Conservation Agriculture Research Articles

Agronomic and Carbon Productivity of Corn (Zea Mays Linn.) and Corn-Legume Intercropping Under Conservation Agriculture Practice System (Caps)

Carbon productivity is important in plant life and corn is important for human consumption throughout the world. A study was conducted to determine the agronomic and carbon productivity of corn and corn legumes under the conservation agriculture practice system. Agriculture practice system using a Randomize Complete Block Design (RCBD) with three treatments and replicated four times. The objective of the study was to determine the agronomic characteristics of corn intercrop with soybean and cowpea; to determine the carbon productivity of corn and legumes, and to evaluate the total productivity of corn-legumes in intercropping. The result revealed that among the agronomic parameters plant height, harvest index, partitioning coefficient, and total biomass the statistical analysis showed significant differences among treatment means, while 50 % days to flower analysis of variance showed no significant differences among treatments. In the yield parameters including shelling, percentage had shown significant differences among treatments but yield showed no significant difference they are not comparable to each other. The carbon productivity including total dry matter yield t/ha and carbon productivity t/ha, based on the result on carbon productivity Treatment 3 corn intercropped with cowpea obtained a high amount of carbon with (1.63). Thus, it recommended that corn intercropped with cowpea is better to determine the level of carbon productivity under the conservation agriculture practice system.

Influence of conservation agriculture and agroforestry in maintaining sustainability in Madhya Pradesh, India

Influence of conservation agriculture and agroforestry in maintaining sustainability in Madhya Pradesh, India

Effects of Cover Crop and Filter Strips on Sediment and Nutrient Loads Measured at the Edge of a Commercial Cotton Field

Highlights Winter cover crops and growing season filter strips were implemented without sacrificing significant land and achieved positive results. Cover crops reduced runoff depth, peak flow rate, sediment, TP, and TN load by 30%, 49%, 43%, 4%, and 7%, respectively. Filter strips reduced runoff depth, peak flow rate, sediment, TP, and TN load by 36%, 49%, 56%, 15%, and 21%, respectively. Abstract. Effective use of conservation practices in agricultural fields can reduce sediment and other pollutant loads entering waterways. In this study, we evaluated the effectiveness of using cover crops and filter strips on sediment and nutrient loss at the edge of paired, 7.83 ha (19.35 ac), commercial cotton fields in the Lower Mississippi River Basin (LMRB) in northeastern Arkansas. Cover crops included winter wheat, black oat, and ryegrass seeded in the winter fallow period, while filter strips included a grassy turn row at the field border and switchgrass transplanted around the drainage pipe at the edge of the treatment field. The field border of the control field was generally free from vegetation. A monitoring system measured discharge and collected composite water samples from rainfall and irrigation runoff events. Water samples were analyzed for phosphate (PO4-P), total phosphorus (TP), nitrate (NO3-N), ammonium (NH4-N), total nitrogen (TN), and suspended sediment concentrations. Data were collected from 2015 to 2020. Baseline data were collected when both fields had similar conservation practices (i.e., no cover crops in 2015 and no filter strips in 2015 and 2016). A comparison of 66 common runoff events between the control and cover crop treatment fields during the non-growing season indicated that the median peak flow and sediment loads were significantly reduced (p < 0.05), with an average reduction of 49% and 43%, respectively. Similarly, a comparison of 55 common runoff events between the control and filter strips treatment fields during the growing season found that the filter strips reduced significantly with average runoff by 36%, peak flow by 49%, and sediment loads by 56% (p < 0.05). Nutrient load reductions by the cover crop and filter strip treatments were not significantly different than by the control (p > 0.05). However, mean PO4-P, TP, NO3-N, NO2-N, NH4-N, and TN loads in the cover crop treatment field were lower than in the control field by 21%, 4%, 9%, 4%, 17%, and 7%, respectively. Similarly, mean PO4-P, TP, NO3-N, NH4-N, and TN loads in the filter strip treatment field were lower than in the control field by 23%, 15%, 11%, 42%, and 21%, respectively. The results demonstrated runoff depth, peak flow rate, nutrients, and sediment load reductions following the implementation of cover crops and filter strips at the commercial field scale. Keywords: Agricultural conservation practices, BMPs, Cotton, Cover crop, Edge-of-field monitoring, Filter strips, Switch grass.

