appears to be direct flushing of N from the organic horizons into the stream via horizontal flow. Significant correlations between soil NO3- concentrations, nitrification rates and streamwater NO3- exports show the importance of biological production as a regulator of inorganic N export. The lack of internal production response (e.g., mineralization, nitrification) to a severe ice storm in 1998 reinforces the idea that plant uptake is the dominant regulator of export response to disturbance.

Silviculture for restoration of degraded temperate and boreal forests

Treesearch

John A. Stanturf; Palle Madsen; Emile S. Gardiner

2004-01-01

Throughout the temperate and boreal zones, human intervention has influenced landscapes and forests for millennia. The degree of human disturbance has only been constrained by the technology and resources available to different cultures and by time since initial habitation. Humans have influenced forests by regulating populations of browsers, clearing for agriculture,...

Maintaining forest diversity in a changing climate: A geophysical approach

Treesearch

Mark Anderson; Nels Johnson; Scott Bearer

2014-01-01

Forest conservationists need a method to conserve the maximum amount of biological diversity while allowing species and communities to rearrange in response to a continually changing climate. Here, we develop such an approach for northeastern North America. First we characterize and categorize forest blocks based on their geology, landforms, and elevation zones. Next,...

76 FR 24511 - Cabo Rojo National Wildlife Refuge, Cabo Rojo, Puerto Rico; Draft Comprehensive Conservation Plan...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-02

... the Gu[aacute]nica Commonwealth Forest remaining in public ownership. The native vegetation is classified as subtropical dry forest under the Holdridge classification of world life zones. At least 245... restore and maintain existing sub-tropical dryland forests, salt lagoons, and grassland habitats. Active...

Potential for spatial management of hunted mammal populations in tropical forests

Treesearch

Miranda H. Mockrin; Kent H. Redford

2011-01-01

Unsustainable hunting in tropical forests threatens biodiversity and rural livelihoods, yet managing these harvests in remote forests with low scientific capacity and funding is challenging. In response, some conservationists propose managing harvests through spatial management, a system of establishing notake zones where hunting is not allowed. Spatial management was...

75 FR 8297 - Tongass National Forest, Thorne Bay Ranger District, Thorne Bay, AK

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-24

..., Thorne Bay, AK AGENCY: Forest Service, USDA. ACTION: Cancellation of Notice of intent to prepare an... Roberts, Zone Planner, Thorne Bay Ranger District, Tongass National Forest, P.O. Box 19001, Thorne Bay, AK 99919, telephone: 907-828-3250. SUPPLEMENTARY INFORMATION: The 47,007-acre Kosciusko Project Area is...

Species richness and soil properties in Pinus ponderosa forests: A structural equation modeling analysis

USGS Publications Warehouse

Laughlin, D.C.; Abella, S.R.; Covington, W.W.; Grace, J.B.

2007-01-01

Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a Pinus ponderosa (ponderosa pine) forest ecosystem. We evaluated multivariate models of plant species richness using structural equation modeling. Results: Richness was highest at intermediate levels of understory plant cover, suggesting that both colonization success and competitive exclusion can limit richness in this system. We did not detect a reciprocal positive effect of richness on plant cover. Richness was strongly related to soil nitrogen in the model, with evidence for both a direct negative effect and an indirect non-linear relationship mediated through understory plant cover. Soil organic matter appeared to have a positive influence on understory richness that was independent of soil nitrogen. Richness was lowest where the forest overstory was densest, which can be explained through indirect effects on soil organic matter, soil nitrogen and understory cover. Finally, model results suggest a variety of direct and indirect processes whereby mineral soil properties can influence richness. Conclusions: Understory plant species richness and plant cover in P. ponderosa forests appear to be significantly influenced by soil organic matter and nitrogen, which are, in turn, related to overstory density and composition and mineral soil properties. Thus, soil properties can impose direct and indirect constraints on local species diversity in ponderosa pine forests. ?? IAVS; Opulus Press.

Isotopes and soil physic analysis as a tool to meet answers related to soil-plant-atmosphere behavior of Amazon forest during droughts

NASA Astrophysics Data System (ADS)

Borma, L. D. S.; Oliveira, R. S.; Silva, R. D.; Chaparro Saaveedra, O. F.; Barros, F. V.; Bittencourt, P.

