Search Results (19)

The Loess Plateau is a typical dryland agricultural region where water scarcity constrains crop production. Plastic film mulching is widely used to mitigate this limitation, but its long-term application has caused soil degradation and environmental pollution, highlighting the need for sustainable alternatives. This study evaluated the effects of post-wheat sequential green manure cropping—common vetch (CV) and winter rape (CR)—on soil water balance, potato yield, water use efficiency (WUE), and economic returns within a winter wheat-potato rotation system. A field experiment (2019–2023) was conducted on the Loess Plateau, comparing CV, CR, plastic film mulching (PM), and no mulching (NM). Soil water content (0–200 cm), evapotranspiration (ET), tuber yield, WUE, and economic performance were measured. Although CV and CR depleted soil water in the 0–100 cm layer during their growth, subsequent fallow precipitation (86 mm) and low soil water loss replenished the deficit, resulting in comparable soil water storage at potato sowing among CV, CR, and NM (518.8, 508.8, and 518.9 mm, respectively). Over the full rotation cycle, a positive soil water balance (63.1–147.5 mm) was maintained across all treatments, indicating no detectable net depletion within the measured 0–200 cm profile over the four potato seasons. Potato tuber yield increased by 61.7% (CV), 52.4% (CR), and 74.8% (PM) relative to NM. The WUE of CV (73.5 kg ha⁻¹ mm⁻¹) and CR (71.5 kg ha⁻¹ mm⁻¹) was comparable to that of PM (74.2 kg ha⁻¹ mm⁻¹) and significantly higher than that of NM (46.1 kg ha⁻¹ mm⁻¹). Net incomes under CV and CR did not differ significantly from PM, while their input costs were lower. Collectively, the integrated system combining post-wheat sequential green manure cropping—particularly with common vetch—and straw mulching represents a technically feasible, economically viable, and environmentally beneficial alternative to plastic film mulching, contributing to sustainable dryland agriculture on the Loess Plateau and analogous semi-arid regions. Full article

Crop rotation systems profoundly influence soil phosphorus (P) dynamics through physicochemical and microbial interactions. The mechanisms regulating P availability under various rotational practices remain poorly understood. This five-year field experiment investigated the effects of four rotation systems (WM: wheat–maize; WP: wheat–peanut; WS: wheat–soybean; MV: maize–hairy vetch) on soil P fractions, phosphatase activities, P-cycling gene abundance, and their interactions with soil properties. The WM rotation substantially reduced soil pH (6.29) while increasing labile P fractions (Ca₂-P) and moderately labile P (Al-P, Fe-P, and Ca₈-P), which was attributed to enhanced acid phosphatase activity. The WP rotation elevated soil pH (8.13) but reduced P availability due to calcium–P immobilization. The MV rotation stimulated microbial P cycling, exhibiting the highest phoD (2.01 × 10⁶ copies g⁻¹) and phnK (33,140 copies g⁻¹) gene abundance, which was linked to green manure-induced microbial activation. Redundancy analysis identified soil pH, total nitrogen, and stoichiometric ratios (C/N and N/P) as key shared drivers of P fractions and enzymatic activity. Partial least squares path modeling (PLS–PM) indicated that crop rotation directly regulated P availability through pH modulation (r = −0.559 ***) and the C/N ratio (r = 0.343 ***) while indirectly regulating P fractions through phosphatase activity. Lower C/N ratios (<10) across all rotation regimes amplified the carbon limitation in the process of P transformation, indicating that exogenous carbon inputs and appropriate stoichiometry in the soil should be optimized. The results of this study inform the selection of suitable crop rotation patterns for sustainable agriculture. Full article

This long-term field study conducted in Yancheng, China, evaluated the effects of diverse crop rotation sequences on rice growth, yield, and soil properties. Six rotation treatments were implemented from 2016 to 2023 as follows: rice–wheat (control), rice–rape, rice–hairy vetch, rice–barley, rice–faba bean, and rice–winter fallow. Rice growth parameters, yield components, biomass accumulation, and soil properties were measured. Results showed that legume-based rotations, particularly rice–faba bean and rice–hairy vetch, significantly improved rice growth and yield compared to the rice–wheat control. The rice–faba bean rotation increased yield by 19.1% to 8.73 t/ha compared to 7.33 t/ha for the control, while rice–hairy vetch increased yield by 11.9% to 8.20 t/ha. These rotations also demonstrated higher biomass production efficiency, with increases of 33.33% and 25.00%, respectively, in spring crop biomass. Soil nutrients improvements were observed, particularly in available nitrogen, potassium, and electrical conductivity. Legume-based rotations increased the available nitrogen by up to 35.9% compared to the control. The study highlights the potential of diversified crop rotations, especially those incorporating legumes, to enhance rice productivity and soil health in subtropical regions. These findings have important implications for developing sustainable and resilient rice-based cropping systems to address challenges of food security and environmental sustainability in the face of climate change and resource constraints. Full article

