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The publication of the European Commission's Farm to Fork Strategy has sparked a heated debate between those who advocate the intensification of agriculture in the name of food security and those who recommend its de-intensification for environmental reasons. The design of quantified scenarios is a key approach to objectively evaluate the arguments of the two sides. To this end, we used the accounting methodology GRAFS (Generalized Representation of Agri-Food Systems) to describe the agri-food system of Europe divided into 127 geographical units of similar agricultural area, in terms of nitrogen (N) fluxes across cropland, grassland, livestock, and human consumption. This analysis reveals, in current European agriculture, a high level of territorial specialization, a strong dependence on long distance trade, and environmental N losses amounting to about 14 TgN/yr, i.e. nearly 70 % of the annual N input (including N synthetic fertilizers, symbiotic N fixation, oxidized N deposition and import of food and feed). Based on the analysis of the yield-fertilization relationship of cropping systems at the scale of their full rotation cycle, and on a simplified model of livestock ingestion, excretion and production, we advanced the GRAFS methodology for prospective scenario design. Three scenarios for the European agri-food system were explored for 2050: a business-as-usual (BAU) scenario, a scenario based on the measures considered by the EU Farm to Fork Strategy (F2F), and a fully agro-ecological scenario (AE). The results show that the F2F scenario reduces the dependence of Europe on imports of synthetic fertilizers and feed resources by 40 % as well as the environmental N losses by 30 %, but not to the level of its claimed ambitions as N lost to the environment still amounts to about 10 TgN/yr, i.e. 67 % of N inputs. Of the three scenarios studied, only in the AE scenario, involving the relocation of feed production, the generalization of organic crop rotations with N fixing legume crops, and a shift of agricultural production and food consumption toward less animal-based products, would Europe be able to dispense with N imports, still being able to export some cereals, meat, and milk products to the rest of the world, while halving today's reactive N emissions to the environment., Competing Interests: Declaration of competing interest The authors declare no competing interest., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

There is an urgent need for novel agronomic improvements capable of boosting crop yields while alleviating environmental impacts. One such approach is the use of optimized crop rotations. However, a set of measurements that can serve as guiding principles for the design of crop rotations is lacking. Crop rotations take advantage of niche complementarity, enabling the optimization of nutrient use and the reduction of pests and specialist pathogen loads. However, despite the recognized importance of plant-soil microbial interactions and feedbacks for crop yield and soil health, this is ignored in the selection and management of crops for rotation systems. We review the literature and propose criteria for the design of crop rotations focusing on the roles of soil biota and feedback on crop productivity and soil health. We consider that identifying specific key organisms or consortia capable of influencing plant productivity is more important as a predictor of soil health and crop productivity than assessing the overall soil microbial diversity per se. As such, we propose that setting up soil feedback studies and applying genetic sequencing tools towards the development of soil biotic community databases has a strong potential to enable the establishment of improved soil health indicators for optimized crop rotations., (© 2014 Society of Chemical Industry.)

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.

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 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 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.

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]

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.

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]

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]

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.

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.

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.

The aim of the article is to analyze optimization of cropping area of scientifically-based crop rotations in agriculture of Ukraine. Scientific solution of the set tasks required application of statistical data about cropping area in Ukraine, presentation of economic data of cultivated field crops in crop rotations. The authors of the article analyze long-continued research by the scientists of the Institute of Grain Crops of NAAS of Ukraine and suggest that yield capacity is much higher under scientifically-based crop rotations without application of fertilizers than under the variant of no crop rotation applied. The work studies optimization of the number of fields in a crop rotation. It is determined that efficiency of many-field crop rotation secures high level of agrarian production, and for enterprises with a small area of land use, it is the most reasonable to apply short crop rotation. [ABSTRACT FROM AUTHOR]

