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Applying organic amendments with high carbon (C) content can indeed improve soil quality and increase crop yields. The objective of this 4-year field study was to evaluate the effects of three fertilizer-N application (N0, N75, and N100) levels in main plots and five levels of organic amendments incorporation (farmyard manure, poultry manure, press mud, rice straw compost and no manure) in wheat in sub-plots on soil biological properties, and crop yields in a low C sandy loam (Typic Ustochrept) soil. The application of fertilizer-N and organic amendments significantly increased all the soil enzyme activities as compared to the control. In contrast, the results of microbial biomass carbon, phenoloxidase, and peroxidase activity were significantly higher in farmyard manure treated plots by 64.6, 46.2 and 17.7%, respectively than control. Principal component analysis (PCA) suggests that dehydrogenase, xylanase, phenol oxidase, peroxidase and alkaline phosphatase can serve as sensitive indicators and were contribution to soil quality index by 42.5%, 11.3%, 46.8%, 22.6%, and 3.7%, respectively. Results suggest that locally available organic manures can be potential soil amendments to improve biological properties and enhance crop productivity under integrated nutrients management practices in rice-wheat cropping systems. [ABSTRACT FROM AUTHOR]

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The impact of land use and erosion-deposition processes on some physical, chemical, and biological soil properties in a small agricultural catchment in Kursk oblast is analyzed. Plowed Haplic Chernozems and stratozems (Fluvic Chernic Phaeozems (Loamic, Pachic)), as well as unplowed stratozems of a dry valley bottom have been studied. The proportion of large soil aggregates (clods) >10 mm in soils is high on plowed land and low in the dry valley bottom. Differences in the carbon and nitrogen content and in the C/N ratio have not been detected. The analytical pyrolysis has revealed 26 pyrolysates in the composition of soil organic matter (SOM). The relative abundances of pyrrole, pyridine, toluene, and indan among SOM pyrolysates are higher in plowed soils as compared to the soils at the dry valley bottom. Proportions of furfural and methyl furfural among SOM pyrolysates are higher in soils of the dry valley bottom than in plowed soils. Differences in the content of alkanes and phenol are absent. The biomass of microorganisms is mainly formed by fungi (97–99%), and their abundance is greater in soils of the dry valley bottom than in soils of the plowland. Differences in the respiratory activity of the studied soils have not been revealed. The significant influence of erosion-deposition processes and soil cultivation on the spatial heterogeneity of the SOM composition and microbiological parameters is shown. Plowed soils are characterized by the high relative abundance of nitrogen-containing SOM components, while soils at the dry valley bottom have a relatively high abundance of carbohydrate components of mature SOM. The accumulation of fungal biomass and an increase in the structure coefficient in soils of the dry valley bottom indicate the participation of material redeposited from slopes in soil aggregation. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the impact of plant extracts from hemp inflorescences (H10—10% and H20—20%), as well as a mixture of extracts from hemp inflorescences, sage, and tansy leaves (M10—10% and M20—20%) on phytotoxicity and selected physiological and biometric parameters of wheat seedlings, as well as the biological activity of soil in a growth chamber experiment. In all experimental combinations, a low phytotoxicity of the extracts was observed in the form of leaf tip yellowing, classified as first-degree damage or its complete absence. The plant extracts and their mixtures, except for the H20 extract, had an inhibitory effect on the development of fungal pathogens, especially Fusarium spp. The H20 extract increased the fresh and dry weight of root seedlings. The tested extracts also had a positive effect on the chlorophyll content in seedlings. The highest chlorophyll concentrations were recorded for the seedlings sprayed with the M20 extract mixture. The applied plant extracts influenced the activity of soil enzymes. The highest activity of catalase and dehydrogenases was observed after spraying seedlings with M20, while the lowest was recorded after applying H10. Of all the tested groups of soil environment compounds included in the Biolog EcoPlates test, carbohydrates and carboxylic acids were most actively utilized. Conversely, amines and amides constituted the group of compounds utilized the least frequently. The present study demonstrated the high effectiveness of plant extracts on wheat seedlings due to their biocidal action against phytopathogenic fungi and increased biological activity of the soil. This research serves as an initial phase of work, which will aim to verify the results obtained under field conditions, as well as assess the biological stability of the extracts. [ABSTRACT FROM AUTHOR]

Conservation tillage (CT) is a ploughless tillage with a reduced number of operations, and its positive effect on soil functions and health is widely known. Multivariate analyses are required to choose indicators that adequately characterize the changes in soil health. However, there is little research on the comprehensive analysis of the full spectrum of soil physical, chemical and biological properties. Therefore, we examined 21 soil parameters in a long-term CT experiment conducted in Hungary. Four pairs of similarly sized CT and conventional ploughing tillage (PT) plots were set up in 2003 on Luvisols. The soil samples were collected after 17 years. The total organic carbon (TOC) increased significantly in the 0-15 cm layer at CT sites compared to those in PT, indicating a total increase of 5.22 tha-1 TOC stock. In addition, the increasing biological activity and improved soil structure were the most important processes at the CT sites. Furthermore, more complex humic substances with higher molecular weights are characteristic of water-extractable organic matter (WEOM) as a result of CT. The potentially available nitrogen, phosphorus and potassium were also measured with a relatively high response ratio. Slowly changing parameters, such as cation exchange capacity and base saturation, are important soil physical and chemical parameters, but are not good indicators of the impact of tillage practices. Based on principal component analysis, we suggest the use of water-extractable organic C, amino-nitrogen, water-stable aggregates, available P and K and photometric analysis of WEOM to identify the soil improving processes. [ABSTRACT FROM AUTHOR]

Purpose: Exogenous Organic Matter (EOM) enriches and regenerates the soil, while solving the problem of landfilling waste such as sewage sludge and bottom sediments. The main purpose of the presented study was to estimate the influence of type and dosage of applied EOM on soil biological characteristics and supporting plant growth, with consideration of inoculation with PGPR (plant growth-promoting rhizobacteria). Materials and methods: The soil samples were characterized by measuring key enzyme activities, determining the community-level physiological profiling (CLPP) using Biolog EcoPlates, abundance of microorganisms and evaluation physical and chemical properties. Results and discussion: Application of EOM mostly increased enzyme activity as well as overall metabolic activity compared to control sample. Increasing the dose of poultry manure and sewage sludge from 20 to 40 t ha−1 increased dehydrogenase, acid and alkaline phosphatase activity. Moreover, the addition of EOM affected the metabolic activity and the number of selected groups of bacteria and fungi. Conclusions: In the research it was proven that application of EOM leads to relatively rapid and positive changes in soil biological activity. The research also confirmed that the supporting factor for plant growth was the inoculation with PGPR bacteria. This approach, together with the reuse of organic wastes may become an attractive approach in sustainable cropping systems in a circular economy system. [ABSTRACT FROM AUTHOR]

