Agroecosystem Resilience Research Articles

Análisis bibliométrico del conocimiento científico sobre resiliencia de agroecosistemas

Global phenomena such as climate change threaten the resilience of agroecosystems and therefore food security. Thus, the objective of this paper was to analyze the cumulative nature and outstanding advances in the knowledge of the resilience of agroecosystems as a basis for the development of new trends in the subject. A literature review was conducted using the Web of Science database, considering criteria such as date of publication, disciplines and scientific journals. The search covers the period from 1993 to 2020. One hundred eighty-eight publications were identified, with 2018 and 2019 being the years with the highest number of articles published. The research areas with the most publications on resilience are ecology (71), agriculture (52) and environmental sciences (44). Regarding the connectivity based on the value of intermediate centrality, the areas of greatest interrelationship are mainly: agriculture (0.45), science and technology (0.28), environmental sciences (0.2) and ecology (0.12). In the dynamics and study of resilience, the adaptability of the agroecosystem stands out. The conceptual model of resilience analyzed facilitates its study and is composed of: precariousness, latitude, resistance and panarchy. Therefore, the indicators for quantifying resilience in agroecosystems are heterogeneous and multidimensional. It is concluded that resilience has been conceptually studied as an emerging property from the agroecological approach, recently from the socioecological systems approach, where adaptability and interdiscipline are highlighted as a means to solve complex problems.

Detecting Winter Cover Crops and Crop Residues in the Midwest US Using Machine Learning Classification of Thermal and Optical Imagery

Cover crops are an increasingly popular practice to improve agroecosystem resilience to climate change, pests, and other stressors. Despite their importance for climate mitigation and soil health, there remains an urgent need for methods that link winter cover crops with regional-scale climate mitigation and adaptation potential. Remote sensing is ideally suited to provide these linkages, yet, cover cropping has not been analyzed extensively in remote sensing research. Methods used for remote sensing of crops from satellites traditionally leverage the difference between visible and near-infrared reflectance to isolate the signal of photosynthetically active vegetation. However, using traditional greenness indices like the Normalized Difference Vegetation Index (NDVI) for remotely sensing winter vegetation, such as winter cover crops, is challenging because vegetation reflectance signals are often confounded with reflectance of bare soil and crop residues. Here, we present new and established methods of detecting winter cover crops using remote sensing observations. We find that remote sensing methods that incorporate thermal data in addition to traditional reflectance metrics are best able to distinguish between winter farm management practices. We conclude by addressing the potential of existing and upcoming hyperspectral and thermal missions to further assess agroecosystem function in the context of global change.

Climate Resilient Vegetable Farming: A Review

Climate change is one of the global challenges faced by the mankind today with the continuously rising temperature, triggering a host of extreme weather events such as heat waves, drought, and flooding. These climate induced challenges are manifesting themselves rapidly, causing socio-economic insecurities and health challenges, particularly in marginalized communities. There is increasing evidence of indirect associations between climate change and the rise in the rates of malnutrition, poor health, hunger and starvation, as well as food and water insecurity. In addition, climate-change impacts have put an additional pressure on already stressed natural resource base, reducing the resilience of agro-ecosystems that are, in part, providing food and nutritional security in rural communities. Tackling these challenges requires a paradigm shift from the current incremental adaptation strategies towards transformative alternatives that also place an equal emphasis on human nutrition and health, as well as environmental sustainability. In the context of marginalized farming communities, a transformative adaptation strategy is defined as one that causes a disruptive, but desirable and sustainable change to the social– ecological state of the system. In the context of this paper, the inclusion of adaptable nutrient dense vegetable crops into marginalized agricultural systems and dominant food systems is considered part of transformative adaptation.