Effectiveness Overview of Agricultural Conservation Practices for Water Quality Improvement Part II

Highlights This article summarizes ten agricultural conservation practices reviewed in both editions of the collection. Mean sediment load was reduced 73%-80% by residue and tillage management, filter strips, and cover crops. Mean nitrate-N load reduction ranged from 34%-46% for filter strips and water management practices. Phosphorus loads and concentrations were reduced by most practices, but dissolved P increased with two practices. Cost effectiveness varied widely, and these results may help in efforts to prioritize conservation implementation. Abstract. Although significant governmental investment has been provided to implement agricultural conservation practices (ACPs) for water quality improvement, eutrophication and hypoxia persist in coastal and fresh waters. A better understanding of the comparative effectiveness of ACPs is needed to improve environmental outcomes with the funding available. The objectives of this overview article are to (1) compare the performance and cost effectiveness among all the ACPs reviewed in both the first and second editions of the Special Collection and (2) present critical perspectives for researchers, policymakers, and funding entities seeking to improve water quality. The ten ACPs reviewed encompassed a range of goals, strategies, and landscape placement and varied widely in performance for their reduction of sediment, nitrogen (N), and phosphorus (P) and their cost-effectiveness. Three ACPs included performance measures for all three constituents: sediment, N, and P, whereas others focused only on N (nine ACPs) and/or P (six ACPs). The four ACPs that are considered “water management” practices: drainage water management, denitrifying bioreactor, saturated buffer, and constructed wetland were all effective in mitigating the effects of nutrients in subsurface drainage water and showed average nitrate-N load reductions of 40%-46%. In contrast, few practices were found effective in reducing dissolved P (DP) loss from agricultural fields. Four ACPs (residue and tillage management, conservation crop rotation, drainage water management, and nutrient management) demonstrated possible net economic benefits, while perspectives were provided for prioritizing financial assistance for other ACPs. Monitoring recommendations developed during the literature reviews highlighted the need for more long-term field-scale monitoring to better reflect multi-year climatic variability. Keywords: Constructed wetland, Cost effectiveness, Cover crop, Crop rotation, Denitrifying bioreactor, Drainage water management, Filter strip, Monitoring, Nitrogen, Nutrient management, Performance effectiveness, Phosphorus, Residue and tillage management, Saturat

Efficient crop residue management under conservation agriculture for improving soil quality: A review

Efficient crop residue management under conservation agriculture for improving soil quality: A review

Net greenhouse gas balance in U.S. croplands: How can soils be part of the climate solution?

Agricultural soils play a dual role in regulating the Earth's climate by releasing or sequestering carbon dioxide (CO2 ) in soil organic carbon (SOC) and emitting non-CO2 greenhouse gases (GHGs) such as nitrous oxide (N2 O) and methane (CH4 ). To understand how agricultural soils can play a role in climate solutions requires a comprehensive assessment of net soil GHG balance (i.e., sum of SOC-sequestered CO2 and non-CO2 GHG emissions) and the underlying controls. Herein, we used a model-data integration approach to understand and quantify how natural and anthropogenic factors have affected the magnitude and spatiotemporal variations of the net soil GHG balance in U.S. croplands during 1960-2018. Specifically, we used the dynamic land ecosystem model for regional simulations and used field observations of SOC sequestration rates and N2 O and CH4 emissions to calibrate, validate, and corroborate model simulations. Results show that U.S. agricultural soils sequestered Tg CO2 -C year-1 in SOC (at a depth of 3.5 m) during 1960-2018 and emitted Tg N2 O-N year-1 and Tg CH4 -C year-1 , respectively. Based on the GWP100 metric (global warming potential on a 100-year time horizon), the estimated national net GHG emission rate from agricultural soils was Tg CO2 -eq year-1 , with the largest contribution from N2 O emissions. The sequestered SOC offset ~28% of the climate-warming effects resulting from non-CO2 GHG emissions, and this offsetting effect increased over time. Increased nitrogen fertilizer use was the dominant factor contributing to the increase in net GHG emissions during 1960-2018, explaining ~47% of total changes. In contrast, reduced cropland area, the adoption of agricultural conservation practices (e.g., reduced tillage), and rising atmospheric CO2 levels attenuated net GHG emissions from U.S. croplands. Improving management practices to mitigate N2 O emissions represents the biggest opportunity for achieving net-zero emissions in U.S. croplands. Our study highlights the importance of concurrently quantifying SOC-sequestered CO2 and non-CO2 GHG emissions for developing effective agricultural climate change mitigation measures.