2015-12-01

Droughts and floods are part of the Amazon weather pattern, but in face of climate change, it has been expected an increase in their intensity and duration. Forests are important regulators of climate. However, it is still unknown how they respond to an increase in frequency and intensity of extreme droughts. Additionally, there are great uncertainties related with the forest behavior in an enriched CO2 environment. For the Amazon rainforest, some authors report forest growth in a drier climate, while others report forest mortality in these same conditions. The crucial factor in this process seem the linkage between atmospheric demand from water and its provision by soil moisture, intermediated by the plants. In theory, in regions where soil moisture is high, even in the absence of rainfall conditions, water exists in enough quantity to meet the atmospheric demand, and majority of plants behave as an evergreen forest. This is the case, for example, for some research sites of equatorial regions of the Amazon forest, which tend to increase evapotranspiration rates in dry season, when the atmospheric demand is higher. However, the extent to which soil moisture decreases, the plant is no longer able to meet the atmospheric demand, limiting evapotranspiration and possibly, entering in a dormant state. To understand the forest response to droughts, in terms of its potential to maintain or reduce evapotranspiration rates, it is necessary to know water dynamics in soil and soil layers where plants are able to extract water. It's a challenge, considering the great variability of soils and plants that forms the huge biodiversity of the Amazon forest. Here, we present an experiment design based on isotopic analyzes in a small watershed in Amazon basin. In order to understand the dynamics of the water used by the plant during the evaporation process, isotope analysis were carried out in soil water collected from shallow and deep groundwater, in the water collected on the bark of plants and rainfall water, intercepted or not by the canopy. These results were analyzed in conjunction with the soil properties, its moisture retention capacity and groundwater level variations. This study presents some insights about the capability of this methodology to answer questions related to the soil moisture sources and forest response to droughts.

Therapeutic efficacy of artesunate-amodiaquine and artemether-lumefantrine combinations in the treatment of uncomplicated malaria in two ecological zones in Ghana.

PubMed

Abuaku, Benjamin; Duah, Nancy; Quaye, Lydia; Quashie, Neils; Malm, Keziah; Bart-Plange, Constance; Koram, Kwadwo

2016-01-05

Case management based on prompt diagnosis and adequate treatment using artemisinin-based combination therapy (ACT) remains the main focus of malaria control in Ghana. As part of routine surveillance on the therapeutic efficacy of ACT in Ghana, the efficacy of amodiaquine-artesunate (AS-AQ) and artemether-lumefantrine (AL) were studied in six sentinel sites representing the forest and savannah zones of the country. Three sites representing the two ecological zones studied AS-AQ whilst the other three sites studied AL. In each site, the study was a one-arm prospective evaluation of the clinical, parasitological, and haematological responses to directly observed therapy for uncomplicated malaria with either AS-AQ or AL among children aged 6 months and 9 years. The WHO 2009 protocol for monitoring anti-malarial drug efficacy was used for the study between July 2013 and March 2014. Per-protocol analyses on day 28 showed an overall PCR-corrected cure rate of 100% for AS-AQ and 97.6% (95% CI 93.1, 99.5) for AL: 97.2% (95% CI 92.0, 99.4) in the forest zone and 100% in the savannah zone. Kaplan-Meier survival analysis showed similar outcomes. Prevalence of fever decreased by about 75% after the first day of treatment with each ACT in the two ecological zones. No child studied was parasitaemic on day 3, and gametocytaemia was generally maintained at low levels (<5%). Post-treatment mean haemoglobin concentrations significantly increased in the two ecological zones. Therapeutic efficacy of AS-AQ and AL remains over 90% in the forest and savannah zones of Ghana. Additionally, post-treatment parasitaemia on day 3 is rare suggesting that artemisinin is still efficacious in Ghana.

The source of dissolved silicon in soil surface solutions of a temperate forest ecosystem: Ge/Si and Si isotope ratios as biogeochemical tracers

NASA Astrophysics Data System (ADS)

Cornelis, J.; Delvaux, B.; Cardinal, D.; André, L.; Ranger, J.; Opfergelt, S.