Keystone taxa-mediated bacteriome response shapes the resilience of the paddy ecosystem to fungicide triadimefon contamination

The increasing input of fungicides has emerged as a global concern for agroecosystem stability and sustainability. Agroecosystem resilience has been linked to microbiome response, however, is not well understood. Focusing on a widespread triazole-class fungicide triadimefon in the paddy ecosystem, we characterized that the soils and sediments were dominant triadimefon reservoirs with the peak level at 195 μg kg−1 and 31.3 μg kg−1, respectively, but essential for the resilience of paddy ecosystem to triadimefon. In paddy simulation models, the half-life of triadimefon in soil-sediment was 8.4–28.9 days, while it was prolonged to 86.6–115.5 days after elimination of resident microbial community. Phospholipid fatty acid profiling and high-throughput sequencing showed that the distinctive bacterial community responses contributed to variable degradation of triadimefon in paddy soils and sediments. Sphingomonas and Xanthomonas were identified as positive responders of the keystone taxa in the responsive bacteriome, whereas Enterobacter were negative responders that declined over time. Synthetic assemblages combined with quantitative polymerase chain reaction further validated that Sphingomonas and Xanthomonas were involved in sustaining soil-sediment resilience to triadimefon contamination. Collectively, our results revealed that the shaping of soil and sediment bacteriomes was responsible for the resilience of the paddy agroecosystem to fungicide contamination.

Using network ecology to understand and mitigate long‐term insect declines

Using network ecology to understand and mitigate long‐term insect declines

Potential Use of Beneficial Microorganisms for Soil Amelioration, Phytopathogen Biocontrol, and Sustainable Crop Production in Smallholder Agroecosystems

Smallholder agroecosystems play a key role in the world's food security providing more than 50% of the food produced globally. These unique agroecosystems face a myriad of challenges and remain largely unsupported, yet they are thought to be a critical resource for feeding the projected increasing human population in the coming years. The new challenge to increase food production through agricultural intensification in shrinking per capita arable lands, dwindling world economies, and unpredictable climate change, has led to over-dependence on agrochemical inputs that are often costly and hazardous to both human and animal health and the environment. To ensure healthy crop production approaches, the search for alternative ecofriendly strategies that best fit to the smallholder systems have been proposed. The most common and widely accepted solution that has gained a lot of interest among researchers and smallholder farmers is the use of biological agents; mainly plant growth promoting microorganisms (PGPMs) that provide essential agroecosystem services within a holistic vision of enhancing farm productivity and environmental protection. PGPMs play critical roles in agroecological cycles fundamental for soil nutrient amelioration, crop nutrient improvement, plant tolerance to biotic and abiotic stresses, biocontrol of pests and diseases, and water uptake. This review explores different research strategies involving the use of beneficial microorganisms, within the unique context of smallholder agroecosystems, to promote sustainable maintenance of plant and soil health and enhance agroecosystem resilience against unpredictable climatic perturbations.

Influence of conservation tillage on Greenhouse gas fluxes and crop productivity in spring-wheat agroecosystems on the Loess Plateau of China.

The effects of climate change such as dry spells, floods and erosion heavily impact agriculture especially smallholder systems on the Northwestern Loess Plateau of China. Nonetheless agriculture also contributes to global warming through the emission of greenhouse gases such as CO2, CH4 and N2O. Yet this complex conundrum can be alleviated and mitigated through sound soil and water management practices. Despite considerable literature on Conservation Agriculture (CA) as a strategy to improve the resilience and mitigation capacity of agroecosystems, there is still paucity of information on the impacts of CA on crop production and environmental quality on the Plateau. In order to fill this gap this study examined the effects of no-till and straw mulch on crop productivity and greenhouse gas fluxes in agroecosystems on the Plateau where farmers’ common practice of conventional tillage (CT) was tested against three CA practices: conventional tillage with straw mulch (CTS), no-till (NT) and no-till with straw mulch (NTS). The results indicated that all three CA practices (CTS, NT and NTS) markedly increased soil water content (SWC), soil organic carbon (SOC) and soil total nitrogen (STN) but reduced soil temperature (ST). Average grain yields were 854.46 ± 76.51, 699.30 ± 133.52 and 908.18±38.64 kg ha-1 respectively under CTS, NT and NTS indicating an increase by approximately 33%, 9% and 41% respectively compared with CT (644.61 ± 76.98 kg ha−1). There were significant (p < 0.05) reductions of Net CO2 emissions under NT (7.37 ± 0.89 tCO2e ha−1y−1) and NTS (6.65 ± 0.73 tCO2e ha-1y-1) compared with CTS (10.65 ± 0.18 tCO2e ha−1y−1) and CT (11.14 ± 0.58 tCO2e ha−1y−1). All the treatments served as sinks of CH4but NTS had the highest absorption capacity (−0.27 ± 0.024 tCO2e ha−1y−1) and increased absorption significantly (p < 0.05) compared with CT (−0.21 ± 0.017 tCO2e ha−1y−1); however, CA did not reduce emissions of N2O. These had an influence on Global warming potential (GWP) as NT and NTS resulted in significant reduction in net GWP. Grain yield was significantly correlated positively with SOC and STN (p < 0.05); ecosystem respiration was also significantly correlated with SWC and ST while CH4 flux was highly correlated with ST (p < 0.001). Crop yield and GHG responses to CA were controlled by soil hydrothermal and nutrient changes, thus improving these conditions through adoption of sustainable soil moisture improvement practices such as no-till, straw mulch, green manuring, contour ploughing and terracing can improve crop resilience to climate change and reduce GHG emissions in arid and semi-arid regions.

