Alternative Cropping Systems Research Articles

Unveiling the Bounty: A Systematic Synthesis of Biodiversity and Ecosystem Services in Mediterranean Lentil and Chickpea Cultivation Through Alternative Pulse Systems

ABSTRACTPulses get increasing awareness not only for their nutritional value but also for their multifunctionality in sustainable agri‐food systems. Although having a long tradition in Mediterranean regions, their share of arable land is very low. Knowledge about pulse cropping, considering nonmarket outputs in alternative cropping systems, is scarce. To this end, we conducted a systematic literature research. We synthesized the current quantified state of knowledge about associated biodiversity in pulse systems and ecosystem services, specifically food/feed provision and soil quality, in lentil and chickpea cropping systems using alternative management practices in the Mediterranean and analysed their impact compared to conventional practices employing a meta‐analysis. As alternative practices, we considered practices frequently proposed to be sustainable and more ecologically oriented than conventional cropping. Most studies examined soil quality, especially chemical quality, followed by grain yield. Very few studies surveyed biodiversity, most of which used arable flora as an indicator. Mean lentil and chickpea grain yields were 1484.4 ± 665 kg/ha under alternative practices, and flora richness was on average 10.9 ± 4 species during the pulse phase. We found significant positive impacts of organic farming on biodiversity, no tillage on soil quality and diversified rotations on yield. In multiservice trials, no tillage tended to be synergistic for both, yield and soil quality. In conclusion, organic and conservation agriculture elements seem promising techniques for ecosystem service‐enhancing pulse management. Anyhow, the current evidence base on ecosystem service performance in alternative pulse systems is empirically not yet robust to conclude sound data‐driven management recommendations—especially with a focus on biodiversity. However, we can draw justified hypotheses that can focus future research and can be tested in the field.

Finding synergies between agroecology and industrial ecology toward sustainable agricultural systems

The question of how humans will co-create better food and agricultural systems is ex­tremely complex, and responses vary significantly due to experiences, worldviews, and values. Those of us working on this question typically agree that the goal is to realize systems that are equitable, just, minimize harm to, and ultimately support healthy ecosystems for current and future generations. I will refer to this goal as sustainability. My training is in industrial ecology and civil and environmental engineering, and my professional research focuses on questions of the climate and nutrient impacts associated with agriculture and food products as they are in our time, i.e., dominated by commodity crops. I was introduced to agroecology about 15 years ago while looking into ways to reduce nutri­ent runoff and improve soil and ecosystems, such as alternative cropping systems, integrated farming practices, permaculture, and more. Eventually, I learned of agroecology as a science, movement, and practice, which increased my interest to learn more. Both industrial ecology and agroecology, and the many branches within them, earnestly pursue facets of sustainability in agriculture, food, and other bio-based systems, and collaboration could lead to synergistic efforts. . . .

UAV time-series imagery show diversity treatment effects on cabbage growth

The demand for more sustainable farming is driving interest in alternative cropping systems, such as strip intercropping. In such systems, two or more crops are grown simultaneously on the same field, offering advantages such as increased biocontrol of weed, pest, diseases, and increasing productivity in resource-limited ecosystems. However, with strip intercropping, complexity increases and quantitative data to study the competition between plants are still limited due to the current manual process of acquiring data. While individual-plant data would facilitate this study, the manual acquisition is not feasible for large-scale experiments. Alternatively, unmanned aerial vehicles (UAV) equipped with high-resolution camera can cover large areas and estimate individual-plant growth from RGB imagery using automated image-processing methods. This study investigated its applicability to monitor the plant-height development of individual cabbage plants in space and time with sufficient accuracy and to identify the potential differences between strip intercropping treatments. Using RGB imagery and structure-from-motion analysis, a digital surface model (DSM) was created. Individual plant-height was calculated from the DSM by estimating the height of the vegetation and the height of the soil. Comparing the height estimations with ground-truth height measurements showed an overall root mean square error (RMSE) of 4.67 cm, which is in the same range as the 4 cm standard deviation between measurements of multiple observers. The UAV-based height estimation of individual plants was used not only to compare the development in a strip intercropping field to that in a monoculture but also to compare with various treatments in the strip intercropping system. The results show that the plants grew faster in intercropping conditions than in monocropping conditions, with a subtle difference between treatments. Our results illustrate that with a UAV-based imaging approach we can go beyond current experimental practice and collect vast amounts of data on individual plants with high spatial and temporal resolution with an accuracy similar to that of manual measurements.

