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Context: The rice-wheat (RW) system, spanning 13.5 million hectares in South Asia, is crucial for food security and livelihoods. However, intensive conventional tillage-based practices have harmed soil and environmental health, decreased productivity trends and increased greenhouse gas emissions. Objective: This study aims to develop resilient, climate-smart cropping systems within the RW system, focusing on soil and crop productivity, economic viability, and reduced greenhouse gas (GHG) emissions. Methods: Over eight years, the study evaluated diverse parameters compared to farmer practices (FP) in seven scenarios (Sc), including one representing FP (Sc1) and six based on conservation agriculture (CA) principles. The study assessed system crop productivity, economic returns, soil quality (organic carbon; OC, nitrogen; N, phosphorus; P, potassium; K contents, bulk density; BD, soil aggregation, infiltration rates, microbial counts, and earthworm density), and GHG emissions. Results: CA-based scenarios (Sc2 to Sc7) showed improved soil quality, lower bulk density, enhanced soil aggregation, and increased infiltration rates compared to Sc1. In the 0–15 cm layer, surface soil organic carbon (OC) and C stock were 63.7 % and 49.6 % higher, respectively, in CA-based scenarios. Additionally, available N, P and K contents in the surface layer increased by 10.2 %, 28.6 %, and 21.8 % under CA-based scenarios. Adoption of CA in intensified maize-based scenarios (Sc4 and Sc5) led to the increased system and economic yields, higher soil quality index (SQI), reduced GHG emissions and increased C stock compared to Sc1. Implications: The study highlights that Conservation Agriculture (CA) practices and diversified crop rotations can address issues like falling crop productivity, reduced economic returns, soil degradation, and increasing environmental impacts in northwestern India's traditional rice-wheat system. However, widespread adoption requires government policies, including C credit payments and guaranteed markets with supportive pricing.

AbstractThis study examines weed management in legume crops in Morocco. Faced with the challenges of climate change, financial profitability, and herbicide resistance, farmers are adopting a range of strategies, from plowing to herbicide use to agroecological practices. A survey of 244 farmers was conducted in different regions of Morocco. The results show that crop rotation is the most common weed management practice (81.15%), followed by herbicide use (59.43%) and manual weeding (35.25%). Major challenges include weed diversity (81.16%) and weed control budget constraints (84.84%). Farmers’ observations suggest that larger plots are associated with higher weed frequency, underlining the importance of adjusting herbicide application according to field size. In summary, Moroccan farmers are adopting an integrated approach, combining plowing, crop rotations, and herbicides for effective weed management, while facing complex challenges. It is essential to promote innovative and sustainable farming practices, guided by the results of this study, with an emphasis on developing weed-resistant legume varieties. In addition, raising farmers’ awareness of best practices, including the judicious use of herbicides, is crucial for sustainable agriculture in Morocco. [ABSTRACT FROM AUTHOR]

Residue incorporation is not a common practice in many production systems in areas with a Mediterranean climate. The aim of the research was to study the effect of residue incorporation levels of three cycles of two biannual rotations on corn yield and chemical properties of soil after six years. An experiment was conducted with two biannual rotations (canola-corn and bean-corn) and four residue incorporation levels (0%, 50%, 100%, and 200%) in a Chilean Andisol (Melanoxerand). Corn grain yield and residue production were evaluated during three cycles of crop rotation, and the soil's chemical properties were evaluated at the end of the evaluation round. The experimental design was a split plot, in which the main plot was the previous crop (two crops) and the split plot was the residue level (four levels). The results showed that the highest corn grain yield was obtained in the first evaluation season (p<0.05), when the average yield for both rotations was 10.1% higher than the average yield obtained in the third season. On the other hand, the average residue production of the first two seasons was 15.2% higher than that obtained in the third season (p<0.05). Chemical properties of the soil were affected by a rotation, with an increase in pH in the bean-corn rotation after bean cultivation, and an increase in both exchangeable Al and available S in the canola-corn and bean-corn rotations after canola. On the other hand, the use of increasing doses of residue enabled a consistent increase in the content of both organic matter and exchangeable K in the soil, and partially the available P in soil. The concentration of exchangeable Ca was increased with an increasing dose of residue only in the rotation with canola. Finally, this work allows us to conclude that continuous incorporation of the residues produced within the biannual rotations evaluated in this volcanic soil contributes to improvement of the soil's chemical properties, without affecting the corn crop yield. [ABSTRACT FROM AUTHOR]

Consumer demand for high quality organic produce in Canada has in recent years contributed to the development of a more sustainable organic agriculture system that increased productivity without decreasing soil fertility. The objective of this 4-yr field study was to determine if an organic system with diversified crop rotations under reduced tillage would produce high quality spring wheat (Triticum aestivum L.) grain and improve soil fertility. A simplified rotation (SR) consisting of a forage pea (Pisum sativum L.) green manure (GM)-spring wheat sequence and a diversified rotation (DR, forage pea GM-oilseed-pulse crop-spring wheat sequence) were compared under two tillage intensities (high tillage [HT] and low tillage [LT]). The oilseed alternated between mustard (Sinapis alba L.) and flax (Linum usitatissimum L.), and the pulse alternated between field pea and lentil (Lens culinaris L.). Generally, nutrient concentrations in wheat grain were mostly significantly higher under LT than HT and in the DR compared with the SR. In addition, tillage-rotation system influenced soil zinc, calcium, magnesium, and sodium concentrations. However, grain Cd concentration was higher in the LT treatment under the DR sequence relative to other treatments. Our results indicate that organically managed diversified crop rotations under reduced tillage can produce wheat grains with high nutritional value for humans and livestock but may not increase soil micronutrient concentrations.

A successful crop rotation choice is key to the profitability and sustainability of farm management and may simultaneously have an impact on soil organic carbon (SOC) content. In this study, we estimated how changes in crop rotations affected SOC balance in Finland between 2009 and 2018, using geospatial data and Bayesian modeling. The area designated for perennial-dominated and diverse cereal rotations increased over the study period. Perennial grassland rotation was found to have a positive impact on SOC balance, while rotations dominated by annual crops did not differ in their impacts on SOC content. At the national scale, changes in Finnish crop rotations resulted in an estimated annual mitigation of the loss of SOC content by 1336 Mg C year−1 in mineral soils and reduced the carbon dioxide emissions of organic soils by 10,475 Mg C year−1. The combined effect of these two contributions is 11,811 Mg C year−1, with an 80% probability interval of (−6600; 30,300) Mg C year−1. While the overall impact of changes in crop rotations on SOC is relatively small, a continued change to more diverse and perennial-dominated crop rotations may have other agronomic and environmental benefits, e.g. on resilience and biodiversity.