2010-12-01

Understand the biogeochemical cycle of silicon (Si) in the Earth’s critical zone and the dissolved Si transfer from the litho-pedosphere into the hydrosphere is of great interest for the global balance of biogeochemical processes, including the global C cycle. Indeed, the interaction between Si and C cycles regulates the atmospheric CO2 through the chemical weathering of silicate minerals, the C sequestration in stable organo-mineral compounds and the Si nutrition of phytoplankton CO2-consumers in oceans. H4SiO4 released by mineral dissolution contributes to the critical zone evolution through neoformation of secondary minerals, adsorption onto hydroxyl-bearing phases and recycling by vegetation and return of phytoliths on topsoil. The neoformation of secondary precipitates (clay minerals and phytoliths polymerized in plants) and adsorption of Si onto Fe and Al (hydr)oxides are processes favoring the light Si isotope incorporation, generating rivers enriched in heavy Si isotopes. On the other hand, clay minerals and phytoliths display contrasting Ge/Si ratios since clay-sized weathering products are enriched in Ge and phytoliths are depleted in Ge. Thus stable Si isotope and Ge/Si ratios constitute very interesting proxies to trace transfer of Si in the critical zone. Here we report Si isotopic and Ge/Si ratios of the different Si pools in a temperate soil-tree system (Breuil experimental forest, France) involving various tree species grown on Alumnic Cambisol derived from granitic bedrock. Relative to granitic bedrock (δ30Si = -0.07 ‰; Ge/Si = 2.5 µmol/mol), clay-sized minerals are enriched in 28Si (-1.07 ‰) and Ge (6.2 µmol/mol) while phytoliths are enriched in 28Si (-0.28 to -0.64 ‰) and depleted in Ge (0.1 to 0.3 µmol/mol). This contrast allows us to infer the relative contribution of litho/pedogenic and biogenic mineral dissolution on the release of H4SiO4 in soil surface solutions. The Si-isotope signatures and Ge/Si ratios of forest floor solutions evolve towards lighter values (-1.38 and -2.05 ‰) and higher Ge/Si ratios (2.7 µmol/mol) relative to granite bedrock. This suggests a partial dissolution of 28Si and Ge-enriched secondary clays minerals incorporated by bioturbation in organic-rich horizons, with a fractionation releasing preferentially light Si isotopes. Without considering that organic acids promote dissolution of minerals, clay minerals detected in the organic layer (vermiculite, chlorite, illite and Ca-montmorillonite) are not stable and could have been partially dissolved and transformed in the chemical environment of forest floor. Sources of H4SiO4 in forest floor solutions are influenced by tree species which control the extent of clay-sized minerals mixed in organic horizons by bioturbation and, to a lesser extent, the Si recycling by forest vegetation.

Live plant imports: the major pathway for forest insect and pathogen invasions of the US

Treesearch

Andrew M. Liebhold; Eckehard G. Brockerhoff; Lynn J. Garrett; Jennifer L. Parke

2012-01-01

Trade in live plants has been recognized worldwide as an important invasion pathway for non-native plant pests. Such pests can have severe economic and ecological consequences. Nearly 70% of damaging forest insects and pathogens established in the US between 1860 and 2006 most likely entered on imported live plants. The current regulation of plant imports is outdated...

Plantings on the forest reserves of Hawaii, 1910-1960

Treesearch

Roger G. Skolmen

1980-01-01

This is a listing of the recorded plantings made by the Hawaii division of forestry between the years 1910 and 1960 on government and privately-owned lands within the forest reserves and on certain islands offshore of Oahu. The listing provides: scientific and common names of each plant, type of plant, nomenclature reference, suitability of the plant for Hawaii’s...

Understory plant development in artificial canopy gaps in an 81-year-old forest stand on Chichagof Island, southeast Alaska

Treesearch

Scott Harris; Jeffrey Barnard

2017-01-01

This study assesses the understory plant response and associated effects on forage resources available to Sitka black-tailed deer (Odocoileus hemionus sitkensis), to the creation of artificial canopy gaps in a young-growth forest stand in the coastal temperate rain forest of southeast Alaska. The forest stand was approximately 58 years old when gaps were created and...

Light accelerates plant responses to warming.