Smallholder agriculture in African dryland agroecosystems has limited impact on trophic group composition, but affects arthropod provision of ecosystem services

Agricultural intensification is a major driver of biodiversity loss, but the majority of studies highlighting these threats come from industrialised agriculture in temperate countries of the global North. However, more than 30% of global food production is produced by smallholder farmers, particularly in Africa. We know very little about the impact of these farming practices on arthropod communities and associated ecosystems in dryland agroecosystems. We investigated the trophic group composition of arthropod communities (detritivorous, herbivorous, predatory & mixed feeders) and levels of associated ecosystem functions in replicated maize fields, paired adjacent natural bushveld habitats and the edge habitats between them in north-eastern Namibia and central-eastern Botswana during the dry and wet seasons. Predator activity densities differed significantly between habitats depending on the season, with higher numbers in natural habitats in the wet season but lower numbers in the dry season compared to maize fields. In general, edge habitats had higher numbers of predators than the other habitats. Predator attack rates on artificial caterpillars in both seasons and dung removal in the wet season were higher in habitats with natural vegetation (natural and edge). However, dung removal in the dry season and herbivory in the wet season were highest in the maize fields, the latter due to high level of fall armyworm infestation. Wet season multifunctionality was higher in natural habitats in Botswana, and to a lesser extent in Namibia, than in maize fields. Smallholder agriculture is not detrimental to decomposers, herbivores and mixed feeders compared to adjacent natural habitats, but may be detrimental to the provision of some ecosystem services. These results highlight the challenge of sustainably managing dryland agricultural land that is marginal for crop production, while providing smallholders with an optimal environment to benefit from the ecosystem services associated with arthropod communities. New conservation agriculture practices need to support the production of higher and more stable yields over time, while maintaining the limited impact of smallholder agriculture on biotic communities.

Effects of different tillage and residue management systems on soil organic carbon stock and grain yield of rice–wheat double cropping system

Of late, intensive agricultural practices are often associated with many negative implications for soil systems, such as decline in soil organic matter and biological diversity, and increase in the risk of soil erosion, and degradation of soil physical quality. However, conservation agriculture (CA) offers minimum soil disturbance, improving and creating more efficient use of natural resources, enhancing use efficiency of external inputs and increasing soil functioning, organic matter content, and biodiversity. However, CA practices need to be redefined at the specific field level or growing conditions to promote sustainable production system without deteriorating soil health, and to manage profitability. Therefore, a fixed-site field experiment was conducted to evaluate the effects of different tillage and residue management practices; CT0 (puddled transplanted rice followed by conventional tilled wheat sown with residue removal); CTR (puddled transplanted rice followed by conventional tilled wheat sown with residue retention); NT0 (direct seeded rice followed by zero-tilled wheat sown with residue removal); NTR (direct seeded rice followed by zero-tilled wheat sown with residue retention) on soil organic carbon (SOC) stock and grain yield of rice–wheat double cropping system. The results showed that the mean SOC stock increased by 31%, 21.9% and 15.3% and by 35.2%, 22% and 17% under NTR, CTR, and NT0 compared with CT0. Furthermore, the SOC sequestration rate in NTR was significantly higher than other treatments. Particulate organic carbon (POC) concentration was 58.4% higher in 0–15 cm than 15–30 cm soil layer, and the maximum concentration was recorded under NTR and minimum was under CT0. The highest average rice grain yield was recorded under CTR, which was 5.5%, 16.2% and 24.3% higher than CT0, NTR and NT0, respectively. Both NTR and CTR produced more average wheat yield, which was 8.4% and 8.5% higher than CT0 and NT0, respectively. Principal component analysis (PCA) also showed that cumulative cropping system yield and SOC were increased under CTR, NTR as compared to other treatments. Therefore, it can be drawn that residue retention could be a useful management practice to increase SOC stock and grain yield under both tillage practices in the rice–wheat cropping system.