Policy measures effectively reduce soil nitrous oxide emissions with minor trade‐offs in crop yield

AbstractNitrous oxide (N2O) emissions are closely linked to agricultural fertilisation. European and national policy incentives have been set to reduce greenhouse gas (GHG) emissions; however, only a few evaluations have been conducted. Avoiding such emissions is an important climate change mitigation measure, but it is still uncertain which management measures over a long‐term, best out‐balance crop yield and GHG balances in agricultural systems. We here used the process‐based LandscapeDNDC model to simulate N2O emissions and trade‐offs in yield and soil nitrogen budget for four alternative arable cropping systems in three Austrian agricultural production zones belonging to different climatic regions. We evaluated statistical data on crop rotations and management practices, predominant soil types, and 10‐year daily weather conditions for four cropping systems: (1) conventional farming receiving the maximum allowed nitrogen fertilisation rate (Nmax), (2) conventional farming receiving 15% less fertiliser, (3) conventional farming receiving 25% less fertiliser, and (4) organic farming. Our results showed that soil N2O emissions could be best reduced in wet, high‐yield regions. Reducing nitrogen fertilisation by 15% and 25% mitigated N2O emissions by, on average, 22% and 39%, respectively, while the yield was reduced by 5% and 9%, respectively. In comparison, the same crops grown in the organic cropping system released 60% less N2O, but yield declined on average by 23%. Corn, winter barley, and vegetables showed the highest N2O reduction potential under reduced fertiliser input in conventional farming. In addition to N2O emissions, reduced fertilisation substantially decreased other nitrogen losses into the water and atmosphere. Generally, the soils under all cropping systems maintained a positive mean nitrogen budget. Our results suggest a significant emission reduction potential in certain production zones which, however, were accompanied by yield reductions. Knowledge of the emission patterns from cropping systems under different environmental conditions is essential to set the appropriate measures. In addition, region‐specific measures to reduce soil N2O emissions have to be in line with farmers' interests in order to facilitate the successful implementation of targeted nitrogen management.

Liberica coffee as an alternative cropping system for sustainable farming on Indonesian Peatlands

Liberica coffee as an alternative cropping system for sustainable farming on Indonesian Peatlands

Production potential of pulse-and oilseed-based climate-resilient alternative cropping systems for diversification of rice (Oryza sativa)–wheat (Triticum aestivum) in North-western Indo-Gangetic Plains

A field experiment was conducted during 2016–17, 2017–18 and 2018–19 at the Punjab Agrcultural University, Ludhiana, India, to evaluate the economic feasibility of pulse-and oilseed-based new alternative cropping systems in comparison to rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system. Among the 10 cropping systems evaluated in a randomized block design on a loamy sand soil, the highest rice-equivalent yield (23.2 t/ha) was obtained in groundnut (Arachis hypogaea L.)–garden peas (Pisum sativum L.)–sunflower (Helianthus annuus L.) with highest sustainable- yield index (0.81), followed by groundnut –garden peas– spring maize (Zea mays L.) (22.5 t/ha) as significantly better than rest of the cropping systems. In comparison to conventional rice–wheat system, higher net returns as well as relative economic efficiency were recorded in 4 cropping systems, viz. groundnut–garden peas–sunflower, groundnut–garden peas–spring maize, rice–wheat–summer mungbean [Vigna radiata (L.) R. Wilczek] and mungbean–toria [Brassica rapa subsp. dichotoma (Roxb.) Hanelt]–sunflower. Maximum apparent water productivity was observed in pigeonpea [Cajanus cajan (L.) Millsp.]–chickpea (Cicer arietinum L.)– summer mungbean, whereas the maximum nutrient-use productivity was observed in groundnut–garden peas– sunflower, followed by pigeonpea–chickpea–summer mungbean and the least values were recorded in rice–wheat system. Thus, resource-conserving biointensive cropping systems, viz. groundnut–garden peas–sunflower, groundnut–garden peas–spring maize, rice–wheat–summer mungbean and mungbean–toria–sunflower can be adopted for higher productivity, profitability and sustainability.