Conservation management improves agroecosystem function and resilience of soil nitrogen cycling in response to seasonal changes in climate.

Understanding how conservation agricultural management improves soil nitrogen (N) stability in the face of climate change can help increase agroecosystem productivity and mitigate runoff, leaching and downstream water quality issues. We conducted a 2-year field study in a 36-year-old rain-fed cotton production system to evaluate the impacts of changing climatic factors (temperature and precipitation) on soil N under conservation management, including moderate inorganic N fertilizer application (0 and 67kgNha-1), winter cover crops (fallow; winter wheat, Triticum aestivum L.; hairy vetch, Vicia villosa Roth), and reduced tillage (no-till; disk tillage). Structural equation modeling (SEM) was used to quantify and compare the effects of conservation management and climatic factors on soil N concentrations. Fertilizer and vetch cover crops increased soil total N concentration by 16% and 18%, respectively, and also increased microbial N transformation rate by 41% and 168%. In addition, vetch cover crops also increased soil labile N concentrations by 57%, 21%, and 79%, i.e., extractable organic N, ammonium, and nitrate, respectively. The highest soil δ15N value (6.4±0.3‰) was observed under the 67kgNha-1 fertilizer-wheat-disk tillage treatment, and the lowest value (4.8±0.3‰) under the zero-fertilizer-wheat-no-till treatment, indicating fertilizer and tillage might accelerate microbial N transformation. The SEM showed positive effects of temperature and precipitation on labile N concentrations, suggesting destabilization of soil N and the potential for soil N loss under increased temperature and intensified precipitation. Fertilizer and vetch use might mitigate some of the effects of temperature by accelerating microbial N transformations, with vetch having a larger effect than fertilizer (0.35 vs. 0.15, Table 1). No-till can reduce some of the effects of precipitation on soil labile N by maintaining soil structure. Our study suggests that fertilizer, vetch cover crop, and no-till might help improve function and resilience of agroecosystems in relation to soil N cycling. Soil N stabilization in cropping systems can be enhanced by adjusting agricultural management.

Hybrid coffee cultivars may enhance agroecosystem resilience to climate change.

Anthropogenic climate change is predicted to cause shifts in temperature and precipitation patterns that will be detrimental for global agriculture. Developing comprehensive strategies for building climate resilient agroecosystems is critical for maintaining future crop production. Arabica coffee (Coffea arabica) is highly sensitive to the quantity and timing of precipitation, so alterations in precipitation patterns that are predicted under climate change are likely to be a major challenge for maintaining coffee agroecosystems. We assessed cultivar selection as a potential component of more resilient coffee agroecosystems by evaluating water stress responses among five Arabica coffee cultivars (clonal hybrids H10 and H1 and seedling lines Catuai 44, Catuai, and Villa Sarchi) using a precipitation reduction experiment in the highlands of Tarrazú, Costa Rica. During the first harvest (eighteen months after planting), plants under the rainout treatment had 211 % greater total fruit weight and over 50 % greater biomass than under the control treatment, potentially due to protection from unusually high rainfall during this period of our experiment. At the second harvest (30 months after planting), after a year of more typical rainfall, plants under rainout still produced 66 % more fruit by weight than under control. The magnitude of the responses varied among cultivars where, at the first harvest, H10 and H1 had approximately 92 % and 81 % greater fruit production and 18 % and 22 % greater biomass, respectively, and at the second harvest H10 had 60 % more fruit production than the overall average. Thus, our findings suggest that the hybrid lines H10 and H1 are more resilient than the other cultivars to the stress of high soil moisture. Overall, our results indicate that stress due to higher than average rainfall could impair coffee plant growth and production, and that cultivar selection is likely to be an important tool for maintaining the viability of coffee production, and the resilience of global agroecosystems more generally, under climate change.