In rice–wheat agro-ecosystems, crop residue burning and intensive tillage practices are conventional methods of agriculture in India which deteriorates soil and environmental quality. Present study investigated the individual impact of crop residue burning and excessive tillage as well as combined impact of both practices on soil biological parameters such as organic carbon (SOC), microbial biomass carbon (MBC), soil respiration rate, Bradford reactive soil protein (BRSP), nitrogen mineralization rate and microbial community structure at two soil depths 0–15 and 15–30 cm. Four different burning-tillage combination treatments: no-burn-no-tillage (NBNT); no-burn + tillage (NB + T); after-burn-no-tillage (ABNT) and after-burn + tillage (AB + T) were studied. The microbial community structure was investigated by phospholipids fatty acid analysis (PLFA). Results indicated that crop residue burning and tillage pose significant impact on soil biological parameters and soil microbial community especially at surface soil (0–15 cm). ABNT treatment posed a profound reduction in MBC and soil respiration rate by 54% and 34%, with respect to NBNT. Likewise, a reduction in BRSP content and SOC by 14% and 4% was noticed, while nitrogen mineralization rate enhanced by 19% in ABNT treatment. NB + T treatment significantly (P ≤ 0.05) reduced nitrogen mineralization rate, MBC and BRSP content by 58%, 48% and 25% respectively with respect to NBNT. AB + T treatment remarkably reduced MBC, SOC and BRSP content by 38%, 31% and 23% with respect to NBNT. Principal component analysis indicated that stubble burning and tillage induced a variation in soil microbial communities by ~ 61% and 23%, respectively. From our results, it can be inferred that, no burn and no tillage is the ecologically sustainable agricultural practice for maintaining the soil biological characteristics of the rice–wheat agro-ecosystems of India. [ABSTRACT FROM AUTHOR]

Chicken manure and composts derived from it are valuable organic fertilizers that have a positive impact on soil fertility and significantly enhance crop yields. However, the application of fresh manure can lead to excessive concentrations of nitrogen and other nutrients in the soil, as well as contamination of the soil with microorganisms that are pathogenic to humans and animals. Therefore, it is recommended to compost chicken manure prior to its use in agriculture. This review examines the composition and properties of chicken manure, the techniques involved in its composting, and its influence on the physical, chemical, and biological properties of the soil. The utilization of composted manure results in increased levels of organic carbon (on average by 1–1.5%), nitrogen (by 0.1–0.2%), and other biophilic elements. Moreover, it improves various physical properties of the soil, such as porosity, aeration, and density. Levels of pH increase (by 0.2–0.4), as well as electrical conductivity (by 2–2.5 times), and the quantity of water-resistant aggregates (by 5–10%). The application of these fertilizers also promotes biological activity, microbial diversity, microbial biomass carbon (by 25–75%), and soil enzymatic activity (phosphatase and catalase increase by 5–7 times, and urease by 3–5 times). When chicken manure is incorporated into the soil, a significant (2–4 times) increase in the population of bacteria from the phyla Firmicutes, Bacteroidetes, and Actinobacteria is observed. The necessity of investigating the effects of compost derived from chicken manure on the chemical composition and storage of soil organic matter, pore space, and the ecotrophic structure of the soil microbiome is also discussed.

Treated bio-residues can be used as biostimulants in crops within the circular economy approach to reduce the use of traditional fertilisers. In this work, we optimised the combination rates for three types of treated bio-residues (compost, biochar, and anaerobic digestate (AD)) in two microcosm trials, one with a combination of compost and biochar and other with biochar and AD. The crop used was maize, and the variables analysed were plant growth, and soil chemical and biological properties. The combination of bio-residues improved plant growth and soil biological activity to a greater extent than one product alone; that is, compost and biochar performed better than compost alone and biochar, and AD performed better than biochar alone. However, while the concentration in the plant biomass of several essential nutrients for crops increased in the treatments with compost and biochar, and with biochar and AD, compared to the untreated controls, the nitrogen concentration was reduced. This was due to the competition for nitrogen between the plant and the soil microbiome, whose activity was activated. Due to the importance of nitrogen in plant growth, the increase in biomass production could be explained not only by the higher availability of other nutrients but also by the plant-growth-promoting activity exerted by the more active soil microbiome. Further research should focus on validating this hypothesis and unravelling the mechanisms involved. From the environmental site, the presence of biochar in the mixtures of organic residues reduced the soil nitrogen at risk of lixiviation and sequestered carbon, which partially compensated for the increased CO2 emissions because labile forms of carbon were present in the remaining organic residues. [ABSTRACT FROM AUTHOR]

Urban soil is often compacted during anthropogenic activities, which presents a challenging substrate for tree growth. Two techniques for decompacting soils (air spading and vertical mulching) were evaluated alone and in combination with the soil amendment biochar and/or a woodchip mulch. Effects on soil quality (bulk density, organic matter, vegetation ground cover, cotton strip degradation, root dry mass, and earthworm counts) were monitored over 5 years. A combined treatment of air spading, biochar, and a woodchip mulch layer proved optimal in improving the soil quality of a heavily compacted soil over the 5-year period. This treatment was, however, the most expensive and time-consuming. A woodchip mulch was the most effective of the individual treatments and the most cost-effective. Air spading alone proved reasonably effective in improving soil quality over the 5-year study period. Effects of air spading could be improved by addition of a woodchip mulch. Vertical mulching alone or in combination with biochar had little influence on soil quality over 5 years. Results demonstrated that effective long-term soil decompaction measures exist for arborists to improve compacted soils. [ABSTRACT FROM AUTHOR]

Understanding the physicochemical and biological parameters of coastal soilsisessential for developing climate-resilient and sustainable resource management strategies. A study was conducted to assess the characteristics of the coastal sandy soils in Thiruvananthapuram district (Agro-ecological unit 1-Southern Coastal Plains), Kerala. Fifty geo-referenced surface soil samples along with surface core samples were collected during March 2022 from the Thiruvananthapuram district which falls under the southern coastal plains covering an area of 19,344 ha. The analytical results for soil physical properties showed that the bulk density was in the range of 1.37 - 1.86 Mg m-³ while particle density was2.22 - 2.89 Mg m-³, with 22.7 - 56.0%water holding capacity, and the soilscame under sand and loamy sand textural classes. The soil chemical properties were found to be in the range of 5.11 - 7.19 for pH and 0.03 - 0.23 dS m-1 for electrical conductivity. Organic carbon was found to be in the range of 0.07 - 1.01%, nitrogen 100 - 308kg ha-1, phosphorus 7.05 - 59.94 kg ha-1 and potassium 100 - 361 kg ha-1. Secondary minerals were found to be present in the range: calcium 80 - 360 mg kg-1, magnesium 47 - 152 mg kg-1 and sulphur 4.5 - 20.5 mg kg-1. Boron was found to be in the range of 0.11 - 0.82 mg kg-1. Soil biological activity in these coastal sandy soils was poor with dehydrogenase activity in the range of 5.57 - 20.96µg TPF hydrolysed g-1 soil 24 h-1. Hence, these soils require site-specific nutrient management strategies including organic manure application to fully utilize their potential for sustainable agriculture. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate the efficiency of organic carbon sequestration (ESCS) in a topsoil of the typical slightly eroded chernozem under application of bioformulations based on Trichoderma viride and Pseudomonas aureofacieens with crop byproducts alone or in combination with nitrogen as well as its correlation with indicators of transformation of plant residues and soil biology. The study focused on the typical slightly eroded heavy loamy chernozem on carbonate loess–like loams with a topsoil content of humus (after Tyurin) of 5.11–5.36%; of alkaline hydrolysable nitrogen of 160.2 ± 2.6 mg/kg; mobile phosphorus and potassium (after Chirikov) of 112 ± 7.8 mg/kg and 102.2 ± 9.8 mg/kg, respectively; and of exchange calcium of 223.5 ± 2.2 mg–eq./kg with the medium close to neutral (pHKCl 5.6 ± 0.1. The research was carried out in a grain cover- and row crop rotation (sunflower–barley–soybean–buckwheat) in a stationary field experiment with bioformulations in Kursk oblast in 2018–2021. The experimental design included the following variants: chopped byproducts (background) as a control; background + ammonium nitrate at a rate of 10 kg of primary nutrient nitrogen (N) per ton of byproducts (background + nitrogen), treatment of seeds with the bioformulations Gribofit (G) 2 L/ha and Imunazot (I) 3 L/ha + preparation of soil before sowing using the bioformulations (3 L/ha of G + 2 L/ha of I) + treatment of the sowed area with the bioformulations (3 L/ha of G + 2 L/ha of I) twice during the growing season + treatment of crushed byproducts after harvesting with the bioformulations (5 L/ha of G + 3 L/ha of I) before incorporating into the soil (background + bioformulations); and background + bioformulations + nitrogen. The efficiency of organic carbon sequestration in the soil was calculated according to the formula proposed by the authors based on the study of dynamics of humus reserve in the topsoil, annul input of crushed byproducts into the soil, and content of postharvest root and above-ground crop residues in the soil. It was found that the use of bioformulations and chopped byproducts contributed to an increase in ESCS in the topsoil 3.7-fold, the combined use of bioformulations with nitrogen 4.9-fold, and the application of nitrogen alone 2.3-fold compared with the control. The efficiency of organic carbon sequestration in the soil proved to have very close correlation with a mean rate of decomposition of plant residues (r = 0.98), close with CO2 emission from the soil (r = 0.88), and moderate with the cellulolytic activity of the soil (r = 0.69). [ABSTRACT FROM AUTHOR]