Multicriteria assessment of alternative cropping systems at farm level. A case with maize on family farms of South East Asia

CONTEXTIntegration of farms into markets with adoption of maize as a cash crop can significantly increase income of farms of the developing world. However, in some cases, the income generated may still be very low and maize production may also have strong negative environmental and social impacts. OBJECTIVEMaize production in northern Laos is taken as a case to study how far can farms' performance be improved with improved crop management of maize with the following changes at field level: good timing and optimal soil preparation and sowing, allowing optimal crop establishment and low weed infestation. METHODSWe compared different farm types' performance on locally relevant criteria and indicators embodying the three pillars of sustainability (environmental, economic and social). An integrated assessment approach was combined with direct measurement of indicators in farmers' fields to assess eleven criteria of local farm sustainability. A bio-economic farm model was used for scenario assessment in which changes in crop management and the economic environment of farms were compared to present situation. The farm model was based on mathematical programming maximizing income under constraints related to i) household composition, initial cash and rice stocks and land type, and ii) seasonal balances of cash, labour and food. The crop management scenarios were built based on a diagnosis of the causes of variations in the agronomic and environmental performances of cropping systems, carried out in farmers' fields. RESULTS AND CONCLUSIONSOur study showed that moderate changes in crop management on maize would improve substantially farm performance on 4 to 6 criteria out of the 11 assessed, depending on farm types. The improved crop management of maize had a high economic attractiveness for every farm type simulated (low, medium and high resource endowed farms) even at simulated production costs more than doubling current costs of farmers' practices. However, while an improvement of the systems performance was attained in terms of agricultural productivity, income generation, work and ease of work, herbicide leaching, improved soil quality and nitrogen balance, trade-offs were identified with other indicators such as erosion control and cash outflow needed at the beginning of the cropping season. SIGNIFICANCEUsing farm modelling for multicriteria assessment of current and improved maize cropping systems for contrasted farm types helped capture main opportunities and constraints on local farm sustainability, and assess the trade-offs that new options at field level may generate at farm level.

Contrasting effects of bioenergy crops on biodiversity.

Agriculture is driving biodiversity loss, and future bioenergy cropping systems have the potential to ameliorate or exacerbate these effects. Using a long-term experimental array of 10 bioenergy cropping systems, we quantified diversity of plants, invertebrates, vertebrates, and microbes in each crop. For many taxonomic groups, alternative annual cropping systems provided no biodiversity benefits when compared to corn (the business-as-usual bioenergy crop in the United States), and simple perennial grass-based systems provided only modest gains. In contrast, for most animal groups, richness in plant-diverse perennial systems was much higher than in annual crops or simple perennial systems. Microbial richness patterns were more eclectic, although some groups responded positively to plant diversity. Future agricultural landscapes incorporating plant-diverse perennial bioenergy cropping systems could be of high conservation value. However, increased use of annual crops will continue to have negative effects, and simple perennial grass systems may provide little improvement over annual crops.

Soil Greenhouse Gas Emissions in Intercropped Systems Between Melon and Cowpea

There is a need to assess alternative cropping systems for climate change mitigation. Hence, we aimed to evaluate if cowpea, a legume crop with high climate adaptability and active rhizodeposition, can reduce GHG emissions when intercropped with melon, if different intercropping patterns can affect these soil GHG emissions, and elucidate if GHG emissions are related by soil and crop properties. We compared a cowpea and melon monocultures with different melon-cowpea intercropping patterns during two crop cycles. The different melon-cowpea intercropping patterns were: row intercropping 1:1 (melon:cowpea), row intercropping 2:1 (melon:cowpea) and mixed intercropping (alternate melon/cowpea plants within the same row), receiving 30% less fertilizers than monocrops. Results showed that CO2 emission rates were higher in the row 2:1 and row 1:1 intercropping systems compared to mixed intercropping, melon monocrop and cowpea monocrop, with the lowest emissions, likely due to the highest density of both plant species, which may stimulate microbial communities. Soil N2O emission rates were not affected by crop diversification, with very low values. Soil CO2 and N2O emissions were not correlated with environmental factors, soil properties or crop yield and quality, suggesting that crop management and plant density and growth were the main factors controlling GHG emissions. When the GHG emissions were expressed on a crop production basis, the lowest values were observed in mixed intercropping, owing to higher crop production. However, the 1:1 and 2:1 cowpea intercropping systems, with the lowest overall crop production, showed higher values of GHG emissions per unit of product, compared to cowpea monocrop. Thus, intercropping systems, and mostly mixed intercropping, have the potential to contribute to sustainable agriculture by increasing land productivity, reducing the need for synthetic fertilizers and decreasing GHG emissions per unit of product. These results highlight the importance of considering both agricultural productivity and greenhouse gas emissions when designing and implementing intercropping systems.