PubMed

De Frenne, Pieter; Rodríguez-Sánchez, Francisco; De Schrijver, An; Coomes, David A; Hermy, Martin; Vangansbeke, Pieter; Verheyen, Kris

2015-08-17

Competition for light has profound effects on plant performance in virtually all terrestrial ecosystems. Nowhere is this more evident than in forests, where trees create environmental heterogeneity that shapes the dynamics of forest-floor communities(1-3). Observational evidence suggests that biotic responses to both anthropogenic global warming and nitrogen pollution may be attenuated by the shading effects of trees and shrubs(4-9). Here we show experimentally that tree shade is slowing down changes in below-canopy communities due to warming. We manipulated levels of photosynthetically active radiation, temperature and nitrogen, alone and in combination, in a temperate forest understorey over a 3-year period, and monitored the composition of the understorey community. Light addition, but not nitrogen enrichment, accelerated directional plant community responses to warming, increasing the dominance of warmth-preferring taxa over cold-tolerant plants (a process described as thermophilization(6,10-12)). Tall, competitive plants took greatest advantage of the combination of elevated temperature and light. Warming of the forest floor did not result in strong community thermophilization unless light was also increased. Our findings suggest that the maintenance of locally closed canopy conditions could reduce, at least temporarily, warming-induced changes in forest floor plant communities.

Combined fluorescence, reflectance, and ground measurements of a stressed Norway spruce forest for forest damage assessment

NASA Technical Reports Server (NTRS)

Banninger, C.

1991-01-01

The detection and monitoring of stress and damage in forested areas is of utmost importance to forest managers for planning purposes. Remote sensing are the most suitable means to obtain this information. This requires that remote sensing data employed in a forest survey be properly chosen and utilized for their ability to measure canopy spectral features directly related to key tree and canopy properties that are indicators of forest health and vitality. Plant reflectance in the visible to short wave IR regions (400 to 2500 nm) provides information on its biochemical, biophysical, and morphological make up, whereas plant fluorescence in the 400 to 750 nm region is more indicative of the capacity and functioning of its photosynthetic apparatus. A measure of both these spectral properties can be used to provide an accurate assessment of stress and damage within the forest canopy. Foliar chlorophyll and nitrogen are essential biochemical constituents required for the proper functioning and maintenance of a plant's biological processes. Chlorophyll-a is the prime reactive center for photosynthesis, by which a plant converts CO2 and H2O into necessary plant products. Nitrogen forms an important component of the amino-acids, enzymes, proteins, alkaloids, and cyanogenic compounds that make up a plant, including its pigments. Both chlorophyll and nitrogen have characteristic absorption features in the visible to short wave IR region. By measuring the wavelength position and depth of these features and the fluorescence response of the foliage, the health and vitality of a canopy can be ascertained. Examples for a stressed Norway spruce forest in south-eastern Austria are presented.

Effect of the historical land use on the structure of forest soils in European Russia

NASA Astrophysics Data System (ADS)

Bobrovskii, M. V.

2010-12-01

The morphological structure of the soils in the forest areas of European Russia was analyzed. It was shown that most of the soils were formed under the impact of both biotic and anthropogenic factors. Soils with poorly differentiated profiles without podzolization features are typical for the least disturbed forest ecosystems. The presence of an eluvial (EL) horizon is associated with the signs of old plowing and (or) fires. The character and rate of the soil cover transformation under various impacts of the historical land use (felling, plowing, pasturing, burning, etc.) are discussed. The technologies of the main traditional farming systems in the forest zone of European Russia (slash-and-burn, fallow, and shifting farming systems) are considered; their effect on the long-term dynamics of the soil cover is estimated. Farming and the related impacts of historical land use can be a major reason for the formation of degraded soils in the forest zone of European Russia.

Effects of warming on ectomycorrhizal colonization and nitrogen nutrition of Picea asperata seedlings grown in two contrasting forest ecosystems

PubMed Central

Li, Yuejiao; Sun, Didi; Li, Dandan; Xu, Zhenfeng; Zhao, Chunzhang; Lin, Honghui; Liu, Qing

2015-01-01

Ectomycorrhiza (ECM) plays an important role in plant nitrogen (N) nutrition and regulates plant responded to climate warming. We conducted a field experiment in a natural forest and a plantation in the eastern Tibetan Plateau to estimate the warming effects of open-top chambers (OTC) on ECM and N nutrition of Picea asperata seedlings. Four-year warming significantly decreased ECM colonization, ECM fungal biomass, fine root vigor, and the N concentration of leaf, stem and coarse root, but significantly increased fine root N concentration and N content of leaf, stem, fine root and whole plant in natural forest. Contrarily, warming induced no obvious change in most of these parameters in plantation. Moreover, warming decreased rhizospheric soil inorganic N content in both forests. Our results showed that four-year warming was not beneficial for ECM colonization of P. asperata seedlings in the two forests, and the seedlings in natural forest were more sensitive and flexible to experimental warming than in plantation. The changes of ECM colonization and fine root biomass for effective N uptake would be good for plant growth and remit N leaching under future warming in natural forest. PMID:26655633

Understory plant communities and the functional distinction between savanna trees, forest trees, and pines

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

Veldman, Joseph W.; Mattingly, W. Brett; Brudvig, Lars A.

