Microbial biomass C and alkaline phosphatase activity in two compost amended soils

Addition of compost from various sources and of different maturity may affect the soil biochemical properties. A field study was conducted to evaluate the effect of different composts, spring-applied alone or in combination with ammonium nitrate (AN), on microbial biomass C (MBC) and alkaline phosphatase activity (APA) in two soils cropped with spring wheat (Triticum aestivum L. 'Messier') in eastern Quebec, Canada. The experiment was conducted in 1994 and 1995 at different sites on a Kamouraska clay (Orthic Humic Gleysol) and a Saint-André sandy loam (Fragic Humo-Ferric Podzol). Treatments included composts at 180 kg N ha−1, composts at 90 kg N ha−1 supplemented with AN, AN at 90 kg N ha−1, and an unfertilized control. Soil MBC and APA were measured 30 d after compost application and at wheat harvest. Additional sampling was made the following spring. Generally, larger MBC and APA values were found at wheat harvest in soils treated with composts alone than with AN alone or unfertilized. These effects were related to soil C content and climatic conditions. Compost type affected soil biochemical properties which could be attributed to the total C supply and material maturation state. Compost addition constitutes an efficient short-term way to promote soil microbial biomass and enzyme activity in cold climates. Key words: Compost, fertilizer, microbial biomass, soil enzyme, wheat

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Microbial and biochemical changes induced by rotation and tillage in a soil under barley production

Canadian Journal of Soil Science ◽

10.4141/cjss93-004 ◽

1993 ◽

Vol 73 (1) ◽

pp. 39-50 ◽

Cited By ~ 94

Author(s):

D. A. Angers ◽

N. Bissonnette ◽

A. Légère ◽

N. Samson

Keyword(s):

Alkaline Phosphatase ◽

Organic Matter ◽

Microbial Biomass ◽

Phosphatase Activity ◽

Alkaline Phosphatase Activity ◽

Soil Layer ◽

Red Clover ◽

Organic C ◽

Top Soil ◽

Total Organic C

Crop rotations and tillage practices can modify not only the total amount of organic matter (OM) in soils but also its composition. The objective of this study was to determine the changes in total organic C, microbial biomass C (MBC), carbohydrates and alkaline phosphatase activity induced by 4 yr of different rotation and tillage combinations on a Kamouraska clay in La Pocatière, Quebec. Two rotations (continuous barley (Hordeum vulgare L.) versus a 2-yr barley–red clover (Trifolium pratense L.) rotation) and three tillage treatments (moldboard plowing (MP), chisel plowing (CP) and no-tillage (NT)) were compared in a split-plot design. Total organic C was affected by the tillage treatments but not by the rotations. In the top soil layer (0–7.5 cm), NT and CP treatments had C contents 20% higher than the MP treatment. In the same soil layer, MBC averaged 300 mg C kg−1 in the MP treatment and up to 600 mg C kg−1 in the NT soil. Hot-water-extractable and acid-hydrolyzable carbohydrates were on average 40% greater under reduced tillage than under MP. Both carbohydrate fractions were also slightly larger in the rotation than in the soil under continuous barley. The ratios of MBC and carbohydrate C to total organic C suggested that there was a significant enrichment of the OM in labile forms as tillage intensity was reduced. Alkaline phosphatase activity was 50% higher under NT and 20% higher under CP treatments than under MP treatment and, on average, 15% larger in the rotation than in the continuous barley treatment. Overall, the management-induced differences were slightly greater in the top layer (0–7.5 cm) than in the lower layer of the Ap horizon (7.5–15 cm). All the properties measured were highly correlated with one another. They also showed significant temporal variations that were, in most cases, independent of the treatments. Four years of conservation tillage and, to a lesser extent, rotation with red clover resulted in greater OM in the top soil layer compared with the more intensive systems. This organic matter was enriched in labile forms. Key words: Soil management, soil quality, organic matter, carbohydrates, microbial biomass, phosphatase

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Ecological Importance of Alkaline Phosphatase Activity in Changing Marine Environmental Conditions

Water ◽

10.3390/w13192750 ◽

2021 ◽

Vol 13 (19) ◽

pp. 2750

Author(s):