Crop diversification is a promising strategy to mitigate climate change through soil carbon sequestration while ensuring soil fertility maintenance and food security. Here, we assess the impact of different inter-cropping practices on soil organic carbon (SOC) and nitrogen (N) storage and stabilization under rainfed and irrigated semiarid conditions. Under rainfed conditions, an almond (Prunus dulcis Mill.) monocrop was compared with an almond inter-cropped with caper (Capparis spinosa) or with winter thyme (Thymus hyemalis). Under irrigated conditions, a mandarin (Citrus reticulata Blanco) monocrop was compared with a mandarin inter-cropped with an annual crop rotation (including Hordeum vulgare, Vicia sativa and Vicia faba) or with a triennial crop rotation (including Vicia faba, Portulaca oleracea and Vigna unguiculata L.). The SOC and N stocks, SOC mineralization rates, water-stable aggregates and associated OC and N contents were estimated at 0–10 and 10–30 cm depth in each monocrop and inter-cropping system after three years. Contrasting effects of inter-cropping on SOC and N stabilization were found in the rainfed and irrigated systems. The combination of inter-cropping and no tillage did not affect the SOC stocks or mineralization rates at any soil depth in the rainfed system, while it significantly increased the OC and N contents within the large macro-aggregates in the subsoil. Compared to the irrigated mandarin monocrop, the mandarins inter-cropped with the annual crop rotation showed a significant increase of 10% and 18% in the topsoil and subsoil N stocks, respectively, while the SOC mineralization rates were reduced by 30% at both soil depths. On the contrary, the topsoil SOC stock in the mandarins inter-cropped with the triennial crop rotation were reduced by 38% compared to the monocrop. Significant reductions ranging between 24% and 66% were also observed in the OC and N contents associated to the macro- and micro-aggregates in the topsoil and subsoil of both crop diversifications compared to the monocrop system. Our results highlight the potential of inter-cropping rainfed woody crops with perennials for boosting SOC and N storage and stabilization. In irrigated woody monocrops, inter-cropping with annual crop rotation schemes that include two or more leguminous and reducing tillage frequency operations seems to be more appropriate in terms of SOC and N stabilization. • Inter-cropping rainfed almond trees with perennials fostered subsoil OC and N stabilization. • Inter-cropping irrigated mandarin trees with annual crops hampered SOC and N stabilization at 0–30 cm. • Incorporating legumes when inter-cropping with annual crop rotations is pivotal to foster SOC and N storage. • Minimum tillage and crop residue retention is crucial to preserve and stabilize SOC and N. • Using cover crops as green manure during the first years is pivotal to restore semiarid agricultural soils. [ABSTRACT FROM AUTHOR]

Several studies indicate links between regional occurrence of well adapted weed species and crop rotations. Monocultures or very short crop rotation, which increased in the past decades are crucial for the establishment and dispersion of problematic weed species. In this study the impact of crop rotation on the occurrence of the species Amaranthus retroflexus (L.), Anchusa arvensis (L.) M. Bieb., Echinochloa crus-galli (L.), Galium aparine (L.), Geranium pusillum (L.), Sisymbrium officinale (L.), Solanum nigrum (L.), Stellaria media (L.) Vill., Viola arvensis Murray is investigated in four crop rotations with varying potential of crop health risks. Therefore, maize (M), oilseed rape (WR) and winter wheat [early sowing (WWF) and late sowing (WWS)] are cropped in four different rotations (M, WR – WWF, WR – M – WWS and WR – WWF – M – WWS) at two study sites in Germany since year 2008 (Rostock) and 2009 (Göttingen). At the start of the project selected weed species were sown into some plots in order to simulate an artificial similar weed pressure. In all plots weed species densities were counted before spraying in a standardized observation method. Analyses of four, respectively three years give evidences of crop specific effects regarding A. arvensis, E. crus-galli, G. pusillum, S. nigrum and S. media. Moreover, first effects of crop rotations on problematic weed species indicates that expanding crop rotations is a preventive tool to reduce weed densities.