The number of soil microorganisms affect the fertility of the soil and the processes occurring in the soil microflora. An urgent research problem is the rationale for the use of intensive technologies for the cultivation of sweet corn using progressive methods for obtaining a highly productive crop based on the principles of resource conservation, biologization and ecologization. The purpose of the research is to study the toxicity and biological activity of the soil after sowing sweet corn. The tasks are to determine the biological activity and toxicity of the soil, and comparative impact of agricultural practices in the study of soil toxicity. Two-factor experiment in quadruple repetition. The experiments were carried out on the farm enterprise of Popov S.A., the Chernoyarsky district of the Astrakhan region. The research period was 2009…2015. Determination of biological activity and toxicity was carried out at the beginning of the research in 2009 and 2015. According to the assessment of the intensity of the destruction of cellulose on O.E. Pryazhnikova’s scale biological activity was characterized as strong. A close correlation dependence on experience factors was noted, the relationship between the signs was high and direct. When determining the toxicity of the soil, we came to the conclusion that at the beginning of the research favorable conditions for the development of the studied crop were formed on soils cultivated by moldboard cultivation. According to zero tillage, an increase in soil toxicity was observed, which was expressed in a decrease in seed germination, the mass of seedlings. Revisited in 2015. Soil toxicity after zero tillage decreased in all variants, seed germination increased, on average, by 5...8%. As a result of the accumulation of plant residues on the soil surface, an upper humus layer was formed, leading to a constant penetration of ai r into the soil.

A model laboratory experiment on arable soil with low organic content and low biological activity showed short-term changes in the intensity of the main microbiological processes of the nitrogen transformation in soil after the application of glyphosate. The soil incubation with glyphosate at the maximum recommended dose of 8 L/ha for 22 days resulted in an increase in nitrogen-fixing and denitrifying activities by 30–80 and 300%, respectively, and in a decrease in nitrification by 20–40%. These effects were of a short-term nature and did not reflect the entire complex of ongoing microbiological processes. Glyphosate had no effect on the CO2 emission, an integral indicator of biological activity. At the end of incubation period, the soil with glyphosate was characterized by an increase in the number of bacteria by 40% and a decrease in the number of micromycetes by 70%. In general, under the selected conditions, the application of glyphosate led to a well-pronounced deterioration in the biological activity of the soil. The multisubstrate test showed that the application of glyphosate leads to an increase in the value of the coefficient of rank distribution of substrate utilization spectra (d) accompanied by a decrease in the specific metabolic activity (W) and the integral vitality index (G). It was shown for the first time that application of the glyphosate for the soil with a low biological activity and phosphorus availability, and the herbicide degradation with a break in the C–P bond excluding the formation of toxic metabolites have a pronounced negative effect on soil microorganisms, which leads to inhibition of wheat plant growth. [ABSTRACT FROM AUTHOR]

Accelerating land-use change (LUC) in the Nilgiri Hill Region (NHR) has caused its land to mortify. Although this deterioration has been documented, the destruction of buried gem soil has not been reported. Therefore, this study was conducted to assess the impact of LUC on soil-carbon dynamics in the six major ecosystems in the NHR: croplands (CLs), deciduous forests (DFs), evergreen forests (EFs), forest plantations (FPs), scrublands (SLs), and tea plantations (TPs). Sampling was conducted at selected sites of each ecosystem at three depth classes (0–15, 15–30, and 30–45 cm) to quantify the carbon pools (water-soluble carbon, water-soluble carbohydrates, microbial biomass carbon, microbial biomass nitrogen, dehydrogenase, and different fractions of particulate organic carbon). We found that the LUC significantly decreased the concentration of carbon in the altered ecosystems (49.44–78.38%), with the highest being recorded at EF (10.25%) and DF (7.15%). In addition, the effects of the LUC on the aggregate size of the organic carbon were dissimilar across all the aggregate sizes. The relatively high inputs of the aboveground plant residues and the richer fine-root biomass were accountable for the higher concentration of carbon pools in the untouched EFs and DFs compared to the SLs, FPs, TPs, and CLs. The results of the land-degradation Index (LDI) depicted the higher vulnerability of TP (−72.67) and CL (−79.00). Thus, our findings highlight the global importance of LUC to soil quality. Henceforth, the conservation of carbon pools in fragile ecosystems, such as the NHR, is crucial to keep soils alive and achieve land-degradation neutrality. [ABSTRACT FROM AUTHOR]

Common fertilizers present a low use efficiency caused by nutrient losses (e.g., through leaching, volatilization, adsorption, and precipitation in solution as well as through microbial reduction and immobilization) that create a significant limiting factor in crop production. Inoculation with Plant Growth-Promoting Bacteria (PGPB) is presented as an alternative to increasing fertilizer efficiency. The goal of the study was to test the hypothesis that PGPB (solution with Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, and Bacillus pumilus) can be a strategy to increase the monoammonium phosphate (MAP) efficiency, root growth, and nutrient assimilation of soybean and corn cultivated in arenosol and oxisol. A greenhouse study was developed with the rates of PGPB (rates: 0, 1, 1.33, and 1.66–2.0 L per ton of fertilizer) sprayed on MAP and applied in an arenosol and oxisol cultivated with soybean and corn. Results showed that in both soils and crops, there was a variation in soil biological activity during the experiment. On day 45, PGPB + MAP promoted the beta-glucosidase and ammonium-oxidizing microorganism activities in the arenosol. The PGPB + MAP increased crop root growth in both soils and crops. Plant dry matter was associated with the phosphorous content in the soil, indicating that the phosphorous applied was absorbed by the plants, consequently resulting in a higher accumulation in the plant. Based on the results, the conclusion is that PGPB + MAP increases the growth and phosphorous accumulation of soybean and corn cultivated in the arenosol and oxisol, with a direct effect on crop rooting. [ABSTRACT FROM AUTHOR]