Background. For the first time in the abiotic conditions of the Lower Volga region on light chestnut soils, new methods of biologization of soil fertility preservation and specialized field crop rotations based on the replacement of pure steam with sideral steam with little–studied crops for green fertilizer – biennial yellow clover, oats and phacelia were developed and studied; the structure of sown areas includes cultures of various biological groups, including cereals, legumes, oilseeds, rowed and perennial legumes; in addition to siderates, organic fertilizers are used in the form of straw and crop –root residues of cultivated crops. The purpose of the work is the influence of pure and sideral steam on the yield of field crops Materials and methods. The study of the influence of sideral masses on the yield of grain crops in field crop rotations in the conditions of the Lower Volga region. Results. According to the conducted research, it has been established that biologized crop rotations are the first major stage in the transition to organic farming in the Volgograd region. The best option for the soils of the dry-steppe zone of chestnut subzones of light chestnut soils of the Lower Volga region is a four-field biologized field crop rotation and a five-field crop rotation with sideral steam (donnik). Conclusion. Data analysis showed that the best indicators of winter wheat yield were obtained for pure and sideral (sweet clover) pairs - 1.8 t/ha, chickpeas for the predecessor winter wheat in the five–field crop rotation - 0.87 t/ha and spring barley for the predecessor chickpeas – 1.48 t/ha.

The ongoing simplification of agricultural production systems has resulted in several negative consequences, ranging from losses in soil organic carbon and biodiversity to a high dependency on external inputs to maintain high yields. We identify how grassland leys in crop rotations may help to mitigate these effects, by conserving soil organic carbon and enhancing nutrient efficiency. In particular, grasslands containing legumes enhance these benefits by providing nitrogen, and displacement of mineral N fertilizer. In crop rotations, these grasslands may transfer some of the acquired nitrogen to arable follow‐on crops, thereby reducing the necessity for external inputs, while at the same time providing additional benefits, such as improvement of soil quality and reduction of weed pressure. However, there are still considerable knowledge gaps about how to optimize the community composition of grassland leys to best enhance the supply of these ecosystem services. Although the benefits of multi‐species grasslands for the grassland crop have been shown repeatedly and across a large gradient of environments, further research is required to determine the benefits for follow‐on crops, particularly across different environmental conditions. Here, we emphasize the importance of multi‐site research, such as in the research network LegacyNet. Finally, we present management techniques that are optimized for both ecosystem services and agronomic performance in mechanically cut and grazed systems. For the latter, we consider how the inclusion of bioactive plant species can enhance animal health and lower methane emissions in grazing ruminants. [ABSTRACT FROM AUTHOR]

The unreasonable use of fertilizers is a significant cause of cultivated soil cadmium (Cd) accumulation. Although there is research about the effect of fertilizers on soil cadmium (Cd) accumulation under different crops, soils, and cultivation durations locally and specifically, its relative and determinant factors are seldom comprehensively and comparatively researched and evaluated. We used meta-analysis to analyze the effects of fertilizers (mineral fertilizer N, P, K (NPK) with manure (NPKM), NPK with straw (NPKS), and the mineral fertilizer N (N), NK (NK)), crops, duration, climate, and soil texture on the Chinese soil total and available Cd change during 1987–2022. The results showed that the order of the increased soil total and available Cd change was NPKM (total: 62%–104%, available: 61%–143%) > NPKS (50%–86%, 48%–116%) > NPK (25%–50%, 35%–75%) > NK (5%–19%, 19%–33%) > N (2%–6%, 7%–31%). NPKM and NPKS significantly increased the total Cd under maize (104%, 86%) and available Cd under rice (136%, 116%). Cd changed the fastest with the NPKM cultivation duration for total Cd under maize (slope: 5.9) and available Cd under rice (6.6). The change of the soil total and available Cd had the higher value in the semiarid region, clay soils, lower pH, and long cultivations. The change of the soil total and available Cd were highest (398%, 375%) in the semiarid region for clay loam after 20–25 years of NPKM fertilization, when the pH decreased to the lowest (−1.9). According to the aggregated boosted tree analysis, the fertilizers and duration were the best explanatory variable (>53%) for the soil total and available Cd. In conclusion, the soil Cd could be mitigated through reducing the long–term manure, straw, and P fertilizer content with Cd, and field managements such as liming, wetting, and drying according to the crops, climate, and soil texture. [ABSTRACT FROM AUTHOR]

This extensive 10-year study conducted in Northern Kazakhstan investigates the intricate relationship between soil management techniques, crop rotations, and soil organic matter (SOM) content in Chernozem soils, an essential agricultural resource in the region. The experiments were established at the Karabalyk Agricultural Experimental Station, characterized by a arid continental climate. The study systematically examined the impact of two primary soil management techniques, conventional tillage (CT) and no-tillage (NT), in combination with various crop rotations. The crop rotations tested included grain-fallow rotations, fruit-exchange crop rotations, and an eight-field fruit-exchange crop rotation. The results provide valuable insights into the sustainable management of Chernozem soils in arid conditions, underscoring the role of crop rotation strategies in preserving SOM content. The findings reveal that among the crop rotations tested, the eight-field fruit-exchange crop rotation exhibited the most favorable outcomes for SOM preservation. This rotation helped maintain relatively stable SOM levels over the 10-year study period, contributing to soil health and fertility. In the context of the region's arid climate, the choice of soil management technique (CT or NT) had a limited impact on SOM content. The stability of SOM levels across diverse crop rotations and years highlights the dominant influence of crop management practices in this distinctive agricultural environment. This research serves as a valuable reference for tailored approaches to ensure soil health and organic matter preservation in the unique conditions of Northern Kazakhstan. It promotes the adoption of diversified crop rotations, with particular emphasis on the effectiveness of the eight-field fruit-exchange crop rotation, as a powerful strategy to mitigate organic matter loss, enhance soil quality, and optimize soil fertility in arid agricultural landscapes. The insights gained from this study are vital for sustainable land management in the region and underscore the importance of region-specific, holistic investigations to guide effective agricultural practices. The findings offer a solid foundation for the development of strategies that address soil health and safeguard the integrity of essential soil resources in these unique environments. The study conducted at the Karabalyk Agricultural Experimental Station in Northern Kazakhstan between 2011 and 2021 provides critical insights into the relationship between soil management techniques, crop rotations, and SOM content in Chernozem soils. The research suggests that diversified crop rotations, particularly the eight-field fruit-exchange crop rotation, represent a promising approach for mitigating organic matter loss and enhancing soil quality in arid regions.