The concept of sustainable intensification in crop production has become more and more important over the last years. Calls for an efficient production demand an increase in yield without extending the agricultural area or increasing the amount of agricultural inputs. Thus, our study aimed to identify which variables influence the efficiency in crop cultivation in Central Europe and how we can explain the variances between fields. The data base for the present study was a survey among sugar beet farmers in all parts of Germany in the years 2010–2014. In order to structure the fields, variables representing environment, management and farm characteristics were extracted. The performed analysis according to components (principal component analysis) did not result in a nationwide structure of the data. Thus, fields were grouped according to similar preconditions such as regions and crop rotations. Sugar yield ranged from 12.5 t ha −1 in 2010 to 15.4 t ha −1 in 2014 on nationwide average. The median value for N fertilization over all fields and years was 137.4 kg ha −1 , the median treatment index (TI) reached 3.7, the median field evaluation index (Ackerzahl) was 70 and the median field size 8 ha. We found that over 50% of the variance among the data was explained by environment, management and farm characteristics. The comparison of fields on a regional basis was more sensible than on a nationwide basis as the variance of farms and fields was too broad for a useful clustering. It was concluded that the adaption of the farmer’s management to regional specific conditions is an opportunity to reduce yield gaps and to increase efficiency in terms of a sustainable intensification in sugar beet production. [ABSTRACT FROM AUTHOR]

There is a great demand for high-protein materials for livestock feed in Europe and European agriculture has a deficit of about 70% high-protein materials of which 87% is met by imported soybean and soy meal. This reflects the fact that grain legumes are currently under represented in European agriculture and produced on only 1.5% of the arable land in Europe compared with 14.5% on a worldwide basis. Several grain legumes have the potential to replace at least some of the soya currently used in the diets of monogastric animals, ruminants, and fish. There are also opportunities for greater use of legumes in new foods. Here we review the contribution of ecosystem services by grain legumes in European agriculture starting with provisioning services in terms of food and feed and moving on to the contribution they make to both regulating and supporting services which are in part due to the diversity which these crops bring to cropping systems. We explore the need to understand grain legume production on the time scale of a rotation rather than a cropping season in order to value and manage the agronomic challenges of weed, pests, and diseases alongside the maintenance or improvement of soil structure, soil organic matter, and nutrient cycling. A review of policy interventions to support grain legumes reveals that until very recently these have failed to make a difference in Europe. We contrast the European picture with the interventions that have allowed the development of grain legume production in both Canada and Australia. Whether farmers choose to grow more legumes will depend on market opportunities, the development of supply chains, and policy support as well as technical improvements of grain legume production such as breeding of new varieties and management development to improve yield stability. However, to really increase the production of grain legumes in Europe, the issues are far more wide reaching than agronomy or subsidy and require a fundamental rethinking of value chains to move grain legumes from being niche products to mainstream commodities. [ABSTRACT FROM AUTHOR]

The objectives of this research were to determine the farmers knowledge level in Sinjar District / Nineveh Governorate in the fields of crop rotations, and to determine farmers knowledge level in each field and item, also to find out the differences of farmers knowledge according to some factors, and to determine the relationship between the degree of knowledge and a set of independent factors. The research sample included 72 respondents. The data were collected through an interview. Special questionnaire has been developed to estimate farmers knowledge level by using test method after testing the validity and reliability of the questionnaire. Percentage weight, arithmetic mean, analysis of variance and multiple step-wise regression analysis were used in analyzing the data. It was found that 52.778% of the respondents were of medium knowledge level in using crop rotations. The highest knowledge level of respondents were in the field of maintaining soil fertility. Also there were significant differences in the degree of farmers knowledge according to: age, education level, type of land tenure number of years using crop rotations, desire for renewal and previous training. While there were no significant differences according to: social statue and sources of information. Also it was found that the factor number of years using crop rotations explained 29.542% of the variation degree of farmers knowledge level.