Minimum tillage as climate-smart agriculture practice and its impact on food and nutrition security.

Minimum tillage (MT) is a sustainable farming practice that limit soil disturbance only to planting stations while leaving the rest of the soil undisturbed. It is an important component of conservation agriculture, which aims to raise agricultural productivity, improve the livelihoods of farmers and build resilient farming systems. Despite the growing empirical literature on its adoption and benefits, there is a paucity of empirical evidence on the heterogeneous effect of length of MT adoption on household welfare. This study uses plot-level and household data combined with geo-referenced historical weather data to provide microeconomic evidence of the impact of MT on maize yields, food and nutrition security, and farm labor demand in Ghana. We account for potential selection bias and omitted variable problems by using an ordered probit selection model to estimate two transition-specific treatment effects: from conventional tillage systems to short-term MT adoption and from short-term to long-term MT adoption. The empirical results show that longer cropping seasons of MT adoption significantly increases maize yields and dietary diversity by about 4.33% and 14.22%, respectively, and decreases household food insecurity and labor demand by 42.31% and 11.09%, respectively. These findings highlight the necessity of developing and implementing programs that promote and help smallholder farmers to sustain its adoption for longer cropping season.

Conservation agriculture, nitrogen and residual sulphur effects on maize (<i>Zea mays</i>) growth and yield in a long-term maize-Indian mustard (<i>Brassica juncea</i>) system

A field experiment was conducted during rainy (kharif) seasons of 2020–21 and 2021–22 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to assess the effects of nitrogen and residual sulphur (S) on maize crop in the 11th year of a long-term conservation agriculture (CA)-based maize (Zea mays L.)-Indian mustard [Brassica juncea (L.) Czern.] cropping system. The CA-based practice CA3 [ZT maize (ZTMz) + mustard residue (MsR) + brown manuring (BM) – ZT mustard (ZTMs) + maize residue (MzR)] resulted in greater maize plant height and dry weight than other CA and CT systems except CA4 [ZTMz + mungbean residue (MbR) – ZTMs + MzR – ZTMb + MsR], which had comparable plant height and dry weight. The CA3 increased maize dry weight by 9% and 11.7% over CT in 2020–21 and 2021–22, respectively. On the contrary, CA4 exhibited highest root length, root mass, and root volume densities in both years, and CA3 was comparable. It gave significantly higher grain yield than other treatments except CA3 and CA2 (ZTMz + MsR- ZTMs + MzR), which were comparable. The 100% and 75% recommended dose of N gave comparable grain yield under all CA-based treatments, indicating a saving of 25% N (~37.5 kg N/ha), mainly under CA practices. This highlights N economization over times in CA system. The 100% and 50% S applied to mustard could not show any significant residual effect on maize grain, stover and biological yields. Interactions between CA practices and N treatments for grain yield was significant but between CA and residual S, treatments were statistically similar. Thus, this study underscores the importance of CA framework for enhancing yield and income through better N and S management/savings in maize-mustard system.

Climate Smart Irrigation Practices for Improving Water Productivity in India: A Comprehensive Review

India, supporting 17% of the global population, from limited land (2.4% of the world's total) and freshwater resources (4%), faces severe water scarcity issues. The country experiences heightened challenges due to a monsoon climate leading to floods and droughts. Irrigation efficiency in India is 35-40% and irrigated area ~48.9%. To meet the demands of a large or growing population in limited land and water resources, climate-smart irrigation practices (CSIPs) are imperative. These practices not only increase yield but also precisely supply water, reduce water application volume, and enhance soil health under changing climate conditions. Precision water management technologies includes; advanced agro-techniques, micro-irrigation, conservation agriculture, crop diversification, integrated farming systems, and water harvesting. Micro-irrigation, encompassing drip and sprinkler systems, emerges as a critical solution for efficient water use. Techniques like Surface Drip Irrigation and Sub-surface Drip Irrigation (SSDI) not only save water but also enhance nutrient transport and reduce labor costs. The automation of micro-irrigation through sensors and wireless communication revolutionizes traditional practices, ensuring precise water management and boosting agricultural productivity. In addition, advanced agro-techniques, including laser land leveling, furrow-irrigated raised beds, aerobic rice cultivation, system of rice intensification, ground cover cum rice production system and Saguna rice technique have good potential to save water and improve water productivity. Implementing these advanced agro-techniques not only conserves water but also contributes to sustainable agriculture by improving overall water productivity, reducing environmental impact, and enhancing crop productivity. The integration of conservation agriculture (minimum soil disturbance, crop residue cover and crop diversification), integrated farming systems (combine diverse agricultural activities synergistically), and water harvesting is imperative for sustainable water management. This review paper systematically compiles climate-smart irrigation practices, including precision water management, combined with conservation agriculture, crop diversification, integrated farming systems, and water harvesting. This review paper offers researchers a comprehensive understanding of different CSIPs, assessing their impact on water conservation, increased crop and water productivity, and sustainability amid climate change. Farmers can gain practical understandings of CSIPs, while policymakers obtain essential information for addressing national water mission goals.