This extensive 10-year study conducted in Northern Kazakhstan investigates the intricate relationship between soil management techniques, crop rotations, and soil organic matter (SOM) content in Chernozem soils, an essential agricultural resource in the region. The experiments were established at the Karabalyk Agricultural Experimental Station, characterized by a arid continental climate. The study systematically examined the impact of two primary soil management techniques, conventional tillage (CT) and no-tillage (NT), in combination with various crop rotations. The crop rotations tested included grain-fallow rotations, fruit-exchange crop rotations, and an eight-field fruit-exchange crop rotation. The results provide valuable insights into the sustainable management of Chernozem soils in arid conditions, underscoring the role of crop rotation strategies in preserving SOM content. The findings reveal that among the crop rotations tested, the eight-field fruit-exchange crop rotation exhibited the most favorable outcomes for SOM preservation. This rotation helped maintain relatively stable SOM levels over the 10-year study period, contributing to soil health and fertility. In the context of the region's arid climate, the choice of soil management technique (CT or NT) had a limited impact on SOM content. The stability of SOM levels across diverse crop rotations and years highlights the dominant influence of crop management practices in this distinctive agricultural environment. This research serves as a valuable reference for tailored approaches to ensure soil health and organic matter preservation in the unique conditions of Northern Kazakhstan. It promotes the adoption of diversified crop rotations, with particular emphasis on the effectiveness of the eight-field fruit-exchange crop rotation, as a powerful strategy to mitigate organic matter loss, enhance soil quality, and optimize soil fertility in arid agricultural landscapes. The insights gained from this study are vital for sustainable land management in the region and underscore the importance of region-specific, holistic investigations to guide effective agricultural practices. The findings offer a solid foundation for the development of strategies that address soil health and safeguard the integrity of essential soil resources in these unique environments. The study conducted at the Karabalyk Agricultural Experimental Station in Northern Kazakhstan between 2011 and 2021 provides critical insights into the relationship between soil management techniques, crop rotations, and SOM content in Chernozem soils. The research suggests that diversified crop rotations, particularly the eight-field fruit-exchange crop rotation, represent a promising approach for mitigating organic matter loss and enhancing soil quality in arid regions. [ABSTRACT FROM AUTHOR]

Integrated organic crop-livestock systems represent a sustainability model on which many environmental, economic and social expectations have been placed, especially in some areas with limited availability of natural resources. In recent years, among the fodder crops in rotation on organic livestock farms, conditions have been created for the emergence of soya (Glycine hispida, M.), also due to the coupled aid granted by the Common Agricultural Policy (CAP). A generalised spread of soybean, however, may generate unsustainable production patterns, especially in Mediterranean areas characterised by limited irrigation and weed management issues. With respect to the above, the research assessed the holistic sustainability of using field beans (Vicia faba, L.) in rotation for fodder purposes. To this end, a technical-economic and environmental analysis was carried out with economic balances and Life Cycle Assessment (LCA), through which a number of synthetic efficiency indices were developed. The results demonstrate the validity of the agronomic choice in achieving environmental efficiency, but also the importance of soil management and reducing the livestock load per unit area in order to simultaneously maintain economic and social efficiency levels.

Aim: Balanced crop nutrition is key to improve nutrient use efficiency and reduce environmental impact of farming systems. We developed and tested a dynamic model to predict the uptake of P and K in long-term experiments to better understand how changes in soil nutrient pools affect nutrient availability in crop rotations. Methods: Our RC-KP model includes labile and stable pools for P and K, with separate labile pools for placed P and organic fertilizers including farm yard manure (FYM). Pool sizes and crop-specific relative uptake rates determined potential uptake. Actual crop uptake from labile pools was based on concepts developed by Janssen et al. (Geoderma 46:299-318, 1990). The model was calibrated on three long-term experiments from Kenia (Siaya), Germany (Hanninghof) and the United Kingdom (Broadbalk) to estimate parameter values for crop-specific relative uptake rates and site-specific relative transfer rates. Results: The model described N, P and K uptake accurately with a Nash-Sutcliff modelling efficiency of 0.6–0.9 and root mean squared errors of 2.6–3.4 kg P ha−1 and 14–20 kg K ha−1. Excluding organic labile pools did not affect model accuracy in Broadbalk in contrast to Hanninghof where Mg deficiencies affected crop uptakes in treatments without Mg or FYM. Conclusions: This relatively simple model provides a novel approach to accurately estimate N, P and K uptake and explore short- and long-term effects of fertilizers in crop rotations. Interactions between limiting nutrients affecting actual nutrient uptake were captured well, providing new options to include N, P and K limitations in crop growth models. [ABSTRACT FROM AUTHOR]

The European Union's 'Green Deal' proposes an ambitious roadmap towards climate neutrality by 2050 and the adoption of a circular economy. Functional AgroBiodiversity (FAB) measures, which balance food production with minimised impacts on nature, are a promising way to achieve this on farmland. Here, we undertake a rapid evidence assessment to highlight Functional Agro-Biodiversity (FAB) management measures which help to realise biodiversity, climate neutrality, efficiency in use of natural resources and the circular economy. We report evidence on the effectiveness of 10 common FAB measures employed in Europe following a resurgence of interest and increased availability of data on their impact. The review found that the outcomes of implementing FAB measures were largely positive, with a number of mixed effects. There are evidence gaps, e.g., the impact of FAB measures on yield, the magnitude and timescale of impacts, the effect of landscape context. We signpost the most relevant and well-documented FAB measures, providing a reference for land managers and practitioners to select FAB measures to achieve specific ecological and agricultural outcomes. It is also important to note that a combination of measures implemented in a strategic way can enhance the output success. [ABSTRACT FROM AUTHOR]

The results of soil losses management studying due to wind and water soil erosion crops rotations proposed based on methodologies of NSC "Institute for Soil Science and Agrochemistry Research named after O.N. Sokolovsky". The main purpose of our research was to assess the soil losses under influence of wind and water erosion in crop rotation. The works were planned to determine how erosion types correspond to crops or having the same effect on a similar field parts in the crop rotation of Ukrainian Eastern Steppe part. It was also planned to compare soils losses in similar gradations (allowable, slight, moderate, high) with the following analysis of the differences in the manifestation dynamics under different agricultural crops (fallow, winter crops, barley, oat, corn for grain, corn for silage, millet, peas), and different parts of fields. It is proposed when determining the erosion risk of the territory, the areas of such soils must be protected by such crops with minimal losses from the destructive effects of wind erosion and surface runoff. It is possible to state the cumulative manifestation of erosion and deflation on the territory of the region, but it is impossible to separate the contours of eroded and deflated soils in detail, therefore, in erosion situations proposed to obtain separate influence of each erosion (wind and water) on already eroded or erosionally hazardous lands. [ABSTRACT FROM AUTHOR]