Agricultural biodiversity and related agro-ecological measures could play a crucial role in the agro-ecosystems adaptation to climate changes, thus sustaining crop production. The objective of this study was to assess the suitability (and the best combination) of agro-ecological techniques as potential resilience strategies in organic horticultural systems in a Mediterranean environment. A long-term experimental device called MITIORG (Long-term climatic change adaptation in organic farming: synergistic combination of hydraulic arrangement, crop rotations, agro-ecological service crops and agronomic techniques) is set-up at Metaponto (MT), testing the following agro-ecological measures as well as organic and conservation farming best practices: i) hydraulic arrangement by a kind of ridge-furrow system; ii) cash crop rotations; iii) agro-ecological service crops (ASC) introduction; iv) ASC termination techniques (green manure vs roller crimper); and v) organic fertilisation. The research here reported was carried out during the 2014-2015 season in the MITIORG device, on a rotation of cauliflower (Brassica oleracea L.) and tomato (Solanum lycopersicum L.) crops. A detailed description of the scientific cognitive process that led to setup of the device, its components explanation, as well as preliminary yield results are reported. The outcomes suggest that organic vegetable cropping systems, designed following agro-ecological principles, are able to sustain yield of cash crops in rotation, in spite of changes in temperature and rainfall of the study site. Experimental data available in the next years will allow a deeper integrated analysis of the manifold effects of agro-ecological measures on horticultural systems.

Apresentam-se os resultados de um ensaio de rotações que decorreu durante dez anos em Vila Real (Trás-os-Montes). O ensaio incluiu a rotação tradicional das condições de sequeiro de Trás-os-Montes, cereal-alqueive (TA), e rotações alternativas susceptíveis de serem adoptadas nestas condições, cereal-leguminosa (TL), cereal-consociação forrageira (TC) e cereal-prado de sequeiro (TP). Os cereais das rotações foram o trigo e, posteriormente, o triticale. Determinaram-se e analisaram-se as produções de grão e palha, os teores de nutrientes do grão e da palha e acompanharam-se os parâmetros do solo, pH, matéria orgânica e os teores de P2 O 5, K2 O e bases de troca. Destacam-se alguns resultados importantes, tais como: as produções de grão de cereal das rotações não mostrarem diferenças significativas entre si; a produção de palha da rotação TL ser superior às das restantes; o trigo cultivado após prado de sequeiro não dispensar a adubação azotada; as rotações conduzirem a modificações dos teores de matéria orgânica, cálcio de troca ou do valor do pH do solo, factores a que se deve atender, caso a rotação se prolongue por muitos anos.The results of a field trial of crop rotations conducted over a period of ten years in Vila Real (Northeast Portugal) are presented. The rotations tested were cereal-cultivated fallow (TA), traditional in rain-fed conditions of the region, and alternative rotations that could be adopted in these conditions: cereal-grain legume crop (TL), cereal-forage mixture (TC) and cereal-rain-fed pasture (TP). The cereals were wheat and, later, triticale. Grain, straw and aerial biomass yields were evaluated together with concentrations of nutrients. The soil parameters studied were pH, organic matter and P 2 O 5, K2O and exchange cations. Wheat straw yield of TL rotation was higher than that of the others. Wheat from TP rotation still requires nitrogen fertilization. The soils of the different rotations registered changes of organic matter, Ca, Mg and pH values, which should be taken into account if these rotations are practised over several years.

This study was conducted at Sids Experimental Research Station, Beni Suief Governorate, starting from year 2000 to study the effect of rotation dura-tion (every year, 2- year rotation and 3- year rota-tion) and nitrogen fertilizer rates; 45, 60 and 75 kg N/ fed on growth, yield components and yield of cotton, as well as associated weeds. A split plot design was used with four replicates. The data indicated that crop rotation had significant effect on plant height, number of fruiting branches/ plant, number of open bolls, seed cotton yield/ plant and seed cotton yield/ fed. Seed cotton yield/ fed was increased by 10.99 and 23.62 % when 2-year and 3-year rotations were applied, compared to 1-year rotation (average of both seasons). In-creasing N- fertilization up to 60 kg N/ fed caused significant increases in all studied traits. The best estimate of yield (Y) plotted against N rate (X) for annually rotated cotton was the linear equation of Y =2.44 + 0.074x (R2 =0.81). Two years rotation showed a quadratic association with increasing the N rate, R2 = 0.86 and 0.88, respectively. The high-est values of total fresh weeds were 2.85 and 2.60 kg/ m2 (broad and grassy weeds) when 1-year ro-tation was applied, while the lowest values were 1.50 and 1.35 kg/ m2 when 3-year rotation was applied in the first and second season, respective-ly.

