Computer model of hydroponics nutrient solution pH control using ammonium.

PubMed

Pitts, M; Stutte, G

1999-01-01

A computer simulation of a hydroponics-based plant growth chamber using ammonium to control pH was constructed to determine the feasibility of such a system. In nitrate-based recirculating hydroponics systems, the pH will increase as plants release hydroxide ions into the nutrient solution to maintain plant charge balance. Ammonium is an attractive alternative to traditional pH controls in an ALSS, but requires careful monitoring and control to avoid overdosing the plants with ammonium. The primary advantage of using NH4+ for pH control is that it exploits the existing plant nutrient uptake charge balance mechanisms to maintain solution pH. The simulation models growth, nitrogen uptake, and pH of a l-m2 stand of wheat. Simulation results indicated that ammonium-based control of nutrient solution pH is feasible using a proportional integral controller. Use of a 1 mmol/L buffer (Ka = 1.6 x 10(-6)) in the nutrient solution is required.

Particle water and pH in the eastern Mediterranean: source variability and implications for nutrient availability

NASA Astrophysics Data System (ADS)

Bougiatioti, Aikaterini; Nikolaou, Panayiota; Stavroulas, Iasonas; Kouvarakis, Giorgos; Weber, Rodney; Nenes, Athanasios; Kanakidou, Maria; Mihalopoulos, Nikolaos

2016-04-01

Particle water (liquid water content, LWC) and aerosol pH are important parameters of the aerosol phase, affecting heterogeneous chemistry and bioavailability of nutrients that profoundly impact cloud formation, atmospheric composition, and atmospheric fluxes of nutrients to ecosystems. Few measurements of in situ LWC and pH, however, exist in the published literature. Using concurrent measurements of aerosol chemical composition, cloud condensation nuclei activity, and tandem light scattering coefficients, the particle water mass concentrations associated with the aerosol inorganic (Winorg) and organic (Worg) components are determined for measurements conducted at the Finokalia atmospheric observation station in the eastern Mediterranean between June and November 2012. These data are interpreted using the ISORROPIA-II thermodynamic model to predict the pH of aerosols originating from the various sources that influence air quality in the region. On average, closure between predicted aerosol water and that determined by comparison of ambient with dry light scattering coefficients was achieved to within 8 % (slope = 0.92, R2 = 0.8, n = 5201 points). Based on the scattering measurements, a parameterization is also derived, capable of reproducing the hygroscopic growth factor (f(RH)) within 15 % of the measured values. The highest aerosol water concentrations are observed during nighttime, when relative humidity is highest and the collapse of the boundary layer increases the aerosol concentration. A significant diurnal variability is found for Worg with morning and afternoon average mass concentrations being 10-15 times lower than nighttime concentrations, thus rendering Winorg the main form of particle water during daytime. The average value of total aerosol water was 2.19 ± 1.75 µg m-3, contributing on average up to 33 % of the total submicron mass concentration. Average aerosol water associated with organics, Worg, was equal to 0.56 ± 0.37 µg m-3; thus, organics contributed about 27.5 % to the total aerosol water, mostly during early morning, late evening, and nighttime hours.

The aerosol was found to be highly acidic with calculated aerosol pH varying from 0.5 to 2.8 throughout the study period. Biomass burning aerosol presented the highest values of pH in the submicron fraction and the lowest values in total water mass concentration. The low pH values observed in the submicron mode and independently of air mass origin could increase nutrient availability and especially P solubility, which is the nutrient limiting sea water productivity of the eastern Mediterranean.

Particle water and pH in the Eastern Mediterranean: sources variability and implications for nutrients availability

NASA Astrophysics Data System (ADS)

Nikolaou, P.; Bougiatioti, A.; Stavroulas, I.; Kouvarakis, G.; Nenes, A.; Weber, R.; Kanakidou, M.; Mihalopoulos, N.

2015-10-01

Particle water (LWC) and aerosol pH drive the aerosol phase, heterogeneous chemistry and bioavailability of nutrients that profoundly impact cloud formation, atmospheric composition and atmospheric fluxes of nutrients to ecosystems. Few measurements of in-situ LWC and pH however exist in the published literature. Using concurrent measurements of aerosol chemical composition, cloud condensation nuclei activity and tandem light scattering coefficients, the particle water mass concentrations associated with the aerosol inorganic (Winorg) and organic (Worg) components are determined for measurements conducted at the Finokalia atmospheric observation station in the eastern Mediterranean between August and November 2012. These data are interpreted using the ISORROPIA-II thermodynamic model to predict pH of aerosols originating from the various sources that influence air quality in the region. On average, closure between predicted aerosol water and that determined by comparison of ambient with dry light scattering coefficients was achieved to within 8 % (slope = 0.92, R2 = 0.8, n = 5201 points). Based on the scattering measurements a parameterization is also derived, capable of reproducing the hygroscopic growth factor (f(RH)) within 15 % of the measured values. The highest aerosol water concentrations are observed during nighttime, when relative humidity is highest and the collapse of the boundary layer increases the aerosol concentration. A significant diurnal variability is found for Worg with morning and afternoon average mass concentrations being 10-15 times lower than nighttime concentrations, thus rendering Winorg the main form of particle water during daytime. The average value of total aerosol water was 2.19 ± 1.75 μg m-3, contributing on average up to 33 % of the total submicron mass concentration. Average aerosol water associated with organics, Worg, was equal to 0.56 ± 0.37 μg m-3, thus organics contributed about 27.5 % to the total aerosol water, mostly during early morning, late evening and nighttime hours. The aerosol was found to be highly acidic with calculated aerosol pH varying from 0.5 to 2.8 throughout the study period. Biomass burning aerosol presented the highest values of pH in the submicron fraction and the lowest values in total water mass concentration. The low pH values observed in the submicron mode and independently of air masses origin could increase nutrient availability and especially P solubility, which is the nutrient limiting sea water productivity of the eastern Mediterranean.

WMI-2000

EPA Pesticide Factsheets

Technical product bulletin: this biological additive is used as a bioremediation agent in oil spill cleanups. It works in fresh or salt water, and at specified ranges of pH, temperature, oxygen, and nutrient availability (nitrogen and phosophorous).

Electrochemical control of pH in a hydroponic nutrient solution

NASA Technical Reports Server (NTRS)

Schwartzkopf, S. H.

1986-01-01

The electrochemical pH control system described was found to provide a feasible alternative method of controlling nutrient solution pH for CELSS applications. The plants grown in nutrient solution in which the pH was controlled electrochemically showed no adverse effects. Further research into the design of a larger capacity electrode bridge for better control is indicated by the results of this experiment, and is currently under way.

Soil Chemical Property Changes in Eggplant/Garlic Relay Intercropping Systems under Continuous Cropping

PubMed Central

Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen; Zhang, Mengru; Zhang, Hongjing

2014-01-01

Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercropping eggplant with garlic (Allium sativum L.) on soil enzyme activities, available nutrient contents, and pH value under a plastic tunnel. Three treatments were in triplicate using randomized block design: eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). The major results are as follows: (1) the activities of soil invertase, urease, and alkaline phosphatase were generally enhanced in NG and GG treatments; (2) relay intercropping significantly increased the soil available nutrient contents, and they were mostly higher in GG than NG. On April 11, 2011, the eggplant/garlic co-growth stage, the available nitrogen content in GG was 76.30 mg·kg−1, significantly higher than 61.95 mg·kg−1 in NG. For available potassium on April 17, 2012, they were 398.48 and 387.97 mg·kg−1 in NG and GG, both were significantly higher than 314.84 mg·kg−1 in CK; (3) the soil pH showed a significantly higher level in NG treatment, but lower in GG treatment compared with CK. For the last samples in 2012, soil pH in NG and GG were 7.70 and 7.46, the highest and lowest one among them; (4) the alkaline phosphatase activity and pH displayed a similar decreasing trend with continuous cropping. These findings indicate that relay intercropping eggplant with garlic could be an ideal farming system to effectively improve soil nutrient content, increase soil fertility, and alleviate soil sickness to some extent. These findings are important in helping to develop sustainable eggplant production. PMID:25340875

Soil chemical property changes in eggplant/garlic relay intercropping systems under continuous cropping.

PubMed

Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen; Zhang, Mengru; Zhang, Hongjing

2014-01-01

Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercropping eggplant with garlic (Allium sativum L.) on soil enzyme activities, available nutrient contents, and pH value under a plastic tunnel. Three treatments were in triplicate using randomized block design: eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). The major results are as follows: (1) the activities of soil invertase, urease, and alkaline phosphatase were generally enhanced in NG and GG treatments; (2) relay intercropping significantly increased the soil available nutrient contents, and they were mostly higher in GG than NG. On April 11, 2011, the eggplant/garlic co-growth stage, the available nitrogen content in GG was 76.30 mg·kg(-1), significantly higher than 61.95 mg·kg(-1) in NG. For available potassium on April 17, 2012, they were 398.48 and 387.97 mg·kg(-1) in NG and GG, both were significantly higher than 314.84 mg·kg(-1) in CK; (3) the soil pH showed a significantly higher level in NG treatment, but lower in GG treatment compared with CK. For the last samples in 2012, soil pH in NG and GG were 7.70 and 7.46, the highest and lowest one among them; (4) the alkaline phosphatase activity and pH displayed a similar decreasing trend with continuous cropping. These findings indicate that relay intercropping eggplant with garlic could be an ideal farming system to effectively improve soil nutrient content, increase soil fertility, and alleviate soil sickness to some extent. These findings are important in helping to develop sustainable eggplant production.

Phosphorus, zinc, and boron influence yield components in Earliglow strawberry

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

May, G.M.; Pritts, M.P.

1993-01-01

The main effects and interactions of soil-applied P, B, and Zn on yield and its components were examined in the field at two pH levels with Earliglow' strawberries (Fragaria ananassa Duch.). Applied nutrients had significant effects on several yield components, but responses depended on the levels of other nutrients or the soil pH. At a soil pH of 5.5, yield responded linearly to B and quadratically to P. At pH 6.5, P interacted with B and Zn. Fruit count per inflorescence was the yield component most strongly associated with yield, followed by individual fruit weight. However, these two yield componentsmore » responded differently to soil-applied nutrients. Foliar nutrient levels generally did not increase with the amount of applied nutrient, but often an applied nutrient had a strong effect on the level of another nutrient. Leaf nutrient levels were often correlated with fruit levels, but foliar and fruit levels at harvest were not related to reproductive performance. The study identifies some of the problems inherent in using foliar nutrient levels to predict a yield response and demonstrates how plant responses to single nutrients depend on soil chemistry and the presence of other nutrients.« less

pH homeostasis links the nutrient sensing PKA/TORC1/Sch9 ménage-à-trois to stress tolerance and longevity.

PubMed

Deprez, Marie-Anne; Eskes, Elja; Wilms, Tobias; Ludovico, Paula; Winderickx, Joris

2018-01-12

The plasma membrane H + -ATPase Pma1 and the vacuolar V-ATPase act in close harmony to tightly control pH homeostasis, which is essential for a vast number of physiological processes. As these main two regulators of pH are responsive to the nutritional status of the cell, it seems evident that pH homeostasis acts in conjunction with nutrient-induced signalling pathways. Indeed, both PKA and the TORC1-Sch9 axis influence the proton pumping activity of the V-ATPase and possibly also of Pma1. In addition, it recently became clear that the proton acts as a second messenger to signal glucose availability via the V-ATPase to PKA and TORC1-Sch9. Given the prominent role of nutrient signalling in longevity, it is not surprising that pH homeostasis has been linked to ageing and longevity as well. A first indication is provided by acetic acid, whose uptake by the cell induces toxicity and affects longevity. Secondly, vacuolar acidity has been linked to autophagic processes, including mitophagy. In agreement with this, a decline in vacuolar acidity was shown to induce mitochondrial dysfunction and shorten lifespan. In addition, the asymmetric inheritance of Pma1 has been associated with replicative ageing and this again links to repercussions on vacuolar pH. Taken together, accumulating evidence indicates that pH homeostasis plays a prominent role in the determination of ageing and longevity, thereby providing new perspectives and avenues to explore the underlying molecular mechanisms.

Unravelling the limits to tree height: a major role for water and nutrient trade-offs.

PubMed

Cramer, Michael D

2012-05-01

Competition for light has driven forest trees to grow exceedingly tall, but the lack of a single universal limit to tree height indicates multiple interacting environmental limitations. Because soil nutrient availability is determined by both nutrient concentrations and soil water, water and nutrient availabilities may interact in determining realised nutrient availability and consequently tree height. In SW Australia, which is characterised by nutrient impoverished soils that support some of the world's tallest forests, total [P] and water availability were independently correlated with tree height (r = 0.42 and 0.39, respectively). However, interactions between water availability and each of total [P], pH and [Mg] contributed to a multiple linear regression model of tree height (r = 0.72). A boosted regression tree model showed that maximum tree height was correlated with water availability (24%), followed by soil properties including total P (11%), Mg (10%) and total N (9%), amongst others, and that there was an interaction between water availability and total [P] in determining maximum tree height. These interactions indicated a trade-off between water and P availability in determining maximum tree height in SW Australia. This is enabled by a species assemblage capable of growing tall and surviving (some) disturbances. The mechanism for this trade-off is suggested to be through water enabling mass-flow and diffusive mobility of P, particularly of relatively mobile organic P, although water interactions with microbial activity could also play a role.

Effect of essential oil concentration on the pH of nutrient and Iso-sensitest broth.

PubMed

Hood, J R; Cavanagh, H M A; Wilkinson, J M

2004-11-01

The role of pH on the antimicrobial activity of essential oils has not been well studied. The effect of four essential oils: Backhousia citriodora, Melaleuca alternifolia, Lavandula angustifolia and Santalum spicatum (0.1% to 10%) on the pH of two commonly used media, nutrient broth and Iso-sensitest broth, was therefore undertaken. Small (less than 0.5 pH units) but statistically significant differences between the pH of the two media followed the addition of M. alternifolia, L. angustifolia and S. spicatum essential oil. In general the effect on pH was greatest at higher concentrations and the fall in pH was greatest in the nutrient broth. The addition of B. citriodora essential oil to nutrient broth resulted in a fall in pH from 7.29 +/- 0.02 (no oil) to 5.2 +/- 0.03 (10% oil). This effect was not observed in the Iso-sensitest broth. Copyright 2004 John Wiley & Sons, Ltd.

Sources of Nutrients to Nearshore Areas of a Eutrophic Estuary: Implications for Nutrient-Enhanced Acidification in Puget Sound

NASA Astrophysics Data System (ADS)

Pacella, S. R.

2016-02-01

Ocean acidification has recently been highlighted as a major stressor for coastal organisms. Further work is needed to assess the role of anthropogenic nutrient additions in eutrophied systems on local biological processes, and how this interacts with CO2 emission-driven acidification. This study sought to distinguish changes in pH caused by natural versus anthropogenically affected processes. We quantified the variability in water column pH attributable to primary production and respiration fueled by anthropogenically derived nitrogen in a shallow nearshore area. Two study sites were located in shallow subtidal areas of the Snohomish River estuary, a eutrophic system located in central Puget Sound, Washington. These sites were chosen due to the presence of heavy agricultural activity, urbanized areas with associated waste water treatment, as well as influence from deep, high CO2 marine waters transported through the Strait of Juan de Fuca and upwelled into the area during spring and summer. Data was collected from July-December 2015 utilizing continuous moorings and discrete water column sampling. Analysis of stable isotopes, δ15N, δ18O-NO3, δ15N-NH4, was used to estimate the relative contributions of anthropogenic versus upwelled marine nitrogen sources. Continuous monitoring of pH, dissolved oxygen, temperature, and salinity was conducted at both study sites to link changes in nutrient source and availability with changes in pH. We predicted that isotope data would indicate greater contributions of nitrogen from agriculture and wastewater rather than upwelling in the shallow, nearshore study sites. This study seeks to distinguish the relative magnitude of pH change stimulated by anthropogenic versus natural sources of nitrogen to inform public policy decisions in critically important nearshore ecosystems.

Nutrient limitation and morphological plasticity of the carnivorous pitcher plant Sarracenia purpurea in contrasting wetland environments.

PubMed

Bott, Terry; Meyer, Gretchen A; Young, Erica B

2008-01-01

* Plasticity of leaf nutrient content and morphology, and macronutrient limitation were examined in the northern pitcher plant, Sarracenia purpurea subsp. purpurea, in relation to soil nutrient availability in an open, neutral pH fen and a shady, acidic ombrotrophic bog, over 2 yr following reciprocal transplantation of S. purpurea between the wetlands. * In both wetlands, plants were limited by nitrogen (N) but not phosphorus (P) (N content < 2% DW(-1), N : P < 14) but photosynthetic quantum yields were high (F(V)/F(M) > 0.79). Despite carnivory, leaf N content correlated with dissolved N availability to plant roots (leaf N vs , r(2) = 0.344, P < 0.0001); carnivorous N acquisition did not apparently overcome N limitation. * Following transplantation, N content and leaf morphological traits changed in new leaves to become more similar to plants in the new environment, reflecting wetland nutrient availability. Changes in leaf morphology were faster when plants were transplanted from fen to bog than from bog to fen, possibly reflecting a more stressful environment in the bog. * Morphological plasticity observed in response to changes in nutrient supply to the roots in natural habitats complements previous observations of morphological changes with experimental nutrient addition to pitchers.

A six-year longitudinal study of phosphorus enrichment on soil enzymes in acidic forest soils.

NASA Astrophysics Data System (ADS)

Deforest, J. L.; Freedman, Z.

2017-12-01

Acidic nitrogen (N) deposition may be shifting the nutrient economies of forest soils from one dominated by N more towards phosphorus (P) limitation. While the short-term responses of nutrient enrichment experiments are reported, there is a lack of information on the longer-term response mediating ecosystem nutrient dynamics, especially for P. We hypothesized that long-term soil P amendments should result in the persistent suppression of P-acquiring extracellular enzymes when compared with ambient soils. Alternatively, vegetation and/or the microbial community may have acclimated to require more P (i.e., communities more suitable to the altered nutrient economy) resulting in an increase in the activity of P-acquiring enzymes relative to carbon (C) and N-acquiring enzyme activity. To test the hypothesis, P availability was indirectly and/or directly increased by raising soil pH and/or the addition of phosphate fertilizer and maintained for six years. Study sites were in two North American eastern deciduous forest regions on glaciated soils with modest P availability and unglaciated with low P availability. For the glaciated sites, C:N acquiring enzyme activity remained stable and was insensitive to 6 years of elevated pH and/or P in the, but there was modest increases in the unglaciated site. Phosphorus-acquiring enzyme activity was insensitive to the treatments in the glaciated sites. For unglaciated sites, P-acquiring enzyme activity was suppressed under P addition in year one, rebounded in the second year, and was suppressed in the subsequent years. These results suggest that the basal nutrient resources of an ecosystem will have a very strong influence on its response to nutrient enrichment. Likewise, the second-year recovery of P-acquiring enzyme activity might be evidence of acclimation, but the gradual yearly suppression of these enzymes suggests the system has not reach a steady state.

Effects of Low pH on Photosynthesis, Related Physiological Parameters, and Nutrient Profiles of Citrus

PubMed Central

Long, An; Zhang, Jiang; Yang, Lin-Tong; Ye, Xin; Lai, Ning-Wei; Tan, Ling-Ling; Lin, Dan; Chen, Li-Song

2017-01-01

Seedlings of “Xuegan” (Citrus sinensis) and “Sour pummelo” (Citrus grandis) were irrigated daily with a nutrient solution at a pH of 2.5, 3, 4, 5, or 6 for 9 months. Thereafter, the following responses were investigated: seedling growth; root, stem, and leaf concentrations of nutrient elements; leaf gas exchange, pigment concentration, ribulose-1,5-bisphosphate carboxylase/oxygenase activity and chlorophyll a fluorescence; relative water content, total soluble protein level, H2O2 production and electrolyte leakage in roots and leaves. This was done (a) to determine how low pH affects photosynthesis, related physiological parameters, and mineral nutrient profiles; and (b) to understand the mechanisms by which low pH may cause a decrease in leaf CO2 assimilation. The pH 2.5 greatly inhibited seedling growth, and many physiological parameters were altered only at pH 2.5; pH 3 slightly inhibited seedling growth; pH 4 had almost no influence on seedling growth; and seedling growth and many physiological parameters reached their maximum at pH 5. No seedlings died at any given pH. These results demonstrate that citrus survival is insensitive to low pH. H+-toxicity may directly damage citrus roots, thus affecting the uptake of mineral nutrients and water. H+-toxicity and a decreased uptake of nutrients (i.e., nitrogen, phosphorus, potassium, calcium, and magnesium) and water were likely responsible for the low pH-induced inhibition of growth. Leaf CO2 assimilation was inhibited only at pH 2.5. The combinations of an impaired photosynthetic electron transport chain, increased production of reactive oxygen species, and decreased uptake of nutrients and water might account for the pH 2.5-induced decrease in CO2 assimilation. Mottled bleached leaves only occurred in the pH 2.5-treated C. grandis seedlings. Furthermore, the pH 2.5-induced alterations of leaf CO2 assimilation, water-use efficiency, chlorophylls, polyphasic chlorophyll a fluorescence (OJIP) transients and many fluorescence parameters, root and leaf total soluble proteins, H2O2 production, and electrolyte leakage were all slightly greater in C. grandis than in C. sinensis seedlings. Hence, C. sinensis was slightly more tolerant to low pH than C. grandis. In conclusion, our findings provide novel insight into the causes of low pH-induced inhibition of seedling growth and leaf CO2 assimilation. PMID:28270819

Effects of Low pH on Photosynthesis, Related Physiological Parameters, and Nutrient Profiles of Citrus.

PubMed

Long, An; Zhang, Jiang; Yang, Lin-Tong; Ye, Xin; Lai, Ning-Wei; Tan, Ling-Ling; Lin, Dan; Chen, Li-Song

2017-01-01

Seedlings of "Xuegan" ( Citrus sinensis ) and "Sour pummelo" ( Citrus grandis ) were irrigated daily with a nutrient solution at a pH of 2.5, 3, 4, 5, or 6 for 9 months. Thereafter, the following responses were investigated: seedling growth; root, stem, and leaf concentrations of nutrient elements; leaf gas exchange, pigment concentration, ribulose-1,5-bisphosphate carboxylase/oxygenase activity and chlorophyll a fluorescence; relative water content, total soluble protein level, H 2 O 2 production and electrolyte leakage in roots and leaves. This was done ( a ) to determine how low pH affects photosynthesis, related physiological parameters, and mineral nutrient profiles; and ( b ) to understand the mechanisms by which low pH may cause a decrease in leaf CO 2 assimilation. The pH 2.5 greatly inhibited seedling growth, and many physiological parameters were altered only at pH 2.5; pH 3 slightly inhibited seedling growth; pH 4 had almost no influence on seedling growth; and seedling growth and many physiological parameters reached their maximum at pH 5. No seedlings died at any given pH. These results demonstrate that citrus survival is insensitive to low pH. H + -toxicity may directly damage citrus roots, thus affecting the uptake of mineral nutrients and water. H + -toxicity and a decreased uptake of nutrients (i.e., nitrogen, phosphorus, potassium, calcium, and magnesium) and water were likely responsible for the low pH-induced inhibition of growth. Leaf CO 2 assimilation was inhibited only at pH 2.5. The combinations of an impaired photosynthetic electron transport chain, increased production of reactive oxygen species, and decreased uptake of nutrients and water might account for the pH 2.5-induced decrease in CO 2 assimilation. Mottled bleached leaves only occurred in the pH 2.5-treated C. grandis seedlings. Furthermore, the pH 2.5-induced alterations of leaf CO 2 assimilation, water-use efficiency, chlorophylls, polyphasic chlorophyll a fluorescence (OJIP) transients and many fluorescence parameters, root and leaf total soluble proteins, H 2 O 2 production, and electrolyte leakage were all slightly greater in C. grandis than in C. sinensis seedlings. Hence, C. sinensis was slightly more tolerant to low pH than C. grandis . In conclusion, our findings provide novel insight into the causes of low pH-induced inhibition of seedling growth and leaf CO 2 assimilation.

The influence of soil pH and humus content on received by Mehlich 3 method nutrients analysis results

NASA Astrophysics Data System (ADS)

Tonutare, Tonu; Krebstein, Kadri; Rodima, Ako; Kõlli, Raimo; Künnapas, Allan; Rebane, Jaanus; Penu, Priit; Vennik, Kersti; Soobik, Liina

2015-04-01

Soils provide vital ecosystem functions, playing an important role in our economy and in healthy living environment. However, soils are increasingly degrading in Europe and at the global level. Knowledge about the content of major plant available nutrients, i.e. calcium, magnesium, potassium and phosphorus, plays an important role in the sustainable soil management. Mobility of nutrients depends directly on the environmental conditions, two of the most important factors are the pH and organic matter content. Therefore it is essential to have correct information about the content and behaviour of the above named elements in soil, both from the environmental and agronomical viewpoint. During the last decades several extracting solutions which are suitable for the evaluation of nutrient status of soils have been developed for this purpose. One of them is called Mehlich 3 which is widely used in USA, Canada and some European countries (e.g. Estonia, Czech Republic) because of its suitability to extract several major plant nutrients from the soil simultaneously. There are several different instrumental methods used for the analysis of nutrient elements in the soil extract. Potassium, magnesium and calcium are widely analysed by the AAS (atomic absorption spectroscopic) method or by the ICP (inductively coupled plasma) spectroscopic methods. Molecular spectroscopy and ICP spectroscopy were used for the phosphorus determination. In 2011 a new multielemental instrumental method MP-AES (microwave plasma atomic emission spectroscopy) was added to them. Due to its lower detection limits and multielemental character, compared with AAS, and lower exploitation costs, compared with ICP, the MP-AES has a good potential to achieve a leading position in soil nutrient analysis in the future. The objective of this study was to investigate: (i) the impact of soil pH and humus content and (ii) applicability of MP-AES instrumental method for the determination of soil nutrients extracted according to Mehlich 3. For the experiment 100 soil samples with different content of organic matter and pH were used. The determination of Ca, Mg, K and P was analysed by MP and ICP methods and additionally P was analysed molecular spectroscopically. Within the framework of the study the regressions between MP and ICP methods were created for all the analysed elements, i.e. Ca, Mg, K and P. According to MP and ICP, the relationships between the analysed soil major nutrient contents at different soil humus levels and at different pH ranges were determined for the evaluation of their impact. The optimal instrumental settings for calcium, magnesium and potassium analysis, according to Mehlich 3 using MP-AES method, are reported.