Collembola taxonomic and functional diversity in conventional, organic and conservation cropping systems

Intensive agriculture has been demonstrated to be a main threat to soil biodiversity through physical and chemical disturbances of soil. Alternative systems based on lower disturbances may help to promote soil biodiversity and its role in soil functioning. However, the effects of alternative systems on soil biodiversity are still poorly understood, especially regarding soil mesofauna. In this study, we aimed to assess the effects of alternative cropping systems and practice intensity on the taxonomic and functional diversity of Collembola. Collembola were sampled for two consecutive years in 21 fields (3 plots per field) under conventional or alternative systems, namely conservation or organic systems either stable (≥7 years) or in transition (≤3 years). Indicators and indices were computed to characterize separately tillage, pesticide treatments and organic fertilization in each field. Collembola species and functional traits were investigated. Functional diversity of Collembola was assessed using species traits (i.e. traits from the literature) and by conducting length measurements directly on collected Collembola individuals (body, head, leg, antenna and furca length). Collembola diversity was highly variable between and within cropping systems and years. Species richness was notably higher in conservation than in conventional systems in the second year of the study. More specifically, low tillage and high pesticide treatment intensities increased taxonomic and functional diversity and affected species with traits adapted to the surface (i.e. scales, trichobothria). Measured Collembola body length additionally revealed the presence of larger individuals under low tillage and high pesticide treatment intensities, with similar results for other length traits. Overall, our results revealed that 1) taxonomic and functional diversity are complementary to understand the effects of agricultural practices and systems on Collembola and 2) measurement of body length is relevant to assess the effects of disturbances on the local Collembola community.

Evapotranspiration partitioning and agricultural drought quantification with an optical trapezoidal framework

The Optical Trapezoidal method is a recently proposed method using solely optical remote sensing data with promising potential in hydroclimatic applications; however, its application in evapotranspiration (ET) partitioning is still questionable. This study therefore improved an Optical Trapezoidal-based Evaporative Fraction (OPTREF) model reliant on the physical association between soil surface properties and shortwave infrared transformed reflectance (STR). The proposed model was parameterized using trapezoidal shapes formed by STR and Normalized Difference Vegetation Index (NDVI) retrieved from Sentinel-2 to compute contribution of transpiration to ET (T/ET) in the Central Valley region of California, United States. Results indicated that the OPTREF model efficiently captured regional plant characteristics and seasonal variation of T/ET for three typical land cover types in study region (cropland, grassland, and savanna), particularly T/ET discrepancies rising from alternative cropping systems in cropland. Importantly, predicted T/ET values were in good agreement with previous modelling and empirical reports; for example, T/ET ranges in [0.37-0.75] for cropland, [0.30-0.82] for grassland, and [0.39-0.77] for savanna. In addition, applicability of the OPTREF approach was investigated in tracking agricultural drought using evaporative drought index (EDI), together with analysis of physiological response of T/ET to drought. The OPTREF-based EDI consistently reflected the same drought patterns indicated by records of vegetation health index and drought area percentages data from NOAA. Also, our findings uncovered that under extreme drought, the T/ET ratio is likely to increase and might be approximately equal to 1.0 in areas covered by drought-tolerant plants. Overall, this OPTREF approach offers novelty, simplicity, and versatility to satellite-based remote sensing of ET partitioning and identifying agricultural drought, especially in the context of rapid climate variation.