Ingrid Ivančić ◽

Romina Kraus ◽

Mirjana Najdek ◽

Stefano Cozzi

Keyword(s):

Alkaline Phosphatase ◽

Phosphatase Activity ◽

Alkaline Phosphatase Activity ◽

Climatic Conditions ◽

Nutrient Loads ◽

Northern Adriatic Sea ◽

Po River ◽

Coastal System ◽

Northern Adriatic ◽

P Limitation

The effects of changing hydrological and climatic conditions on the dynamics of phosphorus (P) were studied in the Northern Adriatic Sea (NA), a coastal system currently affected by these changes. P limitation is one of the key stresses in the NA and it is a globally important phenomenon in aquatic ecosystems. Therefore, the response to P stress by inducing alkaline phosphatase activity (APA) was studied in characteristic water types in the NA, formed by the changing freshwater input in different thermic conditions. APA was important in providing P for microbial growth in upper waters dominated by assimilation during the warmer part of the year in stratified conditions. Contrarily, APA was not important during mixing in the colder part of the year, as well as in waters dominated by regeneration. In waters influenced by freshwater, temperature had no effect on APA, while in high-salinity waters, temperature was an important factor for APA increase. The highest APA occurred during riverine nutrients supply, indicating that the alteration of anthropogenic nutrient loads might strongly change P status in this coastal system. Furthermore, predicted increases in winter sea temperature and summer Po River discharge could delay the water column mixing, prolonging periods of P limitation.

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Contrasting responses of soil phosphatase activity to nitrogen and phosphorus loadings: Implications for phosphorus management

10.5194/egusphere-egu21-1655 ◽

2021 ◽

Author(s):

Ji Chen ◽

Yiqi Luo ◽

Junji Cao ◽

Uffe Jørgensen ◽

Daryl Moorhead ◽

...

Keyword(s):

Microbial Biomass ◽

Phosphatase Activity ◽

Soil Ph ◽

Meta Analysis ◽

Integrated Control ◽

Microbial Biomass C ◽

Nitrogen And Phosphorus ◽

Soil C ◽

P Limitation ◽

Soil Phosphatase

<p>Human activity has caused imbalances in nitrogen (+N) and phosphorus (+P) loadings of ecosystems around the world, causing widespread P limitation of many biological processes. Soil phosphatases catalyze the hydrolysis of P from a range of organic compounds, representing an important P acquisition pathway. Therefore, a better understanding of soil phosphatase activity as well as the underlying mechanisms to individual and combined N and P loadings could provide fresh insights for wise P management. Here we show, using a meta-analysis of 188 published studies and 1277 observations that +N significantly increased soil phosphatase activity by 14%, +P significantly repressed it by 30%, and +N+P led to non-significant responses of soil phosphatase activity. Responses of soil phosphatase activity to +N were positively correlated with soil C and N content, whereas the reverse relationships were observed for +P and +N+P. Similarly, effects of +N on soil phosphatase activity were positively related to microbial biomass C, microbial biomass C:P, and microbial biomass N:P, whereas reverse relationships were observed for +P. Although we found no clear relationship between soil pH and soil phosphatase activity, +N-induced reductions in soil pH were positively correlated with soil phosphatase activity. Our results underscore the integrated control of soil and microbial C, N and P stoichiometry on the responses of soil phosphatase activity to +N, +P, and +N+P, which can be used to optimize future P management.</p>

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LEUCOCYTE METABOLISM IN PREGNANCY

Acta Endocrinologica ◽

10.1530/acta.0.xxxv0575 ◽

1960 ◽

Vol XXXV (IV) ◽

pp. 575-584 ◽

Cited By ~ 2

Author(s):

C. Borel ◽

J. Frei ◽

A. Vannotti

Keyword(s):

Alkaline Phosphatase ◽

Oxygen Consumption ◽

Pregnant Women ◽

Phosphatase Activity ◽

Alkaline Phosphatase Activity ◽

Lactate Production ◽

Glucose Consumption ◽

In Pregnancy

ABSTRACT Enzymatic studies, on leucocytes of pregnant women, show an increase of the alkaline phosphatase activity and a decrease of the glucose consumption and lactate production, as well as of proteolysis. The oxygen consumption, with succinate as substrate, does not vary.

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