Organic wastes from bioenergy and ecological sanitation as a soil fertility improver: a field experiment in a tropical Andosol

NASA Astrophysics Data System (ADS)

Krause, Ariane; Nehls, Thomas; George, Eckhard; Kaupenjohann, Martin

2016-04-01

Andosols require the regular application of phosphorus (P) to sustain crop productivity. On an Andosol in NW Tanzania, we studied the short-term effects of amending standard compost, biogas slurry and CaSa compost (containing biochar and sanitized human excreta) on (i) the soil's physico-chemical properties, on (ii) biomass growth and crop productivity, and on (iii) the plants' nutrient status. The practice-oriented experiment design included the intercropping of seven locally grown crop species planted on 9 m2 plots with five repetitions arranged as a Latin rectangle. Differences in plant growth (biomass production and crop yield, e.g., of Zea mays) and crop nutrition (total C, N, P, K, Ca, Mg, Zn, etc.) were related to pH, CEC (cation exchange capacity), total C and the availability of nutrients (N, P, K, etc.) and water (water retention characteristics, bulk density, etc.) in the soil. None of the amendments had any significant effect on soil water availability, so the observed variations in crop yield and plant nutrition are attributed to nutrient availability. Applying CaSa compost increased the soil pH from 5.3 to 5.9 and the level of available P from 0.5 to 4.4 mg per kg. Compared to the control, adding biogas slurry, standard compost and CaSa compost increased the aboveground biomass of Zea mays by, respectively, 140, 154 and 211 %. The grain yields of maize on soil treated with biogas slurry, standard compost and CaSa compost were, respectively, 2.63, 3.18 and 4.40 t ha-1, compared to only 1.10 t ha-1 on unamended plots. All treatments enhanced crop productivity and increased the uptake of nutrients into the maize grains. The CaSa compost was most effective in mitigating P deficiency and soil acidification. We conclude that all treatments are viable as a substitute for synthetic fertilizers. Nevertheless, further steps are required to integrate the tested soil amendments into farm-scale nutrient management and to balance the additions and removals of nutrients, so that the cycle can be closed.

Fine particle water and pH in the Eastern Mediterranean: Sources, variability and implications for nutrients availability

NASA Astrophysics Data System (ADS)

Bougiatioti, Aikaterini; Nikolaou, Panayiota; Stavroulas, Iasonas; Kouvarakis, Giorgos; Nenes, Athanasios; Weber, Rodney; Kanakidou, Maria; Mihalopoulos, Nikolaos

2016-04-01

Atmospheric particles have the ability to absorb significant amounts of water, which greatly impacts on their physical and chemical properties. Direclty linked to aerosol pH and LWC is the bioavailability of nutrients contained within mineral dust, involving pH-dependent catalyzed redox-reaction pathways. Liquid water content (LWC) and pH, even though are important constituents of the aerosol phase, are rarely monitored. Direct measurements of aerosol pH "in situ" are scarce and require considerations owing to the non-conserved nature of the hydronium ion and partial dissociation of inorganic and organic electrolytes in the aerosol. To overcome these challenges, indirect alternatives such as measuring the semi-volatile partitioning of key species sensitive to pH, combined with comprehensive models are used to provide a reasonably accurate estimate of pH that can be carried out with routine measurements. Using concurrent measurements of aerosol chemical composition, tandem light scattering coefficients and the thermodynamic model ISORROPIA-II, LWC mass concentrations associated with the aerosol inorganic and organic components are determined for the remote background site of Finokalia, Crete. The predicted water was subsequently compared to the one measured by the ambient versus dry light scattering coefficients. The sum of Winorg and Worg was highly correlated and in close agreement with the measured LWC (on average within 10%), with slope 0.92 (R2=0.8) for the whole measurement period between August and November 2012 (n=5201 points). As expected, the highest fine aerosol water values are observed during night-time, when RH is at its maximum, resulting in important water uptake. The average concentration of total aerosol water was found to be 2.19±1.75 μg m-3, which according to the dry mass measurements, can contribute on average up to 33% to the total aerosol submicron mass. The average Worg was found to be 0.56±0.37 μg m-3, which constitutes about 28% of the total calculated water. Particle pH is also calculated with the help of ISORROPIA-II, and during the studied period, values varied from 0.5 to 2.8, indicating that the aerosol was highly acidic. pH values were also studied depending on the source/origin of the sampled air masses and biomass burning aerosol was found to exhibit the highest values of PM1 pH and the lowest values in total water mass concentrations. The two natural sources, namely mineral and marine origin, contained the largest amounts of total submicron water and the lowest contribution of organic water, as expected. The low pH values estimated for the studied period in the submicron mode and independently of the air masses' origin could potentially have important implications for nutrient availability, especially for phosphorus solubility, which is the nutrient limiting sea water productivity of the Eastern Mediterranean.

Coupling of soil respiration and nutrient mineralization: What is the role of land use?

NASA Astrophysics Data System (ADS)

Gan, Huei Ying; Schoening, Ingo; Schrumpf, Marion

2017-04-01

Microbial decomposition of soil organic matter (SOM) is coupling carbon (C) and nutrient mineralization. In order to meet their stoichiometric requirements for growth, it can be assumed that microbes have to mineralize (or remove) relative more organic carbon (OC) to acquire limiting nutrients at sites with large carbon-to-nutrient (C:N, C:P, C:S) ratios of SOM. Land use and management intensities are important controls for belowground C and nutrient availabilities, but their effect on the combined carbon and nutrient mineralization and carbon use efficiency (CUE) have rarely been addressed. The main objective of this study was to test the effect of land use (forest versus grassland), forest management (unmanaged beech forest and age-class managed coniferous and deciduous forests) and grassland management (fertilized and unfertilized meadow, mown pasture and pasture) on the stoichiometry of mineralized C, N, P and S. We incubated a total of 120 topsoil samples (0-10 cm) from three German study regions with different soil types for two weeks in microlysimeters and measured CO2 evolution and leachable organic carbon (DOC) and nutrients (NH4+, NO3-, SO42- and PO43-). The relationships between metabolic quotient (microbial respiration per unit microbial biomass; qCO2) and soil nutrient concentrations were compared between different land use and management. Preliminary results showed that qCO2 was significantly higher (p<0.001) in forests than grasslands. This supports our hypothesis that under higher nutrient limitations in forest, more energy may be allocated for maintenance than growth. In forest, qCO2 was strongly correlated to C:N ratio (r =0.84, p<0.001), while C:N was less strongly correlated with qCO2 in the grasslands (r =0.35, p>0.05). As C:N ratio was significantly higher (p<0.05) in forests (14.9±0.3) than grasslands (10.0±0.3), this finding agreed with previous studies that more C per unit microbial C is respired under lower N availability. Similary in forests, qCO2 was found to be strongly correlated to inorganic P (Olsen) content (r =0.82, p<0.001), whereas weaker correlation was observed in the grasslands (r =0.47, p>0.05). The stronger correlation in forests might indicate higher P limitation as compared to grasslands. Soil pH showed strong negative effect on qCO2 in the forests (r =-0.68, p<0.005) while positively correlated to qCO2 in the grasslands (r =0.42, p<0.05). This indicates that lower soil pH in forests results in higher qCO2 and lower CUE, but higher soil pH in the grasslands could also constrain microbial activities and result in lower CUE. Our first results suggest that qCO2 is affected by land use, and that this effect could be due to differences in nutrient availability. More analysis will follow to elucidate the interactions between qCO2 and other nutrients, and how is this affected by forest and grassland management.

Soil pH and electrical conductivity are key edaphic factors shaping bacterial communities of greenhouse soils in Korea.

PubMed

Kim, Jeong Myeong; Roh, An-Sung; Choi, Seung-Chul; Kim, Eun-Jeong; Choi, Moon-Tae; Ahn, Byung-Koo; Kim, Sun-Kuk; Lee, Young-Han; Joa, Jae-Ho; Kang, Seong-Soo; Lee, Shin Ae; Ahn, Jae-Hyung; Song, Jaekyeong; Weon, Hang-Yeon

2016-12-01

Soil microorganisms play an essential role in soil ecosystem processes such as organic matter decomposition, nutrient cycling, and plant nutrient availability. The land use for greenhouse cultivation has been increasing continuously, which involves an intensive input of agricultural materials to enhance productivity; however, relatively little is known about bacterial communities in greenhouse soils. To assess the effects of environmental factors on the soil bacterial diversity and community composition, a total of 187 greenhouse soil samples collected across Korea were subjected to bacterial 16S rRNA gene pyrosequencing analysis. A total of 11,865 operational taxonomic units at a 97% similarity cutoff level were detected from 847,560 sequences. Among nine soil factors evaluated; pH, electrical conductivity (EC), exchangeable cations (Ca 2+ , Mg 2+ , Na + , and K + ), available P 2 O 5 , organic matter, and NO 3 -N, soil pH was most strongly correlated with bacterial richness (polynomial regression, pH: R 2 = 0.1683, P < 0.001) and diversity (pH: R 2 = 0.1765, P < 0.001). Community dissimilarities (Bray-Curtis distance) were positively correlated with Euclidean distance for pH and EC (Mantel test, pH: r = 0.2672, P < 0.001; EC: r = 0.1473, P < 0.001). Among dominant phyla (> 1%), the relative abundances of Proteobacteria, Gemmatimonadetes, Acidobacteria, Bacteroidetes, Chloroflexi, and Planctomycetes were also more strongly correlated with pH and EC values, compared with other soil cation contents, such as Ca 2+ , Mg 2+ , Na + , and K + . Our results suggest that, despite the heterogeneity of various environmental variables, the bacterial communities of the intensively cultivated greenhouse soils were particularly influenced by soil pH and EC. These findings therefore shed light on the soil microbial ecology of greenhouse cultivation, which should be helpful for devising effective management strategies to enhance soil microbial diversity and improving crop productivity.

Influence of Acacia trees on soil nutrient levels in arid lands

NASA Astrophysics Data System (ADS)

De Boever, Maarten; Gabriels, Donald; Ouessar, Mohamed; Cornelis, Wim

2014-05-01

The potential of scattered trees as keystone structures in restoring degraded environments is gaining importance. Scattered trees have strong influence on their abiotic environment, mainly causing changes in microclimate, water budget and soil properties. They often function as 'nursing trees', facilitating the recruitment of other plants. Acacia raddiana is such a keystone species which persists on the edge of the Sahara desert. The study was conducted in a forest-steppe ecosystem in central Tunisia where several reforestation campaigns with Acacia took place. To indentify the impact of those trees on soil nutrients, changes in nutrient levels under scattered trees of three age stages were examined for the upper soil layer (0-10 cm) at five microsites with increasing distance from the trunk. In addition, changes in soil nutrient levels with depth underneath and outside the canopy were determined for the 0-30 cm soil layer. Higher concentrations of organic matter (OM) were found along the gradient from underneath to outside the canopy for large trees compared to medium and small trees, especially at microsites close to the trunk. Levels of soluble K, electrical conductivity (EC), available P, OM, total C and N decreased whereas pH and levels of soluble Mg increased with increasing distance from tree. Levels of soluble Ca and Na remained unchanged along the gradient. At the microsite closest to the trunk a significant decrease in levels of soluble K, EC, OM, available P, total C and N, while a significant increase in pH was found with increasing depth. The concentration of other nutrients remained unchanged or declined not differently underneath compared to outside the canopy with increasing depth. Differences in nutrient levels were largely driven by greater inputs of organic matter under trees. Hence, Acacia trees can affect the productivity and reproduction of understory species with the latter in term an important source of organic matter. This positive feedback mechanism is of crucial importance for soil nutrient conservation and the restoration of degraded arid environments.

Fertilization Shapes Bacterial Community Structure by Alteration of Soil pH.

PubMed

Zhang, Yuting; Shen, Hong; He, Xinhua; Thomas, Ben W; Lupwayi, Newton Z; Hao, Xiying; Thomas, Matthew C; Shi, Xiaojun

2017-01-01

Application of chemical fertilizer or manure can affect soil microorganisms directly by supplying nutrients and indirectly by altering soil pH. However, it remains uncertain which effect mostly shapes microbial community structure. We determined soil bacterial diversity and community structure by 454 pyrosequencing the V1-V3 regions of 16S rRNA genes after 7-years (2007-2014) of applying chemical nitrogen, phosphorus and potassium (NPK) fertilizers, composted manure or their combination to acidic (pH 5.8), near-neutral (pH 6.8) or alkaline (pH 8.4) Eutric Regosol soil in a maize-vegetable rotation in southwest China. In alkaline soil, nutrient sources did not affect bacterial Operational Taxonomic Unit (OTU) richness or Shannon diversity index, despite higher available N, P, K, and soil organic carbon in fertilized than in unfertilized soil. In contrast, bacterial OTU richness and Shannon diversity index were significantly lower in acidic and near-neutral soils under NPK than under manure or their combination, which corresponded with changes in soil pH. Permutational multivariate analysis of variance showed that bacterial community structure was significantly affected across these three soils, but the PCoA ordination patterns indicated the effect was less distinct among nutrient sources in alkaline than in acidic and near-neural soils. Distance-based redundancy analysis showed that bacterial community structures were significantly altered by soil pH in acidic and near-neutral soils, but not by any soil chemical properties in alkaline soil. The relative abundance (%) of most bacterial phyla was higher in near-neutral than in acidic or alkaline soils. The most dominant phyla were Proteobacteria (24.6%), Actinobacteria (19.7%), Chloroflexi (15.3%) and Acidobacteria (12.6%); the medium dominant phyla were Bacterioidetes (5.3%), Planctomycetes (4.8%), Gemmatimonadetes (4.5%), Firmicutes (3.4%), Cyanobacteria (2.1%), Nitrospirae (1.8%), and candidate division TM7 (1.0%); the least abundant phyla were Verrucomicrobia (0.7%), Armatimonadetes (0.6%), candidate division WS3 (0.4%) and Fibrobacteres (0.3%). In addition, Cyanobacteria and candidate division TM7 were more abundant in acidic soil, whereas Gemmatimonadetes, Nitrospirae and candidate division WS3 were more abundant in alkaline soil. We conclude that after 7-years of fertilization, soil bacterial diversity and community structure were shaped more by changes in soil pH rather than the direct effect of nutrient addition.

Changes in Forest Soil Properties in Different Successional Stages in Lower Tropical China

PubMed Central

Li, Yuelin; Yang, Fangfang; Ou, Yangxu; Zhang, Deqiang; Liu, Juxiu; Chu, Guowei; Zhang, Yaru; Otieno, Dennis; Zhou, Guoyi

2013-01-01

Background Natural forest succession often affects soil physical and chemical properties. Selected physical and chemical soil properties were studied in an old-growth forest across a forest successional series in Dinghushan Nature Reserve, Southern China. Methodology/Principal Findings The aim was to assess the effects of forest succession change on soil properties. Soil samples (0–20 cm depth) were collected from three forest types at different succession stages, namely pine (Pinus massoniana) forest (PMF), mixed pine and broadleaf forest (PBMF) and monsoon evergreen broadleaf forest (MEBF), representing early, middle and advanced successional stages respectively. The soil samples were analyzed for soil water storage (SWS), soil organic matter (SOM), soil microbial biomass carbon (SMBC), pH, NH4 +-N, available potassium (K), available phosphorus (P) and microelements (available copper (Cu), available zinc (Zn), available iron (Fe) and available boron (B)) between 1999 and 2009. The results showed that SWS, SOM, SMBC, Cu, Zn, Fe and B concentrations were higher in the advanced successional stage (MEBF stage). Conversely, P and pH were lower in the MEBF but higher in the PMF (early successional stage). pH, NH4 +-N, P and K declined while SOM, Zn, Cu, Fe and B increased with increasing forest age. Soil pH was lower than 4.5 in the three forest types, indicating that the surface soil was acidic, a stable trend in Dinghushan. Conclusion/Significance These findings demonstrated significant impacts of natural succession in an old-growth forest on the surface soil nutrient properties and organic matter. Changes in soil properties along the forest succession gradient may be a useful index for evaluating the successional stages of the subtropical forests. We caution that our inferences are drawn from a pseudo-replicated chronosequence, as true replicates were difficult to find. Further studies are needed to draw rigorous conclusions regarding on nutrient dynamics in different successional stages of forest. PMID:24244738

Soil Nutrient Assessment for Urban Ecosystems in Hubei, China

PubMed Central

Li, Zhi-guo; Zhang, Guo-shi; Liu, Yi; Wan, Kai-yuan; Zhang, Run-hua; Chen, Fang

2013-01-01

Recent urban landscape vegetation surveys conducted in many cities in China identified numerous plant nutrient deficiencies, especially in newly developed cities. Soil nutrients and soil nutrient management in the cities of Hubei province have not received adequate attention to date. The aims of this study were to characterize the available nutrients of urban soils from nine cities in Hubei province, China, and to assess how soil nutrient status is related to land use type and topography. Soil nutrients were measured in 405 sites from 1,215 soil samples collected from four land use types (park, institutional [including government building grounds, municipal party grounds, university grounds, and garden city institutes], residential, and roadside verges) and three topographies (mountainous [142–425 m a.s.l], hilly [66–112 m a.s.l], and plain [26–30 m a.s.l]). Chemical analyses showed that urban soils in Hubei had high pH and lower soil organic matter, available nitrogen (N), available phosphorus (P), and available boron (B) concentrations than natural soils. Nutrient concentrations were significantly different among land use types, with the roadside and residential areas having greater concentrations of calcium (Ca), sulfur (S), copper (Cu), manganese (Mn), and zinc (Zn) that were not deficient against the recommended ranges. Topographic comparisons showed statistically significant effects for 8 of the 11 chemical variables (p < 0.05). Concentrations of N, Ca, Mg, S, Cu, and Mn in plain cities were greater than those in mountainous cities and show a negative correlation with city elevation. These results provide data on urban soils characteristics in land use types and topography, and deliver significant information for city planners and policy makers. PMID:24086647

Soil nutrient assessment for urban ecosystems in Hubei, China.

PubMed

Li, Zhi-Guo; Zhang, Guo-Shi; Liu, Yi; Wan, Kai-Yuan; Zhang, Run-Hua; Chen, Fang

2013-01-01

Recent urban landscape vegetation surveys conducted in many cities in China identified numerous plant nutrient deficiencies, especially in newly developed cities. Soil nutrients and soil nutrient management in the cities of Hubei province have not received adequate attention to date. The aims of this study were to characterize the available nutrients of urban soils from nine cities in Hubei province, China, and to assess how soil nutrient status is related to land use type and topography. Soil nutrients were measured in 405 sites from 1,215 soil samples collected from four land use types (park, institutional [including government building grounds, municipal party grounds, university grounds, and garden city institutes], residential, and roadside verges) and three topographies (mountainous [142-425 m a.s.l], hilly [66-112 m a.s.l], and plain [26-30 m a.s.l]). Chemical analyses showed that urban soils in Hubei had high pH and lower soil organic matter, available nitrogen (N), available phosphorus (P), and available boron (B) concentrations than natural soils. Nutrient concentrations were significantly different among land use types, with the roadside and residential areas having greater concentrations of calcium (Ca), sulfur (S), copper (Cu), manganese (Mn), and zinc (Zn) that were not deficient against the recommended ranges. Topographic comparisons showed statistically significant effects for 8 of the 11 chemical variables (p < 0.05). Concentrations of N, Ca, Mg, S, Cu, and Mn in plain cities were greater than those in mountainous cities and show a negative correlation with city elevation. These results provide data on urban soils characteristics in land use types and topography, and deliver significant information for city planners and policy makers.

Comparison of the nutrient content of fresh fruit juices vs commercial fruit juices.

PubMed

Densupsoontorn, Narumon; Jirapinyo, Pipop; Thamonsiri, Nuchnoi; Wongarn, Renu; Phosuya, Panarat; Tritiprat, Amornrat; Patraarat, Siriphan; Pidatcha, Pannee; Suwannthol, Lerson

2002-08-01

To compare the types and quantities of carbohydrate, electrolytes, pH and osmolarity of fresh fruit juices and commercial fruit juices. Forty kinds of fresh fruits available in Thai markets were analyzed for types and quantities of carbohydrate, electrolyte, pH and osmolarity and compared with previously obtained data for commercial fruit juices. Most fresh fruit juices did not contain sucrose, whereas, commercial fruit juices mostly have sucrose in the range of 3-112 g/L. Although both fruit juices were acidic (pH varied from 3.6-6.7 and 3.2-5.8 of fresh juice and commercial juice), fresh fruit juices had a more neutral pH than commercial fruit juices. Apple, guava, orange, pear, and pineapple juices from commercial fruit juices had a high osmolarity compared with fresh fruit juices. All types of fresh fruit juices contained less sodium than commercial ones, whereas, most fresh fruit juices contained more potassium, phosphorus, and magnesium than commercial fluids. The nutrient content of fresh fruit juices and commercial fruit juices from the same kinds of fruits are not the same, possibly due to the manufacturing process. Therefore, physicians should know the composition of fruit juices in order to advise patients properly.

Oxygen and diverse nutrients influence the water kefir fermentation process.

PubMed

Laureys, David; Aerts, Maarten; Vandamme, Peter; De Vuyst, Luc

2018-08-01

Eight water kefir fermentation series differing in the presence of oxygen, the nutrient concentration, and the nutrient source were studied during eight consecutive backslopping steps. The presence of oxygen allowed the proliferation of acetic acid bacteria, resulting in high concentrations of acetic acid, and decreased the relative abundance of Bifidobacterium aquikefiri. Low nutrient concentrations resulted in slow water kefir fermentation and high pH values, which allowed the growth of Comamonas testosteroni/thiooxydans. Further, low nutrient concentrations favored the growth of Lactobacillus hilgardii and Dekkera bruxellensis, whereas high nutrient concentrations favored the growth of Lactobacillus nagelii and Saccharomyces cerevisiae. Dried figs, dried apricots, and raisins resulted in stable water kefir fermentation. Water kefir fermentation with dried apricots resulted in the highest pH and water kefir grain growth, whereas that with raisins resulted in the lowest pH and water kefir grain growth. Further, water kefir fermentation with raisins resembled fermentations with low nutrient concentrations, that with dried apricots resembled fermentations with normal nutrient concentrations, and that with fresh figs or a mixture of yeast extract and peptone resembled fermentations with high nutrient concentrations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Soil pH determines microbial diversity and composition in the park grass experiment.

PubMed

Zhalnina, Kateryna; Dias, Raquel; de Quadros, Patricia Dörr; Davis-Richardson, Austin; Camargo, Flavio A O; Clark, Ian M; McGrath, Steve P; Hirsch, Penny R; Triplett, Eric W

2015-02-01

The Park Grass experiment (PGE) in the UK has been ongoing since 1856. Its purpose is to study the response of biological communities to the long-term treatments and associated changes in soil parameters, particularly soil pH. In this study, soil samples were collected across pH gradient (pH 3.6-7) and a range of fertilizers (nitrogen as ammonium sulfate, nitrogen as sodium nitrate, phosphorous) to evaluate the effects nutrients have on soil parameters and microbial community structure. Illumina 16S ribosomal RNA (rRNA) amplicon sequencing was used to determine the relative abundances and diversity of bacterial and archaeal taxa. Relationships between treatments, measured soil parameters, and microbial communities were evaluated. Clostridium, Bacteroides, Bradyrhizobium, Mycobacterium, Ruminococcus, Paenibacillus, and Rhodoplanes were the most abundant genera found at the PGE. The main soil parameter that determined microbial composition, diversity, and biomass in the PGE soil was pH. The most probable mechanism of the pH impact on microbial community may include mediation of nutrient availability in the soil. Addition of nitrogen to the PGE plots as ammonium sulfate decreases soil pH through increased nitrification, which causes buildup of soil carbon, and hence increases C/N ratio. Plant species richness and plant productivity did not reveal significant relationships with microbial diversity; however, plant species richness was positively correlated with soil microbial biomass. Plants responded to the nitrogen treatments with an increase in productivity and a decrease in the species richness.

Assessment of Eutrophication in the Lower Yakima River Basin, Washington, 2004-07

USGS Publications Warehouse

Wise, Daniel R.; Zuroske, Marie L.; Carpenter, Kurt D.; Kiesling, Richard L.

2009-01-01

In response to concerns that excessive plant growth in the lower Yakima River in south-central Washington was degrading water quality and affecting recreational use, the U.S. Geological Survey and the South Yakima Conservation District conducted an assessment of eutrophication in the lower 116 miles of the river during the 2004-07 irrigation seasons (March - October). The lower Yakima River was divided into three distinct reaches based on geomorphology, habitat, aquatic plant and water-quality conditions. The Zillah reach extended from the upstream edge of the study area at river mile (RM) 116 to RM 72, and had abundant periphyton growth and sparse macrophyte growth, the lowest nutrient concentrations, and moderately severe summer dissolved oxygen and pH conditions in 2005. The Mabton reach extended from RM 72 to RM 47, and had sparse periphyton and macrophyte growth, the highest nutrient conditions, but the least severe summer dissolved oxygen and pH conditions in 2005. The Kiona reach extended from RM 47 to RM 4, and had abundant macrophyte and epiphytic algae growth, relatively high nutrient concentrations, and the most severe summer dissolved oxygen and pH conditions in 2005. Nutrient concentrations in the lower Yakima River were high enough at certain times and locations during the irrigation seasons during 2004-07 to support the abundant growth of periphytic algae and macrophytes. The metabolism associated with this aquatic plant growth caused large daily fluctuations in dissolved oxygen concentrations and pH levels that exceeded the Washington State water-quality standards for these parameters between July and September during all 4 years, but also during other months when streamflow was unusually low. The daily minimum dissolved oxygen concentration was strongly and negatively related to the preceding day's maximum water temperature - information that could prove useful if a dissolved oxygen predictive model is developed for the lower Yakima River. Periphytic algal growth generally was not nutrient-limited and frequently reached nuisance levels in the Zillah reach, where some surface-water nutrient concentrations were below the reference concentrations suggested by the U.S. Environmental Protection Agency. Although lowering nutrient concentrations in this reach might limit periphytic algal growth enough to improve dissolved oxygen and pH conditions, ground water inflow at some locations might still provide an adequate supply of nutrients for periphytic algal growth. Macrophyte growth in the Kiona reach was dominated by water stargrass (Heteranthera dubia), was far greater compared to the other two reaches, varied greatly between years, and was negatively related to greater spring runoff due to lower light availability. Lowering nutrient concentrations in the Kiona reach might not impact the level of macrophyte growth because macrophytes with extensive root systems such as water stargrass can get nutrients from river sediment. In addition, the results from this study did not indicate any nutrient uptake by the macrophytes from the water column (nutrient uptake from the sediment was not examined). Creating the prolonged turbid and deep conditions during spring necessary to suppress macrophyte growth in this reach would not be possible in years with low streamflow. In addition, because of the relatively stable substrate present in much of this reach, the macrophyte root systems would likely not be disturbed under all but the most extremely high streamflows that occur in the lower Yakima River.

Evaluation of H3A for determination of plant available P vs. FeAIO strips

USDA-ARS?s Scientific Manuscript database

Phosphorus is an essential nutrient for plant growth but in excess is a source of environmental pollution. Fertilizer additions of P are recommended based on soil tests; however, the commonly applied P extractants are often applied outside of their design criteria (specifically soil pH). As a resu...

Land reclamation with trees in Iowa

Treesearch

Richard B. Hall

1980-01-01

The most important considerations in revegetating reclaimed lands are soil pH, moisture availability, and the restoration of fertility and good nutrient cycling. Green ash, cottonwood, alder, Arnot bristly locust, and several conifers are used most in plantings. Emphasis is placed on the use of symbiotic nitrogen fixation and mycorrhizae to improve establishment and...

Numerical modelling of biophysicochemical effects on multispecies reactive transport in porous media involving Pseudomonas putida for potential microbial enhanced oil recovery application.