Purpose: This study aims to compare crop rotation systems used in organic farming (organic rotation systems) with those of both conventional farming (conventional rotation systems) and continuous rice cropping systems. Life cycle assessment (LCA) is performed based on land- and product-based indicators. Methods: Seven crop rotation systems for rice, barley, and soybeans and continuous rice production systems were evaluated in this study. These systems are practiced by farmers in the study region and were constructed using production records, statistics, and guidelines. Comparisons were then made between organic and conventional crop rotation systems and between these crop rotation systems and a continuous rice production system. We used land-oriented expression to analyze tradeoffs between physical and monetary productivity and the environmental impact per area unit and product-oriented expression to analyze efficiency as measured by the environmental impact per product unit. Results and discussion: Results are summarized as follows: (1) The product-oriented expression, which is equivalent to conducting product LCA, revealed that organic conversion tended to be efficient, irrespective of using physical productivity (the functional unit of product mass measured as averaged annual energy yield) or using monetary productivity (the functional unit of product mass measured as averaged annual income). (2) However, the land-oriented expression revealed that there were tradeoffs between physical productivity and environmental impacts, although these tradeoffs were converted to win-win relationships if monetary productivity was used instead of physical productivity, and (3) the alteration of a continuous rice production system into crop rotations tended to be efficient and enables a win-win relationship. Conclusions: Organic rotation systems have the potential of being recommended as sustainable agricultural practices in comparison with conventional rotation systems and continuous (organic and conventional) rice production systems. However, it was not clarified which productivity concepts should be used as evaluation criteria. It is considered that further studies using mechanistic modeling of crop rotations are required to improve LCA practices. [ABSTRACT FROM AUTHOR]

Abstract: Stable isotopic measurements (δ 15N and δ 18O), combined with hydrochemical assessment, were used to elucidate the chemical quality of groundwater and the sources of nitrate (NO3 −) in the groundwater in an agricultural region at Huzhou City, China. Paddy rice (Zhejing 41) and vegetables (Chinese cabbage) are the typical crops grown in the study area. The chemical properties of groundwater in the study area were controlled using natural geochemical processes and anthropogenic activities. The results show that SO4 2− and NH4 + were the major contaminants. Surficial conditions influenced the shallow groundwater. However, no relationship between the ion concentration in groundwater and well depth was found. The combined use of isotopes was useful for identifying NO3 − sources. The isotopic values for δ 15N and δ 18O ranged from −0.8‰ to 20.8‰ and from −2.0‰ to 18.8‰, respectively. The isotopic data were definitive and revealed that N-fertilizer, soil organic matter, and manure dominated the sources of NO3 − in the study area. The δ 15N and δ 18O data for NO3 − indicated a significant degree of nitrification and a lesser extent of denitrification in the agricultural area. Spatial variations in δ 15N for NO3 − showed that NO3 − concentration and δ 15N values in the upper groundwater (<200cm) were higher than the values in the lower groundwater (>200cm). [Copyright &y& Elsevier]

Sustainable and productive agroecosystems must be developed that will meet today's needs for food and other products, as well as preserving the vital natural resource base that will allow future generations to meet their needs. To increase production efficiency, to improve farming strategies based on local resources, and to design systems that are resilient in the face of changing climate require thorough understanding of the ecology of agricultural systems. Organic and sustainable farmers have developed many production practices and integrated crop/animal systems that are finding application in more conventional farming enterprises. While they do seek greater resource use efficiency and substitution of more environmentally benign inputs to replace chemicals used in conventional farming, sustainable farmers increasingly depend on thoughtful redesign of production systems to provide internal management of soil fertility and pests, careful use of contemporary energy and rainfall, and reliance on internal resources rather than imported inputs. Evaluation of systems based on productivity, sustained economic return, viable environmental indicators, and equitable social consequences of agricultural production are central to future sustainable farming and food systems. [ABSTRACT FROM AUTHOR]