Nitrogen dose and placement in conservation agriculture for augmenting cropgrowth, productivity and profitability of Indian mustard (<i>Brassica juncea</i>)

Optimization of nitrogen (N) fertilization is vital for minimizing losses and realizing the yield potential of Indian mustard [Brassica juncea (L.) Czern.] under different tillage and residue management options. Hence, a field experiment was conducted during winter (rabi) seasons of 2021–22 and 2022–23 at research farm of ICAR-Indian Agricultural Research Institute, New Delhi to study the effect of nitrogen placement methods under conservation agriculture (CA) for augmenting crop growth, productivity and profitability of Indian mustard. Experiment consisted a split-plot design with three crop establishment practices (CEP) [ZT-R, Zero tillage without residue retention; ZT+R, Zero tillage with residue; CT, Conventional tillage] in main-plots and nitrogen placement methods (NPM) [control (no N); recommended dose of N (RDN)-conventional; RDN-SSB (subsurface band placement of second N split along the crop rows); 80% RDN-SSB] in sub-plots. The ZT+R enhanced crop growth rate by 6.0–36.1% over CT at various crop stages. The ZT+R reported higher soil moisture by 9–20.7% over CT and ZT-R. Significantly superior seed yield (14.3–28.5%), net return (20.5–53.9%) and benefit cost ratio (21.8–79.0%) was obtained with ZT+R over ZT-R and CT while RDN-SSB recorded 7.3–9.1% higher seed yield over other treatments. Statistically at par results were obtained under RDN-conventional and 80% RDN-SSB for yield attributing characters and seed yield delineating that a saving of 20% N in mustard production is possible without compromising yield and this can reduce environmental footprint as well. Therefore, this study concluded that the residue retention under ZT along with subsurface N placement in mustard crop gives better vegetative growth, yield attributes and yield with a potential to save 20% N and can be opted in semi-arid Indo-Gangetic plains and similar agro-ecologies.

Effects of Intercropping on Maize and Soybean Yield Performance, Land Equivalent Ratio, and Maize Leaf Area in Conservation Agriculture

Maize-soybean intercropping systems as a conservation farming practice are receiving increased focus from the scientific community. This is because of the advantages of intercropping, especially nutrient benefits through cereal-legume interactions, alternative sustainable methods to manage biotic stress (pests, diseases, weeds), and crop failure risk management due to erratic weather. In addition, smallholders in developing countries commonly use intercropping to produce crops. In Uganda, 40% of smallholder farmers are practicing intercropping yet no adequate location-specific information is available to inform their practice. Farmers who adopted conservation farming practices did not mulch their maize due to drudgery associated with collecting mulch. This study evaluated the effect of two tillage methods (T1 = Conventional tillage using ox drawn mould board plough, T2 = Minimum tillage using ox drawn ripper) and five soil cover practices (SC1 = Mulched Maize, SC2 = Control no mulch, SC3 = Two rows of soybean in between one row of maize, SC4 = One row of soybean in between one row of maize, SC5 = Sole soybean) on maize and soybean yield performance. The trials were established for 4 rainy seasons on a sandy loam ferrosol at National Agricultural Research Organization Institute in Lira, Uganda. Soil cover practice had a significant effect on maize and soybean crop Yield. Mulching significantly increased maize yield and LAI. The LER for both intercropping partterns were above 1.2. Tillage methods were not significantly different in determining crop performance. The practice of minimum tillage should also be adopted because it enhances the positive effects of soil cover (intercropping). We recommend farmers to adopt the intercropping pattern of one row of soybean in between maize row spaced at 75 × 30 cm for better LER, and crop performance. This intercropping pattern maximizes on available resources to deliver better output in conservation farming. Maize crop generally performed better during first season as compared to second season. We recommend farmers to utilize the first rains as the main maize production season.