PubMed

Sivasankar, P; Rajesh Kanna, A; Suresh Kumar, G; Gummadi, Sathyanarayana N

2016-07-01

pH and resident time of injected slug plays a critical role in characterizing the reservoir for potential microbial enhanced oil recovery (MEOR) application. To investigate MEOR processes, a multispecies (microbes-nutrients) reactive transport model in porous media was developed by coupling kinetic and transport model. The present work differs from earlier works by explicitly determining parametric values required for kinetic model by experimental investigations using Pseudomonas putida at different pH conditions and subsequently performing sensitivity analysis of pH, resident time and water saturation on concentrations of microbes, nutrients and biosurfactant within reservoir. The results suggest that nutrient utilization and biosurfactant production are found to be maximum at pH 8 and 7.5 respectively. It is also found that the sucrose and biosurfactant concentrations are highly sensitive to pH rather than reservoir microbial concentration, while at larger resident time and water saturation, the microbial and nutrient concentrations were lesser due to enhanced dispersion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biochar and manure affect calcareous soil and corn silage nutrient concentrations and uptake.

PubMed

Lentz, R D; Ippolito, J A

2012-01-01

Carbon-rich biochar derived from the pyrolysis of biomass can sequester atmospheric CO, mitigate climate change, and potentially increase crop productivity. However, research is needed to confirm the suitability and sustainability of biochar application to different soils. To an irrigated calcareous soil, we applied stockpiled dairy manure (42 Mg ha dry wt) and hardwood-derived biochar (22.4 Mg ha), singly and in combination with manure, along with a control, yielding four treatments. Nitrogen fertilizer was applied when needed (based on preseason soil test N and crop requirements) in all plots and years, with N mineralized from added manure included in this determination. Available soil nutrients (NH-N; NO-N; Olsen P; and diethylenetriaminepentaacetic acid-extractable K, Mg, Na, Cu, Mn, Zn, and Fe), total C (TC), total N (TN), total organic C (TOC), and pH were evaluated annually, and silage corn nutrient concentration, yield, and uptake were measured over two growing seasons. Biochar treatment resulted in a 1.5-fold increase in available soil Mn and a 1.4-fold increase in TC and TOC, whereas manure produced a 1.2- to 1.7-fold increase in available nutrients (except Fe), compared with controls. In 2009 biochar increased corn silage B concentration but produced no yield increase; in 2010 biochar decreased corn silage TN (33%), S (7%) concentrations, and yield (36%) relative to controls. Manure produced a 1.3-fold increase in corn silage Cu, Mn, S, Mg, K, and TN concentrations and yield compared with the control in 2010. The combined biochar-manure effects were not synergistic except in the case of available soil Mn. In these calcareous soils, biochar did not alter pH or availability of P and cations, as is typically observed for acidic soils. If the second year results are representative, they suggest that biochar applications to calcareous soils may lead to reduced N availability, requiring additional soil N inputs to maintain yield targets. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

A Combined Model To Predict the Functionality of the Bacteriocin-Producing Lactobacillus sakei Strain CTC 494

PubMed Central

Leroy, Frédéric; De Vuyst, Luc

2003-01-01

The use of bacteriocin-producing lactic acid bacteria for improved food fermentation processes seems promising. However, lack of fundamental knowledge about the functionality of bacteriocin-producing strains under food fermentation conditions hampers their industrial use. Predictive microbiology or a mathematical estimation of microbial behavior in food ecosystems may help to overcome this problem. In this study, a combined model was developed that was able to estimate, from a given initial situation of temperature, pH, and nutrient availability, the growth and self-inhibition dynamics of a bacteriocin-producing Lactobacillus sakei CTC 494 culture in (modified) MRS broth. Moreover, the drop in pH induced by lactic acid production and the bacteriocin activity toward Listeria as an indicator organism were modeled. Self-inhibition was due to the depletion of nutrients as well as to the production of lactic acid. Lactic acid production resulted in a pH drop, an accumulation of toxic undissociated lactic acid molecules, and a shift in the dissociation degree of the growth-inhibiting buffer components. The model was validated experimentally. PMID:12571034

Nutrient pollution disrupts key ecosystem functions on coral reefs.

PubMed

Silbiger, Nyssa J; Nelson, Craig E; Remple, Kristina; Sevilla, Jessica K; Quinlan, Zachary A; Putnam, Hollie M; Fox, Michael D; Donahue, Megan J

2018-06-13

There is a long history of examining the impacts of nutrient pollution and pH on coral reefs. However, little is known about how these two stressors interact and influence coral reef ecosystem functioning. Using a six-week nutrient addition experiment, we measured the impact of elevated nitrate (NO - 3 ) and phosphate (PO 3- 4 ) on net community calcification (NCC) and net community production (NCP) rates of individual taxa and combined reef communities. Our study had four major outcomes: (i) NCC rates declined in response to nutrient addition in all substrate types, (ii) the mixed community switched from net calcification to net dissolution under medium and high nutrient conditions, (iii) nutrients augmented pH variability through modified photosynthesis and respiration rates, and (iv) nutrients disrupted the relationship between NCC and aragonite saturation state documented in ambient conditions. These results indicate that the negative effect of NO - 3 and PO 3- 4 addition on reef calcification is likely both a direct physiological response to nutrients and also an indirect response to a shifting pH environment from altered NCP rates. Here, we show that nutrient pollution could make reefs more vulnerable to global changes associated with ocean acidification and accelerate the predicted shift from net accretion to net erosion. © 2018 The Author(s).

Controlled environment crop production - Hydroponic vs. lunar regolith

NASA Technical Reports Server (NTRS)

Bugbee, Bruce G.; Salisbury, Frank B.

1989-01-01

The potential of controlled environment crop production in a lunar colony is discussed. Findings on the effects of optimal root-zone and aerial environments derived as part of the NASA CELSS project at Utah State are presented. The concept of growing wheat in optimal environment is discussed. It is suggested that genetic engineering might produce the ideal wheat cultivar for CELSS (about 100 mm in height with fewer leaves). The Utah State University hydroponic system is outlined and diagrams of the system and plant container construction are provided. Ratio of plant mass to solution mass, minimum root-zone volume, maintenance, and pH control are discussed. A comparison of liquid hydrophonic systems and lunar regoliths as substrates for plant growth is provided. The physiological processes that are affected by the root-zone environment are discussed including carbon partitioning, nutrient availability, nutrient absorption zones, root-zone oxygen, plant water potential, root-produced hormones, and rhizosphere pH control.

[Nutrient contents and microbial populations of aeolian sandy soil in Sanjiangyuan region of Qinghai Province].

PubMed

Lin, Chao-feng; Chen, Zhan-quan; Xue, Quan-hong; Lai, Hang-xian; Chen, Lai-sheng; Zhang, Deng-shan

2007-01-01

Sanjiangyuan region (the headstream of three rivers) in Qinghai Province of China is the highest and largest inland alpine wetland in the world. The study on the nutrient contents and microbial populations of aeolian sandy soils in this region showed that soil organic matter content increased with the evolution of aeolian sand dunes from un-stabilized to stabilized state, being 5.9 and 3.8 times higher in stabilized sand dune than in mobile and semi-stabilized sand dunes, respectively. Soil nitrogen and phosphorus contents increased in line with the amount of organic matter, while potassium content and pH value varied slightly. The microbial populations changed markedly with the development of vegetation, fixing of mobile sand, and increase of soil nutrients. The quantities of soil bacteria, fungi and actinomycetes were 4.0 and 2.8 times, 19.6 and 6.3 times, and 12.4 and 2.6 times higher in stabilized and semi-stabilized sand dunes than in mobile sand dune, respectively, indicating that soil microbial bio-diversity was increased with the evolution of aeolian sand dunes from mobile to stabilized state. In addition, the quantities of soil microbes were closely correlated with the contents of soil organic matter, total nitrogen, and available nitrogen and phosphorus, but not correlated with soil total phosphorus, total and available potassium, or pH value.

Assessment of factors limiting algal growth in acidic pit lakes--a case study from Western Australia, Australia.

PubMed

Kumar, R Naresh; McCullough, Clint D; Lund, Mark A; Larranaga, Santiago A

2016-03-01

Open-cut mining operations can form pit lakes on mine closure. These new water bodies typically have low nutrient concentrations and may have acidic and metal-contaminated waters from acid mine drainage (AMD) causing low algal biomass and algal biodiversity. A preliminary study was carried out on an acidic coal pit lake, Lake Kepwari, in Western Australia to determine which factors limited algal biomass. Water quality was monitored to obtain baseline data. pH ranged between 3.7 and 4.1, and solute concentrations were slightly elevated to levels of brackish water. Concentrations of N were highly relative to natural lakes, although concentrations of FRP (<0.01 mg/L) and C (total C 0.7-3.7 and DOC 0.7-3.5 mg/L) were very low, and as a result, algal growth was also extremely low. Microcosm experiment was conducted to test the hypothesis that nutrient enrichment will be able to stimulate algal growth regardless of water quality. Microcosms of Lake Kepwari water were amended with N, P and C nutrients with and without sediment. Nutrient amendments under microcosm conditions could not show any significant phytoplankton growth but was able to promote benthic algal growth. P amendments without sediment showed a statistically higher mean algal biomass concentration than controls or microcosms amended with phosphorus but with sediment did. Results indicated that algal biomass in acidic pit lake (Lake Kepwari) may be limited primarily by low nutrient concentrations (especially phosphorus) and not by low pH or elevated metal concentrations. Furthermore, sediment processes may also reduce the nutrient availability.

Advancing Analysis of Spatio-Temporal Variations of Soil Nutrients in the Water Level Fluctuation Zone of China’s Three Gorges Reservoir Using Self-Organizing Map

PubMed Central

Ye, Chen; Li, Siyue; Yang, Yuyi; Shu, Xiao; Zhang, Jiaquan; Zhang, Quanfa

2015-01-01

The ~350 km2 water level fluctuation zone (WLFZ) in the Three Gorges Reservoir (TGR) of China, situated at the intersection of terrestrial and aquatic ecosystems, experiences a great hydrological change with prolonged winter inundation. Soil samples were collected in 12 sites pre- (September 2008) and post submergence (June 2009) in the WLFZ and analyzed for soil nutrients. Self-organizing map (SOM) and statistical analysis including multi-way ANOVA, paired-T test, and stepwise least squares multiple regression were employed to determine the spatio-temporal variations of soil nutrients in relation to submergence, and their correlations with soil physical characteristics. Results showed significant spatial variability in nutrients along ~600 km long shoreline of the TGR before and after submergence. There were higher contents of organic matter, total nitrogen (TN), and nitrate (NO3-) in the lower reach and total phosphorus (TP) in the upper reach that were primarily due to the spatial variations in soil particle size composition and anthropogenic activities. Submergence enhanced soil available potassium (K), while significantly decreased soil N, possibly due to the alterations of soil particle size composition and increase in soil pH. In addition, SOM analysis determined important roles of soil pH value, bulk density, soil particle size (i.e., silt and sand) and nutrients (TP, TK, and AK) on the spatial and temporal variations in soil quality. Our results suggest that urban sewage and agricultural runoffs are primary pollutants that affect soil nutrients in the WLFZ of TGR. PMID:25789612

An evaluation of MES (2(N-Morpholino)ethanesulfonic acid) and Amberlite IRC-50 as pH buffers for nutrient solution studies

NASA Technical Reports Server (NTRS)

Bugbee, B. G.; Salisbury, F. B.

1985-01-01

All buffering agents used to stabilize pH in hydroponic research have disadvantages. Inorganic buffers are absorbed and may become phytotoxic. Solid carbonate salts temporarily mitigate decreasing pH but provide almost no protection against increasing pH, and they alter nutrient absorption. Exchange resins are more effective, but we find that they remove magnesium and manganese from solution. We have tested 2(N-Morpholino)ethanesulfonic acid (MES) as a buffering agent at concentrations of 1 and 10 mol m-3 (1 and 10 mM) with beans, corn, lettuce, tomatoes, and wheat. MES appears to be biologically inert and does not interact significantly with other solution ions. Relative growth rates among controls and MES treatments were nearly identical for each species during the trial period. The pH was stabilized by 1 mol m-3 MES. This buffer warrants further consideration in nutrient research.

[Correlation analysis of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata].

PubMed

Wu, Dan; Luo, Shi-qiong; Yang, Zhan-nan; Ma, Jing; Hong, Liang

2015-04-01

The relationship of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata were investigated by measuring nutrients, enzyme activity, pH, concentrations of microbe phospholipid fatty acids (PLFAs) in soils, and determining concentrations of polyphenols and total flavonoids of H. cordata. The research is aimed to understand characteristics of the planting soils and improve the quality of cultivated H. cordata. The soils at different sample sites varied greatly in nutrients, enzyme activity, pH, microbic PLFAs and polyphenols and all flavonoids. The content of total PLFAs in sample sites was following: bacteria > fungi > actinomyces > nematode. The content of bacteria PLFAs was 37.5%-65.0% at different sample sites. Activities of polyphenol oxidease, concentrations of available P and content of PLFAs of bacteria, actinomyces and total microorganisms in soils were significantly and positively related to the concentrations of polyphenols and total flavonoids of H. cordata, respectively (P < 0.05) . The Content of fungi PLFAs in soils was significantly and negatively related to concentrations of polyphenols and total flavonoids of H. cordata, respectively (P < 0.05). This study provides evidence that effectiveness of the soil nutrient, which may be improved due to transformation of soil microorganisms and enzymes to N and P in the soils, was beneficial to adaptation of H. cordata adapted to different soil conditions, and significantly affects metabolic accumulation of polyphenols and flavonoids of H. cordata.

Vermiculite's strong buffer capacity renders it unsuitable for studies of acidity on soybean (Glycine max L.) nodulation and growth.

PubMed

Indrasumunar, Arief; Gresshoff, Peter M

2013-11-14

Vermiculite is the most common soil-free growing substrate used for plants in horticultural and scientific studies due to its high water holding capacity. However, some studies are not suitable to be conducted in it. The described experiments aimed to test the suitability of vermiculite to study the effect of acidity on nodulation and growth of soybean (Glycine max L.). Two different nutrient solutions (Broughton & Dilworth, and modified Herridge nutrient solutions) with or without MES buffer addition were used to irrigate soybean grown on vermiculite growth substrates. The pH of nutrient solutions was adjusted to either pH 4.0 or 7.0 prior its use. The nodulation and vegetative growth of soybean plants were assessed at 3 and 4 weeks after inoculation. The unsuitability of presumably inert vermiculite as a physical plant growth substrate for studying the effects of acidity on soybean nodulation and plant growth was illustrated. Nodulation and growth of soybean grown in vermiculite were not affected by irrigation with pH-adjusted nutrient solution either at pH 4.0 or 7.0. This was reasonably caused by the ability of vermiculite to neutralise (buffer) the pH of the supplied nutrient solution (pH 2.0-7.0). Due to its buffering capacity, vermiculite cannot be used as growth support to study the effect of acidity on nodulation and plant growth.

Spatial variability of soils in a seasonally dry tropical forest

NASA Astrophysics Data System (ADS)

Pulla, Sandeep; Riotte, Jean; Suresh, Hebbalalu; Dattaraja, Handanakere; Sukumar, Raman

2016-04-01

Soil structures communities of plants and soil organisms in tropical forests. Understanding the controls of soil spatial variability can therefore potentially inform efforts towards forest restoration. We studied the relationship between soils and lithology, topography, vegetation and fire in a seasonally dry tropical forest in southern India. We extensively sampled soil (available nutrients, Al, pH, and moisture), rocks, relief, woody vegetation, and spatial variation in fire burn frequency in a permanent 50-ha plot. Lower elevation soils tended to be less moist and were depleted in several nutrients and clay. The availability of several nutrients was, in turn, linked to whole-rock chemical composition differences since some lithologies were associated with higher elevations, while the others tended to dominate lower elevations. We suggest that local-scale topography in this region has been shaped by the spatial distribution of lithologies, which differ in their susceptibility to weathering. Nitrogen availability was uncorrelated with the presence of trees belonging to Fabaceae, a family associated with N-fixing species. No effect of burning on soil parameters could be discerned at this scale.

[Citrus boron nutrient level and its impact factors in the Three Gorges Reservoir region of Chongqing, China].

PubMed

Zhou, Wei; Peng, Liang-Zhi; Chun, Chang-Pin; Jiang, Cai-Lun; Ling, Li-Li; Wang, Nan-Qi; Xing, Fei; Huang, Yi

2014-04-01

To investigate the level of boron nutrient in citrus and its impact factors, a total of 954 citrus leaf samples and 302 soil samples were collected from representative orchards in the 12 main citrus production counties in the Three Gorges Reservoir region of Chongqing to determine the boron content in citrus leaves, as well as the relationships between leaf boron content with soil available boron content, soil pH value, cultivar, rootstock and the age of tree. Results indicated that the leaf samples from 41.6% orchards (< 35 mg x kg(-1)) and the soil samples from 89.4% orchards (< 0.5 mg x kg(-1)) were boron insufficient. The correlation of leaf boron content and soil available boron content was not significant. The soil pH, cultivar, rootstock and the age of tree did affect the leaf boron content. The leaves from the orchards with soil pH of 4.5-6.4 demonstrated significantly higher boron contents than with the soil pH of 6.5-8.5. The leaf boron contents in the different cultivars was ranged as Satsuma mandarin > pomelo > valencia orange > sweet orange > tangor > navel orange. The citrus on trifoliate orange and sour pomelo rootstocks had significantly higher leaf boron contents than on Carrizo citrange and red tangerine rootstocks. Compared with the adult citrus trees (above 8 year-old), 6.6% more of leaf samples of younger trees (3 to 8 year-old) contained boron contents in the optimum range (35-100 mg x kg(-1)).

CO2-assisted phosphorus extraction from poultry litter and selective recovery of struvite and potassium struvite.

PubMed

Shashvatt, Utsav; Benoit, Josh; Aris, Hannah; Blaney, Lee

2018-06-18

Phosphorus recovery from industrialized poultry operations is necessary to ensure sustainable waste management and resource consumption. To realize these goals, an innovative, two-stage process chemistry has been developed to extract nutrients from poultry litter and recover value-added products. Over 75% phosphorus extraction was achieved by bubbling carbon dioxide into poultry litter slurries and adding strong acid to reach pH 4.5-5.5. After separating the nutrient-deficient poultry litter solids and the nutrient-rich liquid, the extract pH was increased through aeration and strong base addition. Over 95% of the extracted phosphorus was recovered as solid precipitate at pH 8.5-9.0. High-purity struvite and potassium struvite products were selectively recovered through pH control, introduction of a calcium-complexing agent, and addition of magnesium chloride. The nitrogen-to-phosphorus-to-potassium (NPK) ratio of the recovered solids was controlled through aeration and pH adjustment. Precipitation at pH 8.5-9.0 and 10.5-11.0 resulted in NPK ratios of 2.0:1.0:0.1 and 0.9:1.0:0.2, respectively. The process effluent was effectively recycled as makeup water for the subsequent batch of poultry litter, thereby decreasing water consumption and increasing overall nutrient recovery. Sequencing batch operation yielded greater than 70% phosphorus recovery within a 45-min process, demonstrating the potential for this technology to alleviate nutrient pollution in agricultural settings and generate an alternative supply of phosphorus fertilizers. Copyright © 2018. Published by Elsevier Ltd.

Net Primary Productivity and Edaphic Fertility in Two Pluvial Tropical Forests in the Chocó Biogeographical Region of Colombia

PubMed Central

Quinto-Mosquera, Harley

2017-01-01

The net primary productivity (NPP) of tropical forests is a key process of the carbon cycle and therefore for the mitigation of global climate change. It has been proposed that NPP is limited by the availability of soil nutrients in lowland tropical forests and that belowground NPP decreases as edaphic fertility increases. This hypothesis was evaluated in two localities (Opogodó and Pacurita) of the Chocó Biogeographical region, one of the rainiest of the world, where the aboveground (litter and wood) and belowground (fine and coarse roots) components of NPP were measured. Fertility parameters (pH, nutrients, and texture) were also determined and related to NPP. Total NPP was similar between locations (23.7 vs. 24.2 t ha-1 year-1 for Opogodó and Pacurita, respectively). However, components of NPP showed differences: in Pacurita, with steeper topography, NPP of wood and coarse roots were higher; therefore, differences of topography and drainage between localities probably affected the NPP of wood. On the other hand, soils of Opogodó, where NPP of fine roots was higher, showed higher contents of sand, N+, and organic matter (OM). With the increase of pH, OM, N+, K, Mg, and sand, the NPP of leaves and fine roots as well as the percentage of NPP belowground also increased, which suggests NPP limitation by multiple nutrients. The increase of NPP belowground with the availability of edaphic nutrients evidenced a redistribution of the aboveground and belowground components of NPP with the increase of soil fertility in oligotrophic systems, probably as a mechanism to improve the capture of resources. PMID:28114418

Net Primary Productivity and Edaphic Fertility in Two Pluvial Tropical Forests in the Chocó Biogeographical Region of Colombia.

PubMed

Quinto-Mosquera, Harley; Moreno, Flavio

2017-01-01

The net primary productivity (NPP) of tropical forests is a key process of the carbon cycle and therefore for the mitigation of global climate change. It has been proposed that NPP is limited by the availability of soil nutrients in lowland tropical forests and that belowground NPP decreases as edaphic fertility increases. This hypothesis was evaluated in two localities (Opogodó and Pacurita) of the Chocó Biogeographical region, one of the rainiest of the world, where the aboveground (litter and wood) and belowground (fine and coarse roots) components of NPP were measured. Fertility parameters (pH, nutrients, and texture) were also determined and related to NPP. Total NPP was similar between locations (23.7 vs. 24.2 t ha-1 year-1 for Opogodó and Pacurita, respectively). However, components of NPP showed differences: in Pacurita, with steeper topography, NPP of wood and coarse roots were higher; therefore, differences of topography and drainage between localities probably affected the NPP of wood. On the other hand, soils of Opogodó, where NPP of fine roots was higher, showed higher contents of sand, N+, and organic matter (OM). With the increase of pH, OM, N+, K, Mg, and sand, the NPP of leaves and fine roots as well as the percentage of NPP belowground also increased, which suggests NPP limitation by multiple nutrients. The increase of NPP belowground with the availability of edaphic nutrients evidenced a redistribution of the aboveground and belowground components of NPP with the increase of soil fertility in oligotrophic systems, probably as a mechanism to improve the capture of resources.

Monitoring the Productivity of Coastal Systems Using PH ...

EPA Pesticide Factsheets

The impact of nutrient inputs to the eutrophication of coastal ecosystems has been one of the great themes of coastal ecology. There have been countless studies devoted to quantifying how human sources of nutrients, in particular nitrogen (N), effect coastal water bodies. These studies, which often measure in situ concentrations of nutrients, chlorophyll, and dissolved oxygen, are often spatially and/or temporally intensive and expensive. We provide evidence from experimental mesocosms, coupled with data from the water column of a well-mixed estuary, that pH can be a quick, inexpensive, and integrative measure of net ecosystem metabolism. In some cases, this approach is a more sensitive tracer of production than direct measurements of chlorophyll and carbon-14. Taken together, our data suggest that pH is a sensitive, but often overlooked, tool for monitoring estuarine production. This presentation will explore the potential utility of pH as an indicator of ecosystem productivity. Our data suggest that pH is a sensitive and potentially integrator of net ecosystem production. It should not be overlooked, that measuring pH is quick, easy, and inexpensive, further increasing its value as an analytical tool.

Beneficial effects of humic acid on micronutrient availability to wheat

NASA Technical Reports Server (NTRS)

Mackowiak, C. L.; Grossl, P. R.; Bugbee, B. G.

2001-01-01

Humic acid (HA) is a relatively stable product of organic matter decomposition and thus accumulates in environmental systems. Humic acid might benefit plant growth by chelating unavailable nutrients and buffering pH. We examined the effect of HA on growth and micronutrient uptake in wheat (Triticum aestivum L.) grown hydroponically. Four root-zone treatments were compared: (i) 25 micromoles synthetic chelate N-(4-hydroxyethyl)ethylenediaminetriacetic acid (C10H18N2O7) (HEDTA at 0.25 mM C); (ii) 25 micromoles synthetic chelate with 4-morpholineethanesulfonic acid (C6H13N4S) (MES at 5 mM C) pH buffer; (iii) HA at 1 mM C without synthetic chelate or buffer; and (iv) no synthetic chelate or buffer. Ample inorganic Fe (35 micromoles Fe3+) was supplied in all treatments. There was no statistically significant difference in total biomass or seed yield among treatments, but HA was effective at ameliorating the leaf interveinal chlorosis that occurred during early growth of the nonchelated treatment. Leaf-tissue Cu and Zn concentrations were lower in the HEDTA treatment relative to no chelate (NC), indicating HEDTA strongly complexed these nutrients, thus reducing their free ion activities and hence, bioavailability. Humic acid did not complex Zn as strongly and chemical equilibrium modeling supported these results. Titration tests indicated that HA was not an effective pH buffer at 1 mM C, and higher levels resulted in HA-Ca and HA-Mg flocculation in the nutrient solution.

Effect of interactions on the nutrient status of a tropical soil treated with green manures and inorganic phosphate fertilizers.

PubMed

Bah, Abdul R; Rahman, Zaharah A; Hussin, Aminuddin

2004-06-08

Integrated nutrient management systems using plant residues and inorganic P fertilizers have high potential for increasing crop production and ensuring sustainability in the tropics, but their adoption requires in-depth understanding of nutrient dynamics in such systems. This was examined in a highly weathered tropical soil treated with green manures (GMs) and P fertilizers in two experiments conducted in the laboratory and glasshouse. The treatments were factorial combinations of the GMs (Calopogonium caeruleum, Gliricidia sepium, and Imperata cylindrica) and P fertilizers (phosphate rocks [PRs] from North Carolina, China, and Algeria, and triple superphosphate) replicated thrice. Olsen P, mineral N, pH, and exchangeable K, Ca, and Mg were monitored in a laboratory incubation study for 16 months. The change in soil P fractions and available P was also determined at the end of the study. Phosphorus available from the amendments was quantified at monthly intervals for 5 months by 33P-32P double isotopic labeling in the glasshouse using Setaria sphacelata as test crop. The GMs were labeled with 33P to determine their contribution to P taken up by Setaria, while that from the P fertilizers was indirectly measured by labeling the soil with 32P. The P fertilizers hardly changed Olsen P and exchangeable cations during 16 months of incubation. The legume GMs and legume GM+P did not change Olsen P, lowered exchangeable Ca, and increased exchangeable K about threefold (4.5 cmol[+]kg(-1) soil) in the first 4 months, even as large amounts of NH4-N accumulated (approximately 1000 mg kg soil(-1)) and soil pH increased to more than 6.5. Afterwards, Olsen P and exchangeable Ca and Mg increased (threefold) as NH4+-N and soil pH declined. The legume GMs also augmented reversibly sorbed P in Al-P and Fe-P fractions resulting in high residual effect in the soil, while fertilizer-P was irreversibly retained. The GMs increased PR-P utilization by 40 to over 80%, mobilized soil P, and markedly enhanced uptake of N, K, Ca, and Mg. Thus GMs+PRs is an appropriate combination for correcting nutrient deficiencies in tropical soils.