Conservation agriculture can provide a low-cost competitive option to mitigate global warming with reduction or elimination of soil tillage and increase soil organic carbon (SOC). Most studies have evaluated the impact of zero till (ZT) only on surface soil layers (down to 30 cm), and few studies have been performed on the potential for C accumulation in deeper layers (0–100 cm) of tropical and subtropical soils. In order to determine whether the change from conventional tillage (CT) to ZT has induced a net gain in SOC, three long-term experiments (15–26 years) on free-draining Ferralsols in the subtropical region of South Brazil were sampled and the SOC stocks to 30 and 100 cm calculated on an equivalent soil mass basis. In rotations containing intercropped or cover-crop legumes, there were significant accumulations of SOC in ZT soils varying from 5 to 8 Mg ha−1 in comparison with CT management, equivalent to annual soil C accumulation rates of between 0.04 and 0.88 Mg ha−1. However, the potential for soil C accumulation was considerably increased (varying from 0.48 to 1.53 Mg ha−1 yr−1) when considering the soil profile down to 100 cm depth. On average the estimate of soil C accumulation to 100 cm depth was 59% greater than that for soil C accumulated to 30 cm. These findings suggest that increasing sampling depth from 30 cm (as presently recommended by the IPCC) to 100 cm, may increase substantially the estimates of potential CO2 mitigation induced by the change from CT to ZT on the free-draining Ferralsols of the tropics and subtropics. It was evident that that legumes which contributed a net input of biologically fixed N played an important role in promoting soil C accumulation in these soils under ZT, perhaps due to a slow-release of N from decaying surface residues/roots which favored maize root growth. [ABSTRACT FROM AUTHOR]

This 6-year experimental study measured the response of bird populations and abundance to combinations of mixed cropping and low pesticide regimes associated with a commercial crop rotation. The results show a rapid and sustained population increase among a wide range of bird species, in contrast to local regional trends for the same species. Seventy percent of the increase occurred within the first 3 years of the experiment, with species of high conservation concern, and those monitored as environmental indicators on lowland farmland in the UK, increasing on average, by 30% and 20% respectively (reaching respective peaks of 44% and 33% after 4 years). For some individual species, the increase was higher still, i.e., 300% (1–4 pairs) for grey partridge (Perdix perdix) and 46% (13–19 pairs) for skylarks (Alauda arvensis) in peak years. The results demonstrate that bird species typical of lowland arable farmland in the UK are responsive to suitable farm-scale changes in habitat and food provision (roughly, manipulation within less than 1-km2). They show that the carrying capacity of modern, commercially viable, arable farmland can be increased significantly for birds, in this case, mainly by using crops mosaics to create habitats alongside the appropriate use of herbicides on non-cropped habitats. [Copyright &y& Elsevier]

Diverse cropping systems can have significant impacts on nutrient losses through tile drain systems and to surface water bodies (rivers and streams). Increased transport of nitrogen to water bodies can reduce dissolved oxygen and enrich the supply of nutrients, resulting in hypoxic zones. With the objective of reducing the transport of nutrients from agricultural watersheds, long term studies (1990 to 1998) were conducted in Iowa to investigate the impact of tillage, crop rotation, and N-management practices on NO3-N leaching losses to tile drain water. Results of these studies indicated that continuous corn production systems required higher input of nitrogen fertilizers and resulted in significantly higher NO3-N leaching losses compared to rotated corn in plots either fertilized with manure or urea ammonium nitrate. Also, rotated corn gave higher corn yields, 8 megagrams per hectare (Mg/ha) versus 6 Mg/ha, than continuous corn. The higher N application rates resulted in increased NO3-N concentrations in tile water. A strip cropping system with alfalfa lowered NO3-N concentrations in tile water to less than 10 mg/I. These studies indicated that better land use practices can reduce NO3-N leaching losses to surface and ground water systems and will help in mitigating environmental concerns of the production agriculture. [ABSTRACT FROM AUTHOR]