Unlocking the inherent potential of plant genetic resources: food security and climate adaptation strategy in Fiji and the Pacific.

Pacific Island Countries (PICs) are the center of origin and diversity for several root, fruit and nut crops, which are indispensable for food security, rural livelihoods, and cultural identity of local communities. However, declining genetic diversity of traditional food crops and high vulnerability to climate change are major impediments for maintaining agricultural productivity. Limited initiatives to achieve food self-sufficiency and utilization of Plant Genetic Resources (PGR) for enhancing resilience of agro-ecosystems are other serious constraints. This review focuses on the visible and anticipated impacts of climate ge, on major food and tree crops in agriculture and agroforestry systems in the PICs. We argue that crop improvement through plant breeding is a viable strategy to enhance food security and climatic resilience in the region. The exploitation of adaptive traits: abiotic and biotic stress tolerance, yield and nutritional efficiency, is imperative in a world threatened by climatic extremes. However, the insular constraints of Fiji and other small PICs are major limitations for the utilization of PGR through high throughput techniques which are also cost prohibitive. Crop Improvement programs should instead focus on the identification, conservation, documentation and dissemination of information on unique landraces, community seed banks, introduction of new resistant genotypes, and sustaining and enhancing allelic diversity.

COVID-19 Pandemic and Agroecosystem Resilience: Early Insights for Building Better Futures

The way the COVID-19 pandemic disrupted human lives and livelihoods constituted a stress test for agroecosystems in developing countries, as part of rural–urban systems and the global economy. We applied two conceptual schemes to dissect the evidence in peer-reviewed literature so far, as a basis for better understanding and enabling ‘building back better’. Reported positive impacts of the lockdown ‘anthropause’ on environmental conditions were likely only short-term, while progress towards sustainable development goals was more consistently set back especially for social aspects such as livelihood, employment, and income. The loss of interconnectedness, driving loss of assets, followed a ‘collapse’ cascade that included urban-to-rural migration due to loss of urban jobs, and illegal exploitation of forests and wildlife. Agricultural activities geared to international trade were generally disrupted, while more local markets flourished. Improved understanding of these pathways is needed for synergy between the emerging adaptive, mitigative, transformative, and reimaginative responses. Dominant efficiency-seeking strategies that increase fragility will have to be re-evaluated to be better prepared for further pandemics, that current Human–Nature interactions are likely to trigger.

Enhancing integration of Indigenous agricultural knowledge into USDA Natural Resources Conservation Service cost-share initiatives

Agricultural management practices drawn from Indigenous agricultural knowledge (IAK) have supported people in the North American desert Southwest for thousands of years. Techniques developed and refined from generation to generation through careful observation and innovation have enhanced the sustainability and resilience of these delicate agroecosystems over millennia. USDA Natural Resources Conservation Service (NRCS) recognized the contributions of IAK practices to Environmental Quality Incentives (EQIP) and the Conservation Stewardship Programs (CSP) in the 2010 <i>Indigenous Stewardship Methods and NRCS Conservation Practices</i> (ISM) handbook. However, during fiscal year 2017 2% of EQIP and CSP contracts went to American Indian farms, which make up 2.9% of the total farms in the United States. NRCS would need to award nearly 400 more contracts to Indigenous farms to achieve proportional representation. This suggests significant potential exists for expanding American Indian participation in these conservation programs but barriers to their participation remain. For example, agriculturalists who wish to employ IAK management practices must go through an ad hoc process defined in the 2010 ISM handbook. This adds further complexity to the application process, in which applicants must navigate unique land tenure/ownership issues and tribal/federal interactions. Here we present examples of Indigenous conservation practices embedded in agricultural systems of Hopi dryland farmers, the La Courte Oreilles Band of Lake Superior Chippewa wild rice (<i>Zizania palustris</i>) harvesters, and Menominee tribal foresters to demonstrate the compatibility of IAK practices with NRCS conservation outcomes and to argue for full inclusion of Indigenous agricultural practices into something equivalent to the NRCS Field Office Technical Guides. Expansion of Indigenous agriculturalists and producers in NRCS programs can help preserve important ecosystems and help support Indigenous cultures and time-tested concepts of stewardship. Incorporation and support of IAK practices is beneficial to all stakeholders because expansion of partnerships between the NRCS and Indigenous agriculturalists and producers will help expand Indigenous conservation and agriculture practices and further the NRCS mission of “Helping People Help the Land.”