75 FR 22589 - Preliminary Listing of an Additional Water to Wisconsin's 2008 List of Waters Under Section 303(d...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-29

... to the presence of excessive nutrients, including phosphorus, elevated pH values, as well as the... Wisconsin does not have numeric criterian for phosphorus and WDNR did not believe that the available data..., and that the Bay was not impaired due to phosphorus. WDNR stated that it will continue to monitor...

Comparing Measures of Estuarine Ecosystem Production in a ...

EPA Pesticide Factsheets

Anthropogenic nutrient enrichments and concerted efforts at nutrient reductions, compounded with the influences of climate change, are likely changing the net ecosystem production (NEP) of our coastal systems. To quantify these changes, scientists monitor a range of physical, chemical, and biological parameters sampled at various frequencies. Water column chlorophyll concentrations are arguably the most commonly used indicator of net phytoplankton production, as well as a coarse indicator of NEP. We compared parameters that estimate production, including chlorophyll, across an experimental nutrient gradient and in situ in both well-mixed and stratified estuarine environments. Data from an experiment conducted in the early 1980s in mesocosms designed to replicate a well-mixed mid-Narragansett Bay (Rhode Island) water column were used to correlate changes in chlorophyll concentrations, pH, dissolved oxygen (O2), dissolved inorganic nitrogen, phosphate, and silicate concentrations, cell counts, and 14C carbon uptake measurements across a range of nutrient enrichments. The pH, O2, nutrient, and cell count measurements reflected seasonal cycles of spring blooms followed by late summer/early fall respiration periods across nutrient enrichments. Chlorophyll concentrations were more variable and rates of 14C productivity were inconsistent with observed trends in nutrient concentrations, pH, and O2 concentrations. Similar comparisons were made using data from a well-mixe

Carbon and nitrogen dynamics across a bedrock-regulated subarctic pH gradient

NASA Astrophysics Data System (ADS)

Tomczyk, N.; Heim, E. W.; Sadowsky, J.; Remiszewski, K.; Varner, R. K.; Bryce, J. G.; Frey, S. D.

2014-12-01

Bedrock geochemistry has been shown to influence landscape evolution due to nutrient limitation on primary production. There may also be less direct interactions between bedrock-derived chemicals and ecosystem function. Effects of calcium (Ca) and pH on soil carbon (C) and nitrogen (N) cycling have been shown in acid impacted forests o f North America. Understanding intrinsic factors that affect C and nutrient dynamics in subarctic ecosystems has implications for how these ecosystems will respond to a changing climate. How the soil microbial community allocates enzymes to acquire resources from the environment can indicate whether a system is nutrient or energy limited. This study examined whether bedrock geochemistry exerts pressure on nutrient cycles in the overlying soils. In thin, weakly developed soils, bedrock is the primary mineral material and is a source of vital nutrients. Nitrogen (N) and C are not derived from bedrock, but their cycling is still affected by reactions with geologically-derived chemicals. Our study sites near Abisko, Sweden (~68°N) were selected adjacent to five distinct bedrock outcrops (quartzite, slate, carbonate, and two different metasedimenty units). All sites were at a similar elevation (~700 m a.s.l.) and had similar vegetation (subarctic heath). Nutrient concentrations in bedrock and soils were measured in addition to soil microbial biomass and extracellular enzyme activity. We found a statistically significant correlation between soil Ca concentrations and soil pH (r = 0.88, p < 0.01). There were also significant relationships between soil pH and the ratio of C-acquiring to N-acquiring enzyme activity (r = -0.89, p < 0.01), soil pH and soil C-to-N ratio (r = -0.76, p < 0.01), and the ratio of C-acquiring to N-acquiring enzyme activity and soil C-to-N ratio (r = 0.78, p < 0.01). These results suggest that soil Ca concentrations influence C and N cycling dynamics in these soils through their effect on soil pH.

Dynamics of soil available phosphorus and its impact factors under simulated climate change in typical farmland of Taihu Lake region, China.

PubMed

Yu, Kaihao; Chen, Xiaomin; Pan, Genxing; Zhang, Xuhui; Chen, Can

2016-02-01

Global climate change affects the availability of soil nutrients, thereby influencing crop productivity. This research was conducted to investigate the effects of elevated CO2, elevated temperature, and the interaction of the elevated CO2 and temperature on the soil available phosphorus (P) of a paddy-wheat rotation in the Taihu Lake region, China. Winter wheat (Triticum aestivum L.) was cultivated during the study period from 2011 to 2014 at two CO2 levels (350 μL•L(-1) ambient and 500 μL•L(-1) elevated by 150 μL•L(-1)) and two temperatures (ambient and 2 °C above the ambient). Soil available P content increased at the first season and decreased at the last season during the three wheat growing seasons. Soil available P content showed seasonal variation, whereas dynamic changes were not significant within each growing season. Soil available P content had no obvious trends under different treatments. But for the elevated temperature, CO2, and their combination treatments, soil available P content decreased in a long time period. During the period of wheat ripening stage, significant positive correlations were found between soil available P content and saturated hydraulic conductivity (Ks) and organic matter, but significant negative correlations with soil clay content and pH value; the correlation coefficients were 0.9400 (p < 0.01), 0.9942 (p < 0.01), -0.9383 (p < 0.01), and -0.6403 (p < 0.05), respectively. Therefore, Ks, organic matter, soil clay, and pH were the major impact factors on soil available P content. These results can provide a basis for predicting the trend of soil available P variation, as well as guidance for managing the soil nutrients and best fertilization practices in the future climate change scenario.

Cellular Oxygen and Nutrient Sensing in Microgravity Using Time-Resolved Fluorescence Microscopy

NASA Technical Reports Server (NTRS)

Szmacinski, Henryk

2003-01-01

Oxygen and nutrient sensing is fundamental to the understanding of cell growth and metabolism. This requires identification of optical probes and suitable detection technology without complex calibration procedures. Under this project Microcosm developed an experimental technique that allows for simultaneous imaging of intra- and inter-cellular events. The technique consists of frequency-domain Fluorescence Lifetime Imaging Microscopy (FLIM), a set of identified oxygen and pH probes, and methods for fabrication of microsensors. Specifications for electronic and optical components of FLIM instrumentation are provided. Hardware and software were developed for data acquisition and analysis. Principles, procedures, and representative images are demonstrated. Suitable lifetime sensitive oxygen, pH, and glucose probes for intra- and extra-cellular measurements of analyte concentrations have been identified and tested. Lifetime sensing and imaging have been performed using PBS buffer, culture media, and yeast cells as a model systems. Spectral specifications, calibration curves, and probes availability are also provided in the report.

The Effects of Lime, Fertilizer, and Herbicide on Forest Soil Solution Chemistry and Northern Red Oak Radial Growth Following Shelterwood Harvest

Treesearch

Angela M Happel; William E. Sharpe

2004-01-01

Soil acidity, nutrient deficient soils, lack of light penetration, herbivory, and understory competition are the major obstacles encountered in regenerating and sustaining northern red oak. Changes in soils that may occur during soil acidifi- cation include: reduced soil pH, increased availability of aluminum (Al) and manganese (Mn), loss of base cations due to...

Effect of wood ash application on soil solution chemistry of tropical acid soils: incubation study.

PubMed

Nkana, J C Voundi; Demeyer, A; Verloo, M G

2002-12-01

The objective of this study was to determine the effect of wood ash application on soil solution composition of three tropical acid soils. Calcium carbonate was used as a reference amendment. Amended soils and control were incubated for 60 days. To assess soluble nutrients, saturation extracts were analysed at 15 days intervals. Wood ash application affects the soil solution chemistry in two ways, as a liming agent and as a supplier of nutrients. As a liming agent, wood ash application induced increases in soil solution pH, Ca, Mg, inorganic C, SO4 and DOC. As a supplier of elements, the increase in the soil solution pH was partly due to ligand exchange between wood ash SO4 and OH- ions. Large increases in concentrations of inorganic C, SO4, Ca and Mg with wood ash relative to lime and especially increases in K reflected the supply of these elements by wood ash. Wood ash application could represent increased availability of nutrients for the plant. However, large concentrations of basic cations, SO4 and NO3 obtained with higher application rates could be a concern because of potential solute transport to surface waters and groundwater. Wood ash must be applied at reasonable rates to avoid any risk for the environment.

[Nutrients in atmospheric wet deposition in the East China Sea].

PubMed

Zhu, Yu-Mei; Liu, Su-Mei

2011-09-01

92 rainwater samples were collected at Shengsi Archipelago from January 2008 to December 2009. The pH and the concentrations of nutrients (NH4(+), NO3(-) + NO2(-), PO4(3-), SiO3(2-)) were analyzed using spectrophotometry to understand the impacts of the atmospheric wet deposition on the ecosystem of the East China Sea. The results showed that the pH of 85% samples were less than 5.0, and had significant effect on the environment. There were significant differences among monthly average concentrations of nutrients and rainfall and seasonal average wet deposition of nutrients in investigation periods. The annual average wet deposition flux was 52.05 mmol x (m2 x a) (-1) for DIN, 0.08 mmol x (m2 x a) (-1) for PO4(3-), 2.05 mmol x (m2 x a) (-1) for SiO3(2-). The average molar ratios of NO3(-)/NH4(+) is 0.73, N: P ratio is 684: 1, indicating that nutrients composition in rainwater was different from seawater of the East China Sea Shelf (10-150). The wet deposition may change the nutrients structure, pH and lead to change the phytoplankton production in the surface seawater of the East China Sea, even lead to the red tide.

Soil microbial and nutrient responses to 7 years of seasonally altered precipitation in a Chihuahuan Desert grassland.

PubMed

Bell, Colin W; Tissue, David T; Loik, Michael E; Wallenstein, Matthew D; Acosta-Martinez, Veronica; Erickson, Richard A; Zak, John C

2014-05-01

Soil microbial communities in Chihuahuan Desert grasslands generally experience highly variable spatiotemporal rainfall patterns. Changes in precipitation regimes can affect belowground ecosystem processes such as decomposition and nutrient cycling by altering soil microbial community structure and function. The objective of this study was to determine if increased seasonal precipitation frequency and magnitude over a 7-year period would generate a persistent shift in microbial community characteristics and soil nutrient availability. We supplemented natural rainfall with large events (one/winter and three/summer) to simulate increased precipitation based on climate model predictions for this region. We observed a 2-year delay in microbial responses to supplemental precipitation treatments. In years 3-5, higher microbial biomass, arbuscular mycorrhizae abundance, and soil enzyme C and P acquisition activities were observed in the supplemental water plots even during extended drought periods. In years 5-7, available soil P was consistently lower in the watered plots compared to control plots. Shifts in soil P corresponded to higher fungal abundances, microbial C utilization activity, and soil pH. This study demonstrated that 25% shifts in seasonal rainfall can significantly influence soil microbial and nutrient properties, which in turn may have long-term effects on nutrient cycling and plant P uptake in this desert grassland. © 2013 John Wiley & Sons Ltd.

Role of nutrients and illuminance in predicting the fate of fungal mediated petroleum hydrocarbon degradation and biomass production.

PubMed

Ali Khan, Aqib Hassan; Tanveer, Sundus; Anees, Mariam; Muhammad, Yousaf Shad; Iqbal, Mazhar; Yousaf, Sohail

2016-07-01

Biodegradation and biomass production are affected by numerous environmental factors including pH, oxygen availability and presence of pollutants. The present study, for the first time, elucidated the effects of nutrients and light on mycodegradation of petroleum hydrocarbons in diesel oil. Seven fungal strains (Aspergillus terreus FA3, Aspergillus niger FA5, Aspergillus terreus FA6, Penicillium chrysogenum FP4, Aspergillus terreus FP6, Aspergillus flavus FP10, and Candida sp. FG1) were used for hydrocarbon degradation under static conditions, in four combinations of nutrient media and illuminance for 45 days. Highest degradation was achieved by Aspergillus terreus FA6 and Candida sp. FG1 under both conditions of light and dark, with nutrient deprived HAF (Hydrocarbon adopted fungi) broth. Under HAF/Dark diesel oil degradation by FA6 and FG1 was 87.3% and 84.3% respectively, while under HAF/Light both FA6 and FG1 performed 84.3% biodegradation. The highest biomass was produced by Aspergillus flavus FP10 in PDB (Potato dextrose broth)/Dark (109.3 mg). Fungal degradation of petroleum hydrocarbons was negatively affected by the presence of other simpler-to-degrade carbon sources in the medium. The biomass production was enhanced by improved nutrient availability and diminished by illuminance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Optimization and performance evaluation for nutrient removal from palm oil mill effluent wastewater using microalgae

NASA Astrophysics Data System (ADS)

Ibrahim, Raheek I.; Wong, Z. H.; Mohammad, A. W.

2015-04-01

Palm oil mill effluent (POME) wastewater was produced in huge amounts in Malaysia, and if it discharged into the environment, it causes a serious problem regarding its high content of nutrients. This study was devoted to POME wastewater treatment with microalgae. The main objective was to find the optimum conditions (retention time, and pH) in the microalgae treatment of POME wastewater considering retention time as a most important parameter in algae treatment, since after the optimum conditions there is a diverse effect of time and pH and so, the process becomes costly. According to our knowledge, there is no existing study optimized the retention time and pH with % removal of nutrients (ammonia nitrogen NH3-N, and orthophosphorous PO43-) for microalgae treatment of POME wastewater. In order to achieve with optimization, a central composite rotatable design with a second order polynomial model was used, regression coefficients and goodness of fit results in removal percentages of nutrients (NH3-N, and PO43-) were estimated.WinQSB technique was used to optimize the surface response objective functionfor the developed model. Also experiments were done to validate the model results.The optimum conditions were found to be 18 day retention time for ammonia nitrogen, and pH of 9.22, while for orthophosphorous, 15 days were indicated as the optimum retention time with a pH value of 9.2.

Soil Parameters Drive the Structure, Diversity and Metabolic Potentials of the Bacterial Communities Across Temperate Beech Forest Soil Sequences.

PubMed

Jeanbille, M; Buée, M; Bach, C; Cébron, A; Frey-Klett, P; Turpault, M P; Uroz, S

2016-02-01

Soil and climatic conditions as well as land cover and land management have been shown to strongly impact the structure and diversity of the soil bacterial communities. Here, we addressed under a same land cover the potential effect of the edaphic parameters on the soil bacterial communities, excluding potential confounding factors as climate. To do this, we characterized two natural soil sequences occurring in the Montiers experimental site. Spatially distant soil samples were collected below Fagus sylvatica tree stands to assess the effect of soil sequences on the edaphic parameters, as well as the structure and diversity of the bacterial communities. Soil analyses revealed that the two soil sequences were characterized by higher pH and calcium and magnesium contents in the lower plots. Metabolic assays based on Biolog Ecoplates highlighted higher intensity and richness in usable carbon substrates in the lower plots than in the middle and upper plots, although no significant differences occurred in the abundance of bacterial and fungal communities along the soil sequences as assessed using quantitative PCR. Pyrosequencing analysis of 16S ribosomal RNA (rRNA) gene amplicons revealed that Proteobacteria, Acidobacteria and Bacteroidetes were the most abundantly represented phyla. Acidobacteria, Proteobacteria and Chlamydiae were significantly enriched in the most acidic and nutrient-poor soils compared to the Bacteroidetes, which were significantly enriched in the soils presenting the higher pH and nutrient contents. Interestingly, aluminium, nitrogen, calcium, nutrient availability and pH appeared to be the best predictors of the bacterial community structures along the soil sequences.

[Effects of plateau zokor disturbance and restoration years on soil nutrients and microbial functional diversity in alpine meadow].

PubMed

Hu, Lei; Ade, Lu-ji; Zi, Hong-biao; Wang, Chang-ting

2015-09-01

To explore the dynamic process of restoration succession in degraded alpine meadow that had been disturbed by plateau zokors in the eastern Tibetan Plateau, we examined soil nutrients and microbial functional diversity using conventional laboratory analysis and the Biolog-ECO microplate method. Our study showed that: 1) The zokors disturbance significantly reduced soil organic matter, total nitrogen, available nitrogen and phosphorus contents, but had no significant effects on soil total phosphorus and potassium contents; 2) Soil microbial carbon utilization efficiency, values of Shannon, Pielou and McIntosh indexes increased with alpine meadow restoration years; 3) Principal component analysis (PCA) showed that carbohydrates and amino acids were the main carbon sources for maintaining soil microbial community; 4) Redundancy analysis ( RDA) indicated that soil pH, soil organic matter, total nitrogen, available nitrogen, and total potassium were the main factors influencing the metabolic rate of soil microbial community and microbial functional diversity. In summary, variations in soil microbial functional diversity at different recovery stages reflected the microbial response to aboveground vegetation, soil microbial composition and soil nutrients.

Endophytic fungal diversity of Fragaria vesca, a crop wild relative of strawberry, along environmental gradients within a small geographical area

PubMed Central

Yokoya, Kazutomo; Postel, Sarah; Fang, Rui

2017-01-01

Background Fungal endophytes are highly diverse ubiquitous asymptomatic microorganisms, some of which appear to be symbiotic. Depending on abiotic conditions and genotype of the plant, the diversity of endophytes may confer fitness benefits to plant communities. Methods We studied a crop wild relative (CWR) of strawberry, along environmental gradients with a view to understand the cultivable root-derived endophytic fungi that can be evaluated for promoting growth and tolerating stress in selected plant groups. The main objectives were to understand whether: (a) suboptimal soil types are drivers for fungal distribution and diversity; (b) high pH and poor nutrient availability lead to fungal-plant associations that help deliver fitness benefits; and (c) novel fungi can be identified for their use in improving plant growth, and alleviate stress in diverse crops. Results The study revealed that habitats with high pH and low nutrient availability have higher fungal diversity, with more rare fungi isolated from locations with chalky soil. Plants from location G were the healthiest even though soil from this location was the poorest in nutrients. Study of environmental gradients, especially extreme habitat types, may help understand the root zone fungal diversity of different functional classes. Two small in vitro pilot studies conducted with two isolates showed that endophytic fungi from suboptimal habitats can promote plant growth and fitness benefits in selected plant groups. Discussion Targeting native plants and crop wild relatives for research offers opportunities to unearth diverse functional groups of root-derived endophytic fungi that are beneficial for crops. PMID:28168102

Water-quality assessment of Francis E Walter reservoir, Luzerne and Carbon counties, Pennsylvania

USGS Publications Warehouse

Barker, J.L.

1983-01-01

Water-quality data, both past and present, show that the waters of the upper Lehigh River basin are somewhat acidic, but otherwise are generally of good quality. This report contains a summary of all known water-quality data collected by the U.S. Geological Survey and other agencies, as well as a synopsis of current water-quality conditions in the reservoir and its tributaries. Water-quality data collected from June 1981 to May 1982 indicate that raising the pool level from 1,300 to approximately 1,392 feet above sea level (NGVD of 1929) has had some significant, if only temporary, detrimental impacts on the reservoir system and its discharge. Depth profile measurements show that, while the impoindment was thermally stratified for only about 2 weeks, the dissolved oxygen concentrations were depressed to levels critical to fishlife throughout much of the reservoir. Another effect of the raised pool was the lowering of pH in the impoinded water. Median pH values were less than 6.0 throughout the reservoir, whereas they commonly exceeded 6.5 at the normal pool elevation. Tests for fecal coliform and fecal streptococcus indicate the impoinded water is nearly free of enteric bacteria. Algal analyses and nutrient concentrations support the premise that the impoundment is nutrient poor and phosphorus limited. Raising the water level an additional 125 feet should have no permanent detrimental effect upon water quality and will greatly increase available habitat for fish and waterflow. Increased retention time should not alter the current trophic status and may decrease the concentration of available nutrients.

Effects of biochar, waste water irrigation and fertilization on soil properties in West African urban agriculture.

PubMed

Häring, Volker; Manka'abusi, Delphine; Akoto-Danso, Edmund K; Werner, Steffen; Atiah, Kofi; Steiner, Christoph; Lompo, Désiré J P; Adiku, Samuel; Buerkert, Andreas; Marschner, Bernd

2017-09-06

In large areas of sub-Saharan Africa crop production must cope with low soil fertility. To increase soil fertility, the application of biochar (charred biomass) has been suggested. In urban areas, untreated waste water is widely used for irrigation because it is a nutrient-rich year-round water source. Uncertainty exists regarding the interactions between soil properties, biochar, waste water and fertilization over time. The aims of this study were to determine these interactions in two typical sandy, soil organic carbon (SOC) and nutrient depleted soils under urban vegetable production in Tamale (Ghana) and Ouagadougou (Burkina Faso) over two years. The addition of biochar at 2 kg m -2 made from rice husks and corn cobs initially doubled SOC stocks but SOC losses of 35% occurred thereafter. Both biochar types had no effect on soil pH, phosphorous availability and effective cation exchange capacity (CEC) but rice husk biochar retained nitrogen (N). Irrigation with domestic waste water increased soil pH and exchangeable sodium over time. Inorganic fertilization alone acidified soils, increased available phosphorous and decreased base saturation. Organic fertilization increased SOC, N and CEC. The results from both locations demonstrate that the effects of biochar and waste water were less pronounced than reported elsewhere.

Steel Slag and Shredded Tires as Media for Blind Inlets to Improve Water Quality

NASA Astrophysics Data System (ADS)

Gonzalez, J. M.; Smith, D. R.; Livingston, S.

2015-12-01

Off-site transport of contaminants through surface runoff affects water quality. Blind inlets are proven conservation practices for reducing surface runoff, and consequently reducing nutrient loadings from small agricultural closed depressions to water bodies. Gravel is the most widely used blind inlet media to reduce flow, but not to sorb contaminants from the water. Readily available byproducts, such as steel slag and shredded tires, could be used as alternative media in blind inlets to sorb nutrients and pesticides from surface runoff. Sorption isotherms were performed to investigate the sorption capabilities of steel slag and shredded tires for phosphate and atrazine in electrolyte background solutions containing either 10 mM CaCl2 or KCl. Results of this research demonstrated that phosphate and atrazine were irreversibly sorbed by the steel slag and shredded tires. The steel slag increased the pH solution increased about 4 pH units after the sorption step; while the pH of the solution with shredded tires remained the same. Desorption of the phosphate and atrazine was low from the steel slag and shredded tires, respectively. Thus, the above results suggest that the steel slag and shredded tires can potentially be used as media to sorb phosphate and atrazine, respectively.

The influence of soil properties and nutrients on conifer forest growth in Sweden, and the first steps in developing a nutrient availability metric

NASA Astrophysics Data System (ADS)

Van Sundert, Kevin; Horemans, Joanna A.; Stendahl, Johan; Vicca, Sara

2018-06-01

The availability of nutrients is one of the factors that regulate terrestrial carbon cycling and modify ecosystem responses to environmental changes. Nonetheless, nutrient availability is often overlooked in climate-carbon cycle studies because it depends on the interplay of various soil factors that would ideally be comprised into metrics applicable at large spatial scales. Such metrics do not currently exist. Here, we use a Swedish forest inventory database that contains soil data and tree growth data for > 2500 forests across Sweden to (i) test which combination of soil factors best explains variation in tree growth, (ii) evaluate an existing metric of constraints on nutrient availability, and (iii) adjust this metric for boreal forest data. With (iii), we thus aimed to provide an adjustable nutrient metric, applicable for Sweden and with potential for elaboration to other regions. While taking into account confounding factors such as climate, N deposition, and soil oxygen availability, our analyses revealed that the soil organic carbon concentration (SOC) and the ratio of soil carbon to nitrogen (C : N) were the most important factors explaining variation in normalized (climate-independent) productivity (mean annual volume increment - m3 ha-1 yr-1) across Sweden. Normalized forest productivity was significantly negatively related to the soil C : N ratio (R2 = 0.02-0.13), while SOC exhibited an empirical optimum (R2 = 0.05-0.15). For the metric, we started from a (yet unvalidated) metric for constraints on nutrient availability that was previously developed by the International Institute for Applied Systems Analysis (IIASA - Laxenburg, Austria) for evaluating potential productivity of arable land. This IIASA metric requires information on soil properties that are indicative of nutrient availability (SOC, soil texture, total exchangeable bases - TEB, and pH) and is based on theoretical considerations that are also generally valid for nonagricultural ecosystems. However, the IIASA metric was unrelated to normalized forest productivity across Sweden (R2 = 0.00-0.01) because the soil factors under consideration were not optimally implemented according to the Swedish data, and because the soil C : N ratio was not included. Using two methods (each one based on a different way of normalizing productivity for climate), we adjusted this metric by incorporating soil C : N and modifying the relationship between SOC and nutrient availability in view of the observed relationships across our database. In contrast to the IIASA metric, the adjusted metrics explained some variation in normalized productivity in the database (R2 = 0.03-0.21; depending on the applied method). A test for five manually selected local fertility gradients in our database revealed a significant and stronger relationship between the adjusted metrics and productivity for each of the gradients (R2 = 0.09-0.38). This study thus shows for the first time how nutrient availability metrics can be evaluated and adjusted for a particular ecosystem type, using a large-scale database.

Nutrient leaching, soil pH and changes in microbial community increase with time in lead-contaminated boreal forest soil at a shooting range area.

PubMed

Selonen, Salla; Setälä, Heikki

2017-02-01

Despite the known toxicity of lead (Pb), Pb pellets are widely used at shotgun shooting ranges over the world. However, the impacts of Pb on soil nutrients and soil microbes, playing a crucial role in nutrient cycling, are poorly understood. Furthermore, it is unknown whether these impacts change with time after the cessation of shooting. To shed light on these issues, three study sites in the same coniferous forest in a shooting range area were studied: an uncontaminated control site and an active and an abandoned shooting range, both sharing a similar Pb pellet load in the soil, but the latter with a 20-year longer contamination history. Soil pH and nitrate concentration increased, whilst soil phosphate concentration and fungal phospholipid fatty acid (PLFA) decreased due to Pb contamination. Our results imply that shooting-derived Pb can influence soil nutrients and microbes not only directly but also indirectly by increasing soil pH. However, these mechanisms cannot be differentiated here. Many of the Pb-induced changes were most pronounced at the abandoned range, and nutrient leaching was increased only at that site. These results suggest that Pb disturbs the structure and functions of the soil system and impairs a crucial ecosystem service, the ability to retain nutrients. Furthermore, the risks of shooting-derived Pb to the environment increase with time.

Moving towards sustainable resources: Recovery and fractionation of nutrients from dairy manure digestate using membranes.