The unreasonable use of fertilizers is a significant cause of cultivated soil cadmium (Cd) accumulation. Although there is research about the effect of fertilizers on soil cadmium (Cd) accumulation under different crops, soils, and cultivation durations locally and specifically, its relative and determinant factors are seldom comprehensively and comparatively researched and evaluated. We used meta-analysis to analyze the effects of fertilizers (mineral fertilizer N, P, K (NPK) with manure (NPKM), NPK with straw (NPKS), and the mineral fertilizer N (N), NK (NK)), crops, duration, climate, and soil texture on the Chinese soil total and available Cd change during 1987–2022. The results showed that the order of the increased soil total and available Cd change was NPKM (total: 62%–104%, available: 61%–143%) > NPKS (50%–86%, 48%–116%) > NPK (25%–50%, 35%–75%) > NK (5%–19%, 19%–33%) > N (2%–6%, 7%–31%). NPKM and NPKS significantly increased the total Cd under maize (104%, 86%) and available Cd under rice (136%, 116%). Cd changed the fastest with the NPKM cultivation duration for total Cd under maize (slope: 5.9) and available Cd under rice (6.6). The change of the soil total and available Cd had the higher value in the semiarid region, clay soils, lower pH, and long cultivations. The change of the soil total and available Cd were highest (398%, 375%) in the semiarid region for clay loam after 20–25 years of NPKM fertilization, when the pH decreased to the lowest (−1.9). According to the aggregated boosted tree analysis, the fertilizers and duration were the best explanatory variable (>53%) for the soil total and available Cd. In conclusion, the soil Cd could be mitigated through reducing the long–term manure, straw, and P fertilizer content with Cd, and field managements such as liming, wetting, and drying according to the crops, climate, and soil texture.

ABSTRACTConservation agriculture (CA) is being promoted as an energy efficient and cost-effective farming system that conserves soil and water and improves crop yields. Adoption of this farming system can contribute to attainment of Sustainable Development Goal (SDG) 2: end hunger, achieve food security and improved nutrition, and promote sustainable agriculture. However, the adoption rate of this new farming technique by smallholder farmers in sub-Saharan Africa (SSA) is low. The trade-offs and synergies related to the three pillars that anchor CA have not, however, been investigated in the context of Botswana. Farmers are faced with trade-offs in the use of crop residue in CA as mulch with traditional use as feed for livestock. This paper reviews the components of CA with a view to contribute to the development of CA strategies for Botswana. We show that adoption of CA in SSA is challenged by lack of weed control measures, the lack of a market for grain legumes and competing uses of crop residue. The paper highlights the discrepancy between CA methods and current government subsidies, issues that may restrain the adoption of CA in Botswana. The paper concludes by making recommendations for research and policy development for sustainable CA practices in Botswana.

The use of acid soil‐tolerant annual legume pasture species and liming to raise soil pH can have legacy effects that improve subsequent wheat crop growth in acid soils. We established a two‐year experiment in a semi‐arid environment with and without historical lime application to investigate how acid soils (±lime) influence the legacy effects of annual legume pastures. We measured legume and cereal growth and yield, soil‐borne disease incidence, rhizosheath organic acid type and amount, legume biological nitrogen fixation (BNF) and soil moisture in Year 1, and soil microbial biomass carbon (MBC) and wheat yield and quality in Year 2. Minor differences in soil moisture and soil‐borne diseases occurred between cereals and legumes, and the poor BNF contribution of all pasture legumes improved in lime treatments. Pasture legumes produced more organic acids than cereals, which increased in limed treatments. Soil MBC in Year 2 was greater following legumes than cereals. Year 2 wheat grain yield increased following pasture legumes, more so in limed treatments. The contribution of organic acid exudation by annual legume pastures to microbial community legacy effects warrants further scrutiny in semi‐arid environments, particularly when acid soils limit typical rotational benefits. [ABSTRACT FROM AUTHOR]

According to published and archival data, the dynamics of soil plowing in Tula oblast in general and in its particular districts has been traced. It has been found that the active agricultural development in the southern part of the modern Tula oblast began no earlier than in the middle of the 17th century. According to the maps of different years, changes in the area of arable land in the Lokna River basin (Plavsk district of Tula oblast) from the end of the 18th century until the present time have been determined. The reliability of our data on the history of plowing of the territory is confirmed by the literature data. The composition of field crops and changes in farming systems during the period under review have been reconstructed, and a significant conservatism of these indicators has been revealed: the fallow three-field system dominated throughout the 19th century and the first half of the 20th century; the predominance of rye among winter crops and oats among spring crops remained until the 1970s. According to the WaTEM/SEDEM and using historical data on changes in the main factors of soil erosion as input parameters, the intensity and volumes of rainfall runoff for the selected stages of development of the Lokna River basin have been calculated. In order to compare the results with the literature data for the period of 1980–1993, the rates and volumes of snowmelt washout have been estimated. An assessment of the reliability of the reconstructed model parameters for remote historical epochs has been carried out. The analysis of historical changes in the factors and rates of erosion indicates that the maximum extent of plowed area and the maximum intensity of erosional processes in Lokna River took place in the last quarter of the 19th–early 20th centuries. The influence of particular geomorphic positions of arable land on the rates and volumes of soil erosion has been revealed. [ABSTRACT FROM AUTHOR]

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In research settings in the Eastern Gangetic Plain, Conservation Agriculture (CA) reduces operational costs, including cost for machinery, labour and fuel, while increasing yields, profit and soil organic carbon. However, the impact of the CA practices when adopted by smallholder farms on their crop productivity and farm profitability in this region is not well understood. In three locations in Rajshahi and Thakurgaon districts, Bangladesh, where previous on-farm CA research and demonstrations had been focused, we assessed the adoption and impacts of CA technologies on 135 farms compared to 270 non-adopters. While the CA technology adoption is still ongoing in the study areas, those farmers who practiced CA technology decreased human labour by up to 34%, seed use by 31%, fertilisers by 6%, pesticides by 32%, and total cost of production up to 10% while cultivating lentil, mustard, maize and wheat. The respective increases in crop yield and net profit were up to 28% and 43%, respectively. Propensity score matching (PSM) methods further confirmed that CA technology adoption had significant impacts by increasing crop yield, reducing variable costs, and increasing adopters' net income. Given the striking on-farm benefits of CA for smallholders in the EGP, programmes to expand the availability of minimum tillage planters, provide training to local service providers on CA methods, and the use of smart incentives should be evaluated to assist farmers to adopt CA seeding machinery and associated agronomic practices. [ABSTRACT FROM AUTHOR]