Using fall‐seeded cover crop mixtures to enhance agroecosystem services: A review

AbstractThe intensification of agriculture has resulted in the loss of species diversity in agroecosystems. Crop diversification not only improves ecosystem functions but increases agroecosystem resilience to climate change. Cover crops (CC) are used in the crop rotation to increase plant diversity and provide continuous living roots and soil cover. Previous studies have focused mainly on pure stands of CC and on binary mixtures. In recent years, there has been a growing interest in multispecies mixtures (&gt;2 species). Here, we review reports from the literature to document the effectiveness of fall‐seeded CC mixtures to provide agroecosystem services such as weed suppression, N cycling, soil organic C storage, and crop productivity. We cover both organic and conventional field crop systems in North America and Europe. We found, for both systems, that fall‐seeded CC mixtures increased many agroecosystem services compared with a control without CC; however, they had inconsistent effects in comparison with a pure stand. The capacity of mixtures to enhance a given agroecosystem service was found to be dependent on the species functional group. Legume‐based mixtures increased soil N and C contents along with crop yield, whereas nonlegume mixtures improved N recycling and weed suppression. Differences in the functional groups within CC mixtures could lead to trade‐offs among agroecosystem services. Future research should focus on what drives species‐specific contributions to productivity and other ecosystem services when CC are seeded in mixtures. More long‐term research is needed to provide better insights into the stability of the ecosystem services provided by CC mixtures.

Public Policies for the Development of Agroecosystems Resilient to Climate Change

Objective: Analyze public policies in Mexico facing climate change in agriculture that allow the development of resilient agroecosystems. Design/methodology/approach: An analysis of research on resilience to climate change in the agricultural and rural sectors, as well as analysis of literature on public policies formulated to climate change in the agricultural sector (period 2013-2019), was realized. Results: Multiple sources of resilience for agroecosystems are present. Policies could be oriented to identify such sources and to strengthen capacities according to different scales and contexts. There is the possibility of considering factors associated with the evolution of these systems to employ strategies that are consistent and that allow coordination between political levels. Limitations of the study/Implications: This is a theoretical study restricted to the available literature published until 2019. Findings/Conclusions: Public policies require integrating the perspective of the dynamics of the complex agricultural system and the multiple sources of resilience at different scales and contexts, articulating the development of resilient agroecosystems to climate change.

Maize-Pigeonpea Intercropping Outperforms Monocultures Under Drought

There is an urgent need to develop resilient agroecosystems capable of helping smallholder farmers adapt to climate change, particularly drought. In East Africa, diversification of maize-based cropping systems by intercropping with grain and tree legumes may foster productivity and resilience to adverse weather conditions. We tested whether intercropping enhances drought resistance and crop and whole-system yields by imposing drought in monocultures and additive intercrops along a crop diversity gradient—sole maize (Zea mays), sole pigeonpea (Cajanus cajan), maize-pigeonpea, maize-gliricidia (Gliricidia sepium, a woody perennial), and maize-pigeonpea-gliricidia—with and without fertilizer application. We developed and tested a novel low-cost, above-canopy rainout shelter design for drought experiments made with locally-sourced materials that successfully reduced soil moisture without creating sizeable artifacts for the crop microenvironment. Drought reduced maize grain yield under fertilized conditions in some cropping systems but did not impact pigeonpea grain yield. Whole-system grain yield and theoretical caloric and protein yields in two intercropping systems, maize-pigeonpea and maize-gliricidia, were similar to the standard sole maize system. Maize-pigeonepea performed most strongly compared to other systems in terms of protein yield. Maize-pigeonpea was the only intercrop that consistently required less land than its corresponding monocultures to produce the same yield (Land Equivalent Ratio &amp;gt;1), particularly under drought. Despite intercropping systems having greater planting density than sole maize and theoretically greater competition for water, they were not more prone to yield loss with drought. Our results show that maize-pigeonpea intercropping provides opportunities to produce the same food on less land under drought and non-drought conditions, without compromising drought resistance of low-input smallholder maize systems.