PubMed

Gerardo, Michael L; Aljohani, Nasser H M; Oatley-Radcliffe, Darren L; Lovitt, Robert W

2015-09-01

The fractionation of nitrogen (as ammonia/ammonium) and phosphorus (as phosphate ions) present in the dairy manure digestate was investigated using a nanofiltration membrane NF270. The filtration and separation efficiencies were correlated to pH across the range 3 < pH < 11. Filtration at pH 11 enabled higher permeate flux of 125-150 LMH at 20 bar, however rejection of ammonia was high at 30-36% and phosphate was 96.4-97.2%. At pH 3 and pH 7, electrostatic charge effects led to higher permeation of ammonium and thus more efficient separation of nitrogen. The rejection of phosphorus was relatively constant at any given pH and determined as 83% at pH 3, 97% at pH 7 and 95% at pH 11. The fractionation of nitrogen and phosphorus from complex aqueous solutions was demonstrated to be highly dependent on the charge of the membrane and ionic speciation. Solutions rich in nitrogen (as ammonia/ammonium) were obtained with almost no phosphorus present (<1 ppm) whilst the purification of the PO4-P was achieved by series of diafiltration (DF) operations which further separated the nitrogen. The separation of nutrients benefited from an advantageous membrane process with potential added value for a wide range of industries. The analysis of the process economics for a membrane based plant illustrates that the recovery of nutrients, particularly NH3-N, may be commercially feasible when compared to manufactured anhydrous NH3. Copyright © 2015 Elsevier Ltd. All rights reserved.

Irrigation and weed control alter soil microbiology and nutrient availability in North Carolina Sandhill peach orchards.

PubMed

Zhang, Yi; Wang, Liangju; Yuan, Yongge; Xu, Jing; Tu, Cong; Fisk, Connie; Zhang, Weijian; Chen, Xin; Ritchie, David; Hu, Shuijin

2018-02-15

Orchard management practices such as weed control and irrigation are primarily aimed at maximizing fruit yields and economic profits. However, the impact of these practices on soil fertility and soil microbiology is often overlooked. We conducted a two-factor experimental manipulation of weed control by herbicide and trickle irrigation in a nutrient-poor peach (Prunus persica L. cv. Contender) orchard near Jackson Springs, North Carolina. After three and eight years of treatments, an array of soil fertility parameters were examined, including soil pH, soil N, P and cation nutrients, microbial biomass and respiration, N mineralization, and presence of arbuscular mycorrhizal fungi (AMF). Three general trends emerged: 1) irrigation significantly increased soil microbial biomass and activity, 2) infection rate of mycorrhizal fungi within roots were significantly higher under irrigation than non-irrigation treatments, but no significant difference in the AMF community composition was detected among treatments, 3) weed control through herbicides reduced soil organic matter, microbial biomass and activity, and mineral nutrients, but had no significant impacts on root mycorrhizal infection and AMF communities. Weed-control treatments directly decreased availability of soil nutrients in year 8, especially soil extractable inorganic N. Weed control also appears to have altered the soil nutrients via changes in soil microbes and altered net N mineralization via changes in soil microbial biomass and activity. These results indicate that long-term weed control using herbicides reduces soil fertility through reducing organic C inputs, nutrient retention and soil microbes. Together, these findings highlight the need for alternative practices such as winter legume cover cropping that maintain and/or enhance organic inputs to sustain the soil fertility. Copyright © 2017 Elsevier B.V. All rights reserved.

Micronutrients in Soils, Crops, and Livestock

NASA Astrophysics Data System (ADS)

Gupta, Umesh C.; Wu, Kening; Liang, Siyuan

Micronutrient concentrations are generally higher in the surface soil and decrease with soil depth. In spite of the high concentration of most micronutrients in soils, only a small fraction is available to plants. Micronutrients, also known as trace elements, are required in microquantities but their lack can cause serious crop production and animal health problems. Crops vary considerably in their response to various micronutrients. Brassicas and legumes are highly responsive to molybdenum (Mo) and boron (B), whereas corn and other cereals are more responsive to zinc (Zn) and copper (Cu). Micronutrient deficiencies are more common in humid temperate regions, as well as in humid tropical regions, because of intense leaching associated with high precipitation. Soil pH is one of the most important factors affecting the availability of micronutrients to plants. With increasing pH, the availability of these nutrients is reduced with the exception of Mo whose availability increases as soil pH increases. In most plant species, leaves contain higher amounts of nutrients than other plant parts. Therefore, whenever possible, leaves should be sampled to characterize the micronutrient status of crops. Deficiency symptoms for most micronutrients appear on the younger leaves at the top of the plant, whereas toxicity symptoms generally appear on the older leaves of plants. As summarized by Deckers and Steinnes, micronutrient deficiencies are widespread in developing countries, which have much poorer soil resources than the fertile soils of Europe and North America. Many of these areas lie in the humid tropics with extremely infertile, highly weathered, and/or highly leached soils, which are intensely deficient in nutrients. The rest of such soils are in the semiarid and areas adjacent to the latter, where alkaline and calcareous soil conditions severely limit the availability of micronutrients to plants. Frequently, the Cu, iron (Fe), manganese (Mn), Zn, and selenium (Se) levels in forages, which are sufficient for optimum crop yields, are not adequate to meet the needs of livestock. Selenium is a trace mineral, which is not required by plants, and maximum forage yields can be obtained on soils with very low amounts of soil Se. However, if animals are fed feed crops and forages with low Se, they could suffer from serious muscular disorders and other diseases. White muscle disease caused by Se deficiency is the most common disorder and is found in calves and lambs. Sufficiency levels of micronutrients for crops have been discussed in relation to the animal requirement.

Biochar derived from corn straw affected availability and distribution of soil nutrients and cotton yield.

PubMed

Tian, Xiaofei; Li, Chengliang; Zhang, Min; Wan, Yongshan; Xie, Zhihua; Chen, Baocheng; Li, Wenqing

2018-01-01

Biochar application as a soil amendment has been proposed as a strategy to improve soil fertility and increase crop yields. However, the effects of successive biochar applications on cotton yields and nutrient distribution in soil are not well documented. A three-year field study was conducted to investigate the effects of successive biochar applications at different rates on cotton yield and on the soil nutrient distribution in the 0-100 cm soil profile. Biochar was applied at 0, 5, 10, and 20 t ha-1 (expressed as Control, BC5, BC10, and BC20, respectively) for each cotton season, with identical doses of chemical fertilizers. Biochar enhanced the cotton lint yield by 8.0-15.8%, 9.3-13.9%, and 9.2-21.9% in 2013, 2014, and 2015, respectively, and high levels of biochar application achieved high cotton yields each year. Leaching of soil nitrate was reduced, while the pH values, soil organic carbon, total nitrogen (N), and available K content of the 0-20 cm soil layer were increased in 2014 and 2015. However, the changes in the soil available P content were less substantial. This study suggests that successive biochar amendments have the potential to enhance cotton productivity and soil fertility while reducing nitrate leaching.

Impact of hydrochar application on soil nutrient dynamics and plant availability

NASA Astrophysics Data System (ADS)

Bargmann, I.; Greef, J. M.; Kücke, M.

2012-04-01

In order to investigate potentials for the use of HTC-products (hydrochar) in agriculture, the influence of soil application of different hydrochars on soil nutrient dynamics as well as on plant growth and plant nutrient uptake was determined. Hydrochars were produced from sugar beet pulps and brewer's grains by carbonization at 190°C for 4 respectively 12 hours each. Incubation experiments with two soil types showed an increase of soil pH by 0.5 to 2.5 pH units, depending on the amount of hydrochar added and the process conditions (i.e. addition of calcium carbonate during production). The application of HTC to soil decreased the plant available nitrogen to almost zero in the first week after HTC-addition, followed by a slow re-release of nitrate in the following weeks. A similar immobilization of soluble phosphate was observed for one soil type, although to a lower extent. The plant availability of phosphorus in hydrochars and biochars is subject of current trials. Furthermore it is actually investigated to what extend the N immobilization is related to soil microbial activity. Germination tests with barley showed toxic effects of hydrochar application on germination, both by direct contact of grains with HTC as well as by release of gaseous compounds from HTC. Effects differ significantly for different parent materials and pretreatments (washing, drying, storage). The influence of HTC-addition to soil on plant growth and nutrient uptake was investigated in pot experiments with various crop species (barley, phaseolus bean, leek), comparing HTC from different parent materials and process parameters such as carbonization time. With increasing addition of HTC, the N availability was decreased and N contents in the plant were significantly lower compared with the untreated control. The plant growth response was different for each tested crop. On barley, leaf tip necroses were observed, but not on phaseolus. Biomass yield of barley and beans was generally increased by HTC application. In contrast, leek biomass production was reduced. Our experiences show that HTC-materials should be incorporated into soils several weeks before planting/sowing, similar as it is widely recommended for straw incorporation. Alternatively, HTC can be pretreated by composting or fermentation with fresh organic material to destroy toxic compounds microbially.

Response-based selection of barley cultivars and legume species for complementarity: Root morphology and exudation in relation to nutrient source.

PubMed

Giles, Courtney D; Brown, Lawrie K; Adu, Michael O; Mezeli, Malika M; Sandral, Graeme A; Simpson, Richard J; Wendler, Renate; Shand, Charles A; Menezes-Blackburn, Daniel; Darch, Tegan; Stutter, Marc I; Lumsdon, David G; Zhang, Hao; Blackwell, Martin S A; Wearing, Catherine; Cooper, Patricia; Haygarth, Philip M; George, Timothy S

2017-02-01

Phosphorus (P) and nitrogen (N) use efficiency may be improved through increased biodiversity in agroecosystems. Phenotypic variation in plants' response to nutrient deficiency may influence positive complementarity in intercropping systems. A multicomponent screening approach was used to assess the influence of P supply and N source on the phenotypic plasticity of nutrient foraging traits in barley (H. vulgare L.) and legume species. Root morphology and exudation were determined in six plant nutrient treatments. A clear divergence in the response of barley and legumes to the nutrient treatments was observed. Root morphology varied most among legumes, whereas exudate citrate and phytase activity were most variable in barley. Changes in root morphology were minimized in plants provided with ammonium in comparison to nitrate but increased under P deficiency. Exudate phytase activity and pH varied with legume species, whereas citrate efflux, specific root length, and root diameter lengths were more variable among barley cultivars. Three legume species and four barley cultivars were identified as the most responsive to P deficiency and the most contrasting of the cultivars and species tested. Phenotypic response to nutrient availability may be a promising approach for the selection of plant combinations for minimal input cropping systems. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Lipid production from tapioca wastewater by culture of Scenedesmus sp. with simultaneous BOD, COD and nitrogen removal

NASA Astrophysics Data System (ADS)

Romaidi; Hasanudin, Muhammad; Kholifah, Khusnul; Maulidiyah, Alik; Putro, Sapto P.; Kikuchi, Akira; Sakaguchi, Toshifumi

2018-05-01

The use of microalgae to produce biodiesel or possibly remove nutrients from industrial wastewater has gained important attention during recent years due to their photosynthetic rate and its versatile nature to grow in various wastewater systems. In this study, a microalgae, Scenedesmus sp., was cultured to enhance the lipid production and nutrients removal from tapioca wastewater sample. To assess lipid production, Scenedesmus sp. was cultured in different concentration of tapioca wastewater sample (from 0 to 100 %), and nutrient removal including BOD, COD, NH4, NO2, NO3 level by Scenedesmus sp. was assessed in 100% of tapioca wastewater culture. After 8 days of culture, it was found out that 50% of tapioca wastewater sample resulted in highest concentration of lipid content than that of the other concentrations. The level of environment indicator as nutrient removal such as BOD, COD, NH4, NO2, NO3 were also decreased up to 74%, 72%, 95%, 91%, and 91%, respectively. The pH condition changed from initial condition acidic (pH: 4) to neutral or basic condition (pH: 7-8) as recommended in wastewater treatment system. This research provided a novel approach and achieved efficient simultaneous lipid production and nutrients removal from tapioca wastewater sample by Scenedesmus’s culture system.

Enrichment of a mixed microbial culture for polyhydroxyalkanoates production: Effect of pH and N and P concentrations.

PubMed

Montiel-Jarillo, Gabriela; Carrera, Julián; Suárez-Ojeda, María Eugenia

2017-04-01

Polyhydroxyalkanoates (PHA) are biopolymers that can be an alternative against conventional plastics. The study reported herein evaluated the enrichment of a mixed microbial culture (MMC) operated under feast/famine regime and different pHs in a sequencing batch reactor (SBR) using acetate as sole carbon source to produce polyhydroxyalkanoates (PHAs). The enrichment step was evaluated at controlled pH of 7.5 and also without pH control (averaged value of 9.0). The acetate uptake rate (-q S ) of both enrichments at the end of the experimental period exhibited similar behaviour being about 0.18CmolAcCmolX -1 h -1 and 0.19CmolAcCmolX -1 h -1 for SBR-A and SBR-B, respectively. However, the PHA-storing capacity of the biomass enriched without pH control was better, exhibiting a maximum PHA content of 36% (gPHAg -1 VSS) with a PHA production rate (q PHA ) of 0.16CmolPHACmolX -1 h -1 . Batch experiments were performed to evaluate PHA-storing capacity of the enriched culture at different pHs and nutrients concentrations. In the pH experiments (without nutrient limitation), it was found that in the absence of controlled pH, the enriched biomass exhibited a PHA content of 44% gPHAg -1 VSS with -q S and PHA to substrate yield (Y PHA/Ac ) of 0.57CmolAcCmolX -1 h -1 and 0.33CmolPHACmolAc -1 , respectively. Regarding the experiments at variable nutrients concentration (pH ranging 8.8 to 9.2), the results indicate that the PHA content in the enriched biomass is significantly higher being around 51% gPHAg -1 VSS under nitrogen limitation. This work demonstrated the feasibility of the enrichment of a MMC with PHA storage ability without pH control. Results also suggest that better PHAs contents and substrate uptake rates are obtained without controlling the pH in the accumulation step. Finally, this work also highlights the importance of understanding the role of nutrients concentration during the accumulation step. Copyright © 2017 Elsevier B.V. All rights reserved.

Seasonal variation of limnological features and trophic state index of two oligotrophic reservoirs of southeast Brazil.

PubMed

Oliveira, S A; Bicudo, C E M

2017-01-01

Limnological features of two reservoirs were studied in dry (August 2013) and rainy (January 2014) periods to evaluate the water quality that supply the city of Guarulhos, southeast Brazil. Water samples were collected in three depths and the following characteristics were measured: alkalinity, dissolved O2, free and total CO2, HCO3, soluble reactive silica, dissolved and total nitrogen and phosphorus, and chlorophyll-a. Water transparency was also measured and temperature, pH and electric conductivity profiles were obtained. Great seasonal and low spatial variability of the water characteristics occurred in the reservoirs. High values of water transparency, free CO2 availability, and low of pH, soluble reactive silica and total and dissolved nutrients values were recorded at the dry period, and different conditions were found at the rainy season. The two reservoirs were characterized by low nutrients, chlorophyll-a and turbidity, and high transparency, these features being typical of oligotrophic systems. The two reservoirs still remain under low anthropogenic impact conditions, and are presently considered reference systems for the SPMR, São Paulo Metropolitan Region. The need for actions that will reduce the input of nutrients from the neighboring cities and the main tributaries of the hydrographic basin is emphasized to maintain the ecological quality of the reservoirs and their reference conditions among the SPRM reservoirs.

Acetone-butanol-ethanol (ABE) fermentation in an immobilized cell trickle bed reactor.

PubMed

Park, C H; Okos, M R; Wankat, P C

1989-06-05

Acetone-butanol-ethanol (ABE) fermentation was successfully carried out in an immobilized cell trickle bed reactor. The reactor was composed of two serial columns packed with Clostridium acetobutylicum ATCC 824 entrapped on the surface of natural sponge segments at a cell loading in the range of 2.03-5.56 g dry cells/g sponge. The average cell loading was 3.58 g dry cells/g sponge. Batch experiments indicated that a critical pH above 4.2 is necessary for the initiation of cell growth. One of the media used during continuous experiments consisted of a salt mixture alone and the other a nutrient medium containing a salt mixture with yeast extract and peptone. Effluent pH was controlled by supplying various fractions of the two different types of media. A nutrient medium fraction above 0.6 was crucial for successful fermentation in a trickle bed reactor. The nutrient medium fraction is the ratio of the volume of the nutrient medium to the total volume of nutrient plus salt medium. Supplying nutrient medium to both columns continuously was an effective way to meet both pH and nutrient requirement. A 257-mL reactor could ferment 45 g/L glucose from an initial concentration of 60 g/L glucose at a rate of 70 mL/h. Butanol, acetone, and ethanol concentrations were 8.82, 5.22, and 1.45 g/L, respectively, with a butanol and total solvent yield of 19.4 and 34.1 wt %. Solvent productivity in an immobilized cell trickle bed reactor was 4.2 g/L h, which was 10 times higher than that obtained in a batch fermentation using free cells and 2.76 times higher than that of an immobilized CSTR. If the nutrient medium fraction was below 0.6 and the pH was below 4.2, the system degenerated. Oxygen also contributed to the system degeneration. Upon degeneration, glucose consumption and solvent yield decreased to 30.9 g/L and 23.0 wt %, respectively. The yield of total liquid product (40.0 wt %) and butanol selectivity (60.0 wt %) remained almost constant. Once the cells were degenerated, they could not be recovered.

The effect of nitrate and phosphate availability on Emiliania huxleyi (NZEH) physiology under different CO2 scenarios.

PubMed

Rouco, Mónica; Branson, Oscar; Lebrato, Mario; Iglesias-Rodríguez, M Débora

2013-01-01

Growth and calcification of the marine coccolithophorid Emiliania huxleyi is affected by ocean acidification and macronutrients limitation and its response varies between strains. Here we investigated the physiological performance of a highly calcified E. huxleyi strain, NZEH, in a multiparametric experiment. Cells were exposed to different CO2 levels (ranging from 250 to 1314 μatm) under three nutrient conditions [nutrient replete (R), nitrate limited (-N), and phosphate limited (-P)]. We focused on calcite and organic carbon quotas and on nitrate and phosphate utilization by analyzing the activity of nitrate reductase (NRase) and alkaline phosphatase (APase), respectively. Particulate inorganic (PIC) and organic (POC) carbon quotas increased with increasing CO2 under R conditions but a different pattern was observed under nutrient limitation. The PIC:POC ratio decreased with increasing CO2 in nutrient limited cultures. Coccolith length increased with CO2 under all nutrient conditions but the coccosphere volume varied depending on the nutrient treatment. Maximum APase activity was found at 561 μatm of CO2 (pH 7.92) in -P cultures and in R conditions, NRase activity increased linearly with CO2. These results suggest that E. huxleyi's competitive ability for nutrient uptake might be altered in future high-CO2 oceans. The combined dataset will be useful in model parameterizations of the carbon cycle and ocean acidification.

The Growth Advantage in Stationary-Phase Phenotype Conferred by rpoS Mutations Is Dependent on the pH and Nutrient Environment

PubMed Central

Farrell, Michael J.; Finkel, Steven E.

2003-01-01

Escherichia coli cells that are aged in batch culture display an increased fitness referred to as the growth advantage in stationary phase, or GASP, phenotype. A common early adaptation to this culture environment is a mutant rpoS allele, such as rpoS819, that results in attenuated RpoS activity. However, it is important to note that during long-term batch culture, environmental conditions are in flux. To date, most studies of the GASP phenotype have focused on identifying alleles that render an advantage in a specific environment, Luria-Bertani broth (LB) batch culture. To determine what role environmental conditions play in rendering relative fitness advantages to E. coli cells carrying either the wild-type or rpoS819 alleles, we performed competitions under a variety of culture conditions in which either the available nutrients, the pH, or both were manipulated. In LB medium, we found that while the rpoS819 allele confers a strong competitive fitness advantage at basic pH, it confers a reduced advantage under neutral conditions, and it is disadvantageous under acidic conditions. Similar results were found using other media. rpoS819 conferred its greatest advantage in basic minimal medium in which either glucose or Casamino Acids were the sole source of carbon and energy. In acidic medium supplemented with either Casamino Acids or glucose, the wild-type allele conferred a slight advantage. In addition, populations were dynamic under all pH conditions tested, with neither the wild-type nor mutant rpoS alleles sweeping a culture. We also found that the strength of the fitness advantage gained during a 10-day incubation is pH dependent. PMID:14645263

Long-term dynamics of soil chemical properties after a prescribed fire in a Mediterranean forest (Montgrí Massif, Catalonia, Spain).

PubMed

Alcañiz, M; Outeiro, L; Francos, M; Farguell, J; Úbeda, X

2016-12-01

This study examines the effects of a prescribed fire on soil chemical properties in the Montgrí Massif (Girona, Spain). The prescribed forest fire was conducted in 2006 to reduce understory vegetation and so prevent potential severe wildfires. Soil was sampled at a depth of 0-5cm at 42 sampling points on four separate occasions: prior to the event, immediately after, one year after and nine years after. The parameters studied were pH, electrical conductivity (EC), total carbon (C), total nitrogen (N), available phosphorus (P), potassium (K + ), calcium (Ca 2+ ) and magnesium (Mg 2+ ). All parameters (except pH) increased significantly immediately after the fire. One year after burning, some chemical parameters - namely, EC, available P and K + - had returned to their initial, or even lower, values; while others - pH and total C - continued to rise. Total N, Ca 2+ and Mg 2+ levels had fallen one year after the fire, but levels were still higher than those prior to the event. Nine years after the fire, pH, total C, total N and available P are significantly lower than pre-fire values and nutrients concentrations are now higher than at the outset but without statistical significance. The soil system, therefore, is still far from being recovered nine years later. Copyright © 2016 Elsevier B.V. All rights reserved.

Simulated effects of acidic solutions on element dynamics in monsoon evergreen broad-leaved forest at Dinghushan, China. Part 1: dynamics of K, Na, Ca, Mg and P.

PubMed

Liu, Juxiu; Zhou, Guoyi; Zhang, Deqiang

2007-03-01

Acid deposition has become a concern in south China in recent years. This phenomenon has increased to a dramatic extent with the large use of cars and coal-fueled power plants. As a consequence, soils are becoming acidified and their element dynamics will change. A decrease in the nutrient availability will lead to slower plant growth and maybe to a change in the forest type with current species being replaced by new ones with less nutrient requirements. Because of these reasons, it is important to understand how the dynamics of elements will change and what mechanism is part of the process. This knowledge is important for modeling the acidification process and either finding ways to counter it or to predict its consequences. The primary purpose of this study was to provide information about how the dynamics of K, Na, Ca, Mg and P are affected by acid deposition in a typical forest in southern China. Experimental soils and saplings were collected directly from the monsoon evergreen broad-leaved forest in Dinghushan. All saplings were transplanted individually into ceramic pots in August 2000 and placed in an open area near their origin site. Pot soils were treated weekly from October 2000 to July 2002 with an acidic solution at pH 3.05, pH 3.52, pH 4.00 or pH 4.40, or with tap water as a control. The concentrations of SO4(2-), NO3-, K+, Na+, Ca2+, Mg2+ and available P and the pH were measured in soil and leachate samples taken at different times. The sapling leaves were collected and their element concentrations were measured at the end of the experiment. Concentrations of soil exchangeable Ca and Mg decreased quickly over time, although only Ca showed changes with the acidic solution treatment and soil exchangeable K was stable because of soil weathering. Leaching of K, Mg and Ca was dependent upon the treatment acidity. Soil available P decreased slowly without any correlation with the acidity of the treatment. All the NO3- added by the treatment was taken up by the plants, but the SO4(2-) added accumulated in the soil. Amongst the plant species, Schima superba was little affected by the treatment, the leaf P content was affected in Acmena acuminatissima plants and Cryptocarya concinna was the most susceptible species to soil acidification, with a marked decrease of, the leaf K, Ca and Mg concentrations when the treatment acidity increased. Simulated acid deposition affected the dynamics of K, Ca and Mg in the monsoon evergreen broad-leaved forest. The dynamics of Ca in the soil and of K, Mg and Ca in the soil leachates were affected by the acidic solution treatment. If such a soil acidification occurs, Cryptocarya concinna will be amongst the first affected species, but Schima superba will be able to sustain a good growth and mineral nutrition. Acid deposition will lead to imbalance the nutrient elements in the evergreen broad-leaved forest because of accelerated leaching losses of soil exchangeable Ca and Mg. Measures should be developed to slow down soil acidification or nutrient decrease.

The effects of CO₂ addition along a pH gradient on wastewater microalgal photo-physiology, biomass production and nutrient removal.

PubMed

Sutherland, Donna L; Howard-Williams, Clive; Turnbull, Matthew H; Broady, Paul A; Craggs, Rupert J

2015-03-01

Carbon limitation in domestic wastewater high rate algal ponds is thought to constrain microalgal photo-physiology and productivity, particularly in summer. This paper investigates the effects of CO₂ addition along a pH gradient on the performance of wastewater microalgae in high rate algal mesocosms. Performance was measured in terms of light absorption, electron transport rate, photosynthetic efficiency, biomass production and nutrient removal efficiency. Light absorption by the microalgae increased by up to 128% with increasing CO₂ supply, while a reduction in the package effect meant that there was less internal self-shading thereby increasing the efficiency of light absorption. CO₂ augmentation increased the maximum rate of both electron transport and photosynthesis by up to 256%. This led to increased biomass, with the highest yield occurring at the highest dissolved inorganic carbon/lowest pH combination tested (pH 6.5), with a doubling of chlorophyll-a (Chl-a) biomass while total microalgal biovolume increased by 660% in Micractinium bornhemiense and by 260% in Pediastrum boryanum dominated cultures. Increased microalgal biomass did not off-set the reduction in ammonia volatilisation in the control and overall nutrient removal was lower with CO₂ than without. Microalgal nutrient removal efficiency decreased as pH decreased and may have been related to decreased Chl-a per cell. This experiment demonstrated that CO₂ augmentation increased microalgal biomass in two distinct communities, however, care must be taken when interpreting results from standard biomass measurements with respect to CO₂ augmentation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Enzyme Sorption onto Soil and Biocarbon Amendments Alters Catalytic Capacity and Depends on the Specific Protein and pH

NASA Astrophysics Data System (ADS)

Foster, E.; Fogle, E. J.; Cotrufo, M. F.

2017-12-01

Enzymes catalyze biogeochemical reactions in soils and play a key role in nutrient cycling in agricultural systems. Often, to increase soil nutrients, agricultural managers add organic amendments and have recently experimented with charcoal-like biocarbon products. These amendments can enhance soil water and nutrient holding capacity through increasing porosity. However, the large surface area of the biocarbon has the potential to sorb nutrients and other organic molecules. Does the biocarbon decrease nutrient cycling through sorption of enzymes? In a laboratory setting, we compared the interaction of two purified enzymes β-glucosidase and acid phosphatase with a sandy clay loam and two biocarbons. We quantified the sorbed enzymes at three different pHs using a Bradford protein assay and then measured the activity of the sorbed enzyme via high-throughput fluorometric analysis. Both sorption and activity depended upon the solid phase, pH, and specific enzyme. Overall the high surface area biocarbon impacted the catalytic capacity of the enzymes more than the loam soil, which may have implications for soil nutrient management with these organic amendments.

Thermally Induced Encapsulation of Food Nutrients into Phytoferritin through the Flexible Channels without Additives.