Relay cropping as an adaptive strategy to cope with climate change

AbstractClimate change and its complex interactions with crops and cropping systems present challenges to agricultural production. Resilient systems that provide food security for a burgeoning population, built by improving crops and developing new alternative cropping systems, are needed to cope with the myriad impacts climate change has on agriculture. Relay cropping is a systems strategy to sustainably intensify crop production and provide environmental benefits. Relay cropping involves interseeding one plant species into an established crop, creating a temporary spatial‐temporal overlap of the two crops. This system keeps living plant cover on the agricultural landscape most of the year, which has implications for adapting to and even mitigating climate change impacts. As global warming progresses, land area suitable for relay cropping or producing more than one crop per year will likely expand to more northerly latitudes. The following review specifically focuses on relay cropping, giving examples of how it can potentially improve agricultural system resilience and adaptability to climate change and reduce greenhouse gas emissions, while also addressing potential limitations. More research is needed to improve crop genetics, crop combinations, and management practices best suited for relay cropping to further develop systems that can adapt to changing weed and insect dynamics as well as improve nitrogen and water use under current and future predictions of climate change.

Alternative Cropping Systems for Climate Change

Climate change and increased climate variability are significant contemporary issues and create new challenges for agriculture and the whole food production chain [...]

Weed control in a pesticide‐free farming system with mineral fertilisers

AbstractNegative impacts of pesticides on the environment and human health, the risk of pesticide residues in the food chain, and the problems with herbicide‐resistant weed biotypes support the need for alternative cropping systems. The objective of this study was to investigate weed populations, weed management and crop yield in a pesticide‐free cropping system with the use of mineral fertilisers. Conventional‐, organic‐ and mineral‐ecological cropping systems (MECS) with 6‐year crop rotations including winter wheat, maize, winter triticale or winter rye, soyabean or spring pea, and spring barley were established in a randomised complete strip plot design with four repetitions. Experiments were conducted at four locations in Germany. Preventive and sensor‐guided mechanical weed management strategies were applied in all crops in the organic system and in MECS. Herbicide were applied in the conventional farming system. Weed densities, weed species composition, weed control efficacy (WCE) and crop yield were analysed over 2 years in 2020 and 2021. Conventional farming had the highest WCE and 1–7 weeds m−2 (2.7% weed coverage) after herbicide application. In the organic cropping system and MECS, up to 27 weeds m−2 were counted after camera‐guided weed hoeing. Weed coverage in MECS (9.7%) was higher than in the organic cropping system with 7.7%. Crop yield in MECS was equal to the conventional farming system and 20% higher yield than in the organic farming system. MECS represents a promising new and productive cropping practice if an effective integrated weed management strategy is applied.

Challenges and technological interventions in rice-wheat system for resilient food-water-energy-environment nexus in North-western Indo-Gangetic Plains: A review.

Rice (Oryza sativa L.)-wheat (Triticum aestivum L.) cropping system in north-western Indo-Gangetic Plains performed a crucial role in the national food security. However, thewidespread andintensive cultivation of this systemhas led to serious problems such asdeclining groundwater table (~1meteryear-1) with sharp increase in number of districts under over-exploitation category, residue burning, higher greenhouse gases emission and herbicide resistance in weeds, causing stagnant crop productivity and lesser profitability. In this review article, an attempt has been made to discuss the major issues pertaining to intensive rice-wheat cultivation amidst climate vagaries and futuristic approach to address these challenges. Different tillage- and crop-specific recommendations such as adoption of direct seeded rice, diversification with lesser resource guzzling crops such as maize (Zea mays L.) at least on the periodic manner especially in light-medium soils, inclusion of summer legumes and alternative tillage systems (permanent beds and zero tillage with residue retention) have been suggested to address these issues. However, crop performance under these techniques has been found to belocation, soil and cultivar specific. The absence of aerobic tailored genotypes and weeds have been identified as the major constraints in adoption of direct seeded rice. The integrated strategies of conservation tillage, crop breeding program and resource conserving region- and soil-specific agronomic measures with crop diversification would be helpful in tackling the sustainability issues. It requires future efforts on developing crop genotypes suited to conservation tillage, effective weed control strategies and trainings and demonstrations to farmers to switch from conventional rice-wheat system to alternative cropping systems.