Abstract: Nitrous oxide (N2O) emissions from agriculture are currently estimated from N inputs using emission factors, and little is known about the importance of regional or management-related differences. This paper summarizes the results of a study in which N2O emission rates were recorded on 15–26 occasions during a 12-month period in organic and conventional dairy crop rotations in five European countries (Austria, Denmark, Finland, Italy, UK). A common methodology based on static chambers was used for N2O flux measurements, and N2O data were compiled together with information about N inputs (from fertilizers, N2 fixation, atmospheric deposition and excretal returns), crop rotations and soil properties. Organic rotations received only manure as N fertilizer, while manure accounted for 0–100% of fertilizer N in conventional rotations. A linear regression model was used to examine effects of location, system and crop category on N2O emissions, while a second model examined effects of soil properties. Nitrous oxide emissions were higher from conventional than from organic crop rotations except in Austria and, according to the statistical analysis, the differences between locations and crop categories were significant. Ammonium was significantly related to N2O emissions, although this effect was dominated by observations from a grazing system. Despite the limited number of samplings, annual emissions were estimated by interpolation. Across the two systems and five locations there was a significant relationship between total N inputs and N2O emissions at the crop rotation level which indicated that annually 1.6±0.2% (mean±standard error) of total N inputs were lost as N2O, while there was a background emission of 1.4±0.3kgN2O-Nha−1 year−1. Although this measurement program emphasized system effects at the expense of high temporal resolution, the results indicate that N input is a significant determinant for N2O emissions from agricultural soils. [Copyright &y& Elsevier]

Abstract: Soil management practices such as crop rotations and crop production inputs can affect soil microbial communities. Carbon substrate utilization patterns have been used to distinguish microbial community functional activity in different ecosystems. Microbial community functional activity from a long-term crop rotation experiment (HRE) and from Pennsylvania farms was evaluated by analysis of microbial community-level physiological profiles (CLPP) based on Gram-negative Biolog® plate reactions. Principal component analysis (PCA) and cluster analyses of substrate reactions were analyzed after 72h of incubation. In the HRE, treatments with manure and crop rotations formed a different cluster than treatments with no manure and continuous corn. Farms with routine organic amendments formed a different cluster than farms with few or no organic additions. Whole plate metrics—mean plate intensity (MPI), number of C substrate reactions—were particularly effective as indicators of soil management impacts on microbial community activity. Substrate utilization diversity was different in treatments with manure additions and crop rotations treatments of HRE, but not for farms with different management. Although not without limitation, microbial community-level physiological profiling can be used as a tool to explore the impacts of different soil management on the functional activity of soil microbial communities. [Copyright &y& Elsevier]

Estimates of soil N mineralization capacity and the factors that control the rates are necessary for optimal N management. Long-term field experiments can be used to measure how different management options affect the amount and quality of soil organic matter (SOM) – the substrate for N mineralization. Net N mineralization was estimated in a pot experiment as N uptake by ryegrass (Lolium perenne) grown in pots with soils from 30 Swedish long-term field fertility experimental treatments (16–40 years). The long-term management effects of cereal and ley rotations, crop residue removal and return and inorganic N application on ryegrass N uptake were investigated and related to soil organic carbon (SOC) content. Total plant N uptake during three months varied between 9 and 27 mg N kg -1 (23–67 kg N ha -1 ) and increased with SOC concentration and previous application levels of inorganic N. Soil from crop rotations with ley mineralized about 50% more N than soil from crop rotations with only cereals. Plant N uptake and SOC were not significantly affected by crop residue return. [ABSTRACT FROM AUTHOR]