PubMed

Yang, Rui; Tian, Jing; Liu, Yuqian; Yang, Zhiying; Wu, Dandan; Zhou, Zhongkai

2017-11-22

The cavity of phytoferritin provides a nanospace to encapsulate and deliver food nutrient molecules. However, tranditional methods to prepare the ferritin-nutrient complexes must undergo acid/alkaline conditions or apply additives. In this work, we provide a novel guideline that thermal treatment at 60 °C can expand ferritin channels by uncoiling the surrounding α-helix. Upon reduction of the temperature to 20 °C, food nutrient rutin can be encapsulated in apo-soybean seed ferritin (apoSSF) at pH 7.0 through channels without disassembly of the protein cage and with no addition of additives. Results indicated that one apoSSF could encapsulate about 10.5 molecules of rutin, with an encapsulation ratio of 8.08% (w/w). In addition, the resulting rutin-loaded SSF complexes were monodispersed in a size of 12 nm in aqueous solution. This work provides a novel pathway for the encapsulation of food nutrient molecules into the nanocavity of ferritin under a neutral pH condition induced by thermal treatment.

On the Response of pH to Inorganic Nutrient Enrichment in Well-Mixed Coastal Marine Waters

EPA Science Inventory

Recent concerns about declining pH in the surface ocean in response to anthropogenic increases of CO2 in the atmosphere have raised the question of how this declining baseline of oceanic pH might interact with the much larger diel and seasonal variations of pH in coastal marine e...

Selective uptake of major and trace elements in Erica andevalensis, an endemic species to extreme habitats in the Iberian Pyrite Belt.

PubMed

Monaci, Fabrizio; Leidi, Eduardo O; Dolores, Mingorance Maria; Valdés, Benito Oliva; Rossini, Sabina Sabina; Bargagli, Roberto

2011-01-01

To assess the ecophysiological traits and the phytoremediation potential of the endemic heather Erica andevalensis, we determined the concentrations of major and trace elements in different plant parts and in rizosphere soils from Riotinto mining district (Huelva, Spain). The results showed that E. andevalensis may grow on substrates with very high As, Cu, Fe and Pb concentrations (up to 4114, 1050, 71900 and 15614 microg/g dry weight, respectively), very low availability of macro- and micronutrients and with pH values ranging from 3.3 to 4.9. In these harsh edaphic conditions E. andevalensis selectively absorbed and translocated essential nutrients and excludes potentially phytotoxic elements, which were accumulated in the root epidermis. The concentrations of major and trace elements in E. andevalensis aerial parts from the Riotinto mining district were in the normal range for plants; likewise other Erica species it accumulated Mn and only in a very polluted site we measured leaf concentrations of As and Pb within the excessive or toxic limits for plants. Differently from previous studies, which emphasized the soil pH and bioavailability of phytotoxic elements as the main stress factors, this study showed that in the Riotinto region, E. andevalensis can tolerate wide range of pH and toxic element concentrations; the harshest environments colonized by monospecific patches of this species were characterized above all by very low availability of nutrients. The extraordinary capability to adapt to these extreme habitats made E. andevalensis a priority species to promote the phytostabilization and the development of a self-sustaining vegetative cover on Riotinto mine tailings.

Effects of five years of frequent N additions, with or without acidity, on the growth and below-ground dynamics of a young Sitka spruce stand growing on an acid peat: implications for sustainability

NASA Astrophysics Data System (ADS)

Stutter, M. I.; Alam, M. S.; Langan, S. J.; Woodin, S. J.; Smart, R. P.; Cresser, M. S.

2004-06-01

An experiment comparing effects of sulphuric acid and reduced N deposition on soil water quality and on chemical and physical growth indicators for forest ecosystems is described. Six H2SO4 and (NH4)2SO4 treatment loads, from 0 - 44 and 0 - 25 kmolc ha-1 yr-1, respectively, were applied to outdoor microcosms of Pinus sylvestris seedlings in 3 acid to intermediate upland soils (calc-silicate, quartzite and granite) for 2 years. Different soil types responded similarly to H2SO4 loads, resulting in decreased leachate pH, but differently to reduced N inputs. In microcosms of calc-silicate soil, nitrification of NH4 resulted in lower pH and higher cation leaching than in acid treatments. By contrast, in quartzite and granite soils, (NH4)2SO4 promoted direct cation leaching, although leachate pH increased. The results highlighted the importance of soil composition on the nature of the cations leached, the SO4 adsorption capacities and microbial N transformations. Greater seedling growth on calc-silicate soils under both treatment types was related to sustained nutrient availability. Reductions in foliar P and Mg with higher N treatments were observed for seedlings in the calc-silicate soil. There were few treatment effects on quartzite and granite microcosm tree seedlings since P limitation precluded seedling growth responses to treatments. Hence, any benefits of N deposition to seedlings on quartzite and granite soils appeared limited by availability of co-nutrients, exacerbated by rapid depletion of soil exchangeable base cations.

Superdosing phytase reduces real-time gastric pH in broilers and weaned piglets.

PubMed

Lee, S A; Dunne, J; Febery, E; Wilcock, P; Mottram, T; Bedford, M R

2018-06-01

1. The current study was conducted to investigate the effect of high phytase doses on growth performance and real-time gastric pH measurements in broiler chickens and pigs. 2. In the first experiment, 576 male Ross 308 broilers were fed in two phases (0-21 and 21-42 d) with 4 treatment groups, with diets meeting nutrient requirements containing 0, 500, 1500 or 2500 FTU/kg phytase. In the second, 64 Landrace weaners were fed on diets meeting nutrient requirements with or without phytase (0 or 2500 FTU/kg) in two phases (0-21 and 21-42 d). Heidelberg pH capsules were administered to 7 broilers and approximately 13 pigs per treatment group, pre- and post-phase change, with readings monitored over several hours. 3. Addition of phytase into an adequate Ca and P diet had no significant effect on broiler performance although phytase tended (P < 0.07) to improve feed conversion in pigs over the entire experimental period. Real-time pH capsule readings in broilers demonstrated an increase (P < 0.05) in gizzard pH when phytase was dosed at 500 or 1500 FTU/kg, while higher doses of 2500 FTU/kg phytase lowered pH to a level comparable to control birds. Gastric pH increased (P < 0.01) when animals were exposed to dietary phase change, signifying a potential challenge period for nutrient digestibility. However, pigs fed 2500 FTU/kg were able to maintain gastric pH levels through diet phase change. In contrast, spear-tip probe measurements showed no treatment effect on gastric pH. 4. These findings demonstrate dietary manipulation of gastric pH and the value of real-time pH capsule technology as a means of determining phytase dose response.

Effect of polymers in solution culture on growth and mineral composition of tomatoes. [Lycopersicon esculentum

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

Wallace, A.

Tomato (Lycopersicon esculentum Mill. cv. Tropic) plants were grown for 26 days from transplanting in full nutrient solution with and without polymers in nutrient solution at two different pH values. An aninoic polyacrylamide and a polysaccharide (from guar bean) each at 100 mg L/sup -1/ in solution slightly improved yields at both pH values. A cationic polymer at the same concentration decreased yields. There were no apparent nutritional reasons for the effects. 1 table.

Proton Transport and pH Control in Fungi.

PubMed

Kane, Patricia M

2016-01-01

Despite diverse and changing extracellular environments, fungi maintain a relatively constant cytosolic pH and numerous organelles of distinct lumenal pH. Key players in fungal pH control are V-ATPases and the P-type proton pump Pma1. These two proton pumps act in concert with a large array of other transporters and are highly regulated. The activities of Pma1 and the V-ATPase are coordinated under some conditions, suggesting that pH in the cytosol and organelles is not controlled independently. Genomic studies, particularly in the highly tractable S. cerevisiae, are beginning to provide a systems-level view of pH control, including transcriptional responses to acid or alkaline ambient pH and definition of the full set of regulators required to maintain pH homeostasis. Genetically encoded pH sensors have provided new insights into localized mechanisms of pH control, as well as highlighting the dynamic nature of pH responses to the extracellular environment. Recent studies indicate that cellular pH plays a genuine signaling role that connects nutrient availability and growth rate through a number of mechanisms. Many of the pH control mechanisms found in S. cerevisiae are shared with other fungi, with adaptations for their individual physiological contexts. Fungi deploy certain proton transport and pH control mechanisms not shared with other eukaryotes; these regulators of cellular pH are potential antifungal targets. This review describes current and emerging knowledge proton transport and pH control mechanisms in S. cerevisiae and briefly discusses how these mechanisms vary among fungi.

Proton Transport and pH Control in Fungi

PubMed Central

Kane, Patricia M.

2018-01-01

Despite diverse and changing extracellular environments, fungi maintain a relatively constant cytosolic pH and numerous organelles of distinct lumenal pH. Key players in fungal pH control are V-ATPases and the P-type proton pump Pma1. These two proton pumps act in concert with a large array of other transporters and are highly regulated. The activities of Pma1 and the V-ATPaseare coordinated under some conditions, suggesting that pH in the cytosol and organelles is not controlled independently. Genomic studies, particularly in the highly tractable S. cerevisiae, are beginning to provide a systems-level view of pH control, including transcriptional responses to acid or alkaline ambient pH and definition of the full set of regulators required to maintain pH homeostasis. Genetically encoded pH sensors have provided new insights into localized mechanisms of pH control, as well as highlighting the dynamic nature of pH responses to the extracellular environment. Recent studies indicate that cellular pH plays a genuine signaling role that connects nutrient availability and growth rate through a number of mechanisms. Many of the pH control mechanisms found in S. cerevisiae are shared with other fungi, with adaptations for their individual physiological contexts. Fungi deploy certain proton transport and pH control mechanisms not shared with other eukaryotes; these regulators of cellular pH are potential antifungal targets. This re view describes current and emerging knowledge proton transport and pH control mechanisms in S. cerevisiae and briefly discusses how these mechanisms vary among fungi. PMID:26721270

[Fine root dynamics and its relationship with soil fertility in tropical rainforests of Chocó].

PubMed

Quinto, Harley; Caicedo, Haylin; Thelis Perez, May; Moreno, Flavio

2016-12-01

The fine roots play an important role in the acquisition of water and minerals from the soil, the global carbon balance and mitigation of climate change. The dynamics (productivity and turnover) of fine roots is essential for nutrient cycling and carbon balance of forest ecosystems. The availability of soil water and nutrients has significantly determined the productivity and turnover of fine roots. It has been hypothesized that fine roots dynamics increases with the availability of soil resources in tropical forest ecosystems. To test this hypothesis in tropical rainforests of Chocó (ecosystems with the highest rainfall in the world), five one-ha permanent plots were established in the localities of Opogodó and Pacurita, where the productivity and turnover of fine roots were measured at 0-10 cm and 10-20 cm depth. The measurement of the fine root production was realized by the Ingrowth core method. The fine root turnover was measured like fine roots production divided mean annual biomass. In addition, soil fertility parameters (pH, nutrients, and texture) were measured and their association with productivity and turnover of fine roots was evaluated. It was found that the sites had nutrient-poor soils. The localities also differ in soil; Opogodó has sandy soils and flat topography, and Pacurita has clay soils, rich in aluminum and mountainous topography. In Opogodó fine root production was 6.50 ± 2.62 t/ha.yr (mean ± SD). In Pacurita, fine root production was 3.61 ± 0.88 t/ha.yr. Also in Opogodó, the fine root turnover was higher than in Pacurita (1.17 /y and 0.62 /y, respectively). Fine root turnover and production in the upper soil layers (10 cm upper soil) was considerably higher. Productivity and turnover of fine roots showed positive correlation with pH and contents of organic matter, total N, K, Mg, and sand; whereas correlations were negative with ECEC and contents of Al, silt, and clay. The percentage of sand was the parameter that best explained the variations of fine root production. The fine root turnover was negatively explained by soil Al availability. Results suggested the increase of fine root dynamics with soil fertility at a local scale, which also indicates that under the oligotrophic conditions of soils in tropical rainforests, fine roots tend to proliferate rapidly in small patches of soil rich in sand and nutrients.

Stimulated Bacterial Growth under Elevated pCO2: Results from an Off-Shore Mesocosm Study

PubMed Central

Endres, Sonja; Galgani, Luisa; Riebesell, Ulf; Schulz, Kai-Georg; Engel, Anja

2014-01-01

Marine bacteria are the main consumers of freshly produced organic matter. Many enzymatic processes involved in the bacterial digestion of organic compounds were shown to be pH sensitive in previous studies. Due to the continuous rise in atmospheric CO2 concentration, seawater pH is presently decreasing at a rate unprecedented during the last 300 million years but the consequences for microbial physiology, organic matter cycling and marine biogeochemistry are still unresolved. We studied the effects of elevated seawater pCO2 on a natural plankton community during a large-scale mesocosm study in a Norwegian fjord. Nine Kiel Off-Shore Mesocosms for Future Ocean Simulations (KOSMOS) were adjusted to different pCO2 levels ranging initially from ca. 280 to 3000 µatm and sampled every second day for 34 days. The first phytoplankton bloom developed around day 5. On day 14, inorganic nutrients were added to the enclosed, nutrient-poor waters to stimulate a second phytoplankton bloom, which occurred around day 20. Our results indicate that marine bacteria benefit directly and indirectly from decreasing seawater pH. During the first phytoplankton bloom, 5–10% more transparent exopolymer particles were formed in the high pCO2 mesocosms. Simultaneously, the efficiency of the protein-degrading enzyme leucine aminopeptidase increased with decreasing pH resulting in up to three times higher values in the highest pCO2/lowest pH mesocosm compared to the controls. In general, total and cell-specific aminopeptidase activities were elevated under low pH conditions. The combination of enhanced enzymatic hydrolysis of organic matter and increased availability of gel particles as substrate supported up to 28% higher bacterial abundance in the high pCO2 treatments. We conclude that ocean acidification has the potential to stimulate the bacterial community and facilitate the microbial recycling of freshly produced organic matter, thus strengthening the role of the microbial loop in the surface ocean. PMID:24941307

Impacts of industrial waste resources on maize (Zea mays L.) growth, yield, nutrients uptake and soil properties.

PubMed

Singh, Satnam; Young, Li-Sen; Shen, Fo-Ting; Young, Chiu-Chung

2014-10-01

Discharging untreated highly acidic (pH<4.0), organic and nutrients rich monosodium glutamate wastewater (MW), and highly alkaline (pH>10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5±0.1) with PW and lime (treatments represented as MW+PW and MW+Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha(-1). Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear(-1) and 100-kernel weight were higher in MW+Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW+Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW+PW. The MW+PW and MW+Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances. Copyright © 2014. Published by Elsevier Ltd.

mTor Regulates Lysosomal ATP-sensitive Two-Pore Na+ Channel to Adapt to Metabolic State

PubMed Central

Navarro, Betsy; Seo, Young-jun; Aranda, Kimberly; Shi, Lucy; Battaglia-Hsu, Shyuefang; Nissim, Itzhak; Clapham, David E.; Ren, Dejian

2014-01-01

SUMMARY Survival in the wild requires organismal adaptations to the availability of nutrients. Endosomes and lysosomes are key intracellular organelles that couple nutrition and metabolic status to cellular responses, but how they detect cytosolic ATP levels is not well understood. Here we identify an endolysosomal ATP-sensitive Na+ channel (lysoNaATP). The channel is a complex formed by Two-Pore Channels (TPC1 and TPC2), ion channels previously thought to be gated by nicotinic acid adenine dinucleotide phosphate (NAADP), and the mammalian target of rapamycin (mTOR). The channel complex detects nutrient status, becomes constitutively open upon nutrient removal and mTOR translocation off the lysosomal membrane, and controls the lysosome's membrane potential, pH stability, and the amino acid homeostasis. Mutant mice lacking lysoNaATP have much reduced exercise endurance after fasting. Thus, TPCs are a new ion channel family that couple the cell's metabolic state to endolysosomal function and are crucial for physical endurance during food restriction. PMID:23394946

Nutrient recovery from apple pomace waste by vermicomposting technology.

PubMed

Hanc, Ales; Chadimova, Zuzana

2014-09-01

The present work was focused on vermicomposting apple pomace waste and its mixtures with straw in volume proportions of 25%, 50%, and 75%. The feasibility was evaluated on the basis of agrochemical properties and earthworm biomass. Vermicomposting was able to reduce the weight and volume of the feedstock by 65% and 85%, respectively. The resulting vermicomposts were characterized by slightly acidic to neutral pH (5.9-6.9), and optimal EC (1.6-4.4mS/cm) and C:N ratios (13-14). The total content of nutrients increased during vermicomposting for all of the treatments with the following average final values: N=2.8%, P=0.85%, K=2.3%, and Mg=0.38%. The addition of straw to apple pomace did not enhance earthworm biomass, but did increase the available content of nutrients during vermicomposting. The data reveals that vermicomposting is a suitable technology for the decomposition of apple pomace waste into a value added product. Copyright © 2014 Elsevier Ltd. All rights reserved.

Changes of parameters during composting of bio-waste collected over four seasons.

PubMed

Hanc, Ales; Ochecova, Pavla; Vasak, Filip

2017-07-01

This study investigated the evolution of several main parameters during the composting of separately collected household bio-waste originating from urban settlements (U-bio-waste) and family houses (F-bio-waste) from four climate seasons. When comparing both types of composts, U-bio-waste compost contained a higher amount of nutrients, however F-bio-waste compost was characterized by greater yield, greater availability of phosphorus and magnesium, and faster stability. In terms of seasons, compost from bio-waste collected in spring contained the highest amount of nutrients, reflecting the high content of nutrients in plant feedstock. Dissolved organic carbon and pH in U- and F-bio-waste compost, respectively, frequently showed close relationships with other parameters. The seasonal variations of most of the parameters in the composts were found to be lower compared to the variations observed in the feedstocks. The greatest seasonal variation was found in nitrate nitrogen, which is the reason for the more frequent analysis of this parameter.

[Responses of rhizosphere nitrogen and phosphorus transformations to different acid rain intensities in a hilly red soil tea plantation].

PubMed

Chen, Xi; Chen, Fu-sheng; Ye, Su-qiong; Yu, Su-qin; Fang, Xiang-min; Hu, Xiao-fei

2015-01-01

Tea (Camellia sinensis) plantation in hilly red soil region has been long impacted by acid deposition, however its effects on nitrogen (N) and phosphorus (P) transformations in rhizosphere soils remain unclear. A 25-year old tea plantation in a typical hilly red soil region was selected for an in situ simulation experiment treated by pH 4.5, pH 3.5, pH 2.5 and control. Rhizosihere and bulk soils were collected in the third year from the simulated acid deposition experiment. Soil mineral N, available P contents and major enzyme activities were analyzed using the chemical extraction and biochemical methods, and N and P mineralization rates were estimated using the indoor aerobic incubation methods. Our results showed that compared to the control, the treatments of pH 4.5, pH 3.5 and pH 2.5, respectively decreased 7.1%, 42.1% and 49.9% NO3(-)-N, 6.4%, 35.9% and 40.3% mineral N, 10.5%, 41.1% and 46.9% available P, 18.7%, 30.1% and 44.7% ammonification rate, 3.6%, 12.7% and 38.8% net N-mineralization rate, and 31.5%, 41.8% and 63.0% P mineralization rate in rhizosphere soils; however, among the 4 treatments, rhizosphere soil nitrification rate was not significantly different, the rhizosphere soil urease and acid phosphatase activities generally increased with the increasing intensity of acid rain (P<0.05). In bulk soil, compared with the control, the treatments of pH 4.5, pH 3.5 and pH 2.5 did not cause significant changes in NO3(-)-N, mineral N, available P as well as in the rates of nitrification, ammonification, net N-mineralization and P mineralization. With increasing the acid intensity, the rhizosphere effects of NH4+-N, NO3(-)-N, mineral N, ammonification and net N-mineralization rates were altered from positive to negative effects, those of urease and acid phosphatease showed the opposite trends, those of available P and P mineralization were negative and that of nitrification was positive. In sum, prolonged elevated acid rain could reduce N and P transformation rates, decrease their availability, alter their rhizosphere effects, and have impact on nutrient cycling in tea plantation.

Root-zone acidity affects relative uptake of nitrate and ammonium from mixed nitrogen sources

NASA Technical Reports Server (NTRS)

Vessey, J. K.; Henry, L. T.; Chaillou, S.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

1990-01-01

Soybean plants (Glycine max [L.] Merr. cv Ransom) were grown for 21 days on 4 sources of N (1.0 mM NO3-, 0.67 mM NO3- plus 0.33 mM NH4+, 0.33 mM NO3- plus 0.67 mM NH4+, and 1.0 mM NH4+) in hydroponic culture with the acidity of the nutrient solution controlled at pH 6.0, 5.5, 5.0, and 4.5. Dry matter and total N accumulation of the plants was not significantly affected by N-source at any of the pH levels except for decreases in these parameters in plants supplied solely with NH4+ at pH 4.5. Shoot-to-root ratios increased in plants which had an increased proportion [correction of proporiton] of NH4(+)-N in their nutrient solutions at all levels of root-zone pH. Uptake of NO3- and NH4+ was monitored daily by ion chromatography as depletion of these ions from the replenished hydroponic solutions. At all pH levels the proportion of either ion that was absorbed increased as the ratio of that ion increased in the nutrient solution. In plants which were supplied with sources of NO3- plus NH4+, NH4+ was absorbed at a ratio of 2:1 over NO3- at pH 6.0. As the pH of the root-zone declined, however, NH4+ uptake decreased and NO3- uptake increased. Thus, the NH4+ to NO3- uptake ratio declined with decreases in root-zone pH. The data indicate a negative effect of declining root-zone pH on NH4+ uptake and supports a hypothesis that the inhibition of growth of plants dependent on NH4(+)-N at low pH is due to a decline in NH4+ uptake and a consequential limitation of growth by N stress.

Tide- and rainfall-induced variations of physical and chemical parameters in a mangrove-depleted estuary of East Hainan (South China Sea).

PubMed

Krumme, Uwe; Herbeck, Lucia S; Wang, Tianci

2012-12-01

The estuarine dynamics favoring the coexistence of mangroves, seagrass and corals at small river mouths are often poorly understood. We characterize the tidal, day/night and rainfall-induced short-term dynamics in salinity, pH, dissolved oxygen (DO), chlorophyll a (chl a), total suspended matter (TSM), water transparency, surface currents and dissolved nutrients (NO(x)(-), NH(4)(+), PO(4)(3)(-), Si(OH)(4)) of the Wenchang/Wenjiao Estuary (East Hainan, tropical China). Samples were taken at three fixed sites along the estuary during 24 h spring tide cycles in different seasons. Salinity, DO, water transparency and pH generally increased seawards while nutrients decreased. All parameters varied with the tidal cycle, partially in interaction with the diel cycle. Nutrients, chl a and TSM usually fluctuated inversely with water level. Stratification was strong. Inflowing bottom water was of higher salinity, DO and pH and lower temperature and nutrient concentrations than the surface water. Tidal mixing provided regular ventilation of the estuary and limited eutrophication effects of nutrients from aquaculture, agriculture and urban effluents. Under dry weather conditions, the brackish-water lagoon functioned as a sink of nutrients due to efficient uptake by phytoplankton. Presently, the runoff from common intense rains in the watershed affects the estuary with little time delay due to terrestrial deforestation, channelization and loss of mangrove area. The frequency, strength and duration of intermittent estuarization of the back-reef areas have likely increased in the past and deteriorate present seagrass and coral health. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biochar derived from corn straw affected availability and distribution of soil nutrients and cotton yield

PubMed Central

Tian, Xiaofei; Zhang, Min; Wan, Yongshan; Xie, Zhihua; Chen, Baocheng; Li, Wenqing

2018-01-01

Biochar application as a soil amendment has been proposed as a strategy to improve soil fertility and increase crop yields. However, the effects of successive biochar applications on cotton yields and nutrient distribution in soil are not well documented. A three-year field study was conducted to investigate the effects of successive biochar applications at different rates on cotton yield and on the soil nutrient distribution in the 0–100 cm soil profile. Biochar was applied at 0, 5, 10, and 20 t ha-1 (expressed as Control, BC5, BC10, and BC20, respectively) for each cotton season, with identical doses of chemical fertilizers. Biochar enhanced the cotton lint yield by 8.0–15.8%, 9.3–13.9%, and 9.2–21.9% in 2013, 2014, and 2015, respectively, and high levels of biochar application achieved high cotton yields each year. Leaching of soil nitrate was reduced, while the pH values, soil organic carbon, total nitrogen (N), and available K content of the 0–20 cm soil layer were increased in 2014 and 2015. However, the changes in the soil available P content were less substantial. This study suggests that successive biochar amendments have the potential to enhance cotton productivity and soil fertility while reducing nitrate leaching. PMID:29324750

Role of microbial inoculation and industrial by-product phosphogypsum in growth and nutrient uptake of maize (Zea mays L.) grown in calcareous soil.

PubMed

Al-Enazy, Abdul-Aziz R; Al-Oud, Saud S; Al-Barakah, Fahad N; Usman, Adel Ra

2017-08-01

Alkaline soils with high calcium carbonate and low organic matter are deficient in plant nutrient availability. Use of organic and bio-fertilizers has been suggested to improve their properties. Therefore, a greenhouse experiment was conducted to evaluate the integrative role of phosphogypsum (PG; added at 0.0, 10, 30, and 50 g PG kg -1 ), cow manure (CM; added at 50 g kg -1 ) and mixed microbial inoculation (Incl.; Azotobacter chroococcum, and phosphate-solubilizing bacteria Bacillus megaterium var. phosphaticum and Pseudomonas fluorescens) on growth and nutrients (N, P, K, Fe, Mn, Zn and Cu) uptake of maize (Zea mays L.) in calcareous soil. Treatment effects on soil chemical and biological properties and the Cd and Pb availability to maize plants were also investigated. Applying PG decreased soil pH. The soil available P increased when soil was inoculated and/or treated with CM, especially with PG. The total microbial count and dehydrogenase activity were enhanced with PG+CM+Incl. Inoculated soils treated with PG showed significant increases in NPK uptake and maize plant growth. However, the most investigated treatments showed significant decreases in shoot micronutrients. Cd and Pb were not detected in maize shoots. Applying PG with microbial inoculation improved macronutrient uptake and plant growth. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Development of an Advanced Respirometer for Experimental Studies of Benthic Rate Processes

NASA Astrophysics Data System (ADS)

Barry, J. P.; Buck, K. R.; Okuda, C.; Risi, M.; Parker, M.; Levesque, C.

2005-05-01

Rates of carbon remineralization and nutrient cycling by seafloor biotic assemblages are influenced by the availability of organic material, temperature, and oxygen availability, among other factors. The relative importance of various factors in controlling carbon cycling by the sediment community is poorly constrained, in part by technological limits on experiments that evaluate independently the effects of these factors. We have developed an advanced respiration chamber system capable of repeated rate measurements during a single deployment, with added capabilities for manipulating conditions within replicate chambers to test hypotheses concerning biogeochemical cycling by the benthos. The ROV-deployed respiration system has 12 syringes for tracer injection or sample withdrawal from 3 respiration chambers, pH, oxygen, and temperature sensors, stirring paddles, and a recirculation pump. The pump system is used to flush each chamber at preprogrammed intervals or oxygen tensions. Areas of investigation that are enabled by the system include the effects various factors on benthic oxygen consumptions (e.g. hypercapnia (elevated CO2), acidosis, ambient oxygen availability, temperature, organic carbon availability), rates of nutrient regeneration by the benthos in response to organic enrichments (labile and refractory organic carbon), time lags in carbon uptake and trophic pathways in responses to organic enrichment.