Although savanna trees and forest trees are thought to represent distinct functional groups with different effects on ecosystem processes, few empirical studies have examined these effects. In particular, it remains unclear if savanna and forest trees differ in their ability to coexist with understory plants, which comprise the majority of plant diversity in most savannas. We used structural equation modeling (SEM) and data from 157 sites across three locations in the southeastern United States to understand the effects of broadleaf savanna trees, broadleaf forest trees, and pine trees on savanna understory plant communities. After accounting for underlying gradients in firemore » frequency and soil moisture, abundances (i.e., basal area and stem density) of forest trees and pines, but not savanna trees, were negatively correlated with the cover and density (i.e., local-scale species richness) of C4 graminoid species, a defining savanna understory functional group that is linked to ecosystem flammability. In analyses of the full understory community, abundances of trees from all functional groups were negatively correlated with species density and cover. For both the C4 and full communities, fire frequency promoted understory plants directly, and indirectly by limiting forest tree abundance. There was little indirect influence of fire on the understory mediated through savanna trees and pines, which are more fire tolerant than forest trees. We conclude that tree functional identity is an important factor that influences overstory tree relationships with savanna understory plant communities. In particular, distinct relationships between trees and C4 graminoids have implications for grass-tree coexistence and vegetation-fire feedbacks that maintain savanna environments and their associated understory plant diversity.« less

Integration of Satellite Tracking Data and Satellite Images for Detailed Characteristics of Wildlife Habitats

NASA Astrophysics Data System (ADS)

Dobrynin, D. V.; Rozhnov, V. V.; Saveliev, A. A.; Sukhova, O. V.; Yachmennikova, A. A.

2017-12-01

Methods of analysis of the results got from satellite tracking of large terrestrial mammals differ in the level of their integration with additional geographic data. The reliable fine-scale cartographic basis for assessing specific wildlife habitats can be developed through the interpretation of multispectral remote sensing data and extrapolation of the results to the entire estimated species range. Topographic maps were ordinated according to classified features using self-organizing maps (Kohonen's SOM). The satellite image of the Ussuriiskyi Nature Reserve area was interpreted for the analysis of movement conditions for seven wild Amur tigers ( Panthera tigris altaica) equipped with GPS collars. 225 SOM classes for cartographic visualization are sufficient for the detailed mapping of all natural complexes that were identified as a result of interpretation. During snow-free periods, tigers preferred deciduous and shrub associations at lower elevations, as well as mixed forests in the valleys of streams that are adjacent to sparse forests and shrub watershed in the mountain ranges; during heavy snow periods, the animals preferred the entire range of plant communities in different relief types, except for open sites in meadows and abandoned fields at foothills. The border zones of different biotopes were typically used by the tigers during all seasons. Amur tigers preferred coniferous forests for long-term movements.

Ecological constraints increase the climatic debt in forests

PubMed Central

Bertrand, Romain; Riofrío-Dillon, Gabriela; Lenoir, Jonathan; Drapier, Jacques; de Ruffray, Patrice; Gégout, Jean-Claude; Loreau, Michel

2016-01-01

Biodiversity changes are lagging behind current climate warming. The underlying determinants of this climatic debt are unknown and yet critical to understand the impacts of climate change on the present biota and improve forecasts of biodiversity changes. Here we assess determinants of climatic debt accumulated in French forest herbaceous plant communities between 1987 and 2008 (that is, a 1.05 °C mean difference between the observed and bioindicated temperatures). We show that warmer baseline conditions predispose plant communities to larger climatic debts, and that climate warming exacerbates this response. Forest plant communities, however, are absorbing part of the temperature increase mainly through the species' ability to tolerate changing climate. As climate warming is expected to accelerate during the twenty-first century, plant migration and tolerance to climatic stresses probably will be insufficient to absorb this impact posing threats to the sustainability of forest plant communities. PMID:27561410