Conservation agriculture (CA) is being promoted as an energy efficient and cost-effective farming system that conserves soil and water and improves crop yields. Adoption of this farming system can contribute to attainment of Sustainable Development Goal (SDG) 2: end hunger, achieve food security and improved nutrition, and promote sustainable agriculture. However, the adoption rate of this new farming technique by smallholder farmers in sub-Saharan Africa (SSA) is low. The trade-offs and synergies related to the three pillars that anchor CA have not, however, been investigated in the context of Botswana. Farmers are faced with trade-offs in the use of crop residue in CA as mulch with traditional use as feed for livestock. This paper reviews the components of CA with a view to contribute to the development of CA strategies for Botswana. We show that adoption of CA in SSA is challenged by lack of weed control measures, the lack of a market for grain legumes and competing uses of crop residue. The paper highlights the discrepancy between CA methods and current government subsidies, issues that may restrain the adoption of CA in Botswana. The paper concludes by making recommendations for research and policy development for sustainable CA practices in Botswana. [ABSTRACT FROM AUTHOR]

Water erosion is a process that combines natural and anthropic factors, with effects on systemic productivity and the quality of natural resources. The objective of this work was to make estimates of potential (EP) and current (EA) losses of soil in production systems (SP) with different coverage and topographic characteristics, within the limits of the Ludueña stream basin (Santa Fe, Argentina), using the Universal Soil Loss Equation and the EROSION 6.0 program. For twelve SP, 10 years of rotations under no-tillage were modeled: continuous agriculture with a predominance of soybeans (AC), continuous intensive agriculture with a high proportion of grasses (ACi) and agricultural-livestock rotations with different proportions of pastures (AG 40:60 and AG 30:70). The estimated EP would affect systemic stability since it exceeds 18 tn.ha-1.year-1 in all cases. The EA was 18, 30 and 53% higher in AG 70:30, ACi and AC compared to AG 60:40, with maximum and minimum rates for the total simulations of 7.2 and 1.0 tn.ha-1.year-1. The characteristics of the relief showed that above the value of 0.131 of the LS factor (length and slope gradient), the AC would not be sustainable due to the high rates of EA and because these SP are associated with runoff routes that can facilitate transport of agrochemicals towards lower sectors. The information generated at the farm scale would allow progress in the study of the dynamics of the erosion process and its impact at the basin level. [ABSTRACT FROM AUTHOR]

Oomycetes are critically important in soil microbial communities, especially for agriculture, where they are responsible for major declines in yields. Unfortunately, oomycetes are vastly understudied compared to bacteria and fungi. As such, our understanding of how oomycete biodiversity and community structure vary through time in the soil remains poor. Soil history established by previous crops is one factor known to structure other soil microbes, but this has not been investigated for its influence on oomycetes. In this study, we established three different soil histories in field trials; the following year, these plots were planted with five different Brassicaceae crops. We hypothesized that the previously established soil histories would structure different oomycete communities, regardless of their current Brassicaceae crop host, in both the roots and rhizosphere. We used a nested internal transcribed spacer amplicon strategy incorporated with MiSeq metabarcoding, where the sequencing data was used to infer amplicon sequence variants of the oomycetes present in each sample. This allowed us to determine the impact of different soil histories on the structure and biodiversity of the oomycete root and rhizosphere communities from the five different Brassicaceae crops. We found that each soil history structured distinct oomycete rhizosphere communities, regardless of different Brassicaceae crop hosts, while soil chemistry structured the oomycete communities more during a dry year. Interestingly, soil history appeared specific to oomycetes but was less influential for bacterial communities previously identified from the same samples. These results advance our understanding of how different agricultural practices and inputs can alter edaphic factors to impact future oomycete communities. Examining how different soil histories endure and impact oomycete biodiversity will help clarify how these important communities may be assembled in agricultural soils. [ABSTRACT FROM AUTHOR]

Context: Crop rotations, within-field mixtures, and landscape mosaics including susceptible and resistant crops are three commonly adopted crop diversification strategies that can limit crop epidemics. Typically, the effects of crop diversification at these three scales have been studied separately, on single pathogen species, and with low environmental variability. Objectives: We aim to compare the disease-limitation effect of these three types of crop diversification on two highly damaging fungal pathogens of wheat Puccinia recondita (WLR) and Zymoseptoria tritici (STB) and under varying weather conditions (warmer or cooler climate for WLR, wetter or drier conditions for STB). Methods: We built a dynamic mathematical model of epidemics at the field scale (based on classical Susceptible-Exposed-Infectious-Removed epidemiological models) embedded in a spatially explicit landscape grid framework. We use it to simulate an agricultural landscape in which diversification translates into different proportions of wheat and resistant crops in the landscape. Results: In our simulations, for both pathogens and in all weather conditions, within-field crop mixtures had the greatest impact in limiting epidemics, crop rotations were second-best, while landscape mosaics were the least effective. We also found that the threshold above which further addition of resistant plants to crop mixtures would not cause further disease limitation to be dependent on weather conditions. The more favorable the weather is for pathogens the more resistant plants are required. Conclusions: Our findings imply that interactions between spatial scale of crop diversification, pathogen characteristics and weather conditions should be considered in order to maximize benefits from disease-regulation properties of diversified cropping systems under climate change. [ABSTRACT FROM AUTHOR]

The European Union’s ‘Green Deal’ proposes an ambitious roadmap towards climate neutrality by 2050 and the adoption of a circular economy. Functional AgroBiodiversity (FAB) measures, which balance food production with minimised impacts on nature, are a promising way to achieve this on farmland. Here, we undertake a rapid evidence assessment to highlight Functional Agro-Biodiversity (FAB) management measures which help to realise biodiversity, climate neutrality, efficiency in use of natural resources and the circular economy. We report evidence on the effectiveness of 10 common FAB measures employed in Europe following a resurgence of interest and increased availability of data on their impact. The review found that the outcomes of implementing FAB measures were largely positive, with a number of mixed effects. There are evidence gaps, e.g., the impact of FAB measures on yield, the magnitude and timescale of impacts, the effect of landscape context. We signpost the most relevant and well-documented FAB measures, providing a reference for land managers and practitioners to select FAB measures to achieve specific ecological and agricultural outcomes. It is also important to note that a combination of measures implemented in a strategic way can enhance the output success.