Conservation agricultural practices for improving productivity and soil healthunder Rice-linseed cropping system in Vertisol

Conservation Agriculture is a farming system that can prevent losses of arable land while regenerating degraded lands (Vlek and Tamene, 2009). Dumanski et al. (2006) explained that conservation agriculture is the integration of ecological management with modern, scientific, agricultural production. It promotes maintenance of a permanent soil cover, minimum soil disturbance, and diversification of plant species. Lal (2001) explained the historical development of agriculture with tillage being a major component of management practices. No-tillage and direct seeding is an effective crop production method for reducing production costs and soil conservation (Huang et al., 2011). Rice – based cropping systems form an integral part of agriculture in Chhattisgarh. Several intensive rice based cropping systems have been identified and are being practiced by the farmers. However, suitable rice based cropping has to be evaluated, to assess the stability in production. Inclusion of oilseeds in the cropping system is more beneficial than cereals followed by cereals (Kumpawat, 2001).

Sustainable intensification of oilseed brassica based production systems under semi-arid climates

Technologies to decrease non-renewable energy use in agriculture production may recuperate the energy balance and C emission in the atmosphere. Conservation Agriculture (CA) practices are getting pace world-wide to answer declining factor productivity, deteriorating soil health, climate change, farm profitability and sustainability. Permanent beds with residue retention (PB+R) improved mustard seed yield (15.4%), system grain yield (10.6%), consumed less C input (-17%) and C foot prints (-25%), and recorded more C output (12%), C net (21%), C efficiency (47%) and C sustainability (47%) compared to conventional tillage without residues (CT-R). Diversification of traditional fallow-mustard (F-M) system with maize-mustard rotation (Mz-M) increased system grain yield (142.9%), sustainable yield index (376.5%), production efficiency (177.2%), economic efficiency (94%)and irrigation water productivity (66%) compared with F-M under CT-R.

Impact of conservation tillage and agronomic biofortification strategies on soil health and grain quality aspects under soybean–wheat cropping system

A field experiment was initiated in 2018 at ICAR-IISR Indore (MP), to study the effect of crop establishment techniques and agronomic biofortification methods on grain yield, crop and soil quality aspects under long-term conservation agriculture (CA) based soybean-wheat cropping system. The experiment was laid out in split plot design with two crop establishment techniques and eight agronomic biofortification methods. The results revealed that significantly higher grain yield, lowest soil pH, highest available nutrients (DTPA-Zn and DTPA-Fe), increased soil enzyme (Dehydrogenase) of soybean and wheat under conservation tillage. Among different agronomic biofortification methods soil application of Zn+Fe (DTPA-Zn and DTPA-Fe) reported significantly higher grain yield, compared to control. However, seed inoculation of microbial strains MDSR 14 + MDSR 34reported significantly lowest soil pH, highest soil enzyme. Soybean and wheat grain phytic acid/Zn (<15) and phytic acid/Fe (<10) molar ratio was found significantly lower under conservation tillage and foliar application of Zn+Fe. Thus, in long term, adaptation of conservation tillage along with soil or foliar application of Zn+Fe and seed inoculation of MDSR 14 + MDSR 34 could be prominent options to improve yield, soil and crop quality parameters under CA based soybean-wheat cropping system.

Conservation agriculture based practices sustains productivity and profitabilityand improves health of black calcareous soils undergroundnut based production systems

A field experiment was conducted during 2015 to 2019 at Research Farm of ICAR- Directorate of Groundnut Research, Junagadh, India to study the effects of tillage and residue management practices in two groundnut-based cropping systems. It could be concluded that minimum tillage along with residue application has the potential for higher system productivity, profitability, and improve the soil health.