In the traditional farming systems, the excessive application of chemical fertilizers to boost crop yields has resulted in a range of issues, such as soil quality degradation, soil structure deterioration, and pollution of the farmland ecological environment. Green manure, as a high-quality biological fertilizer source with rich nutrient content, is of great significance for enhancing the soil quality and establishing a healthy farmland ecosystem. However, there are few studies on the effects of different green manures on the soil nutrient levels, enzyme activities, and soil bacterial community composition in the rice–wheat rotation areas in southern China. Thus, we planted Chinese milk vetch (MV; Astragalus sinicus L.), light leaf vetch (LV; Vicia villosa var.), common vetch (CV; Vicia sativa L.), crimson clover (CC; Trifolium incarnatum L.), Italian ryegrass (RG; Lolium multiflorum L.), and winter fields without any crops as a control in the Taihu Lake area of Jiangsu. The soil samples collected after tilling and returning the green manure to the field during the bloom period were used to analyze the effects of the different green manures on the soil nutrient content, enzyme activity, and the structural composition of the bacterial community. This analysis was conducted using chemical methods and high-throughput sequencing technology. The results showed that the green manure returned to the field increased the soil pH, soil organic matter (SOM), alkali-hydrolyzed nitrogen (AN), available phosphorus (AP), available potassium (AK), sucrose (SC), urease (UE), and neutral phosphatase (NEP) contents compared to the control. They increased by 1.55% to 10.06%, 0.26% to 9.31%, 20.95% to 28.42%, 20.66% to 57.79%, 12.38% to 37.94%, 3.11% to 58.19%, 6.49% to 32.99%, and 50.0% to 80.36%, respectively. In addition, the green manure field increased the relative abundance of the genera Proteobacteria and Haliangium while decreasing the relative abundance of Gemmatimonadetes, Chloroflexi, SBR1031, and Anaeromyxobacter in the soil bacteria. Both the number of ASVs (amplicon sequence variants) and α-diversity of the soil bacterial communities were higher compared to the control, and the β-diversity varied significantly among the treatments. Alkali-hydrolyzed nitrogen and neutral phosphatase had the greatest influence on the soil bacterial community diversity, with alkali-hydrolyzed nitrogen being the primary soil factor affecting the soil bacterial community composition. Meanwhile, the results of the principal component analysis showed that the MV treatment had the most significant impact on soil improvement. Our study provides significant insights into the sustainable management of the soil quality in rice–wheat rotations. It identifies MV as the best choice among the green manure crops for improving the soil quality, offering innovative solutions for reducing chemical fertilizer dependence and promoting ecological sustainability. Full article

Intensive agriculture has created several problems in cropping systems that threaten the sustainability of agricultural production. In order to design new cropping systems, a new approach is emerging to support the transition toward sustainable agriculture: a co-design and co-evaluation process that involves stakeholders in the agrifood chain. The present work therefore describes the co-design and co-evaluation process that was followed to design a highly diversified cropping system in a Mediterranean environment. The different systems that were co-designed include the reference system, with wheat and barley in rotation, as well as three diversified systems that were also proposed and co-evaluated: the rotation of wheat, oil seed rape, and barley (DIV1); the rotation of wheat, pea, and barley (DIV2); and the rotation of wheat, intercrops of barley-common vetch, and barley (DIV3). The best system that was selected from the different stakeholders was the DIV3, as it had the highest evaluation of the stakeholders using agronomic, environmental, and socio-economic criteria. Full article