Many petroleum extraction and refinement plants are located in arid climates. Therefore, the remediation of petroleum-polluted soils is complicated by the low moisture conditions. We ran a 70-day experiment to test the efficacy of various combining of remediation treatments with sorghum, yellow medick, and biochar to remove petroleum from and change the biological activity of Kastanozem, a soil typical of the dry steppes and semideserts of the temperate zone. At normal moisture, the maximum petroleum-degradation rate (40%) was obtained with sorghum–biochar. At low moisture, the petroleum-degradation rate was 22 and 30% with yellow medick alone and with yellow medick − sorghum, respectively. Biochar and the biochar-plant interaction had little effect on soil remediation. Both plants promoted the numbers of soil microbes in their rhizosphere: yellow medick promoted mostly hydrocarbon-oxidizing microorganisms, whereas sorghum promoted both hydrocarbon-oxidizing and total heterotrophic microorganisms. Low moisture did not limit microbial development. In the rhizosphere of sorghum, dehydrogenase and urease activities were maximal at normal moisture, whereas in the rhizosphere of yellow medick, they were maximal at low moisture. Peroxidase activity was promoted by the plants in unpolluted soil and was close to the control values in polluted soil. Biochar and the biochar-plant interaction did not noticeably affect the biological activity of the soil. [ABSTRACT FROM AUTHOR]

Reforestation has long been the best practice to restore degraded forests due to human interventions. In this paper we investigated the effect of forest degradation (DNF) along with reforestation using 4 endemic species (Alnus subcordata, ASP; Acer velutinum, AVP; Cupressus sempervirens, CSP; Quercus castaneifolia Mey, QCP) on forest’s soil chemical and biological indicators compared to a close-to-virgin natural forest (VNF). For this study, a total of 24 physico-chemical and 25 biological and microbial indicators were measured in soils of all 6 forest stands along with the litter properties. Results showed that the lowest soil quality was observed under DNF, CSP, and QCP which was the result of forest cover degradation in DNF and low litter quality, especially low pH and high C:N, in CSP and QCP. Soil fauna communities were significantly affected by tree species. We found two times higher density of earthworms in VNF compared to ASP, but in DNF the density was 5 times lower than VNF. We found no epigeic earthworms in QCP, CSP and DNF and no endogeic earthworms in DNF. Acarina and Collembola density was high in VNF and ASP, but they showed significant differences (VNF>ASP), and their density sharply decreased in other stands, especially in CSP (3 times lower than VNF) and DNF (8 to 10 times lower than VNF). Nematode density was statistically equal in VNF, ASP, and AVP, but significantly lower in other stands. Protozoa, bacteria and fungi densities were significantly higher in VNF and ASP (VNF>ASP) compared to each other and other forest stands. Basal respiration, substrate induced respiration, microbial biomass N and P, and carbon availability index was also higher in VNF and ASP compared to other stands. Although VNF has the best condition because of old forest cover and high diversity, ASP soil showed significant improvements, demonstrating the importance of litter quality in soil restoration. Restoration effectiveness ranking of the four tested species on soil improvement are therefore ASP>AVP>QCP>CSP. The significant improvement of soil quality under ASP compared to other reforestated stands, only after 3 decades, emphasizes the importance of tree species selection and litter quality on soil chemical and biological restoration.

In the current agronomic context, the adoption of alternative forms of soil management is essential to increase crop yield. Agricultural sustainability requires practices that generate positive impacts and promote an increase in microbiome diversity as a tool to overcome adverse environmental conditions. An important ally is the indigenous arbuscular mycorrhizal fungi (AMF) that can improve plant growth and provide protection against abiotic stress such as metal toxicity. In a greenhouse experiment, this work studied the effect of wheat growth on several parameters of biological activity and functional microbiome in relation to wheat antecedent plant mycotrophy and soil disturbance under Mn stress. When the wheat was planted after highly mycotrophic plants and the soil was not previously disturbed, the results showed a 60% increase in wheat arbuscular colonization and a 2.5-fold increase in dry weight along with higher values of photosynthetic parameters and dehydrogenase activity. Conversely, soil disturbance before wheat planting increased the β-glucosidase activity and the count of manganese oxidizers, irrespectively of antecedent plant, and decreased drastically the wheat dry weight, the AMF colonization and the chlorophyll content compared to the undisturbed treatment. These findings suggest that not only the wheat growth but also the soil functional microbiome associated is affected by the antecedent type of plant and previous soil disturbance imposed. In addition, the improvement in wheat dry weight despite Mn toxicity may rely on shifts in biological activity associated to a well-established and intact ERM early developed in the soil. [ABSTRACT FROM AUTHOR]

Lead (Pb) is one of the most hazardous heavy-metal pollutants in the environment. However, the resistance of different soils and ecosystems to Pb pollution varies greatly. In the present study, the comparative assessment of the resistance to Pb contamination in the forest, forest-steppe, steppe, and mountain-meadow soils of the Central Ciscaucasia and the Caucasus regions was conducted. There were 10 types and subtypes of objects from the forest, forest-steppe, steppe, and mountain-meadow soils which were selected for this study. The laboratory modeling of the effect of chemical soil contamination with lead (II) oxide (PbO) at different concentrations, 100, 1000, and 10,000 mg/kg, were introduced into the soil to check the microbiological, biochemical, and phytotoxic properties of the soil after 30 days of incubation. Soil resistance to Pb stress was assessed by the degree of the decrease in the most sensitive and informative biological indicators of the soil condition. It has been found that the forest-steppe and steppe soils showed a greater resistance than that of the forest and mountain-meadow soils. The regional maximum permissible concentration (rMPC) of Pb was developed for the first time, according to the degree of violation of the ecosystem functions of the soils. The forecast maps were developed for the deterioration of the soil condition during the Pb contamination at variable concentrations in the Central Ciscaucasia and the Caucasus regions. [ABSTRACT FROM AUTHOR]

The current paper has presented the results of long-term experiments on the study of the biological activity of sod-podzolic soil by the application method in field crop rotations. The experimental part of the work was carried out on the experimental plots of the Mari Research Institute of Agriculture, a branch of the FSBSI FARC of the North-East in 1996–2020. The trials were laid down in 1996 and 1998. The trial was laid down in two factors. Factor A included such types of crop rotations as grain-grasses crop rotations (oats + clover, clover of 1 year of use, winter crops, vetch-oat mixture for grain, spring wheat, barley as a control grain crop); the first rotation of crops (annual leguminous grasses, winter crops, barley, potatoes, vetch-oat mixture for grain, spring wheat); the second rotation of crops (vetch-oat mix[1]ture for grain, spring wheat, potatoes fertilized with manure (80 t/ha), barley + clover, clover of 1 year of use, winter crops); the third rotation of crops (barley + clover, clover of 1 year of use, clover of 2 years of use, winter crops, pota[1]toes, oats). Factor B included application of mineral fertilizers: control grain crop (without fertilizers); N60P60K60. There has been established that the activity of soil microflora mainly depended on the presence of organic matter in the soil. The largest activity of cellulose-destroying microorganisms against a natural background of fertility was identified in the second rotation of crops, with the introduction 23.9% of manure for potatoes in the first period (45 days) and 54.7% in the second period (90 days) of exposure. The slightest biological activity of the soil was identified in the grain-grasses crop rotation (with 83% of grain crops); it was 17.7% in the first 45 days and 43.4% in the second period of exposure. That was caused by the deficit of organic matter. The introduction of mineral fertilizers in a dose of N60P60K60 under pre-sowing tillage significantly increased the soil biological activity in comparison to the unfertilized background, and a fairly high intensity of flax decomposition was observed in the second rotation of crops with 24.9% in 45 days and 56.8% in 90 days. Correlation analysis (1998-2019) between the mean flax decomposition under crops for the entire vegetation period and the value of the hydrothermal coefficient (HThC) showed a close direct correlation, which in the first and second periods of exposure was 0.87–0.90 and 0.86–0.89, respectively.

