Agronomy for Sustainable Development最新文献

Reconnecting neighboring specialized crop farms and livestock farms through exchanges of grain, fodder, crop by-products, and manure or grazing animals could be a solution to address limiting factors such as labor organization at the farm level. Despite such potential interests, this kind of collective organization rarely occurs and few initiatives are documented. We here documented existing crop-livestock collaborations and examined perceptions of local actors (including farmers) on their advantages and disadvantages, and potential for mainstreaming. To this end, we focused on a case study in southern France in which livestock were reintegrated in a specialized vineyard region and that involved multiple actors beyond farmers (e.g., farm advisers, municipal and cooperative representatives) and types of land use, such as arable land, vineyards, and scrubland. We conducted and analyzed 27 semi-directed interviews to understand the perceptions of the multiple actors involved. We highlighted the diversity of local partnerships between crop farmers, vine growers, and livestock farmers, including shepherds. Our research documents for the first time the complexity of these organizational systems for reintegrating livestock in a vineyard region, beyond only farmers. Existing coordination systems between crop farmers, vine growers, and shepherds or other livestock farmers provide several advantages for soil quality and management of weeds, interrows, or cover crops. Farmers, advisers, and regional agency representatives have a relatively positive perception of such collaborations and the role of livestock; however, most local cooperative representatives do not consider them relevant and do not encourage them. We highlighted a lack of coordination between farmers and of financial support for shepherds. Strengthening ties with policymakers and researchers could support these agroecological initiatives. Training and funding landscape facilitators and creating targeted policies would allow cross-sectorial options, enhancing rural development while managing the risk of wildfires.

Alternative cropping systems can sustain productivity and reduce impacts (e.g., excessive groundwater exploitation, nitrogen losses), but microclimate impacts in diversified systems are mostly unexplored. The aim of this study was to explore innovative cropping systems to reduce water use and nitrogen losses across different precipitation gradients. The well–calibrated Agricultural Production Systems sIMulator (APSIM) model and life cycle assessment were combined to analyze the water and nitrogen footprints of five alternative cropping systems, namely, spring maize–winter fallow (sM–F), winter wheat–summer fallow (WW–F), winter wheat–summer maize–winter fallow–spring maize (WW–M–sM), ryegrass–spring maize (R–sM) and winter wheat–summer maize (WW–M) in the North China Plain from 1980 to 2020. Our findings indicate the total water footprint (m³/10³ MJ) followed the order: WW–F (70) > WW–M (43) = sM–F (43) > R–sM (42) > WW–M–sM (41), while the total nitrogen footprint (g N–eq/10³ MJ) followed a different order: WW–F (423) > WW–M (335) > R–sM (246) > WW–M–sM (212) > sM–F (96). Green and blue water footprints were the primary contributors to the total water footprint for all cropping systems, but the proportion of grey water footprint increased across the precipitation gradient due to higher nitrate leaching. Ammonia volatilization and nitrate leaching were the primary factors contributing to nitrogen losses for all cropping systems, depending on drainage and N application. The most promising alternative cropping systems for sustaining groundwater use and mitigating nitrogen losses shift from sM–F and WW–M–F at dry sites to R–sM at wet sites. These findings highlight the importance of diversifying cropping system to the local climate, offering a scientific basis for green agriculture development across diverse regions in China.

Cereal/legume intercropping enables complementary nitrogen (N) uptake, whereas relay intercropping allows temporal complementarity. However, how these mechanisms contribute to N uptake under moderate, species-tailored N fertilization remains unclear, and clarifying this could inform intercropping practices aligned with Good Agricultural Practices in Europe. We therefore determined N uptake of maize (Zea mays L.), wheat (Triticum aestivum L.), faba bean (Vicia faba L.), and pea (Pisum sativum L.) in six bi-specific strip intercrops and corresponding monocrops. We compared relay intercrops involving maize (late sown) with simultaneous intercrops without maize, across cereal/legume, cereal/cereal, and legume/legume combinations. All species received locally recommended fertilizer amounts for conventional agriculture in the Netherlands. In relay strip intercrops, the early-sown wheat, faba bean, and pea had higher N uptake than the respective monocrops, especially in the border rows of strips. Maize N uptake increased when intercropped with wheat or pea in a year with substantial temporal complementarity. Intercropping with faba bean did not result in increased N uptake for either cereals or pea. Relay intercrops showed land equivalent ratios for N uptake and fertilizer N equivalent ratios mostly above one, while for simultaneous intercrops these were mostly close to one. Therefore, relay intercrops used land more efficiently for N uptake and saved fertilizer N for yield compared to monocrops, whereas simultaneous intercrops did not. We investigated, for the first time, the relative importance of temporal complementarity and cereal-legume N acquisition complementarity for N uptake in strip intercropping under conventional European agriculture, showing that complementary N uptake was strongly associated with temporal complementarity. While inclusion of legumes in intercropping was not required to achieve complementary N capture, it allowed for reduced N input. Relay strip intercropping with species-tailored N input is a pathway toward more sustainable N use in agriculture that can complement cereal-legume complementarity.