Crop diversification has been proposed as a promising strategy for transitioning towards sustainable agricultural systems. The Hetao Irrigation District faces multiple challenges in ensuring food security and farmer livelihood. A diversified green manure inclusive cropping system was designed to evaluate the influences of hairy vetch (Vicia villosa Roth) incorporation on soil nutrients, yield, and economic benefit compared to the existing wheat–maize–sunflower rotation system in the Hetao Irrigation District. The specific method was as follows: spring wheat (Triticum-durum L.)–vetch rotation in the first year, maize (Zea mays L.)/vetch intercropping in the second year, and sunflower (Helianthus annuus L.)/vetch relay intercropping in the third year. Over a 6-year experimental observation, green manure incorporation significantly increased soil alkaline hydrolyzed nitrogen and exchangeable potassium levels. Although the effect of green manure incorporation on the yield of rotated spring wheat and intercropped maize was not prominent, it improved sunflower yield in the second rotation cycle by 11%. Consequently, only the sunflower led to an increase in income of 235 CNY ha⁻¹ in the second rotation cycle. This indicates that the soil-property-building and yield-enhancing effects of green manure incorporation require time to accumulate. However, the benefits derived from increased yield were not sufficient to offset the production costs associated with green manure cultivation, resulting in less-than-desirable economic returns. Full article

Cover crops (CC) have great potential to enhance the sustainability of agroecosystems. However, the wide range of possible rotations of CC and cash crops (CaC) means that important knowledge gaps persist on how CC affects CaC. We investigated the legacy effects of five common CC (three monocultures: vetch, melilotus, and barley, and two mixtures: barley-vetch and barley-melilotus) on two of the most important CaC, maize and wheat. A microcosm, semi-controlled experiment was established simulating warm, low-income Mediterranean conditions. After two cycles, soil physicochemical and microbial properties, as well as plant growth and nutrition variables, were measured at the CC early growth CaC stage. In maize, barley CC had the best soil microbial and nutritional legacy effects, which resulted in the highest biomass and nutrient status. In contrast, barley produced the worst results on wheat, showing the disadvantages of growing two crops from the same tribe consecutively. CC mixtures also did not offer a productive advantage over pure CC. Additionally, our findings suggest that archaea seem to play a role in increasing N and Zn content in maize shoots. Furthermore, shoot B contents showed highly significant regressions with the CaC biomass. These results can help select the appropriate CC in each case. Full article

Legumes provide important benefits in rotations. Interseeding cover crops (CCs) allows an additional legume CC in case of a short window after the main crop. However, legume input level and management could modify the expected benefits. In a Mediterranean irrigated agroecosystem, we evaluated the responses of topsoil (0–10 cm) and early maize development to increasing legume CC input in a biannual maize–wheat rotation under traditional tillage (TT; CC incorporated) and minimum tillage (MT; CC rolled-crimped). In the third year, at two early maize stages, we tested three legume input levels: (i) R0, non-CC; (ii) R1, barley–vetch CC; (iii) R2, vetch interseeded into maize in addition to the CC mixture. Overall, MT enhanced soil properties, but frequently conditioned to legume input level. The tillage system affected R1 the most, with MTR1 showing the better overall soil response while TTR0 showed the poorest. MTR2 was the best combination for early maize development, but not for soil health. Moreover, a better overall soil health did not lead to a better early maize performance in the short term. In this alkaline soil, CC favored early maize growth, whereas mycorrhization, enhanced under TT, favored crop nutrition. Increased legume input under MT should be monitored to avoid negative effects in soil in the mid–long term. Full article

Observations of the effects of long-term paddy-upland rotations on soil carbon (C) and nitrogen (N) stocks are scarce. This experiment aimed to examine soil C and N stock characteristics and their relationships with rice yield using four long-term rotation systems. The results showed that in the topsoil at 50 cm, compared to rice-fallow (RF), rice-potato with rice straw mulch and return (RP) and rice-Chinese milk vetch (RC) increased soil organic carbon (SOC) stock by 19.67% and 15.29%, total nitrogen (TN) stock by 20.40% and 18.54%, and available nitrogen (AN) density by 61.54% and 34.44%, respectively; while rice-wheat (RW) increased AN density by 30.24%. Furthermore, the increases in densities of soil C and N at 20–30 cm were likely to increase rice above biomass and yield. The highest soil C and N densities were observed in RP, which was the best choice for increasing soil nutrients and rice yield. In addition, SOC, TN, and AN had obvious stratification and surface aggregation characteristics, and more than 70% of the total stocks were concentrated at the top 30 cm. These results provide a theoretical basis for the high-yield cultivation of rice in the middle and lower reaches of the Yangtze River. Full article