The Century Experiment at the Russell Ranch Sustainable Agriculture Facility at the University of California, Davis provides long-term agroecological data from row crop systems in California's Central Valley starting in 1993. The Century Experiment was initially designed to study the effects of a gradient of water and nitrogen availability on soil properties and crop performance in ten different cropping systems to measure tradeoffs and synergies between agricultural productivity and sustainability. Currently systems include 11 different cropping systems-consisting of four different crops and a cover crop mixture-and one native grass system. This paper describes the long-term core data from the Century Experiment from 1993-2014, including crop yields and biomass, crop elemental contents, aerial-photo-based Normalized Difference Vegetation Index data, soil properties, weather, chemical constituents in irrigation water, winter weed populations, and operational data including fertilizer and pesticide application amounts and dates, planting dates, planting quantity and crop variety, and harvest dates. This data set represents the only known long-term set of data characterizing food production and sustainability in irrigated and rainfed Mediterranean annual cropping systems. There are no copyright restrictions associated with the use of this dataset.

Climate change in the Mediterranean-like regions of South Africa has resulted in increased rainfall variability, a delayed start to the wet winter season, and increased occurrences of out-of-season summer rainfall events. These changes in bioclimatic conditions are predicted to become more pronounced and, therefore, could result in poor seedling establishment and false breaks from the soil seed bank, followed by seedling desiccation in annual medic and clover pastures. This study therefore aimed to quantify and compare the responses of three annual Medicago species and five annual Trifolium species to drought stress imposed at the seed germination, seedling establishment, and early seedling growth stages. Three separate controlled trials were conducted. Firstly, the seeds were germinated in seed germination chambers at constant temperatures ranging from 5 to 30 °C, in 5 °C increments, with five osmotic treatments within each temperature, and germination was recorded daily. For the second experiment, seeds were planted at 100, 70, 50, and 30% of the soil's moisture-holding capacity without subsequent watering, and emergence was recorded daily. For the third experiment, one-month-old seedlings were subjected to two water-limitation periods (15 or 30 days), and their subsequent morphological responses were measured. The results from these experiments indicated that the species differed significantly in their responses to drought, and the best-performing species often differed when drought was imposed at different development stages. Five species—M. polymorpha L., M. truncatula Gaertn., T. alexandrinum L., T. vesiculosum Savi., and T. subterraneum L. ssp. subterraneum—were able to tolerate incidences of drought better than other species and, thus, should be prioritized for further research into the variation in drought tolerance between cultivars within these species. [ABSTRACT FROM AUTHOR]

Agricultural challenge today is to maximize crop production reducing negative environmental impacts by efficiently use of resources and inputs. Objectives: i) to evaluate N2O emissions during a soybean-barley-maize rotation and their respective interperiods -chemical fallows (ChF) and cover crops (CC)-, and ii) to understand the relationships between N2O flow rates with soil mineral N content (Nmin), water-filled porous space (WFPS), and soil temperature (ST). N2O emissions were evaluated weekly under two management systems, ecological intensification (EI) and farmer current practices (FP). EI included higher N rates than FP, split N application, a cover crop (CC) after barley, among other management practices. Simultaneously to N2O emissions, Nmin, WFPS and ST were determined. The N2O fluxes were highest during crop periods (9-43, 6-61 and 4-104 µg N2O-N m-2 h-1, for soybean, barley and maize, respectively), intermediate during barley-maize interperiod (2-47 and 3-35 µg N2O-N m-2 h-1, for CC and ChF, respectively) and lowest during ChF of maize-soybean and soybean-barley interperiods (1-26 and 5-22 µg N2O-N m-2 h-1, respectively). Regression tree provided threshold splits for the effect of soil variables on emission rates: 7.4 mg N kg-1 for Nmin; 10.35 or 8.7°C for ST, depending on Nmin and WPFS values; 39.6 and 55.4 % for WPFS, both with high N. There were no significant differences in accumulated N2O emissions between management systems for the complete sequence (3050 and 3380 g N2O-N ha-1, for EI and FP, respectively). Yield-based N2O emissions for the complete sequence were lower for EI than for FP. EI decreased yield-scaled N2O emissions by 29% for soybean (p<0.05) and barley (ns) and by 30% for maize (p<0.05) compared with FP. In conclusion for the complete sequence, the EI system did not increase N2O emissions per unit area and reduced emissions per unit yield despite utilizing higher N rates and including a CC. [ABSTRACT FROM AUTHOR]

The research was carried out in the fields of the Lower Volga Research Institute. The work was completed in 2017-2020. The soil of the experimental site is light chestnut, heavy loamy, with a humus content of 1.74% in the arable layer. The average annual precipitation was 339.7 mm. The technology of cultivation of these crops was generally accepted for the research area. The placement of options (A) is sequential and options (B) are placed in blocks in three tiers. The main tillage in the experiment is soil-free, treated with a SibPME stand to a depth of 25-27 cm. Zoned varieties of agricultural crops are cultivated. Records and observations were carried out according to the recommendations. During the period July-August, the largest amount of precipitation fell in 2016 -- 119.0 mm; the smallest in 2017 -- 6.0 mm, in other years this indicator was in the range of 32.8-86.0 mm. On average, over the years of research, the largest accumulation of crop residues, straw and roots in a 4-pole crop rotation with black steam is 3.4 t/ha. The amount of nitrogen entering the soil with straw and crop residues was noted in an 8-month crop rotation of 49.8 kg/ha. The largest amount of biological nitrogen (according to Trepachev's method) was accumulated under alfalfa crops of 34.4 kg/ha. The analysis of soil samples for the content of humus over the years of research did not reveal significant changes. The best precursor for winter wheat is black steam. For perennial grasses, peas, the grain yield of winter wheat in some years is reduced by 4- 12 c/ha. The analysis of the correlation dependence of crop rotation productivity showed that the highest dependence with precipitation for May-June is t = + 0.50 for grain and feed units and slightly less for protein-t = +0.26-0.50. [ABSTRACT FROM AUTHOR]