Agriculture is increasingly affected by climate change but is also a significant contributor of greenhouse gas (GHG) emissions. This global study aims to find evidence on the impact of agroecological practices on climate change mitigation, namely GHG emissions (CO₂, N₂O, and CH₄) and carbon sequestration. We used a rapid review methodology, screening more than 16,000 publications to retrieve evidence on the implementation of multiple agroecological practices on climate mitigation, for which a knowledge gap exists. We addressed the positive, negative, and inconclusive effects of agroecological multi-practices on climate change mitigation as compared to conventional counterparts. The results of the review indicate that (1) multiple agroecological practices are often associated with statistically significant positive climate change mitigation outcomes across the broad range of evaluated metrics (46% positive, 13% negative, <1% inconclusive outcomes). For all four metric types, there were always more positive than negative outcomes. (2) Within GHG emissions, the highest share of positive outcomes was for CO₂ with 0.69 followed by N₂O (0.67). For carbon stock, positive significant results dominated with 70%, whereas significant negative outcomes were reported for only 7%. (3) For 28% of all metrics, no statistical tests were used or not applied for the combination of practices, resulting in 57% positive, 31% negative, and 11% inconclusive outcomes. (4) A general trend with more positive outcomes with increasing number of agroecological practices was found for carbon sequestration but not for GHG emissions metrics. (5) The majority of studies focused on arable systems, where many metrics showed positive outcomes in particular for carbon sequestration; however, a considerable number of negative outcomes were found for CO₂ and CH₄ emissions, particularly in rice. Although the results of this review show more positive outcomes with multiple agroecological practices, there are trade-offs, e.g., between carbon sequestration (positive effect) and GHG emissions (negative effect).

Vertical farming is gaining attention as an indoor growing system because it enables standardised and intense production, thanks to fully controlled growing settings where environmental parameters can be precisely tuned to satisfy plants’ needs. While vertical farming is claimed to feature high use efficiencies of land, water, and nutrient resources, its high energy use is behind some recent major bankruptcies and hinders large-scale uptake of the technology. Thus, a critical analysis of the productive, economic, and environmental performances of vertical farming is needed. Here, we review the state of the art of vertical farming, with the aim to provide quantitative data on productivity and environmental performance, with a focus on resource use efficiency, which can also be used for benchmarking. The article elaborates on how vertical farming compares with open-field and greenhouse production of leafy greens (in particular lettuce). Lettuce yield (as fresh weight, FW, per cultivation area) in vertical farms commonly averages 60 to 105 kg FW m⁻² year⁻¹, with energy use efficiency of approximately 0.08–0.13 kg FW kWh⁻¹, and water use efficiency of approximately 140 g FW L⁻¹ H₂O. The higher greenhouse gas emissions of vertical farming technology systems (on average, 2.9 kg CO₂ kg⁻¹ FW) as compared with traditional systems are discussed and compared to impacts associated with transport in longer supply chains or those caused by energy-intensive greenhouse technologies that enable cultivation in harsh environments. The potential for consistent production throughout seasons in vertical farming suggests that looking at yearly yield only (rather than their monthly trends) may be misleading when addressing a stable food supply in a specific region.

As a high-value crop, olives are widely cultivated in Mediterranean-climate regions, including California. However, appropriate nitrogen (N) fertilization and nutrient management are required for the sustainable cultivation of olives, particularly in the rapidly adopted super-high-density systems. Identifying the N requirements for super-high-density olive orchards is essential for maximizing yield, improving olive quality, and enhancing soil health to achieve sustainability goals. Despite the importance of such information, there is a lack of recent research in this area. To address this gap, we conducted a two-year study at two super-high-density olive orchards in California’s Central Valley, using an isotopic approach not previously applied in field-grown olives, to understand how N fertilization strategies and soil health management practices, such as compost utilization, affect N uptake, olive yield, and oil quality. The findings were then used to elucidate the N requirements of super-high-density olives in order to revise N application guidelines tailored to growers adopting super-high-density systems. Our results showed no consistent effect of reduced N application rate on yield or oil quality, while compost amendments increased the uptake of fertilizer-derived N by olive trees in the first year. These findings suggest that, depending on the ability of the soil to provide sufficient nutrients, synthetic N fertilizer use in super-high-density orchards could be reduced without compromising yield or oil quality. Furthermore, compost amendments show promise as a sustainability strategy, potentially improving fertilizer N retention and reducing losses.