Remediation of crude oil-impacted areas is a major pervasive concern in various environmental conditions. The major aim of this study was to investigate the collaboration of vetiver grass (Vetiveria zizanioides L.) and petroleum hydrocarbon-degrading bacteria to clean up contaminated soils. Vetiver grass and five native bacterial isolates were used in one consortium to remediate contaminated soil by crude oil at various concentrations (2.0, 4.0, 6.0 8.0, 10, and 12.0% woil/wsoil). The presence of isolated bacteria caused a significant (p < 0.05) increment of root-shoot ratio of vetiver in contaminated soils in comparison to non-contaminated soil. The combination of vetiver and bacterial consortium revealed efficient dissipation of more than 30% of low-molecular-weight polycyclic aromatic hydrocarbons (PAHs) and more than 50% of high-molecular-weight PAHs in all crude oil concentrations. The removal of n-alkanes in the simultaneous presence of the bacteria and plant was more than 70.0% at 10.0% of oil concentration, whereas the removals in control were 20.7, 13.7 and 9.2%, respectively. The hydrocarbons dissipation efficiency of applied treatments decreased at 12.0% of contamination. It is concluded that a combination of vetiver grass and the isolated bacteria could be a feasible strategy for remediation of crude oil-polluted soils. Novelty statement Determination of the responses of vetiver grass under different crude oil concentrations is one of the novelties of the present study, which is helpful for demonstrating plant tolerance on polluted environments. Also, it adds information about the potential of this grass to clean up crude oil-polluted soils solely as well as in the presence of promising selected bacterial strains. [ABSTRACT FROM AUTHOR]

Common fertilizers present a low use efficiency caused by nutrient losses (e.g., through leaching, volatilization, adsorption, and precipitation in solution as well as through microbial reduction and immobilization) that create a significant limiting factor in crop production. Inoculation with Plant Growth-Promoting Bacteria (PGPB) is presented as an alternative to increasing fertilizer efficiency. The goal of the study was to test the hypothesis that PGPB (solution with Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, and Bacillus pumilus) can be a strategy to increase the monoammonium phosphate (MAP) efficiency, root growth, and nutrient assimilation of soybean and corn cultivated in arenosol and oxisol. A greenhouse study was developed with the rates of PGPB (rates: 0, 1, 1.33, and 1.66–2.0 L per ton of fertilizer) sprayed on MAP and applied in an arenosol and oxisol cultivated with soybean and corn. Results showed that in both soils and crops, there was a variation in soil biological activity during the experiment. On day 45, PGPB + MAP promoted the beta-glucosidase and ammonium-oxidizing microorganism activities in the arenosol. The PGPB + MAP increased crop root growth in both soils and crops. Plant dry matter was associated with the phosphorous content in the soil, indicating that the phosphorous applied was absorbed by the plants, consequently resulting in a higher accumulation in the plant. Based on the results, the conclusion is that PGPB + MAP increases the growth and phosphorous accumulation of soybean and corn cultivated in the arenosol and oxisol, with a direct effect on crop rooting.

The coastal ecosystem is one of the most fragile ecosystems to climate change. Soil salinization in these ecosystems due to climate change-induced sea-level rise could be a major threat and constraint to agricultural production. Thus, assessing the soil quality of these soils using a suitable indexing method can help to decide the countermeasures for their sustainable utilization. The present study aimed to evaluate the soil quality of the salt-affected soils in the coastal region of India using different soil quality indexing methods. The soil quality indices (SQIs) were developed using two scoring methods: linear and non-linear of the minimum dataset and weighted approach. Based on electrical conductivity (EC1:2.5, EC in 1:2.5 soil to water ratio), the soils were categorized into five classes as non-saline, slightly-saline, moderately-saline, strongly-saline, and very strongly-saline. The soil salinity impacted the soil's physical, chemical, and biological properties significantly. Using principal component analysis and correlation, a minimum dataset comprising of eight soil properties namely basal soil respiration, urease enzyme activity, EC, soil available copper, zinc, boron, iron and soil pH was identified. The overall performance of the weighted SQIs developed using non-linear scoring was better than linear scoring. The weighted SQI developed using non-linear scoring (SQINLW) revealed that the class non-saline had the highest soil quality values and the very strongly saline the lowest. The SQINLW correlated strongly with the EC1:2.5 (r = 0.96; p < 0.05). The SQINLW for salinity classes was in order as non-saline > moderately saline = slightly saline > strongly saline > very strongly saline and thus, the SQINLW could be used as an effective tool to assess the soil quality of salt-affected soils of the coastal region. The correlation analysis between the SQIs and grain yield for different salinity classes revealed significant (p < 0.01) and the highest values of correlation coefficient in the SQINLW (r = 0.67–0.74, p < 0.01). The urease enzyme activity (35.1–66.6%) and EC (10.1–40.6%) contributed the most to the SQINLW and thus emphasizes the importance of these properties while assessing the soil quality of salt-affected soils. The soil quality indexing approach (non-linear scoring and weighting of a minimum dataset) identified in the study could reduce cost and save time and be a good guide for growers, land managers, extension specialists and policy or decision-makers for its utilization. [ABSTRACT FROM AUTHOR]

Toxicological effects of herbicides on the non-target microorganisms in the soil that play important roles in degrading organic matter, nutrient cycling, and decomposition should be considered if they were applied at higher concentrations. This study was conducted to reveal the toxicity of three modern herbicides (dicamba + tritosulfuron; DT, isoxinutole + thlencarbuone-methyl + cyprosulfamide; ITC and nicosulfuron; N) on soil carbon mineralization for short term. Recommended concentration (25 g/day for DT1, 30 ml/day for ITC1, and 125 ml/day N1), its 5 (DT5, ITC5, and N5), and 10 (DT10, ITC10, and N10) folds of herbicides were applied on a clay soil with no pesticide application history. Soil + herbicide mixes and soil without herbicide as control were incubated under constant temperature (28 °C) and moisture (80% of soil field capacity) for 42 days. In general, all doses of herbicides were significantly decreased soil carbon mineralization in short term (P < 0.05). Cumulative carbon mineralization was declined for 3.4% by DT1, for 15.0% by DT5, for 22.4% by DT10, for 13.7% by ITC1, for 14.2% by ITC5, for 18.6% by ITC10, for 4.7% by N1, for 10.0% by N5, and for 21.0% by N10, respectively, compared to control. Significant decreases were observed in the rates of carbon mineralization except DT1 and N1. Results suggested that higher doses of these herbicides negatively affected on soil microbial respiration. [ABSTRACT FROM AUTHOR]

In the current agronomic context, the adoption of alternative forms of soil management is essential to increase crop yield. Agricultural sustainability requires practices that generate positive impacts and promote an increase in microbiome diversity as a tool to overcome adverse environmental conditions. An important ally is the indigenous arbuscular mycorrhizal fungi (AMF) that can improve plant growth and provide protection against abiotic stress such as metal toxicity. In a greenhouse experiment, this work studied the effect of wheat growth on several parameters of biological activity and functional microbiome in relation to wheat antecedent plant mycotrophy and soil disturbance under Mn stress. When the wheat was planted after highly mycotrophic plants and the soil was not previously disturbed, the results showed a 60% increase in wheat arbuscular colonization and a 2.5-fold increase in dry weight along with higher values of photosynthetic parameters and dehydrogenase activity. Conversely, soil disturbance before wheat planting increased the β-glucosidase activity and the count of manganese oxidizers, irrespectively of antecedent plant, and decreased drastically the wheat dry weight, the AMF colonization and the chlorophyll content compared to the undisturbed treatment. These findings suggest that not only the wheat growth but also the soil functional microbiome associated is affected by the antecedent type of plant and previous soil disturbance imposed. In addition, the improvement in wheat dry weight despite Mn toxicity may rely on shifts in biological activity associated to a well-established and intact ERM early developed in the soil.