Rapid releases of metal salts and nutrients following the deposition of volcanic ash into aqueous environments

NASA Astrophysics Data System (ADS)

Jones, Morgan T.; Gislason, Sigurður R.

2008-08-01

Deposition of volcanic ash into aqueous environments leads to dissolution of adsorbed metal salts and aerosols, increasing the bioavailability of key nutrients. Volcanogenic fertilization events could increase marine primary productivity, leading to a drawdown of atmospheric CO 2. Here we conduct flow-through experiments on unhydrated volcanic ash samples from a variety of locations and sources, measuring the concentrations and fluxes of elements into de-ionized water and two contrasting ocean surface waters. Comparisons of element fluxes show that dissolution of adsorbed surface salts and aerosols dominates over glass dissolution, even in sustained low pH conditions. These surface ash-leachates appear unstable, decaying in situ even if kept unhydrated. Volcanic ash from recent eruptions is shown to have a large fertilization potential in both fresh and saline water. Fluorine concentrations are integral to bulk dissolution rates and samples with high F concentrations display elevated fluxes of some nutrients, particularly Fe, Si, and P. Bio-limiting micronutrients are released in large quantities, suggesting that subsequent biological growth will be limited by macronutrient availability. Importantly, acidification of surface waters and high fluxes of toxic elements highlights the potential of volcanic ash-leachates to poison aqueous environments. In particular, large pH changes can cause undersaturation of CaCO 3 polymorphs, damaging populations of calcifying organisms. Deposition of volcanic ash can both fertilize and/or poison aqueous environments, causing significant changes to surface water chemistry and biogeochemical cycles.

Effects of Nutrient Enrichment on Microbial Communities and Carbon Cycling in Wetland Soils

NASA Astrophysics Data System (ADS)

Hartman, W.; Neubauer, S. C.; Richardson, C. J.

2013-12-01

Soil microbial communities are responsible for catalyzing biogeochemical transformations underlying critical wetland functions, including cycling of carbon (C) and nutrients, and emissions of greenhouse gasses (GHG). Alteration of nutrient availability in wetland soils may commonly occur as the result of anthropogenic impacts including runoff from human land uses in uplands, alteration of hydrology, and atmospheric deposition. However, the impacts of altered nutrient availability on microbial communities and carbon cycling in wetland soils are poorly understood. To assess these impacts, soil microbial communities and carbon cycling were determined in replicate experimental nutrient addition plots (control, +N, +P, +NP) across several wetland types, including pocosin peat bogs (NC), freshwater tidal marshes (GA), and tidal salt marshes (SC). Microbial communities were determined by pyrosequencing (Roche 454) extracted soil DNA, targeting both bacteria (16S rDNA) and fungi (LSU) at a depth of ca. 1000 sequences per plot. Wetland carbon cycling was evaluated using static chambers to determine soil GHG fluxes, and plant inclusion chambers were used to determine ecosystem C cycling. Soil bacterial communities responded to nutrient addition treatments in freshwater and tidal marshes, while fungal communities did not respond to treatments in any of our sites. We also compared microbial communities to continuous biogeochemical variables in soil, and found that bacterial community composition was correlated only with the content and availability of soil phosphorus, while fungi responded to phosphorus stoichiometry and soil pH. Surprisingly, we did not find a significant effect of our nutrient addition treatments on most metrics of carbon cycling. However, we did find that several metrics of soil carbon cycling appeared much more related to soil phosphorus than to nitrogen or soil carbon pools. Finally, while overall microbial community composition was weakly correlated with soil carbon cycling, our work did identify a small number of individual taxonomic groups that were more strongly correlated with soil CO2 flux. These results suggest that a small number of microbial groups may potentially serve as keystone taxa (and functional indicators), which simple community fingerprinting approaches may overlook. Our results also demonstrate strong effects of soil phosphorus availability on both microbial communities and soil carbon cycling, even in wetland types traditionally considered to be nitrogen limited.

Xylary pH and Reduction Potential Levels of Iron-stressed Silver Maple (Acer saccharinum L.) 1

PubMed Central

Morris, Robert L.; Swanson, Bert T.

1980-01-01

Xylary fluid pH and reduction potentials were measured on silver maple (Acer saccharinum L.) grown under Fe and pH stress. Although pH and reduction potential (millivolt/59.2) varied significantly in the nutrient solution, xylary pH and reduction potential remained constant. It was concluded that changes in the pH and reduction potential in the xylary fluid of silver maple are not responsible for iron chlorosis. PMID:16661196

Closed nutrient recycling via microbial catabolism in an eco-engineered self regenerating mixed anaerobic microbiome for hydrogenotrophic methanogenesis.

PubMed

Savvas, Savvas; Donnelly, Joanne; Patterson, Tim P; Dinsdale, Richard; Esteves, Sandra R

2017-03-01

A novel eco-engineered mixed anaerobic culture was successfully demonstrated for the first time to be capable of continuous regeneration in nutrient limiting conditions. Microbial catabolism has been found to support a closed system of nutrients able to enrich a culture of lithotrophic methanogens and provide microbial cell recycling. After enrichment, the hydrogenotrophic species was the dominating methanogens while a bacterial substratum was responsible for the redistribution of nutrients. q-PCR results indicated that 7% of the total population was responsible for the direct conversion of the gases. The efficiency of H 2 /CO 2 conversion to CH 4 reached 100% at a gassing rate of above 60v/v/d. The pH of the culture media was effectively sustained at optimal levels (pH 7-8) through a buffering system created by the dissolved CO 2 . The novel approach can reduce the process nutrient/metal requirement and enhance the environmental and financial performance of hydrogenotrophic methanogenesis for renewable energy storage. Copyright © 2016 Elsevier Ltd. All rights reserved.

Histone deacetylase-mediated regulation of endolysosomal pH.

PubMed

Prasad, Hari; Rao, Rajini

2018-05-04

The pH of the endolysosomal system is tightly regulated by a balance of proton pump and leak mechanisms that are critical for storage, recycling, turnover, and signaling functions in the cell. Dysregulation of endolysosomal pH has been linked to aging, amyloidogenesis, synaptic dysfunction, and various neurodegenerative disorders, including Alzheimer's disease. Therefore, understanding the mechanisms that regulate luminal pH may be key to identifying new targets for managing these disorders. Meta-analysis of yeast microarray databases revealed that nutrient-limiting conditions inhibited the histone deacetylase (HDAC) Rpd3 and thereby up-regulated transcription of the endosomal Na + /H + exchanger Nhx1, resulting in vacuolar alkalinization. Consistent with these findings, Rpd3 inhibition by the HDAC inhibitor and antifungal drug trichostatin A induced Nhx1 expression and vacuolar alkalinization. Bioinformatics analysis of Drosophila and mouse databases revealed that caloric control of the Nhx1 orthologs DmNHE3 and NHE6, respectively, is also mediated by HDACs. We show that NHE6 is a target of the transcription factor cAMP-response element-binding protein (CREB), a known regulator of cellular responses to low-nutrient conditions, providing a molecular mechanism for nutrient- and HDAC-dependent regulation of endosomal pH. Of note, pharmacological targeting of the CREB pathway to increase NHE6 expression helped regulate endosomal pH and correct defective clearance of amyloid Aβ in an apoE4 astrocyte model of Alzheimer's disease. These observations from yeast, fly, mouse, and cell culture models point to an evolutionarily conserved mechanism for HDAC-mediated regulation of endosomal NHE expression. Our insights offer new therapeutic strategies for modulation of endolysosomal pH in fungal infection and human disease. © 2018 Prasad and Rao.

Hydrolysis and volatile fatty acids accumulation of waste activated sludge enhanced by the combined use of nitrite and alkaline pH.

PubMed

Huang, Cheng; Liu, Congcong; Sun, Xiuyun; Sun, Yinglu; Li, Rui; Li, Jiansheng; Shen, Jinyou; Han, Weiqing; Liu, Xiaodong; Wang, Lianjun

2015-12-01

Volatile fatty acids (VFAs) production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow hydrolysis and/or poor substrate availability. Increased attention has been given to enhance the hydrolysis and acidification of WAS recently. This study presented an efficient and green strategy based on the combined use of nitrite pretreatment and alkaline pH to stimulate hydrolysis and VFA accumulation from WAS. Results showed that both proteins and polysaccharides increased in the presence of nitrite, indicating the enhancement of sludge solubilization and hydrolysis processes. Mechanism investigations showed that nitrite pretreatment could disintegrate the sludge particle and disperse extracellular polymeric substances (EPS). Then, anaerobic digestion tests demonstrated VFA production increased with nitrite treatment. The maximal VFA accumulation was achieved with 0.1 g N/L nitrite dosage and pH 10.0 at a sludge retention time (SRT) of 7 days, which was much higher VFA production in comparison with the blank, sole nitrite pretreatment, or sole pH 10. The potential analysis suggested that the combined nitrite pretreatment and alkaline pH is capable of enhancing WAS digestion with a great benefit for biological nutrient removal (BNR).

Efficacy of Fe(o,o-EDDHA) and Fe(o,p-EDDHA) isomers in supplying Fe to strategy I plants differs in nutrient solution and calcareous soil.

PubMed

Rojas, Carmen L; Romera, Francisco J; Alcántara, Esteban; Pérez-Vicente, Rafael; Sariego, Cristina; Garcaí-Alonso, J Ignacio; Boned, Javier; Marti, Gabriel

2008-11-26

The FeEDDHA [iron(3+) ethylenediamine di(o-hydroxyphenylacetic) acid] is one of the most efficient iron chelates employed in the correction of iron clorosis in calcareous soils. FeEDDHA presents different positional isomers: the ortho-ortho (o,o), the ortho-para (o,p), and the para-para (p,p). Of these isomers, the p,p cannot chelate Fe in soil solution in a wide range of pH values, while both o,o and o,p can. The objective of this work was to compare the efficiency of both isomers (o,o and o,p) to provide Fe to two Strategy I plants (tomato and peach) in nutrient solution (pH approximately 6.0), as well as in calcareous soil (pH approximately 8.4; CALCIXEREPT). For this, chelates of both o,o-EDDHA and o,p-EDDHA with 57Fe (a nonradioactive isotope of Fe) were used, where the 57Fe acts as a tracer. The results obtained showed that the o,o isomer is capable of providing sufficient Fe to plants in both nutrient solution and calcareous soil. However, the o,p isomer is capable of providing sufficient Fe to plants in nutrient solution but not in calcareous soil.

Microbial enzyme activities of peatland soils in south central Alaska lowlands

EPA Science Inventory

Microbial enzyme activities related to carbon and nutrient acquisition were measured on Alaskan peatland soils as indicators of nutrient limitation and biochemical sustainability. Peat decomposition is mediated by microorganisms and enzymes that in turn are limited by various ph...

Distribution of inorganic species in two Antarctic cryptoendolithic microbial communities

NASA Technical Reports Server (NTRS)

Johnston, C. G.; Vestal, J. R.; Friedmann, E. I. (Principal Investigator)

1989-01-01

Chemical differences were noted between two Antarctic cryptoendolithic (hidden within rock) microenvironments colonized by different microbial communities. Microenvironments dominated by cyanobacteria (BPC) had a higher pH (pH 7-8) than those dominated by lichen (LTL) (pH 4.5-5.5). In order to understand the interactions between the microbiota and the inorganic environment, the inorganic environment was characterized. Water-soluble, carbonate-bound, metal-oxide, organically bound, and residual inorganic species were sequentially extracted from rock samples by chemical means. Each fraction was then quantified using inductively coupled plasma atomic emission spectrometry. BPC contained much more water-soluble and carbonate-bound Ca and Mg than LTL. Metal-oxide species of Al, Fe, and Mn were more abundant in LTL than BPC. Metal oxides appeared to be mobilized (in the order Mn > Fe > Al) from the LTL lichen zone but remained immobile in BPC sandstone. The distribution of K and P bound to metal oxide reflected the distribution of iron oxide in LTL, an indication of the importance of iron in controlling the availability of nutrients in this ecosystem. Metal oxides in turn were likely controlled or influenced by organic matter associated with the lichen community. Despite overall depletion of Fe, Al, and K in the lichen zone, SEM X-ray analysis showed that they were enriched in fungal hyphae. Water-soluble P was present despite the presence of metal oxides, which sequester phosphate. This has biological relevance since P is an essential nutrient.

Site Evaluation Studies of the Massachusetts Bay Disposal Site for Ocean Disposal of Dredged Material

DTIC Science & Technology

1988-07-05

Chemical Characteristics. 101 1. Water Quality. 101 a. Dissolved Oxygen. 101 b. pH. 103 c. Nutrients . 103 d. Turbidity 104 e. Metals. 105 f. Organics...20 - 3 PCB, ppb 10 (0.03) 0.012 0.022 10 102 c. Nutrients Nitrogen and phosphorous compounds are essential nutrients that are metabolized by primary...1973) described nitrate as the limiting nutrient in Massachusetts Bay. Water column analyses of nutri- ents (ammonia, nitrates and phosphorous) were

Effects of Nutrients, Salinity, and pH on Salvinia molesta (Mitchell) Growth

DTIC Science & Technology

2010-07-01

Smart PURPOSE: This study documents effects of macronutrient (nitrogen and phosphorus) concentra- tions, pH, and salinity on giant salvinia growth...investigated. The objective of this study was to document effects of macronutrient (nitrogen and phosphorus) concentrations, pH, and salinity on giant...giant salvinia to become problematic, including low pH, low salinity, and the presence of suitable macronutrients . In combination with distribution

Nutrients levels in paddy soils and flood waters from Tagus-Sado basin: the impact of farming system

NASA Astrophysics Data System (ADS)

Santos, Erika S.; Abreu, Maria Manuela; Magalhães, Maria Clara; Viegas, Wanda; Amâncio, Sara; Cordovil, Cláudia

2017-04-01

Application of fertilizers for crops can contribute to nutrients surplus, namely nitrogen, in both groundwater and surface waters resulting in serious environmental problems. The impacts on water quality due to fertilizers are related to land management. In paddy fields using high amounts of water, the nutrient dynamic knowledge is essential to evaluate the impact of farming system. The aims of this study were to evaluate: i)nutrients levels in soils and floodwaters from rice cultivation in Tagus-Sado basin (Portugal); ii)the effect, under controlled conditions, of different irrigation techniques on nutrient enrichment of floodwaters from rice cultivation. Composite samples (n=24) of paddy soils (0-15 cm) and floodwaters were collected, during rice flooding period. In the field, pH and electrical conductivity (EC) were determined in waters. Soil pH, concentrations of Corganic, NPK and nutrients (Ca, Cu, Fe, Mg, Mn, Zn) in soils and floodwaters (nitrites, nitrates, phosphates) were determined. A mesocosm assay was performed in lysimeters with a paddy soil (pH: 5.6; g/kg- Ntotal: 2.0, Pextractable: 0.04, Kextractable: 0.6, Corganic: 35.5) and different irrigation techniques (n=3): a)flood; b)four floods per day (great water renewal); c)flood until rice flowering and then a normal superficial irrigation. Rice cultivation was done by transplant as in the field. Irrigation water come from a well. Same chemical characterization than in field assay were determined in floodwater and irrigation water. In field conditions, paddy soils had values of pH between 5.1 and 8.1 and a great fertility range (g/kg; Ntotal: 0.4‒2.2; Pextractable: 0.01‒0.2; Kextractable: 0.04‒0.7; Corganic: 6.5‒37.9). Total soil concentrations of Cu, Fe, and Zn in soils were in same range and below maximum admissible values for agriculture. Total soil concentrations of Ca, Mg and Mn, showed higher heterogeneity (g/kg; 1.2‒19.3, 7.6‒34.2 and 0.2‒1.5 respectively). Floodwaters presented pH ≈7 and, usually, EC>1 mS/cm (MRV‒maximum recommended value for irrigation water). Nitrites concentrations were <0.1 mg/L in floodwaters, while concentrations of nitrates (<2.4 mg/L), Cu (<2‒12.3 µg/L), Fe (<0.1‒0.9 mg/L) and Zn (0.04‒1.9 mg/L) were below MRV. The fertilizers used in rice cultivation did not seem to affect the water quality. Nitrates concentration in irrigation water of lysimeters (24 mg/L) was close to MVR for irrigation water. Intensive agriculture of corn surrounding the well can explain the greater nutrients concentrations, especially nitrates, nitrites and phosphates, in this water compared to water from river used for paddy fields irrigation. Independently of irrigation technique, nutrient concentrations in lysimeters floodwaters (except phosphates in some samples) were in same range of those in irrigation water from well. The nutrients excess in water seems not to be uptake by rice contributing to nutrient enrichment of nearby waters and soils. Studied paddy fields from Tejo-Sado basin are not a potential pollution source of nutrients. However, according mesocosm assay, the potential irrigation of paddy soils with water rich in nitrates can contribute to serious environmental risks. The authors are thankful to: Atlantic Meals for financial and sampling support, and NitroPortugal, H2020-TWINN-2015, EU coordination and support action n. 692331 funding.

[Soil fertility characteristics under different land use patterns in depressions between karst hills].

PubMed

Liu, Yan; Song, Tong-Qing; Cai, De-Suo; Zeng, Fu-Ping; Peng, Wan-Xia; Du, Hu

2014-06-01

Soil samples were collected from the depressions between karst hills by grid sampling method (5 m x 5 m), soil pH, soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) in surface layer (0-20 cm) under different land use patterns (burning, cutting, cutting plus root removal, enclosure, maize plantation, and pasture plantation) were measured, the main factors of influencing the soil fertility was identified by principal component analysis (PCA), and the relationships between soil nutrients and microorganisms were demonstrated by canonical correlation analysis (CCA). The results showed that the soil was slightly alkaline (pH 7.83-7.98), and the soil fertility differed under the different land use patterns, with 76.78-116.05 g x kg(-1) of SOC, 4.29-6.23 g x kg(-1) of TN, 1.15-1.47 g x kg(-1) of TP, 3.59-6.05 g x kg(-1) of TK, 331.49-505.49 mg x kg(-1) of AN), 3.92-10.91 mg x kg(-1) of AP, and 136.28-198.10 mg x kg(-1) of AK. These soil indexes except pH showed moderate or strong variation. Different land use patterns had various impacts on soil fertility: Soil nutrients such as SOC, TN, TP, and AN were most significantly influenced by land use patterns in the depressions between karst hills; Followed by soil microorganisms, especially soil actinomycetes, and the effect decreased with the increasing gradient of human disturbance from enclosure, burning, cutting, cutting plus root removal, pasture plantation, and maize plantation. CCA elucidated that considerable interactions existed in soil TP with MBP (microbial biomass phosphorus), TK with MBC (microbial biomass carbon), TN with actinomycetes in the burned area, while TN and MBC in the cutting treatment, AP and MBN (microbial biomass nitrogen) in the treatment of cutting plus root removal, pH with MBC and fungus in the enclosure treatment, TN and TK with MBP in the maize plantation, pH with fungi and actinomycetes in the pasture plantation. Land use patterns changed the soil fertility in the depressions between karst hills; therefore, in the ecological restoration and reconstruction of karst region with fragmented landforms and shallow soil, rational land use patterns should be adopted to improve the soil quality of degraded ecosystems.

Opportunities and challenges in the use of coal fly ash for soil improvements--a review.

PubMed

Shaheen, Sabry M; Hooda, Peter S; Tsadilas, Christos D

2014-12-01

Coal fly ash (CFA), a by-product of coal combustion has been regarded as a problematic solid waste, mainly due to its potentially toxic trace elements, PTEs (e.g. Cd, Cr, Ni, Pb) and organic compounds (e.g. PCBs, PAHs) content. However, CFA is a useful source of essential plant nutrients (e.g. Ca, Mg, K, P, S, B, Fe, Cu and Zn). Uncontrolled land disposal of CFA is likely to cause undesirable changes in soil conditions, including contamination with PTEs, PAHs and PCBs. Prudent CFA land application offers considerable opportunities, particularly for nutrient supplementation, pH correction and ameliorating soil physical conditions (soil compaction, water retention and drainage). Since CFA contains little or no N and organic carbon, and CFA-borne P is not readily plant available, a mixture of CFA and manure or sewage sludge (SS) is better suited than CFA alone. Additionally, land application of such a mixture can mitigate the mobility of SS-borne PTEs, which is known to increase following cessation of SS application. Research analysis further shows that application of alkaline CFA with or without other amendments can help remediate at least marginally metal contaminated soils by immobilisation of mobile metal forms. CFA land application with SS or other source of organic carbon, N and P can help effectively reclaim/restore mining-affected lands. Given the variability in the nature and composition of CFA (pH, macro- and micro-nutrients) and that of soil (pH, texture and fertility), the choice of CFA (acidic or alkaline and its application rate) needs to consider the properties and problems of the soil. CFA can also be used as a low cost sorbent for the removal of organic and inorganic contaminants from wastewater streams; the disposal of spent CFA however can pose further challenges. Problems in CFA use as a soil amendment occur when it results in undesirable change in soil pH, imbalance in nutrient supply, boron toxicity in plants, excess supply of sulphate and PTEs. These problems, however, are usually associated with excess or inappropriate CFA applications. The levels of PAHs and PCBs in CFA are generally low; their effects on soil biota, uptake by plants and soil persistence, however, need to be assessed. In spite of this, co-application of CFA with manure or SS to land enhances its effectiveness in soil improvements. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nanoparticle-based measurements of pH and O2 dynamics in the rhizosphere of Zostera marina L.: effects of temperature elevation and light-dark transitions.

PubMed

Elgetti Brodersen, Kasper; Koren, Klaus; Lichtenberg, Mads; Kühl, Michael

2016-07-01

Seagrasses can modulate the geochemical conditions in their immediate rhizosphere through the release of chemical compounds from their below-ground tissue. This is a vital chemical defence mechanism, whereby the plants detoxify the surrounding sediment. Using novel nanoparticle-based optical O2 and pH sensors incorporated in reduced and transparent artificial sediment, we investigated the spatio-temporal dynamics of pH and O2 within the entire rhizosphere of Zostera marina L. during experimental manipulations of light and temperature. We combined such measurements with O2 microsensor measurements of the photosynthetic productivity and respiration of seagrass leaves. We found pronounced pH and O2 microheterogeneity within the immediate rhizosphere of Z. marina, with higher below-ground tissue oxidation capability and rhizoplane pH levels during both light exposure of the leaf canopy and elevated temperature, where the temperature-mediated stimuli of biogeochemical processes seemed to predominate. Low rhizosphere pH microenvironments appeared to correlate with plant-derived oxic microzones stimulating local sulphide oxidation and thus driving local proton generation, although the rhizoplane pH levels generally where much higher than the bulk sediment pH. Our data show that Z. marina can actively alter its rhizosphere pH microenvironment alleviating the local H2 S toxicity and enhancing nutrient availability in the adjacent sediment via geochemical speciation shift. © 2016 John Wiley & Sons Ltd.

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

NASA Astrophysics Data System (ADS)

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

2017-04-01

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

The effects of human milk fortification on nutrients and milk properties.

PubMed

Donovan, R; Kelly, S G; Prazad, P; Talaty, P N; Lefaiver, C; Hastings, M L; Everly, D N

2017-01-01

To investigate the effects of fortification and storage on nutrients and properties of various human milk (HM) types. Mother's own milk (MOM) and pasteurized donor human milk (DHM; n=118) were analyzed pre- and post fortification with Enfamil and Similac human milk fortifier (EHMF and SHMF) before and after 24 h of refrigerated storage. Milk fortified with SHMF had significantly greater osmolality, pH and lipase activity than EHMF. Changes in protein, pH and osmolality following refrigerated storage differed between fortifiers. When milk type was factored into the analysis, protein and lipase activity changes in fresh MOM differed significantly from DHM and frozen MOM. Analysis of UNF HM found higher protein levels in preterm vs term samples and in MOM vs DHM. Nutrient composition of HM varies significantly by milk type. Although fortifiers enhance select nutrients, each has the potential to affect HM properties in a unique way and these affects may vary by milk type.

Organic wastes from bioenergy and ecological sanitation as soil fertility improver: a field experiment in a tropical Andosol

NASA Astrophysics Data System (ADS)

Krause, A.; Nehls, T.; George, E.; Kaupenjohann, M.

2015-11-01

Andosols require the regular application of phosphorus (P) to sustain crop productivity. In a practice oriented field experiment at an Andosol site in NW Tanzania, the effects of various soil amendments (standard compost, urine, biogas slurry and CaSa-compost [biochar and sanitized human excreta]) on (i) the productivity of locally grown crop species, on (ii) the plants' nutrient status and on (iii) the soil's physico-chemical properties were studied. None of the amendments had any significant effect on soil moisture, so the observed variation in crop yield and plant nutrition reflected differences in nutrient availability. The application of CaSa-compost increased the level of available P in the top-soil from 0.5 to 4.4 mg kg-1 and the soil pH from 5.3 to 5.9. Treatment with biogas slurry, standard compost and CaSa-compost increased the above-ground biomass of Zea mays by, respectively, 140, 154 and 211 %. The grain yields of maize on soil treated with biogas slurry, standard compost and CaSa-compost were, respectively, 2.63, 3.18 and 4.40 t ha-1, compared to only 1.10 t ha-1 on unamended plots. All treatments enhanced crop productivity and increased the uptake of nutrients into the maize grains. The CaSa-compost was especially effective in mitigating P deficiency and soil acidification. We conclude that all treatments are viable as substitute for synthetic fertilizers. However, further steps are required to integrate the tested soil amendments into farm-scale nutrient management and to balance the additions and removals of nutrients, so that the loop can be closed.

Potato growth and yield using nutrient film technique (NFT)

NASA Technical Reports Server (NTRS)

Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.; Knott, W. M.; Hinkle, C. R.

1990-01-01

Potato plants, cvs Denali and Norland, were grown in polyvinyl chloride (PVC) trays using a continuous flowing nutrient film technique (NFT) to study tuber yield for NASA's Controlled Ecological Life Support Systems (CELSS) program. Nutrient solution pH was controlled automatically using 0.39M (2.5% (v/v) nitric acid (HNO3), while water and nutrients were replenished manually each day and twice each week, respectively. Plants were spaced either one or two per tray, allotting 0.2 or 0.4 m2 per plant. All plants were harvested after 112 days. Denali plants yielded 2850 and 2800 g tuber fresh weight from the one- and two-plant trays, respectively, while Norland plants yielded 1800 and 2400 g tuber fresh weight from the one- and two-plant trays. Many tubers of both cultivars showed injury to the periderm tissue, possibly caused by salt accumulation from the nutrient solution on the surface. Total system water usage throughout the study for all the plants equaled 709 liters (L), or approximately 2 L m-2 d-1. Total system acid usage throughout the study (for nutrient solution pH control) equaled 6.60 L, or 18.4 ml m-2 d-1 (7.2 mmol m-2 d-1). The results demonstrate that continuous flowing nutrient film technique can be used for tuber production with acceptable yields for the CELSS program.

The yeast protein kinase Sch9 adjusts V-ATPase assembly/disassembly to control pH homeostasis and longevity in response to glucose availability.