Variety mixtures represent a promising option to sustainably increase the productivity of grain crops, but the underlying processes driving potential yield benefits remain poorly understood. Notably, the role of variety-specific phenotypic changes in mixtures — defined here as plasticity — and their effects on plant-plant interactions have scarcely been evaluated. Here, we examined the trait responses of eight Swiss wheat varieties when grown in mixtures, and how these plastic changes contributed to overyielding, that was further partitioned into complementarity and selection effects for the first time in wheat mixtures under real conditions. For this, we conducted an outdoor field experiment over three years and at three sites, where wheat varieties were grown in 2-way mixtures and in pure stands. We used a visual criterion (awns) to differentiate individuals of the different varieties in mixtures. We found significant plastic changes in response to mixing for several traits in seven varieties. Furthermore, mixture-induced plasticity in ear density was the main driver of overyielding, itself largely dominated by complementarity effects. An additional experiment allowed us to positively link plasticity in ear density to the speed of tillering onset under shading. This study improves our understanding of the plastic processes fostering overyielding in variety mixtures and provides a key criterion — tillering onset under shade — as a potential breeding target for cultivars for mixtures.

Pesticides have caused significant losses of biodiversity and pose a threat to human health. Crop diversification is proposed as a major solution to achieve the needed pesticide reduction in agriculture, by moderating the pressure of weeds, insect pests, and fungal diseases. According to the pest triangle framework, the impact of a pest outbreak depends on the interactions between crop, pest, and the environment. Diversifying crop sequences in a cropping system could impact the interactions between the three factors and recalibrate the need for pesticides to control pests and avoid yield losses. A previous study found that pesticide use, measured by the Treatment Frequency Index at the cropping system level, is affected both by crop species and crop diversity (assessed in this study through the number of crops), with crop species having a greater impact. However, to our knowledge, no study has quantified the role of the farming environment in the effect of crop diversity on regulating pest pressure, and limiting the need for pesticides. In this study, we used the classification and regression trees method to identify six clusters of production situations with contrasting levels of pesticide use, taking into account the nature of crop species grown. Our results show that production situations, the crop species, and crop diversity, jointly shaped pesticide reliance at the cropping system level. Specifically, production situations explained 5.6% of the variance in total pesticide use. Crop diversification by adding one extra crop reduced total Treatment Frequency Index by 0.10, after filtering out the influences of production situation, and this effect was significant across all pesticide groups, namely herbicides, fungicides, and insecticides. Our findings provide evidence that increasing crop diversity consistently reduces pesticide reliance across diverse production conditions. These insights highlight the potential of crop diversification as an effective and scalable strategy for sustainable pest management.

Genotype mixtures are multiple crop lines grown together to improve yield, stability, and disease control by utilizing different genetic and morphological traits. Incorporating heritage germplasm may enable exploitation of low input adaptation traits while retaining the high yield of elite modern cultivars. However, the effects of nutrient application, sowing density, and disease management on competition/facilitation dynamics in genotype mixtures with diverse germplasms, such as landraces, remain largely unknown. A set of complimentary plot experiments, undertaken in the arable cropping area of the east of Scotland, assessed genotype mixtures using heritage lines and/or elite cultivars of both spring and winter barley. The experimental systems manipulated the sowing densities, mixture composition, nitrogen application, and fungal disease pressure across three different field seasons. Here we show that the advantages of genotype mixtures were highly dependent on the genotypic makeup of the mixture and the environmental conditions in which they are grown, demonstrating complex genotype mixture × environment interactions. Genotype mixture performance in barley is highly dependent on the interaction of genetic composition and management factors. This paper revealed, for the first time, that small amounts of heritage germplasm enhanced yield stability, though overall yields rarely match those of the elite monocultures and no consistent disease reduction was observed. Although barley gains limited benefits from mixing genotypes, our study is able to highlight complex trends in mixture composition and environment that are relevant for crops with greater genotype mixture yield benefits.