Lead (Pb) is one of the most hazardous heavy-metal pollutants in the environment. However, the resistance of different soils and ecosystems to Pb pollution varies greatly. In the present study, the comparative assessment of the resistance to Pb contamination in the forest, forest-steppe, steppe, and mountain-meadow soils of the Central Ciscaucasia and the Caucasus regions was conducted. There were 10 types and subtypes of objects from the forest, forest-steppe, steppe, and mountain-meadow soils which were selected for this study. The laboratory modeling of the effect of chemical soil contamination with lead (II) oxide (PbO) at different concentrations, 100, 1000, and 10,000 mg/kg, were introduced into the soil to check the microbiological, biochemical, and phytotoxic properties of the soil after 30 days of incubation. Soil resistance to Pb stress was assessed by the degree of the decrease in the most sensitive and informative biological indicators of the soil condition. It has been found that the forest-steppe and steppe soils showed a greater resistance than that of the forest and mountain-meadow soils. The regional maximum permissible concentration (rMPC) of Pb was developed for the first time, according to the degree of violation of the ecosystem functions of the soils. The forecast maps were developed for the deterioration of the soil condition during the Pb contamination at variable concentrations in the Central Ciscaucasia and the Caucasus regions.

• Thinning exerted positive effects on soil microbial biomass. • Thinning significantly increased soil saccharase and urease activity. • Moderate thinning intensity optimizes soil microbial activity. • Long-term recovery is more conducive to improving soil microbial activity. • Increases in precipitation and temperature seemingly hinder microbial activity. Forest thinning is a management measure intended to promote forest regeneration and improve soil microbial activity. However, a comprehensive evaluation of the effects of forest thinning on soil microbial biomass and enzyme activity is yet to be conducted. Therefore, this study analyzed 1059 data points from 69 studies at the global scale to investigate the effects of forest type, thinning intensity, recovery time, and mean annual precipitation and temperature on microbial biomass and enzyme activity. Thinning significantly increased the microbial biomass carbon (8.92 %), nitrogen (17.40 %), and phosphorus (29.98 %) levels and saccharase (9.21 %) and urease (10.08 %) activities. The response ratio of soil microbial biomass was higher in coniferous forests than that in broadleaf or mixed forests, and the response ratio of saccharase activity was higher in mixed forests than in coniferous or broadleaf forests. The response ratios of microbial biomass and phosphatase activity were higher in the late recovery time than those in the early and medium recovery times. Soil microbial biomass and enzyme activity first increased and then decreased with thinning intensity but decreased with mean annual precipitation and temperature. In conclusion, this study highlights that thinning significantly increases soil microbial biomass and enzyme activity, and a moderate thinning intensity (33.3–66.6 %) and long-term recovery (>10 years) are highly conducive to improving soil microbial activity. These results provide a basis for forest ecosystem management and the formulation of scientific and reasonable thinning parameters. [ABSTRACT FROM AUTHOR]

European abandoned lands have been increasing in recent decades, and this is occurring in a climate change scenario in which the consequences of their interactions are still little known. We tested the hypothesis that the functionality of abandoned lands responds differently to year‐to‐year climate variations depending on the time since the cessation of agricultural activity. We constructed a chronosequence in Mediterranean abandoned vineyards at six different years of abandonment in 2016 (1, 3, 7, 11, 25, 40), in a current vineyard and in land not dedicated to vineyards. Soil total organic carbon (TOC), total nitrogen (TN) and available nutrients, enzyme activities relating to the main macronutrient cycles and plant‐community attributes were studied at 24 sites over three consecutive years. A total of 144 samplings were performed. TOC, TN, most enzyme activities and plant species density increased throughout the chronosequence, although interannual climate variability also had a significant influence. The extreme drought event increased the activity of enzymes related to the carbon (C) and nitrogen (N) cycle, as well as the stock of TOC after a subsequent decrease in TOC when environmental conditions became favourable. In contrast, plant species density and the cover of certain plant functional traits such as mycorrhizal symbiotic plants (Cistaceae) and N‐fixers (Fabaceae) decreased significantly. Our results also demonstrated that extreme drought events had a higher negative impact on lands that had been abandoned for longer. We therefore conclude that extreme drought events damage the functionality of Mediterranean abandoned agrosystems, thus affecting all its compartments and jeopardising its functionality. [ABSTRACT FROM AUTHOR]

This paper describes typical and humic petrozem soils developing in the most high-altitude (goltsy) zone of the Khibiny Mountains under three predominant types of primitive plant communities representing different stages of the primary succession. The profiles of such soils are not differentiated by the content of most elements, except for phosphorus concentrated in the surface organogenic horizons. By their chemical and physicochemical properties, soils of the cold mountain (goltsy) desert are similar to Entic Folic Podzols formed under dwarf-shrub vegetation in the mountain-tundra located downslope. The biological activity of petrozem soils is lower than or comparable to that in soils of dwarf-shrub tundra. It is established that the microbial activity increases and soil organic matter stabilizes when the vegetation becomes more patterned. Overall, microbial communities of petrozem soils are well adapted to extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Questions on sustainable and appropriate cropping systems for bioenergy sweet sorghum in the smallholder farming sector still exist. Therefore, a short-term experiment was carried out to study the influence of management on microbial biomass carbon (MBC), β-glucosidase, acid phosphatase, and urease activities in a sweet sorghum cropping system in South Africa. Tillage [no-till (NT) and conventional tillage (CT)], rotation [sorghum-vetch-sorghum (S-V-S) and sorghum-fallow-sorghum (S-F-S)] and residue retention [0%, 15% and 30%] were evaluated. Tillage× rotation× residue management interaction influenced (P < 0.05) MBC whilst crop rotation residue influenced (P < 0.05) β-glucosidase. Tillage affected β-glucosidase (P < 0.05), acid phosphatase (P < 0.001), and urease enzyme (P < 0.01) while crop rotation only influenced acid phosphatase (P < 0.01). Residue retention affected acid phosphatase (P < 0.001) and urease enzyme (P < 0.001). NT + S-V-S+30% interaction resulted in the highest MBC content compared to CT + S-F-S+0%. NT+30% enhanced β-glucosidase activity, S-V-S enhanced acid phosphatase compared to S-F-S. MBC and enzyme activities were positively correlated with each other. Tillage and residue management were the main factors influencing soil biological indicators under bioenergy sweet sorghum in South African marginal soils in the short-term. Soil biological indicators were higher under NT and 30% residue retention respectively. NT + S-V-S+30% was a better treatment combination to enhance soil quality under bioenergy sweet sorghum in South African marginal soils.