PubMed

Wilms, Tobias; Swinnen, Erwin; Eskes, Elja; Dolz-Edo, Laura; Uwineza, Alice; Van Essche, Ruben; Rosseels, Joëlle; Zabrocki, Piotr; Cameroni, Elisabetta; Franssens, Vanessa; De Virgilio, Claudio; Smits, Gertien J; Winderickx, Joris

2017-06-01

The conserved protein kinase Sch9 is a central player in the nutrient-induced signaling network in yeast, although only few of its direct substrates are known. We now provide evidence that Sch9 controls the vacuolar proton pump (V-ATPase) to maintain cellular pH homeostasis and ageing. A synthetic sick phenotype arises when deletion of SCH9 is combined with a dysfunctional V-ATPase, and the lack of Sch9 has a significant impact on cytosolic pH (pHc) homeostasis. Sch9 physically interacts with, and influences glucose-dependent assembly/disassembly of the V-ATPase, thereby integrating input from TORC1. Moreover, we show that the role of Sch9 in regulating ageing is tightly connected with V-ATPase activity and vacuolar acidity. As both Sch9 and the V-ATPase are highly conserved in higher eukaryotes, it will be interesting to further clarify their cooperative action on the cellular processes that influence growth and ageing.

Hydroponic system design with real time OS based on ARM Cortex-M microcontroller

NASA Astrophysics Data System (ADS)

Atmadja, Wiedjaja; Liawatimena, Suryadiputra; Lukas, Jonathan; Nata, Eka Putra Leo; Alexander, Ivan

2017-12-01

Hydroponic is the process of growing plants without soil, plant root flooded or moist with nutrient-rich solutions in inert material. Hydroponics has become a reality for greenhouse growers in virtually all climates. Large hydroponic installations exist throughout the world for growing flowers, vegetables and some short period fruit like tomato and cucumber. In soilless culture, we must maintain stable pH and conductivity level of nutrient solution to make plant grow well, large variation of pH of certain time will poisoned plant. This paper describes development complete automation hydroponic system, from maintaining stable nutrient composition (conductivity and pH), grow light, and monitor plant environment such as CO2, temperature and humidity. The heart of our automation is ARM Cortex-M4 from ST Microelectronic running ARM mbed OS, the official Real Time Operating System (RTOS) for ARM Cortex-M microcontroller. Using RTOS gives us flexibility to have multithreaded process. Results show that system capable to control desired concentration level with variation of less than 3%, pH sensor show good accuracy 5.83% from pH value 3.23-10. Growing light intensity measurement show result 105 μmol/m2/s therefore we need turn on the light at least 17 hours/day to fulfil plant light requirement. RTOS give good performance with latency and jitter less than 15 us, system overall show good performance and accuracy for automating hydroponic plant in vegetative phase of growth.

Recapturing nutrients from dairy waste using biochar

NASA Astrophysics Data System (ADS)

Sarkhot, D.; Ghezzehei, T. A.; Berhe, A. A.

2009-12-01

Biochar or biomass derived black carbon is known to be highly resistant to decomposition with half-life periods ranging from hundreds of years to millennia. It is also reported to enhance soil productivity due to high nutrient retention and favorable effects on soil pH, water retention capacity as well as microbial population. Brazilian Terra Preta soils have shown the potential of biochar for long-term carbon sequestration capacity and productivity of soil and many researchers have now focused on utilizing this phenomenon to create fertile, carbon-rich soils, called Terra Preta Nova. Although the highly adsorptive nature of biochar is well characterized, the potential for using biochar in environmental cleanup efforts is relatively unexplored. Dairy waste is a source of significant water pollution because it introduces excess nutrients such as phosphates and nitrates into the soil and water system. Since many soils have limited capacity to retain nitrate and phosphate, especially for long periods of time, the utility of dairy waste manure to enhance soil fertility and nutrient availability to plants is limited. Here, we present results from a project that we started to determine the potential of biochar to recover the excess nutrients from dairy flushed manure. In this initial study, a commercially available biochar amendment was ground and used in a batch sorption experiment with the dairy flushed manure from a local dairy in Merced, California. Four manure dilutions viz. 10, 25, 50 and 100%, and three shaking times, viz. 1, 12 and 24 hours were used for this study. We then calculated the amount of ammonia, nitrate and phosphate adsorbed by the biochar using differences in nutrient concentrations before and after the sorption experiment. Biochar showed significant capacity of adsorbing these nutrients, suggesting a potential for controlling the dairy pollution. The resulting enriched biochar can potentially act as a slow release fertilizer and enhance soil productivity as well as increasing the long-term carbon sequestration potential of soils. We are currently initiating further research to determine the desorption potenial of the biochar sorbed nutrients in soil.

Effects of irradiation intensity and pH on nutrients release and solids destruction of waste activated sludge using the microwave-enhanced advanced oxidation process.

PubMed

Chan, W I; Liao, P H; Lo, K V

2010-11-01

Using the microwave-enhanced advanced oxidation process (MW/H2O2-AOP), the pH and irradiation intensity on waste activated sludge samples were investigated to provide insight to the athermal effects on nutrients release, solids destruction, particle size distribution and dewaterability, and to demonstrate their interrelationships. Carbonaceous matters and nutrients released into solution depended on the irradiation intensity and time. Higher irradiation levels tended to be more effective in the solubilization of nutrients and had more pronounced effects in the dewaterability of sludge. In terms of particle size distribution, detectable particles increased in size for treatments in acidic conditions, while the dewaterability of treated sludge was improved. In treatments under neutral and alkaline conditions, the particle size range increased, with more small particles formed, thereby significantly deteriorating the dewaterability of sludge treated in alkaline conditions. The best results for the solubilization of nutrients were in alkaline conditions with high irradiation power, but dewaterability of the sludge was compromised. Sludge treatment with the MW/H2O2-AOP in acidic conditions with high irradiation power yielded the best dewaterable sludge and significant nutrient solubilization; therefore, it is the recommended treatment condition for activated sludge.

Effects of chemical elements in the trophic levels of natural salt marshes.

PubMed

Kamiński, Piotr; Barczak, Tadeusz; Bennewicz, Janina; Jerzak, Leszek; Bogdzińska, Maria; Aleksandrowicz, Oleg; Koim-Puchowska, Beata; Szady-Grad, Małgorzata; Klawe, Jacek J; Woźniak, Alina

2016-06-01

The relationships between the bioaccumulation of Na, K, Ca, Mg, Fe, Zn, Cu, Mn, Co, Cd, and Pb, acidity (pH), salinity (Ec), and organic matter content within trophic levels (water-soil-plants-invertebrates) were studied in saline environments in Poland. Environments included sodium manufactures, wastes utilization areas, dumping grounds, and agriculture cultivation, where disturbed Ca, Mg, and Fe exist and the impact of Cd and Pb is high. We found Zn, Cu, Mn, Co, and Cd accumulation in the leaves of plants and in invertebrates. Our aim was to determine the selectivity exhibited by soil for nutrients and heavy metals and to estimate whether it is important in elucidating how these metals are available for plant/animal uptake in addition to their mobility and stability within soils. We examined four ecological plant groups: trees, shrubs, minor green plants, and water macrophytes. Among invertebrates, we sampled breastplates Malacostraca, small arachnids Arachnida, diplopods Diplopoda, small insects Insecta, and snails Gastropoda. A higher level of chemical elements was found in saline polluted areas (sodium manufactures and anthropogenic sites). Soil acidity and salinity determined the bioaccumulation of free radicals in the trophic levels measured. A pH decrease caused Zn and Cd to increase in sodium manufactures and an increase in Ca, Zn, Cu, Cd, and Pb in the anthropogenic sites. pH increase also caused Na, Mg, and Fe to increase in sodium manufactures and an increase in Na, Fe, Mn, and Co in the anthropogenic sites. There was a significant correlation between these chemical elements and Ec in soils. We found significant relationships between pH and Ec, which were positive in saline areas of sodium manufactures and negative in the anthropogenic and control sites. These dependencies testify that the measurement of the selectivity of cations and their fluctuation in soils provide essential information on the affinity and binding strength in these environments. The chemical elements accumulated in soils and plants; however, further flow is selective and variable. The selectivity exhibited by soil systems for nutrients and heavy metals is important in elucidating how these metals become available for plant/animal uptake and also their mobility and stability in soils.

Biochar application to hardrock mine tailings: Soil quality, microbial activity, and toxic element sorption

USGS Publications Warehouse

Kelly, Charlene N.; Peltz, Christopher D.; Stanton, Mark R.; Rutherford, David W.; Rostad, Colleen E.

2014-01-01

Waste rock piles from historic mining activities remain unvegetated as a result of metal toxicity and high acidity. Biochar has been proposed as a low-cost remediation strategy to increase soil pH and reduce leaching of toxic elements, and improve plant establishment. In this laboratory column study, biochar made from beetle-killed pine wood was assessed for utility as a soil amendment by mixing soil material from two mine sites collected near Silverton, Colorado, USA with four application rates of biochar (0%, 10%, 20%, 30% vol:vol). Columns were leached seven times over 65 days and leachate pH and concentration of toxic elements and base cations were measured at each leaching. Nutrient availability and soil physical and biological parameters were determined following the incubation period. We investigated the hypotheses that biochar incorporation into acidic mine materials will (1) reduce toxic element concentrations in leaching solution, (2) improve soil parameters (i.e. increase nutrient and water holding capacity and pH, and decrease compaction), and (3) increase microbial populations and activity. Biochar directly increased soil pH (from 3.33 to 3.63 and from 4.07 to 4.77 in the two materials) and organic matter content, and decreased bulk density and extractable salt content in both mine materials, and increased nitrate availability in one material. No changes in microbial population or activity were detected in either mine material upon biochar application. In leachate solution, biochar increased base cations from both materials and reduced the concentrations of Al, Cd, Cu, Pb, and Zn in leachate solution from one material. However, in the material with greater toxic element content, biochar did not reduce concentrations of any measured dissolved toxic elements in leachate and resulted in a potentially detrimental release of Cd and Zn into solution at concentrations above that of the pure mine material. The length of time of effectiveness and specific sorption by biochar is variable by element and the toxic element concentration and acidity of the initial mine material.

Evaluation of Eurasian Watermilfoil Control Techniques Using Aquatic Herbicides in Fort Peck Lake, Montana

DTIC Science & Technology

2015-07-01

19 Table 3. Temperature , dissolved oxygen , pH, and wind...21 Table 4. Temperature , dissolved oxygen , and pH measured in the study plots following treatment, Fort Peck Lake, MT, 2012...quality, particularly temperature , pH, dissolved oxygen , and nutrient cycling (Prentki et al. 1979; Carpenter and Lodge 1986, Frodge et al. 1990; Boylen

Microwave enhanced oxidation treatment of organic fertilizers.

PubMed

More, Abhilasha; Srinivasan, Asha; Liao, Ping Huang; Lo, Kwang Victor

2017-08-01

Liquid organic fertilizers (LOFs) are relatively easier to degrade than those of solid organic fertilizers, and the nutrients are readily available for plant uptake. Microwave enhanced advanced oxidation treatment (MW/H 2 O 2 -AOP) was used to convert solid organic fertilizers (insoluble blood meal, bone meal, feather meal, sunflower ash and a mixture) into LOF. After the MW/H 2 O 2 -AOP treatment, high soluble nitrogen (11-29%), soluble phosphorus (64%) and potassium (92%), as well as low total suspended solids content could be obtained. The resulting LOF would make the nutrients more bioavailable, and would provide some of them for the plant uptake immediately. Temperature and hydrogen peroxide dosage were found to be significant factors affecting nitrogen release from blood meal and feather meal, while temperature and pH were found to be significant factors for solubilizing phosphorus and potassium from bone meal and ash, respectively. The MW/H 2 O 2 -AOP reduced suspended solids, and released nutrients into solution; therefore, it was an effective treatment method to make LOFs. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Meet EPA Ecologist Michael Murrell, Ph.D.

EPA Pesticide Factsheets

Michael Murrel, Ph.D., is a EPA research ecologist working on the Gulf of Mexico Hypoxia Project, helping develop models of the northern Gulf to quantify the links between freshwater flowing into the Gulf from the land, nutrients, and hypoxia—“dead zones”

Mitochondrial matrix pH controls oxidative phosphorylation and metabolism-secretion coupling in INS-1E clonal beta cells.

PubMed

Akhmedov, Dmitry; Braun, Matthias; Mataki, Chikage; Park, Kyu-Sang; Pozzan, Tullio; Schoonjans, Kristina; Rorsman, Patrik; Wollheim, Claes B; Wiederkehr, Andreas

2010-11-01

Glucose-evoked mitochondrial signals augment ATP synthesis in the pancreatic β cell. This activation of energy metabolism increases the cytosolic ATP/ADP ratio, which stimulates plasma membrane electrical activity and insulin granule exocytosis. We have recently demonstrated that matrix pH increases during nutrient stimulation of the pancreatic β cell. Here, we have tested whether mitochondrial matrix pH controls oxidative phosphorylation and metabolism-secretion coupling in the rat β-cell line INS-1E. Acidification of the mitochondrial matrix pH by nigericin blunted nutrient-dependent respiratory and ATP responses (continuously monitored in intact cells). Using electrophysiology and single cell imaging, we find that the associated defects in energy metabolism suppress glucose-stimulated plasma membrane electrical activity and cytosolic calcium transients. The same parameters were unaffected after direct stimulation of electrical activity with tolbutamide, which bypasses mitochondrial function. Furthermore, lowered matrix pH strongly inhibited sustained, but not first-phase, insulin secretion. Our results demonstrate that the matrix pH exerts a control function on oxidative phosphorylation in intact cells and that this mode of regulation is of physiological relevance for the generation of downstream signals leading to insulin granule exocytosis. We propose that matrix pH serves a novel signaling role in sustained cell activation.

Phytoplankton and nutrient dynamics in Winyah Bay, SC.

NASA Astrophysics Data System (ADS)

Boneillo, G. E.; Brooks, S. S.; Brown, S. L.; Woodford, K. M.; Wright, C. R.

2016-02-01

Winyah Bay is a coastal plain estuary located in South Carolina that has been classified for a moderate risk of Eutrophication by NOAA. Winyah Bay receives freshwater input from four rivers, the Waccamaw, Sampit, Black, and Pee Dee Rivers. The Waccamaw, Sampit and Black River are blackwater systems that discharge elevated amounts of colored dissolved organic matter. During the summer and fall of 2015, bioassay experiments were performed to simultaneously examine both light and nutrient (nitrogen & phosphate) limitation throughout Winyah Bay. Sampling stations near the mouth of the Waccamaw and Sampit Rivers showed that phytoplankton were light limited in the late summer instead of nutrient limited. These stations were located in the industrialized area of the bay and typically had the highest nutrient concentrations and highest turbidity, with Secchi depths typically less than 0.5 meters. Results indicated that phytoplankton may be nitrogen limited near the mouth of Winyah Bay, where nutrient concentrations and turbidity were observed to be lower than locations further upstream. There was also an observed dissolved oxygen and pH gradient during the summer of 2015. Dissolved oxygen levels less than 4.0 mg/L were routinely observed near the industrialized head of the estuary and corresponded with lower pH values.

Water quality of Tampa Bay, Florida, June 1972-May 1976

USGS Publications Warehouse

Goetz, Carole L.; Goodwin, Carl R.

1980-01-01

A comprehensive assessment of the water quality of Tampa Bay, Florida, was initiated in 1970 to provide background information to evaluate the effects of widening and deepening the ship channel to the port of Tampa. This report provides results of water-quality sampling in the bay from 1972 to 1976, prior to dredging. Measurements of temperature, dissolved oxygen, pH, turbidity, specific conductance, biochemical oxygen demand, and total organic carbon were made as well as measurements for several nutrient, metal, and pesticide parameters. Many parameters were measured at as many as three points in the vertical. These data indicate that Tampa Bay is well-mixed vertically with little density stratification. Time histories of average temperature, dissolved oxygen, pH, turbidity, specific conductance and nutrient values within four subareas of Tampa Bay are given to reveal seasonal or other trends during the period of record. Temperature, dissolved oxygen, pH, turbidity, specific conductance, nutrient, biochemical oxygen demand, total organic carbon, and metal data are also presented as areal distributions. Nutrient concentrations were generally higher in Hillsborough Bay than in other sub-areas of Tampa Bay. Biochemical oxygen demand, total organic carbon, and total organic nitrogen distribution patterns show regions of highest concentrations to be along bay shorelines near population centers. Of the metals analyzed, all were present in concentrations of less than 1 milligram per liter. (USGS)

Monitoring the Productivity of Coastal Systems Using PH: When Simpler is Better

EPA Science Inventory

The impact of nutrient inputs to the eutrophication of coastal ecosystems has been one of the great themes of coastal ecology. There have been countless studies devoted to quantifying how human sources of nutrients, in particular nitrogen (N), effect coastal water bodies. These s...

Monitoring the Productivity of Coastal Systems Using PH: When Simpler is Better (NEERS)

EPA Science Inventory

The impact of nutrient inputs to the eutrophication of coastal ecosystems has been one of the great themes of coastal ecology. There have been countless studies devoted to quantifying how human sources of nutrients, in particular nitrogen (N), effect coastal water bodies. These s...

Monitoring the Productivity of Coastal Systems Using PH: When Simpler is Better.

EPA Science Inventory

The impact of nutrient inputs to the eutrophication of coastal ecosystems has been one of the great themes of coastal ecology. There have been countless studies devoted to quantifying how human sources of nutrients, in particular nitrogen (N), effect coastal water bodies. These s...

Soil properties affecting wheat yields following drilling-fluid application.

PubMed

Bauder, T A; Barbarick, K A; Ippolito, J A; Shanahan, J F; Ayers, P D

2005-01-01

Oil and gas drilling operations use drilling fluids (mud) to lubricate the drill bit and stem, transport formation cuttings to the surface, and seal off porous geologic formations. Following completion of the well, waste drilling fluid is often applied to cropland. We studied potential changes in soil compaction as indicated by cone penetration resistance, pH, electrical conductivity (EC(e)), sodium adsorption ratio (SAR), extractable soil and total straw and grain trace metal and nutrient concentrations, and winter wheat (Triticum aestivum L. 'TAM 107') grain yield following water-based, bentonitic drilling-fluid application (0-94 Mg ha(-1)) to field test plots. Three methods of application (normal, splash-plate, and spreader-bar) were used to study compaction effects. We measured increasing SAR, EC(e), and pH with drilling-fluid rates, but not to levels detrimental to crop production. Field measurements revealed significantly higher compaction within areas affected by truck travel, but also not enough to affect crop yield. In three of four site years, neither drilling-fluid rate nor application method affected grain yield. Extractions representing plant availability and plant analyses results indicated that drilling fluid did not significantly increase most trace elements or nutrient concentrations. These results support land application of water-based bentonitic drilling fluids as an acceptable practice on well-drained soils using controlled rates.

Permeation of membranes by the neutral form of amino acids and peptides: relevance to the origin of peptide translocation

NASA Technical Reports Server (NTRS)

Chakrabarti, A. C.; Deamer, D. W.; Miller, S. L. (Principal Investigator)

1994-01-01

The flux of amino acids and other nutrient solutes such as phosphate across lipid bilayers (liposomes) is 10(5) slower than facilitated inward transport across biological membranes. This suggest that primitive cells lacking highly evolved transport systems would have difficulty transporting sufficient nutrients for cell growth to occur. There are two possible ways by which early life may have overcome this difficulty: (1) The membranes of the earliest cellular life-forms may have been intrinsically more permeable to solutes; or (2) some transport mechanism may have been available to facilitate transbilayer movement of solutes essential for cell survival and growth prior to the evolution of membrane transport proteins. Translocation of neutral species represents one such mechanism. The neutral forms of amino acids modified by methylation (creating protonated weak bases) permeate membranes up to 10(10) times faster than charged forms. This increased permeability when coupled to a transmembrane pH gradient can result in significantly increased rates of net unidirectional transport. Such pH gradients can be generated in vesicles used to model protocells that preceded and were presumably ancestral to early forms of life. This transport mechanism may still play a role in some protein translocation processes (e.g. for certain signal sequences, toxins and thylakoid proteins) in vivo.

Nutrients content and quality of liquid fertilizer made from goat manure

NASA Astrophysics Data System (ADS)

Sunaryo, Yacobus; Purnomo, Djoko; Theresia Darini, Maria; Ratri Cahyani, Vita

2018-05-01

Quality of liquid fertilizer is determined by the content of nutrients and other chemical factors such as pH and EC. This research aimed to examine nutrient contents and dynamic of pH and EC of liquid fertilizer made from goat manure in combination with sugar and ammonium sulfate (ZA) and using Effective Microorganisms (EM) as the decomposer. This research was conducted by employing 3 x 3 factorial experiment with three replications. Each treatment combination was applied in 20 L of water. The first factor was the quantity of sugar which consisted of 3 levels: 12.5, 25, and 50 g L-1 of water. The second factor was the quantity of ZA which consisted of 3 levels: 25, 37.5, and 50 g L-1 of water. All combinations were added by 100 g of air dried goat manure L-1 of water and EM solution 1 ml L-1 of water, and incubated for five months. Results of the experiment indicated that the increasing concentration of ZA resulted in the significantly increase of N total and S total. Increasing concentration of sugar resulted in decreasing pH and increasing lactic acid; whereas, increasing concentration of ZA followed by increasing Electrical Conductivity (EC). There was no significantly change of pH and EC of the liquid fertilizer during five months incubation.

Penguins significantly increased phosphine formation and phosphorus contribution in maritime Antarctic soils.

PubMed

Zhu, Renbin; Wang, Qing; Ding, Wei; Wang, Can; Hou, Lijun; Ma, Dawei

2014-11-14

Most studies on phosphorus cycle in the natural environment focused on phosphates, with limited data available for the reduced phosphine (PH3). In this paper, matrix-bound phosphine (MBP), gaseous phosphine fluxes and phosphorus fractions in the soils were investigated from a penguin colony, a seal colony and the adjacent animal-lacking tundra and background sites. The MBP levels (mean 200.3 ng kg(-1)) in penguin colony soils were much higher than those in seal colony soils, animal-lacking tundra soils and the background soils. Field PH3 flux observation and laboratory incubation experiments confirmed that penguin colony soils produced much higher PH3 emissions than seal colony soils and animal-lacking tundra soils. Overall high MBP levels and PH3 emissions were modulated by soil biogeochemical processes associated with penguin activities: sufficient supply of the nutrients phosphorus, nitrogen, and organic carbon from penguin guano, high soil bacterial abundance and phosphatase activity. It was proposed that organic or inorganic phosphorus compounds from penguin guano or seal excreta could be reduced to PH3 in the Antarctic soils through the bacterial activity. Our results indicated that penguin activity significantly increased soil phosphine formation and phosphorus contribution, thus played an important role in phosphorus cycle in terrestrial ecosystems of maritime Antarctica.

Penguins significantly increased phosphine formation and phosphorus contribution in maritime Antarctic soils

PubMed Central

Zhu, Renbin; Wang, Qing; Ding, Wei; Wang, Can; Hou, Lijun; Ma, Dawei

2014-01-01

Most studies on phosphorus cycle in the natural environment focused on phosphates, with limited data available for the reduced phosphine (PH3). In this paper, matrix-bound phosphine (MBP), gaseous phosphine fluxes and phosphorus fractions in the soils were investigated from a penguin colony, a seal colony and the adjacent animal-lacking tundra and background sites. The MBP levels (mean 200.3 ng kg−1) in penguin colony soils were much higher than those in seal colony soils, animal-lacking tundra soils and the background soils. Field PH3 flux observation and laboratory incubation experiments confirmed that penguin colony soils produced much higher PH3 emissions than seal colony soils and animal-lacking tundra soils. Overall high MBP levels and PH3 emissions were modulated by soil biogeochemical processes associated with penguin activities: sufficient supply of the nutrients phosphorus, nitrogen, and organic carbon from penguin guano, high soil bacterial abundance and phosphatase activity. It was proposed that organic or inorganic phosphorus compounds from penguin guano or seal excreta could be reduced to PH3 in the Antarctic soils through the bacterial activity. Our results indicated that penguin activity significantly increased soil phosphine formation and phosphorus contribution, thus played an important role in phosphorus cycle in terrestrial ecosystems of maritime Antarctica. PMID:25394572

Removal of excess nutrients by Australian zeolite during anaerobic digestion of swine manure.

PubMed

Wijesinghe, D Thushari N; Dassanayake, Kithsiri B; Scales, Peter; Sommer, Sven G; Chen, Deli

2018-03-21

The objective of this study was to investigate the feasibility of using natural and NaCl-treated Australian zeolites to simultaneously remove excess nutrients from anaerobically digested swine manure. Ion adsorption and desorption properties of Australian zeolite during the anaerobic digestion of swine manure were investigated. Two experiments were conducted: the first was an adsorption experiment with multi-component solutions that corresponded with the ionic composition of swine manure digestates. The second experiment determined the effects of zeolite dose rates during anaerobic digestion of swine manure on the removal of N, P and K from solution. Adsorption isotherms confirmed selectivity for K + over NH 4 + by Australian natural and sodium zeolites. Therefore, NH 4 + removal was considerably reduced when there was simultaneous K + uptake. Natural zeolite desorbed more Ca 2+ during K + and NH 4 + adsorption than sodium zeolite. The ion exchange reaction was independent of the presence of P. P removal was very dependent on the pH of the medium. Natural Australian zeolite was shown to be a potential sorbent for the removal of NH 4 + , K + and P during the anaerobic digestion of swine manure. However, the application of high concentrations of zeolite at higher pH values (> 7.5) might not be appropriate for anaerobic digestion, because zeolite desorbed more Ca 2+ ions into the solution at the higher doses of zeolite and then availability of P for microbial growth might be reduced as a result of PO 4 3- precipitation with Ca 2+ at the higher pH.

Vulnerability of Coral Reefs to Bioerosion From Land-Based Sources of Pollution

NASA Astrophysics Data System (ADS)

Prouty, Nancy G.; Cohen, Anne; Yates, Kimberly K.; Storlazzi, Curt D.; Swarzenski, Peter W.; White, Darla

2017-12-01

Ocean acidification (OA), the gradual decline in ocean pH and [CO32-] caused by rising levels of atmospheric CO2, poses a significant threat to coral reef ecosystems, depressing rates of calcium carbonate (CaCO3) production, and enhancing rates of bioerosion and dissolution. As ocean pH and [CO32-] decline globally, there is increasing emphasis on managing local stressors that can exacerbate the vulnerability of coral reefs to the effects of OA. We show that sustained, nutrient rich, lower pH submarine groundwater discharging onto nearshore coral reefs off west Maui lowers the pH of seawater and exposes corals to nitrate concentrations 50 times higher than ambient. Rates of coral calcification are substantially decreased, and rates of bioerosion are orders of magnitude higher than those observed in coral cores collected in the Pacific under equivalent low pH conditions but living in oligotrophic waters. Heavier coral nitrogen isotope (δ15N) values pinpoint not only site-specific eutrophication, but also a sewage nitrogen source enriched in 15N. Our results show that eutrophication of reef seawater by land-based sources of pollution can magnify the effects of OA through nutrient driven-bioerosion. These conditions could contribute to the collapse of coastal coral reef ecosystems sooner than current projections predict based only on ocean acidification.