316 Regenerative grazing: restoring ecosystem function to improve farm profits

Abstract I explore the hypothesis that managing grazing using regenerative grazing principles to improve soil health is a sustainable base to improve net farm profits. Carbon-rich soil is healthy soil and beneficial for the entire ecosystem. Changing current unsustainable high-input agricultural practices to low-input practices that regenerate ecosystem function will be necessary for sustainable, resilient agro-ecosystems. Current reductionist, small-scale, short-term research managed without goals to find what management framework will deliver positive outcomes for ranchers has produced very erroneous conclusions. Healthy ecosystems function by increasing soil carbon to improve water infiltration and retention; soil nutrient access and retention; and the diversity of fungi, microbes, plants, insects, and wildlife that contribute to both improved livestock nutrition and human nutrition. I will give an overview of our research endeavors using a systems-science, multi-discipline framework to find the best grazing management for regenerating: soil health and function; delivery of ecosystem goods and services; and farmer livelihoods and social resilience. To accomplish this, we partner with farmers who have improved the environment and excel financially to convert experimental results into sound environmental, social, and economic benefits regionally and globally.

Evaluating the Untapped Potential of U.S. Conservation Investments to Improve Soil and Environmental Health

There is increasing enthusiasm around the concept of soil health, and as a result, new public and private initiatives are being developed to increase soil health-related practices on working lands in the United States. In addition, billions of U.S. public dollars are dedicated annually toward soil conservation programs, and yet, it is not well quantified how investment in conservation programs improve soil health and, more broadly, environmental health. The Environmental Quality Incentives Program (EQIP) is one of the major U.S. public conservation programs administered on privately managed lands for which public data are available. In this research, we developed a multi-dimensional classification system to evaluate over 300 EQIP practices to identify to what extent practices have the potential to improve different aspects of soil and environmental health. Using available descriptions and expert opinion, these practices were evaluated with a classification system based on the practice's potential to exhibit the following environmental health outcomes: (i) principles of soil health to reduce soil disturbance and increase agrobiodiversity; (ii) a transition to ecologically-based management to conserve soil, water, energy and biological resources; and (iii) adaptive strategy to confer agroecosystem resilience. Further, we analyzed nearly $7 billion U.S. dollars of financial assistance dedicated to these practices from 2009 through 2018 to explore the potential of these investments to generate environmental health outcomes. We identified nine practices that fit the highest level of potential environmental health outcomes in our classification systems. These included wetlands and agroforestry related practices, demonstrating that ecologically complex practices can provide the broadest benefits to environmental health. Practices with the greatest potential to improve environmental health in our classification system represent 2–27% of annual EQIP funding between 2009 and 2018. In fiscal year 2018, these practices represented between $13 and 121 million, which represented ~0.08% of total annual USDA expenditures. These classifications and the subsequent funding analysis provide evidence that there is tremendous untapped potential for conservation programs to confer greater environmental health in U.S. agriculture. This analysis provides a new framework for assessing conservation investments as a driver for transformative agricultural change.

Sensitivity of the DSSAT model in simulating maize yield and soil carbon dynamics in arid Mediterranean climate: Effect of soil, genotype and crop management