Climate change has an impact on agricultural production, including the greater persistence of plant pathogens in the environment. Therefore, the question arises as to how to effectively and safely protect plants by using chemicals, the number of which is decreasing each year. The aim of this study was to evaluate the fungistatic effect of 2 acetylthiophenethiosemicarbazone (2actpTS) and Cis-jasmonethiosemicarbazone (JTS) against Fusarium culmorum (Fc) on winter wheat seedlings. The influence of thiosemicarbazones (TSs) on the health status and phytotoxicity of seedlings and soil biological activity was investigated. Before TSs application (watering or spraying), soil was infected with F. culmorum (strain No. 37). The substance type and method of its application significantly influenced only the fresh weight of the seedlings. The varying phytotoxicity of the molecules depended primarily on their application method to the plants. The highest seedling phytotoxicity was recorded when compounds were applied during watering and the lowest when they were sprayed. The results showed that the application of substances 2actpTS and JTS, both in the form of watering and spraying, had a positive effect on plant health status, as expressed by the disease index (DI) value. The presence of the infectious agent and the type of chemical compound increased soil enzyme activity. The highest total number of bacteria was found in the soil that was infected with Fc and in soil samples where JTS was applied by watering and spraying. The highest utilization of amines, amides and amino acids by microorganisms was found in the samples where JTS was applied. The obtained results will be used to create intermediate products for the protection of cereals against Fusarium diseases, not only at the stage of germination and tillage of plants, but also at subsequent developmental stages.

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• Plant growth limiting properties were not consistently related to topography. • Loss of NO 3 − and S (0–30 cm) over time continued despite use of cool-season annuals. • Overall, SOM increased 6% (0–15 cm) with cool-season annuals and rotational grazing. • Stable total C and N (0–30 cm) over time indicated system equilibrium was attained. Over-seeding cool-season annual forages in pastures in the southeastern US provides increased grazing opportunities for livestock and reduces the amount of hay needed during winter. The constant presence of vegetation can benefit soil health, the biological aspect of which has only received cursory investigation to date. Since 2009, a commercial cattle grazing operation located in south Mississippi has been over-seeding a diverse mixture of oats (Avena sativa L.), triticale (X Triticosecale Wittmack), annual ryegrass (Lolium multiflorum Lam.), hairy vetch (Vicia villosa Roth), radish (Raphanus sativus L.), turnips (Brassica rapa L. subsp. rapa), red clover (Trifolium pratense L.), ball clover (Trifolium nigrescens Viv.), and crimson clover (Trifolium incarnatum L.) into pastures dominated by bahiagrass (Paspalum notatum Flüggé). Soil health properties were assessed across a heterogeneous landscape from soils collected immediately prior to seeding and following increased spring productivity of cool-season annuals from 2015 to 2017. Samples were collected across a topographic sequence to a depth of 15 and 30 cm. Three samples per site were collected from summit, backslope, and footslope locations. Soil chemical assessments included macronutrients, pH, soil organic matter (SOM), total carbon (TC), and total nitrogen (TN). Fatty acid methyl ester analysis and enzyme assays were used to determine soil microbial community structure and activity. While TC and TN did not change with time (20.5 and 2.4 g kg−1, respectively), SOM increased by 6% from 2015 to 2017. Nitrate-N decreased by 82% from 2015 to 2017. N-acetyl-β-glucosaminidase activity increased by 32%, while β-glucosidase remained constant. Total microbial abundance did not change with time; however, Gram positive bacteria and actinomycetes decreased by 51% and 43%, respectively, from fall to spring. Arbuscular mycorrhizal fungi increased from fall to spring by an average of 45%. This pasture management technique of over-seeding a diverse mix of winter annuals may have resulted in a steady state of TC and TN, while SOM increased and inorganic nitrogen decreased with time, and enhanced the total soil microbial community particularly fungi and their potential enzyme activity. Despite some biological indications of system stability, soil properties potentially limiting to plant growth were identified for some sites, but these limitations were not closely related to topographic position as expected. [ABSTRACT FROM AUTHOR]

• Multiple positive effects on biological control of pests from the native Australian plant Mentha satureioides. • Strong attraction of hymenopteran pollinators and native butterflies by M. satureioides and another native Lotus australis. • Soil biological activity was depressed by the exotic plant, buckwheat, compared with grassy control and all native plants. • Vegetation management can deliver multiple ecosystem services but plant identity is shown to be crucial. Habitat management can enhance the strength of ecosystem services but carries also the risk of leading to ecosystem disservices unless trophic links and ecosystem functions are well understood. In this study, intercropping with Australian native flowering plants was compared with the use of an exotic plant, buckwheat (Fagopyrum esculentum) and naturally occurring weedy grass vegetation for the provision of multiple ecosystem services in a cabbage agroecosystem. Among the native plants studied, Mentha satureioides had the most comprehensive positive effects on pest management. Compared with the grassy control, M. satureiodides significantly enhanced parasitism of the pest, Plutella xylostella (L.) (Lepidoptera: Plutellidae) larvae and reduced pest Brevicoryne brassicae densities and was comparable to F. esculentum. Flowers of M. satureiodides appeared attractive to adult Pieris rapae and the adjacent cabbage foliage held high densities of this pest's eggs but, reflecting high densities of parasitoids and predators (especially spiders), larval densities were not elevated compared to other treatments. Lotus australis also enhanced natural enemies, especially coccinellids and spiders, but this did not translate into the ecosystem service of pest suppression. Swainsona galegifolia harboured elevated numbers of spiders but the adjacent crop did not benefit from enhanced enemy densities or suppressed pests. For complementary ecosystem services, pollinator abundance was enhanced by the exotic plant F. esculentum and two natives (L. australis and M. satureioides). Honey bees (Apis mellifera) were highly attracted to F. esculentum , while native bees were attracted to the native plants. Native butterflies were monitored as a proxy for benefit to native invertebrate biodiversity and two native plants (L. australis and M. satureioides) were found to be attractive. Soil biological activity, a proxy for soil-associated ecosystem services, was lower in the F. esculentum treatment compared to all other treatments. These results show scope for farmers to take advantage of particular, and potentially multiple, ecosystem services by incorporating native flowering plants into farming systems but highlights the importance of plant selection and the risk of trade-offs among services. [ABSTRACT FROM AUTHOR]

The application of organic fertilizers (60 t/ha of dung) to gray forest soils increases the proportion of deeply humified humus substances within a humus, so the soils become more cultured. The organic-mineral fertilizer system (12 t of dung and 220 kg of NPK – nitrogen-phosphorus-potassium – per 1 ha of crop rotation area) and the organic fertilizer system (24 t/ha of dung) result in humus wide reproduction at the level of 1,32% and 1,35% comparing to the initial level (1,20%). The regular input of fresh organic fertilizers into soil caused the 1,5-times increase of intensity of biological processes (according to СО2 release) if compared to the soil without such an input. The intensity of CO2 release rose by 56% while applying organic-mineral fertilizers, by 28% with organic fertilizers, and by 14% with mineral fertilizers if compared to the control soil without applying fertilizers (118 mg of carbon-dioxide per 1 sq.m./h). The input of organic fertilizers in soil changed the concentration of microorganisms which decompose cellulose, and they prove to be rather good indicators of changes of soil agronomical properties. The cellulose-decomposing activity of soil nourished only with mineral fertilizers was 38,9%, that is a medium intensity. The cellulose-decomposing activity of soil amended only with fresh organic fertilizers rose to 80% that corresponded to a strong intensity. Fertilizing with both organic and mineral material stimulated the process of cellulose decomposing up to 82,4%. The intensity of a nitrification process reflects a potential soil biological activity. According to the research, the low nitrification intensity was observed in soil without fertilization (12,8 mg/kg), while the nitrification intensity rose to 14,0 mg/kg after mineral fertilization and to 17,4 mg/kg after organic fertilization. We revealed that the nitrification ability of soil tended to increase up to 21,9 mg/kg following the combined application of organic and mineral fertilizers, consequently coordinating with cellulose-decomposing activity changes of soil microbial cenosis under field conditions. [ABSTRACT FROM AUTHOR]