Comparing water related indicators and comprehensively evaluating cropping systems and irrigation strategies in the North China Plain for sustainable production

The fully irrigated winter wheat–summer maize double cropping system (DWM) has caused groundwater overexploitation and aggravated water scarcity in the North China Plain (NCP). Therefore, it is necessary to select alternative cropping systems with effective irrigation strategies to maintain the sustainable use of groundwater and maintain crop productivity. However, the evaluation indicators, especially the water-related indicators of cropping systems and irrigation strategies in current studies are not consistent and it is difficult to obtain a comprehensive evaluation result. Hence, to overcome these challenges, this study reviewed and compared groundwater indicators, water use indicators, water production performance indicators and output indicators, and summarized twelve evaluation combinations. Four evaluation combinations with grain yield as output indicator were selected to comprehensively evaluate the cropping systems and irrigation strategies developed by Agricultural Production Systems sIMulator (APSIM) at a typical site in the NCP in the past 52 years. The indicator weights were determined by analytic hierarchy process, entropy weight method, random forest algorithm and principal component analysis. Evaluation results showed that when the main goal was to guarantee food safety or improve the beneficial water use, the DWM was selected as the best choice and the WMM (winter wheat–summer maize → spring maize system, three crops in two years) was the alternative cropping system. Under this condition, water saving irrigation should be vigorously developed to reduce groundwater exploitation. When the four indicator types had the same weight, the DWM under rainfed was the best choice to improve evapotranspiration use efficiency and precipitation use efficiency; the monocropping spring maize system under normal irrigation strategy was the best choice to reduce water footprint. The WMM under rainfed was the alternative choice to improve evapotranspiration use efficiency, improve precipitation use efficiency and reduce water footprint. The evaluation methods proposed in this study could be used as reference in the comparison of cropping systems and irrigation strategies in other water-related situations.

Improvement of Water and Nitrogen Use Efficiencies by Alternative Cropping Systems Based on a Model Approach.

The conventional double cropping system of winter wheat and summer maize (WW-SUM) in the North China Plain (NCP) consumes a large amount of water and chemical fertilizer, threatening the sustainable development of agriculture in this region. This study was based on a three-year field experiment of different cropping systems (2H1Y-two harvests in one year; 3H2Y-three harvests in two years; and 1H1Y-one harvest in one year). The 2H1Y system had three irrigation-fertilization practices (FP-farmer's practice; RI-reduced input; and WQ-Wuqiao pattern in Wuqiao County, Hebei Province). A soil-crop system model (WHCNS-soil water heat carbon nitrogen simulator) was used to quantify the effects of different cropping systems on water and nitrogen use efficiencies (WUE and NUE, respectively), and to explore the trade-offs between crop yields and environmental impacts. The results showed that annual yield, water consumption, and the WUE of 2H1Y were higher than those of the 3H2Y and 1H1Y systems. However, local precipitation during the period of crop growth could only meet 65%, 76%, and 91% of total water consumption for the 2H1Y, 3H2Y and 1H1Y systems, respectively. Nearly 65% of irrigation water (groundwater) was used in the period of wheat growth that contributed to almost 40% of the annual yield. Among the three patterns of the 2H1Y system, the order of the WUE was 2H1Y_RI > 2H1Y_WQ > 2H1Y_FP. Compared to 2H1Y_FP, the total fertilizer N application rates in 2H1Y_WQ, 2H1Y_RI, and 3H2Y were reduced by 25%, 65%, and 74%, respectively. The 3H2Y system had the highest NUE of 34.3 kg kg-1, 54% greater than the 2H1Y_FP system (22.2 kg kg-1). Moreover, the 3H2Y system obviously reduced nitrate leaching and gaseous N loss when compared with the other two systems. The order of total N loss of different cropping systems was 2H1Y (261 kg N ha-1) > 1H1Y (78 kg N ha-1) > 3H2Y (70 kg N ha-1). Considering the agronomic and environmental effects as well as economic benefits, the 3H2Y cropping system with optimal irrigation and fertilization would be a promising cropping system in the NCP that could achieve the balance between crop yield and the sustainable use of groundwater and N fertilizer.