Nitrogen Use Efficiency Using the 15N Dilution Technique for Wheat Yield under Conservation Agriculture and Nitrogen Fertilizer

Conservation agriculture (CA), which could contribute to sustainable agriculture, maintains or improves soil nitrogen fertility by eliminating tillage (no-tillage). Quantitative assessment of soil constituents is enhanced by stable isotope techniques such as 15N, which are used to better understand nitrogen dynamics. This study was therefore carried out to assess the impact of tillage type and fertilizer application on soil and plant nitrogen fractionation. The trial consisted of two tillage types: no-tillage (NT) and conventional tillage (CT). Three nitrogen doses (82, 115, and 149 kg ha−1) were applied. The experimental design was a randomized complete block with three replications. The Louiza variety of durum wheat was used in this study. Soil nitrogen sequestration was assessed using the stable nitrogen isotope (15N) method. The statistical analysis (ANOVA) showed that, overall, there was no significant difference between tillage types and nitrogen doses for grain and straw yields and grain total nitrogen. In contrast, the effect of both factors and their interaction were significant for straw total nitrogen. There was no difference between tillage types for grain nitrogen use efficiency (NUE), even though NT was superior to CT by 3.5%, but nitrogen doses had a significant effect and a significant interaction with tillage type. When comparing nitrogen doses for each tillage type separately, results showed that the average NUE for grain was 20.5, 8.4, and 16.5%, respectively, for the three nitrogen doses for CT compared with 26.8, 19.0, and 30.6% for NT, indicating clearly the better performance of NT compared to CT. Regarding straw, the NUE is 3.2, 3.5, and 5.4% for CT compared with 3.4, 4.9, and 9.2% for NT. NUE in grain and straw under no-tillage was higher than under conventional tillage in all three nitrogen doses. These results show that soil conservation techniques such as no-tillage and the integrated application of nitrogen fertilizer can be good strategies for reducing soil nitrogen losses.

A systematic review on the impact of incentives on the adoption of conservation agriculture: new guidelines for policymakers and researchers

ABSTRACTFacing the new challenges of sustainable development in the agricultural sector requires transitioning toward sustainable systems, such as conservation agriculture (CA) practices. Despite several decades of work to diffuse CA technologies, the adoption rate remains below expectations in several countries. Different policy scenarios have been adopted to address this situation, mainly incentives. However, evidence of their effectiveness and possibilities of reinforcement are not clearly defined in the literature. The purpose of this systematic review is to examine the evidence of the impact of incentives on the adoption of conservation agriculture practices to help academics and politicians understand how to effectively spread sustainable innovations such as CA. Results show that four kinds of incentives are evaluated Agri-Environment Schemes (AES)/Payments for Ecosystem Services (PES), input subsidies, direct subsidies, and market-based incentives. The impact of PES and input subsidies was significant and positive for the diffusion of CA. However, the component of minimum tillage dissemination was not significantly affected by PES agglomeration payments or greater levels of direct subsidies, respectively. The incentives investigated are not sufficiently diversified in type, which consequently limits their usefulness. Three recommendations for the deployment of incentives were made in light of these findings.

Unlocking the potential of conservation agriculture for soil carbon sequestration influenced by soil texture and climate: A worldwide systematic review

Conservation Agriculture (CA) systems have gained significant attention as a sustainable cropping approach that not only improves crop yields but also contributes to climate change adaptation and mitigation through enhanced soil organic carbon (SOC) sequestration. However, a comprehensive understanding of the influence of soil texture and climate conditions on SOC sequestration under CA remains limited. To address this knowledge gap, we conducted a systematic review using the PRISMA method, analyzing data from 35 peer-reviewed articles encompassing 71 field experiments and 451 observations worldwide. Our findings demonstrate the substantial positive impact of CA on SOC sequestration, with an overall increase of approximately 78%. Remarkably, only a mere 2% of observations reported neutral effects, while 20% indicated adverse outcomes. Notably, SOC sequestration rates were highest in tropical regions experiencing dry winters, reaching an impressive 2.50 Mg/ha/year in the topsoil layers. Moreover, fine and moderate textured soils, such as clay, clay loam, loam, and clay sandy, exhibited higher SOC sequestration rates (20-27%) compared to coarse-textured soils dominated by sandy proportions (9%). These findings emphasize the significance of climate conditions and soil texture in shaping the impact of CA on SOC sequestration.