Purpose: Continuous cropping obstacles derived from long-term intensive cultivation has severely affected the healthy development of greenhouse vegetable industry in China. The alterations in soil microbial communities are commonly thought to be the important reasons behind continuous cropping obstacles. However, little attention is focused on soil functional microorganisms, such as soil ammonia oxidizers, which convert NH3 to NO2− in soils and play an important role in terrestrial ecosystem N cycling.Materials and methods: With the help of quantitative real-time PCR and high-throughput sequencing methods, this study investigated the effects of consecutive greenhouse vegetable cultivation on the abundances and community structures of ammonia-oxidizing archaea (AOA) and bacteria (AOB).Results and discussion: Continuous greenhouse production significantly affected soil physicochemical properties but slightly influenced on soil biochemical properties. Long-term greenhouse production significantly decreased soil potential nitrification rates. The abundances of AOA and AOB were insensitive to continuous greenhouse cultivation, whereas their community structures were significantly altered. A significant increase in average relative abundance of Nitrososphaerales Clade B4 in AOA community was observed after long-term greenhouse cultivation but just the opposite for Nitrososphaerales Clade Nitrososphaera. Increasing greenhouse cultivation years decreased the average relative abundance of Nitrosospira in AOB community, and their ecological niches were gradually occupied by Nitrosomonas; consequently, Nitrosomonas dominated AOB community under long-term greenhouse vegetable cultivation. Soil physicochemical properties, but not biological activity, were directly linked to the shifts of community structures of ammonia oxidizers. Moisture and total nitrogen significantly regulated AOA community structure, whereas organic matter and salinity mediated that of AOB.Conclusions: Our results demonstrated that consecutive greenhouse production obviously affected soil N turnover through altering community structures of nitrifiers, and soil functional microorganisms should be taken more attention when exploring the mechanisms for continuous cropping obstacles of greenhouse vegetable. The current study also highlights the fast adaptation of both AOA and AOB communities to complexly varied soil physicochemical environments. [ABSTRACT FROM AUTHOR]

Climate change and intensified land use simultaneously affect the magnitude and resilience of soil-derived ecosystem functions, such as nutrient cycling and decomposition. Thus far, the responses of soil organisms to interacting global change drivers remain poorly explored and our knowledge of below-ground phenology is particularly limited. Previous studies suggest that extensive land-use management has the potential to buffer detrimental climate change impacts, via biodiversity-mediated effects. According to the insurance hypothesis of biodiversity, a higher biodiversity of soil communities and thus an elevated response diversity to climate change would facilitate a more stable provisioning of ecosystem functions under environmental stress. Here we present results of a two-year study investigating, at fine temporal resolution, the effects of predicted climate change scenarios (altered precipitation patterns; passive warming) on three grassland types, differing in land-use intensity, soil biological activity, and in resilience. We show that future climate conditions consistently reduced soil biological activity, revealing an overall negative effect of predicted climate change. Furthermore, future climate caused earlier and significantly lower peaks of biological activity in the soil. Land-use intensity also significantly decreased soil biological activity, but contrary to general expectations, extensive land use did not alleviate the detrimental effects of simulated climate change. Instead, the greatest reduction in soil biological activity was observed in extensively-used grasslands, highlighting their potential vulnerability to predicted climate change. To assure high levels of biological activity in resilient agroecosystems, extensive land use needs to be complemented by other management approaches, such as the adoption of specific plant species compositions that secure ecosystem functioning in a changing world. [ABSTRACT FROM AUTHOR]

Abstract Sewage sludge (SS) has been used in agriculture on a large scale in Europe. In tropical climate conditions, due to rapid organic matter degradation, SS can provide toxic elements that can cause damage to the environment. We evaluated an area that received doses of SS for 10 years compared to mineral fertilization. The biogeochemical parameters (amylase, cellulase, invertase and dehydrogenase activity, carbon microbial biomass, basal respiration, metabolic quotient, soluble carbohydrates, total carbohydrates and glucose) and maize agronomic performance were evaluated. There was no increase of organic matter in the area due to the SS application. However, the application of SS for 10 consecutive years influenced the biogeochemical parameters evaluated in a similar way to the area that received mineral fertilizer. The SS proved efficient in completely replacing P fertilization and micronutrients. SS can also partially replace N fertilization without reducing maize productivity. Graphical abstract Unlabelled Image Highlights • Ten years of application of sewage sludge (SS) on tropical soil was evaluated. • Performance of maize cultivation and soil quality were the parameters used. • Ten years of application of SS did not increase soil organic matter. • The SS proved efficient in completely replacing P fertilization and micronutrientes. • SS and mineral fertilizer application was similar to biochemical parameters evaluated. [ABSTRACT FROM AUTHOR]

The vegetation concrete eco-restoration technology is a slope restoration technique used to strengthen slope stability and restore slope vegetation. The key issue in the entire technique is the composition of vegetation concrete suitable to the slope stability and re-vegetation. The objective of this study is to determine the appropriate cement content in vegetation concrete in the application of vegetation concrete eco-restoration technology. A series of systematically designed experiments were conducted on Cynodon dactylon and Medicago sativa with different cement content treatments to assess the effects of cement on the soil physico-chemical properties, enzyme activities and microbial biomass. The soil organic matter (SOM), soil total nitrogen (TN), enzyme activities and microbial biomass were significantly lower in high cement content treatments. A multi-index fuzzy comprehensive evaluation model was established to calculate the SBAI value, which can comprehensively evaluate how soil enzyme and microbial biomass characterized the quality change under different cement contents. The SBAI values of high cement content vegetation concrete were smaller than those of low cement content. Moreover, the SBAI value declined sharply when cement content reached 8%. And the SBAI values of unplanted sites were smaller than planted sites. The research found the quality of vegetation concrete reduced remarkably when cement content exceeded 8%. The 4-8% cement content appeared to be the appropriate range of cement content in vegetation concrete for the two studied species when plant growth and soil quality be taken into account. [ABSTRACT FROM AUTHOR]

Legume and Cereal Cropping in Zaï System with Different Organo-mineral Amendments - Productivity and Impact on Biological Properties of Degraded Bare Alfisol in North Sudanian Zone of Burkina Faso. Zaï is an agricultural practice that allows the cultivation of abandoned degraded soils. An experiment was conducted from 2006 to 2012 in Burkina Faso to assess the impact of this practice on the production of sorghum and cowpea, as well as on the biological properties of soils. The experiment was set up according to a factorial experimental design in Fischer blocks. The crops were grown in the trial , received different types of organic (manure, compost) and mineral (rock phosphate) input. The results showed that the intake of simple manure and compost significantly increased the yield of the two crops. The addition of phosphate (2 t.ha-1) to compost (3 t.ha-1) and to manure (3 t.ha-1) increased the yields of cowpea and sorghum respectively by 70 to 80% and 88 to 160% compared to sole compost and manure applications. The biological activity of the soil was not influenced by the type of crop but rather by organo-mineral intakes. The combination of rock phosphate to manure had a particularly positive effect on soil biological activity. The natural phosphate intake associated with organic matter therefore appears essential to maintain crop production and soil properties.