Replacement of rice-wheat cropping system with alternative diversified systems concerning crop productivity and their impact on soil carbon and nutrient status in soil profile of north-west India

The depth-wise depletion of soil organic carbon (OC), macro, micro, and secondary nutrients under the rice-wheat system has resulted in multi-nutrient deficiencies and a decline in crop productivity, emphasizing the replacement of rice-wheat with alternate cropping systems like maize-wheat, cotton-wheat, soybean-wheat, and moongbean-wheat to restore soil fertility and productivity. Long-term investigations (since 2016) revealed that there was a depth-wise decline in pH, EC, OC, and nutrients in soil profile (Udic Ustrochept, Inceptisols) among different cropping systems. The practice of deep-rooted cropping systems (maize-wheat and cotton-wheat) led to maximum OC, soluble calcium, and magnesium, while legume-based systems (especially soybean-wheat) led to maximum available phosphorus (30.86 kg ha−1), boron (0.49 mg kg−1), and DTPA-zinc (1.82 mg kg−1) in soil profile (0–120 cm). This system also led to the maximum surface soil OC, available phosphorus, soluble magnesium, DTPA-zinc, and boron. From the production point of view, soybean-wheat system (115.65 q ha−1) led to higher system grain productivity as compared to rice-wheat system (109.60 q ha−1). Therefore, the practice of alternative cropping systems like soybean-wheat and cotton-wheat helps in the build-up of nutrient status by playing a pivotal role in influencing the surface and depth-wise distribution of organic carbon and nutrients in the soil.

Promoting oil palm-based agroforestry systems: an asset for the sustainability of the sector

Until recently, the massive development of industrial and smallholder oil palm (Elaeis guineensis Jacq.) plantations has generally been conducted according to the monocrop model. However, alternative cropping systems have emerged, based on more diversified systems that combine various crops within the oil palm plots. By giving this plant a status equivalent to that of a tree, these practices correspond to agroforestry systems. In the present study, 39 agroforestry systems were identified worldwide through a preliminary literature review, a review of NGO websites and expert surveys. Our results reveal five different types of oil palm agroforestry systems: (i) associations with livestock during the production phase of the oil palm; (ii) traditional African palm and food crop systems sustained over time; (iii) associations with food crops during the juvenile phase of the oil palm; (iv) systems developed by family farms that permanently associate other plants; and (v) prototype designs developed by research institutions, often at the request of local agricultural enterprises. The spatiotemporal description of these systems enabled us to identify associated ecosystem services. Building on various proposals of biodiversity insertion in a monoculture to convert it into an agroforestry system, the present study offers new perspectives for the sustainable development of palm oil production.

Labour demand – The forgotten input influencing the execution and adoptability of alternative cropping systems in Eastern Australia

CONTEXTUnderstanding the quantity and timing of labour to fulfill the goals of different cropping systems or crop rotations is critical, but poorly quantified and understood in many agricultural systems, including the grain-growing regions of eastern Australia. Yet, labour supply and demands are important considerations for farmers and can significantly influence their agronomic management and decisions to adopt modified crop rotation systems. OBJECTIVEHere, we investigated the extent to which crop rotation systems, that differed in their intensity (i.e. the proportion of time when crops were growing), and diversity (i.e. the range of crops grown) influence labour requirements and labour productivity. METHODSWe used the Agricultural Production Systems sIMulator (APSIM) to simulate a set of different crop rotations and combined the output with farmer survey data and expert knowledge derived from farm advisers to compute the labour inputs for key crop operations (i.e. sowing, spraying, harvesting). This information was used to calculate the labour required and the timing of this demand for each cropping system. RESULTS AND CONCLUSIONSWe showed that as the cropping intensity increases the labour demand also increases, and vice versa. However, only small differences in labour demands were identified between systems with differing crop diversity (i.e. range of crops grown). Thus, when it comes to labour demands, crop diversity is less critical than cropping intensity. Labour demand was highly seasonal, with peaks around the intense operations of sowing and harvesting. These peak demands constrained the area that could be managed by a unit of labour, particularly as the cropping intensity increased. Further, this analysis highlights that the most profitable systems may not necessarily be the most efficient in terms of labour productivity (i.e. return per unit of labour). This analysis shows that when labour is limiting, labour demands and especially peak periods may contribute to a farmer's choice of cropping systems, adding to other critical factors like risk aversion and profit maximisation. SIGNIFICANCEThe analysis contributes to the literature on the role of labour in the context of influencing the implementation and adoption of what are seemingly more productive or profitable farming systems. In particular, the results demonstrate how labour as a critical farm resource (i.e. its quantity, seasonality and timing, and productivity) can influence the design of crop rotations.