• DSSAT model reasonably well simulates crop and soil variables in arid sandy soils. • Global sensitivity analysis is performed using co-inertia analysis and Sobolʹ method. • Soil input parameters largely control simulation of crop variables in low productive systems. • Carbon related crop management factors significantly contribute to modelled SOC variance. Crop models may potentially explore alternative ways to improve agroecosystem resilience in arid regions of Middle East and North Africa. Mapping the outputs behavior as a function of the inputs and quantifying the uncertainty contribution of inputs to the variability of outputs are crucial for understanding and applying complex mathematical models to a new environment. Objectives of present research are (i) to calibrate and evaluate the Decision Support System for Agrotechnology Transfer (DSSAT) cropping system model using detailed experimental datasets on maize production in arid sandy soils (Entisol) and (ii) to determine the model’s sensitivity to soil, genotype and crop management inputs under the currently explored conditions (low fertility and water holding capacity) based on multivariate analysis and variance decomposition methods. The goodness-of-fit statistics between observed and simulated data indicated that the calibrated model reasonably well simulates maize phenology, growth and yield, evapotranspiration, soil water content, grain N concentration, and postharvest soil NO 3 -N in eight year site field experiments. A global sensitivity analysis using the co-inertia method was carried out to link 14 output variables and 25 soil and genotype input parameters. Maize growth and yield variables were strongly correlated with soil hydrological and fertility input parameters such as soil water upper limit (SDUL) and soil organic carbon (SOC), whereas simulation of maize phenology was largely determined by phenological genotype-specific cultivar input parameters. A strong association was also observed between the output variables of yield and soil fertility. The effect of carbon (C) related soil input parameters of initial SOC and stable SOC and crop management factors of maize residue retention and compost application under no-till system on the long-term (10 years) simulation of yield and SOC dynamics was further explored using Sobolʹ method. Simulated grain yield, water productivity, active SOC, and cumulative soil CO 2 efflux were most sensitive to initial stable SOC and compost application. Maize residue retention significantly affected the simulation of cumulative N mineralization, SOC % in 0.2 m depth, and cumulative soil CO 2 efflux through interactions effect, i.e. total-order sensitivity index ( S Ti ) > 0.05, with other inputs. Compost application increased grain yield by 13 %, SOC stock by 5%, and cumulative soil CO 2 efflux by 95 % compared with no application. However, compost application with maize residue retained significantly reduced cumulative soil CO 2 efflux by 12 % compared with compost application with maize residue removed. Therefore, the application of compost with maize residue retained under no-till system is a plausible crop management option for agronomically improved and environmentally sound maize production in arid sandy soils.

A Midwest USA Perspective on Von Cossel et al.’s Prospects of Bioenergy Cropping Systems for a More Social-Ecologically Sound Bioeconomy

Bioenergy cropping systems afford the prospect to provide a more socially and ecologically sustainable bioeconomy. By creating opportunities to diversify agroecosystems, bioenergy crops can be used to fulfill multiple functions in addition to providing more environmentally benign fuels. Bioenergy crops can be assembled into cropping systems that provide both food and energy and which also provide cleaner water, improved soil quality, increased carbon sequestration, and increased biological diversity. In so doing, they improve the resilience of agroecosystems and reduce risks associated with climate change. Beyond the farmgate, bioenergy crops can improve the economic prospects of rural communities by creating new jobs and providing opportunities for local investment.

Ecological and Nutritional Functions of Agroecosystems as Indicators of Smallholder Resilience

Smallholder agriculture is the foundation of global food systems, yet smallholders face severe socio-economic and environmental challenges that can destabilize livelihoods and threaten their resilience. Given that smallholder farmers rely on household production to meet their nutritional needs, management of soil fertility, biodiversity, and other ecological characteristics of agroecosystems directly affects smallholders’ capacity to produce sufficient crop nutrients for their diets. However, we lack explicit frameworks linking ecological and nutritional functions of agroecosystems, as well as research exploring farmers’ adaptive capacity and agency in mediating these functions, and ultimately, agroecosystem resilience. To address these gaps, we developed an indicator framework to evaluate the complementary roles of ecological and nutritional functions of agroecosystems for smallholder resilience. Paired ecological and nutritional indicators were aggregated into an index representing four agroecosystem functions: (1) Productivity, (2) Diversity, (3) Quality, and (4) Functional Diversity. We then applied this framework and index to a case study of Q’eqchi’ Maya smallholders in eastern Guatemala, using farm management and crop quality data from 60 households to determine the status of agroecosystem functions and assess coping and adaptive capacities in response to shocks. More than three-quarters of farms in the sample relied solely on household production of staples to meet their nutritional demands. Across farms, ecological and nutritional indicators were significantly related (Kendall’s tau = 0.58, z = 5.7, p <0.0001), and we found both synergistic (Quality, Functional Diversity) and tradeoff (Productivity) relationships between indicator pairs. We found that farmers using ecological adaptation strategies such as cover cropping and agroforestry had significantly higher levels of agroecosystem functioning and resilience than farmers who were coping with shocks by working off-farm or renting land from plantations. Our findings demonstrate the importance of linking ecological and nutritional functions of agroecosystems through diversified management practices to leverage their synergies. Because smallholder agroecosystems underlie a third of the food system, understanding and promoting their resilience is critical for the social, ecological, and nutritional well-being of global populations.