To investigate responses of two winter wheat genotypes under different crop management systems (rotation and tillage), a split–split plot experiment was conducted based on a randomized complete block design (RCBD) with three replications during 4 years in Maragheh, Iran. Three crop rotation treatments [vetch–wheat (V–W), chickpea–wheat (C–W), and safflower–wheat (S–W)] were considered in main plots, three tillage treatments (conventional-tillage (CT), minimum-tillage (MT), and no-tillage (NT)) were located in subplots, and two winter dryland wheat genotypes (Baran and Azar2) were allocated in sub-sub plots. Results indicated that soil moisture content in NT was greater than that in MT and CT. The highest relative water content (RWC), normalized difference vegetative index (NDVI), stomatal conductance (gs), and transpiration rate (E) were obtained from the Baran genotype in the V–W rotation under NT. In the last year of the experiment, rainfall productivity in NT treatment improved by 32%, compared to CT. The Baran genotype had higher rainfall productivity in both MT and NT treatments with 0.71 and 0.70 kg m⁻³, respectively. Crop water requirement was not affected by crop rotation or tillage treatments. Maximum grain yields in V–W, C–W, and S–W rotations were recorded as 2231, 2105, and 1991 kg ha⁻¹, respectively. With increasing soil moisture storage and improving rainfall productivity under full implementation of conservation agriculture components (after 4 years), grain yield of Baran and Azar2 improved in NT compared to that of CT by about 6–9% and 6–14%, respectively. Therefore, the application of V–W rotation with NT in cold dryland areas is recommended for developing of conservation agriculture system. Full article

Crop rotation is one of the oldest and most effective methods of restoring soil fertility, which declines when the same plant is grown repeatedly. One of the reasons for a reduction in fertility is the accumulation of pathogenic and unfavorable microbiota. The modern crop rotation schemes (a set of plant species and their order in the crop rotation) are highly effective but are designed without considering soil microbiota dynamics. The main goal of this study was to perform a short-term experiment with multiple plant combinations to access the microbiological effects of crop rotation. It could be useful for the design of long-term crop rotation schemes that take the microbiological effects of the crop rotation into account. For the analysis, five plants (legumes: vetch, clover, and cereals: oats, wheat, and barley) were used. These five plants were separately grown in pots with soil. After the first phase of vegetation, the plants were removed from the soil and a new crop was planted. Soil samples from all 25 possible combinations of primary and secondary crops were investigated using v4-16S rDNA gene sequencing. It was shown that the short-term experiments (up to 40 days of growing) are effective enough to find microbial shifts in bulk soil from different plants. Both primary and secondary cultures are significant factors for the microbial composition of microbial soil communities. Changes are the most significant in the microbial communities of vetch soils, especially in the case of vetch monoculture. Growing clover also leads to changes in microbiota, especially according to beta-diversity. Data obtained can be used to develop new crop rotation schemes that take into account the microbiological effects of various crops. Full article

Integrating cover cropping into crop–fallow rotation has been considered a key component of ecological intensification that could mitigate negative productivity and sustainability challenges associated with conventional fallow practices. However, the adoption of cover crops in water-limited environments has been limited by potential soil water and nitrogen (N) costs and resulting yield penalties. We examined the impacts of diverse cover crops on fallow soil water and mineral N dynamics and the legacy impacts on subsequent cash crop productivity and profitability. The cover crops used (forage oat—Avena sativa L. [grass], common vetch—Vicia sativa subsp. sativa L.)/fababean—Vicia faba L. [legume], forage rape—Brassica napus L. [brassica]) differed in functional traits related to growth, phenology, and soil water and N acquisition and use strategies. We found that grass-associated cover crops generally supported higher cash crop grain yield and profit than brassica- or legume-associated cover crops, mainly due to moderate biomass accumulation and water use and persistent groundcover. Cash crop grain yields increased by +19% and +23% following forage oat cover crop, with concomitant gains in gross margins of +96$ ha⁻¹ and +318$ ha⁻¹ for maize and winter wheat compared to conventional fallow. In contrast, maize grain yield following brassica-associated cover crops ranged from +8 to −21% and reduced gross margins by −229 to −686$ ha⁻¹ relative to conventional fallow. Legume- and brassica-associated cover crops had the lowest mungbean and winter wheat grain yield and gross margins compared to conventional fallow and the added stubble. Cash crop yields were related to cover crop biomass production, biomass N accumulation, residue carbon to N ratio, and legacy impacts through effects on soil water availability at cash crop sowing. Given the additional grain yield and gross margin benefits following grass-associated cover crops, they may provide a potential alternative fallow soil water and N management option that could improve crop productivity and cropping system resilience in water-limited environments. Full article