The variations in temperature and rainfall patterns under climate change are threatening crop production systems, and optimizing fertilization practices is a prerequisite for sustainable cereal production. This two-year field study investigated the effects of eight treatments (T1: P60K60; T2: P60K60 + Nmin spring; T3: P60K60 + N40autumn + Nmin spring; T4: P60K60 + N60spring; T5: P60K60 + N100spring; T6: P60K60 + N40autumn + N60spring + Zn; T7: P60K60 + N60autumn + N80spring + Zn; and T8: P60K60 + N160spring + Zn) on the grain yield and quality of four divergent maize cultivars (NS-4023, NS-640, NS-6010 and NS-6030). The observations on climatic data showed substantial variations in monthly and cumulative rainfall only, which was 174 and 226 mm for 2011 and 2012, respectively, and much less than the historical cumulative rainfall of 339 mm. However, temperature during growth years showed little deviation from the historical data. The data showed that treatment and maize cultivar significantly influenced grain yield; however, grain yield remained lower in 2012 than in 2011 for each treatment and cultivar. Applying N as split doses in combination with Zn, resulted in higher grain yields than adding at once. However, the treatments and cultivars affected grain quality variables differently, including oil, thiol SH, phytate, inorganic P, soluble protein, starch, total phenol, protein, total sugars and tryptophan contents. Despite the pronounced difference in grain yields between 2011 and 2012 for each treatment and cultivar, grain quality did not always vary significantly between cultivars. Principal component analysis (PCA) revealed that the relationships between grain yield and grain quality varied significantly during 2011 and 2012. The changes in rainfall patterns at critical growth maize stages seemed to be a more important factor than temperature in regulating the response of maize cultivars in terms of grain yield and quality to various fertilization regimes in this study. [ABSTRACT FROM AUTHOR]

It is established that at the beginning of the 21st century due to significant exploitation of land resources of Ukraine, there was a violation of ecological balance in natural agroecosystems, intensified erosion and other degradation processes in soil, which now reached the highest level in the world. Due to the reduction in the use of organic fertilizers, the use of mineral fertilizers and pesticides has exceeded the permissible limits, which has led to pollution of soils, the environment and agricultural products with harmful chemicals. Currently, the use of physiological and genetic characteristics of crops belonging to different biological groups plays an important role in agrarian production in Ukraine. Along with the productive use of the genetic potential of crops, the use of modern innovative technologies, in particular the elements of biologization in organic farming, is of great importance. These include the systematic use of scientifically sound crop rotations, the use of optimal rates of organic and mineral fertilizers, green manure, post-harvest crops, biohumus, and minimize tillage. With increasing aridity of the climate, they adapt to new climatic conditions due to the accumulation and preservation of moisture, which is an effective measure in regulating soil water regime in the arid Southern Steppe of Ukraine. It was found that among the elements of biologization, the maximum use of natural mass of surface and root crop residues and by-products of crops -- cereal straw, tops and stalks of corn and sunflower, root crop buds and green manure -- is effective. Along with increasing the production of competitive agricultural products of better quality, their use ensures the efficient use of land resources, preservation and reproduction of soil fertility, improving the ecological state of the environment. It is determined that the use of plant residues actualizes the use of modern biodestructors, which are adapted to different soil and climatic conditions of Ukraine and technologies for cultivation crops. Of great importance in the production of corn for grain is the use of effective biodestructors of stubble Ecostern and Cellulad. Such studies are gaining relevance in the arid Southern Steppe of Ukraine, especially in climate change. [ABSTRACT FROM AUTHOR]

Soil compaction is a major physical constraint in cotton production. At present, no information is available on the effects of compaction on the root growth and root anatomy of cotton (Gossypium hirsutum L.). Therefore, we studied the effects of subsoiling (shallow (SSS) and deep (DSS)) and crop rotation (pigeon pea (Cajanus cajan) - cotton (PCR) and radish (Raphanus sativus) - cotton (RCR)) on the root growth of cotton in deep Vertisols during 2017-19. Subsoiling significantly increased the shoot and root length. The root-to-shoot ratio was maximum in DSS (33%), followed by PCR (29%) at the vegetative stage. Scanning electron microscopy analysis of the roots indicated a large number of pores and less contraction of xylem and phloem in the subsoiled and rotation treatments than in the control. Furthermore, the SEM-EDAX spectra indicated a greater abundance of major, secondary and micronutrients in subsoiling and crop rotations compared to the control treatment. [ABSTRACT FROM AUTHOR]

Crop rotation is known as an eco-friendlier approach, as provides diversification in crop management systems, modifies intensive pressure on the agricultural ecosystem, utilizes various soil horizons, and prevents the establishment of specific pests and weeds. We set out here a study on the farms that have been managed over 50 years of specific continuous crop management programs. The experimental treatments were in a different management system: monoculture of maize, winter wheat, and soybean, 2-year crop rotation (winter wheat–maize) with and without chemical fertilizer, and 3-year crop rotation (winter wheat–soybean–maize) with and without chemical fertilizer and manure. We took soil samples six times from 2014 to 2017 prior to sowing and after harvesting each year. Weed seeds were extracted from soils and identified and counted by species. We, upon the data of a long term experiment of crop rotation, could conclude that crop rotations with more crops in the sequence are significantly effective in maintaining weed populations, a low-input crop production could reach a constant low population below an important damaging density, and therefore will be a more sustainable crop production while chemical fertilizers would change the soil's chemical and structure and imbalance the plant population diversity and manures with high weed seed infestations have the potential to totally eradicate crop rotation effects, Therefore, clean manures or compost are highly recommended. [ABSTRACT FROM AUTHOR]

The rice-wheat (RW) system, spanning 13.5 million hectares in South Asia, is crucial for food security and livelihoods. However, intensive conventional tillage-based practices have harmed soil and environmental health, decreased productivity trends and increased greenhouse gas emissions. This study aims to develop resilient, climate-smart cropping systems within the RW system, focusing on soil and crop productivity, economic viability, and reduced greenhouse gas (GHG) emissions. Over eight years, the study evaluated diverse parameters compared to farmer practices (FP) in seven scenarios (Sc), including one representing FP (Sc1) and six based on conservation agriculture (CA) principles. The study assessed system crop productivity, economic returns, soil quality (organic carbon; OC, nitrogen; N, phosphorus; P, potassium; K contents, bulk density; BD, soil aggregation, infiltration rates, microbial counts, and earthworm density), and GHG emissions. CA-based scenarios (Sc2 to Sc7) showed improved soil quality, lower bulk density, enhanced soil aggregation, and increased infiltration rates compared to Sc1. In the 0–15 cm layer, surface soil organic carbon (OC) and C stock were 63.7 % and 49.6 % higher, respectively, in CA-based scenarios. Additionally, available N, P and K contents in the surface layer increased by 10.2 %, 28.6 %, and 21.8 % under CA-based scenarios. Adoption of CA in intensified maize-based scenarios (Sc4 and Sc5) led to the increased system and economic yields, higher soil quality index (SQI), reduced GHG emissions and increased C stock compared to Sc1. The study highlights that Conservation Agriculture (CA) practices and diversified crop rotations can address issues like falling crop productivity, reduced economic returns, soil degradation, and increasing environmental impacts in northwestern India's traditional rice-wheat system. However, widespread adoption requires government policies, including C credit payments and guaranteed markets with supportive pricing. [Display omitted] • Crop diversification improves physical, chemical and biological properties. • Crop residue retention influences nutrient balances and biological properties. • Reduces greenhouse gas emissions and yield-scaled global warming potential. • Productivity and profitability increase through crop diversification and management. • Crop diversification and residue retention improve soil quality index. [ABSTRACT FROM AUTHOR]