Rainfed crop yields in central Spain are low because precipitation is limited and highly variable. Further, farmers must minimise production costs to offset the continuous decline in price of the commodities produced. The objective of this 16-year work was to assess the economic feasibility of rainfed reduced (CP) and no-tillage (NT) systems compared to conventional-tillage (MP) for a winter wheat (Triticum aestivum L.)–vetch (Vicia sativa L.) rotation (WV) and a winter barley (Hordeum vulgare L.) monoculture (BM) system on a loam soil (Vertic Luvisol). The economic analyses compared gross margins in each rotation and tillage system and assessed the economic performance of a standard rainfed farm enterprise in central Spain based on 2001 input costs and product prices. Although statistically similar, average gross margin for WV was 16% higher than for the BM rotation. Tillage method had no influence on gross margins when averaged across years and rotations; however, gross margins tended to be higher for NT and CP than for MP. Significant differences were observed for the tillage method by crop rotation interaction. The highest gross margin was earned with NT in WV, followed by CP and MP in the same rotation. The lowest gross margins were earned with NT and MP in the BM rotation; whereas, gross margin for CP in BM did not differ from those earned with MP and CP in WV. On an annual basis, gross margins were significantly higher for WV than for BM in 5 of 16 years, similar in 9 years, and lower in 2 years. The breakeven size of farm enterprise was 103, 93 and 105 ha for MP, CP and NT, respectively. The tillage system with the lowest profitability threshold was CP and that with the highest was NT. MP and NT had lower variable costs associated with machinery operation, but NT also had higher herbicide costs. In relation to total costs, machinery costs accounted for 19% in MP and for 16% in NT, while herbicide costs increased from 4.9% in MP to 8.8% in NT. Income variability or risk was similar or the three tillage systems. The most marked difference among tillage systems was in the land area that a farmer can manage, which was four times greater with NT compared to MP, and 1.5 times greater with CP. [Copyright &y& Elsevier]

Rapid changes in the social and economic environment in which agriculture is developing, together with the deterioration of the natural resource base threatens sustainability of farm systems in many areas of the world. For vegetable farms in South Uruguay, survival in the long term depends upon the development of production systems able to reduce soil erosion, maintain or improve physical and biological soil fertility, and increase farmer’s income to socially acceptable levels. We propose a model-based explorative land use study to support the re-orientation of vegetable production systems in South Uruguay. In this paper we present a new method to quantitatively integrate agricultural, environmental and socio-economic aspects of agricultural land use based on explicit design objectives. We describe the method followed to design and evaluate a wide variety of land use activities for Canelo´n Grande (South Uruguay) and we illustrate the usefulness of this approach in an ex-ante evaluation of new farming systems using data from 25 farms in this region. Land use activities resulted from systematic combination of crops and inter-crop activities into crop rotations, different crop management techniques (i.e., mechanisation, irrigation and crop protection) and animal production. We identified and quantified all possible rotations and estimated inputs and outputs at crop rotation scale, explicitly considering interactions among crops. Relevant inputs and outputs (i.e., soil erosion, balance of soil organic matter and nutrients, environmental impact of pesticides, labour and machinery requirements, and economic performance) of each land use activity were quantified using different quantitative methods and following the target-oriented approach. By applying the methodology presented in this paper we were able to design and evaluate 336,128 land use activities suitable for the different soil types in Canelo´n Grande and for farms with different availability of resources, i.e., land, labour, soil quality, capital and water for irrigation. After theoretical evaluation, a large subset of these land use activities showed promise for reducing soil erosion, maintaining soil organic matter content of the soil and increasing farmer’s income, allowing improvement of current farming systems in the region and providing a widely diverse set of strategic options for farmers in the region to choose from. This method can be used as a stand-alone tool to explore options at the field and farm scale or to generate input for optimisation models to explore options at the farm or regional scale. [Copyright &y& Elsevier]

Cropping systems in the Midwest USA are evolving as farmers seek labor-efficient designs to capture and use available light and precipitation. Heavy reliance on fossil fuels and other energy-intensive production inputs coupled with uncertain markets for commodities have encouraged the search for greater energy efficiency as well as alternative crops, markets, and production systems. Agroecology has emerged as an innovative and integrative approach to evaluating systems more suited to the often harsh and unpredictable environment, using native prairie structure and function as one guide to design of future systems. A more specific approach, Natural Systems Agriculture, is being explored as a new paradigm to saving soil while producing the crop and animal output needed for a growing global population. Whole-farm and landscape- level design and planning will become more important as society recognizes and values multifunctional rural landscapes. [ABSTRACT FROM PUBLISHER]