In this study, our investigated hypothesis was that different pre-crops would have different effects on earthworm activity and soil CO₂ emissions. We also hypothesized that a pre-crop clover–timothy mixture would perform best in terms of increasing the share of organic carbon in soil and, in this way, contribute to improving the sustainability of agroecosystems. The aim of this study was to explore the residual effects of using a 50-year-term of three different crop rotations and a continuous bare fallow period on soil CO₂ emissions by investigating the soil earthworm populations, soil agrochemical properties, and winter wheat yields. A field experiment was carried out from 2016 to 2017 at Vytautas Magnus University in Lithuania (54°53′ N, 23°50′ E). The experiment was conducted in crop stands of winter wheat cv. ‘Skagen’, which were sown in three crop rotations with different pre-crops and a continuous bare fallow period. The pre-crop used for winter wheat in the cereal crop rotation (CE) was a vetch and oat mixture for green forage, LEG-CER; the pre-crop used for winter wheat in the field with row crops (FWR) crop rotation was black fallow, FAL-CER; the pre-crop used for winter wheat in the Norfolk (NOR) crop rotation was a clover–timothy mixture, GRS-CER; and finally, continuous bare fallow, FAL-CONTROL, was used as well. The highest soil CO₂ emission intensity was determined after the pre-crops that left a large amount of plant residues (clover and timothy mixture) in the soil. Plant residues remaining after the pre-crop had the greatest effect on the number of earthworms in the soil after the harvesting of winter wheat. Winter wheat had the best yield when grown in grass and legume sequences. Crop rotation sequences that included perennial grasses accumulated higher contents of total nitrogen and organic carbon. The best values for the productivity indicators of wheat were obtained when it was grown after a fallow crop fertilized with cattle manure. An appropriate crop rotation that promotes the steady long-term contribution of organic matter and increases the content of organic carbon in the soil will have a positive effect on the agrochemical, biological, and physical properties of soil and agroecosystem sustainability; moreover, these effects cannot be achieved by technological means alone. Full article

The use of nitrogen fertilizers in agriculture is currently under high pressure to reduce its environmental impact and improve its currently low efficiency. Nitrification inhibitors and/or intercrops emerged in recent decades as useful tools to combat these problems. The objective of the experiment is to study the effect of these techniques on the yield, the nitrogen use efficiency (NUE) and N leaching in a maize–wheat rotation. Six treatments were studied, combining the use of ammonium nitrate sulfate (ASN) alone or with a nitrification inhibitor (DMPSA or 3,4-dimethylpyrazole succinic acid) and the use or absence of vetch (Vicia sativa L.) as an intercrop. The results showed that fertilized treatments did not show significant differences in crop development, but the use of DMPSA delayed the nitrate (NO₃⁻) availability and reduced N leaching losses (average N leaching reductions around 25% after maize harvest). On the other hand, the use of vetch as an intercrop helped to reduce the negative effects of N deficiency and, at the same time, increased the concentration of N in the soil during the following crop harvest (4.5 kg N ha⁻¹ on average after wheat harvest) and reduced losses due to leaching (average N leaching reductions around 14% after the maize–wheat season). The combination of both techniques (DMPSA and vetch intercrop) at the same time presented a synergic effect and greatly improved the environmental impact of the irrigated maize–wheat system. Full article

Cover crops can improve soil health by maintaining soil organic carbon (SOC) and nitrogen (N) contents, yet their dynamics in relation to crop yield in a semi-arid cropping system are poorly understood. The main objective of this study was to evaluate the response of diverse winter cover crop species and their mixture on SOC and N fractions and their relationship with sorghum (Sorghum bicolor L. Moench) yield in a winter wheat (Triticum aestivum L.)–sorghum–fallow rotation with limited irrigation management. Cover cropping treatments included pea (Pisum sativum L.), oat (Avena sativa L.), canola (Brassica napus L.), and mixtures of pea+oat (POM), pea+canola (PCM), peat+oat+canola (POCM), and a six-species mixture (SSM) of pea+oat+canola+hairy vetch (Vicia villosa Roth)+forage radish (Raphanussativus L.)+barley (Hordeum vulgare L.) as cover crops and a fallow. Soil samples were analyzed for residual inorganic N, potentially mineralizable carbon (PMC) and nitrogen (PMN), SOC, and total N. Response of labile inorganic N, PMC, and PMN varied with cover crop treatments. The SOC and total N contents did not differ among treatments but were 20% and 35% higher in 2020 than in 2019, respectively. Sorghum grain yield was 25% and 40% greater with oats than with PCM and canola cover crops in 2019, while it was 33–97% greater with fallow and oats than other treatments in 2020. Oat as a cover crop could improve the resilience of limited-irrigation cropping systems by increasing SOC, soil N, and crop yield in semi-arid regions. Full article