The results of modeling of potential soil losses due to surface soil runoff according to the current DSTU 7904: 2015 are considered. "Soil quality. Determination of potential threat of erosion under the influence of rains" on the slope of the field with contour-ameliorative organization of the territory (CAOT) on the lands of SE" DG Donetske" of NSC "Institute of Soil Science and Agrochemistry named after O.N. Sokolovsky" Bahmutsky district of Donetsk region, Ukraine. The main tasks of the work were: determination of potential soil losses on the slope of the fields to choose the more appropriate way of management in terms of using the working areas in the research system for black fallow, field crop rotation (excluding the impact of forest shelterbelts and taking into account the impact of shelterbelts), soil protective crop rotation. The use of working areas A and B under black fallow expectedly led to the excess of permissible soil losses in both areas, modeled according to the current DSTU 7904:2015 in Ukraine. Exceeding the allowable soil losses from erosion also occurred in section A under the conditions of its use for field crop rotation. Under the conditions of use of areas for soil protection crop rotation and in the conditions of functional compliance of forest shelterbelts, soil losses in both plots remain within the norm. In order to prevent the concentration of surface runoff from both working areas (A and B) in the lower part of the landfill, it is recommended to periodically apply the "rehabilitation" period with the organizing of soil protection crop rotation after black fallow. [ABSTRACT FROM AUTHOR]

This paper reviews the shifting fate of legumes in UK agriculture. Legumes were once a common part of crop rotations, providing food and feed, while enhancing soil fertility and enabling pest control. During the 20th century, UK arable management became predicated on minimally diverse crop rotations, dependent on artificial fertilisers and pesticides. Legumes were locked out of food and farming. Existing research has identified the drivers of this lock-in. Whilst this intensive model increased crop yields, there are growing concerns around its greenhouse gas emissions and impacts on soil health and biodiversity. In response, there is a resurgence of interest in legumes as a solution to these problems, as part of a wider shift towards agroecological management. This analysis draws on interviews with different actors in the UK agricultural sector to present a Multi-Level Perspective analysis of the drivers and characteristics of this transition - what we term agroecological break-out. It describes how macro-level economic changes (a growing market for plant-based proteins) and political transitions (a focus on public goods subsidisation) are combining with shifting agricultural attitudes (such as concerns around soil health, and the prioritisation of multi-annual profitability over annual yields) to increase the attractiveness of crop diversification and legume cropping. These changes open space for micro-level innovations by private, public, and civil society actors to disrupt the meso-level status quo of minimally diverse crop rotations. The conclusion maps the different forms and trajectories of this break-out and reflects on their implications for the future of food and farming in the UK. • Lock in of intensive agricultural management beginning to loosen. • Multi-level analysis is used to show signs of emergent 'agroecological breakout'. • Public goods policies and consumer preferences creating conditions for transition. • Growing industry interest in soil health and regenerative practices. • Great potential for use of legumes to diversify crop rotations in UK. [ABSTRACT FROM AUTHOR]

Background: Crop rotations with sugar beet (SB) vary in accompanying crops, affecting the organic matter input into the soil and thus the soil organic carbon (SOC) stocks. Furthermore, the impact of aboveground SB residues themselves on SOC stocks is unclear. Aims: The aims of this study were to analyze the effects of three SB rotations and different amounts of SB residues on SOC stock development. Methods: In a field experiment started in 2006, three different SB crop rotations [(1) SB–winter wheat (WW)–WW, (2) SB–WW–silage maize (SM), and (3) SB–WW–winter oilseed rape (WOR)–WW–WW–grain pea (GP)] were sampled for SOC stocks in 0–10, 10–20 and 20–30 cm soil depth in spring of 2018 and 2019. Further plots with an SB–WW–WW rotation received either no or the doubled amount of aboveground SB residues and were sampled as described above. Results: After four rotations, doubled SB residues led to significantly higher SOC stocks in 0–10 cm depth compared to the removal of SB residues. However, the effect was relatively low with 12% of the added residue‐C being recovered in the soil. Comparing different SB crop rotations, SOC stocks in 0–20 cm depth were significantly higher in the SB–WW–WW compared to the SB–WW–SM rotation, while the SB–WW–WOR–WW–WW–WW–GP rotation was intermediate. Differences in SOC stocks were likely due to the different amounts and possibly quality of crop residue C input. Conclusion: In total, the accompanying crops rather than the share of SB seem to be decisive for SOC development in SB rotations. [ABSTRACT FROM AUTHOR]

Understanding the influence of long-term crop management practices on the soil microbial community is critical for linking soil microbial flora with ecosystem processes such as those involved in soil carbon cycling. In this study, pyrosequencing and a functional gene array (GeoChip 4.0) were used to investigate the shifts in microbial composition and functional gene structure in a medium clay soil subjected to various cropping regimes. Pyrosequencing analysis showed that the community structure (β-diversity) for bacteria and fungi was significantly impacted among different cropping treatments. Functional gene array-based analysis revealed that crop rotation practices changed the structure and abundance of genes involved in C degradation. Significant correlations were observed between the activities of four enzymes involved in soil C degradation and the abundance of genes responsible for the production of respective enzymes, suggesting that a shift in the microbial community may influence soil C dynamics. We further integrated physical, chemical, and molecular techniques (qPCR) to assess relationships between soil C, microbial derived enzymes and soil bacterial community structure at the soil micro-environmental scale (e.g. within different aggregate-size fractions). We observed a dominance of different bacterial phyla within soil microenvironments which was correlated with the amount of C in the soil aggregates suggesting that each aggregate represents a different ecological niche for microbial colonization. Significant effects of aggregate size were found for the activity of enzymes involved in C degradation suggesting that aggregate size distribution influenced C availability. The influence of cropping regimes on microbial and soil C responses declined with decreasing size of soil aggregates and especially with silt and clay micro-aggregates. Our results suggest that long term crop management practices influence the structural and functional potential of soil microbial communities and the impact of crop rotations on soil C turnover varies between different sized soil aggregates. These findings provide a strong framework to determine the impact of management practices on soil C and soil health.