Improve Soil Organic Carbon Research Articles

Biochar Addition in Flooded Paddy Soil for Ameliorating the Effects of Elevated Carbon dioxide (eCO2)

Improving soil organic carbon by biochar application is of concern in flooded rice soils. However, the effect of biochar on soil physico-chemical and biological properties under increasing levels of CO2 is limited and needs investigation. The present study examined the response of soil carbon pool, and soil enzyme activities of rice upon application of biochar under elevated carbon dioxide (eCO2) - 55030 μmol.mol−1 level. The study was carried out in open-top chambers (OTC) under a rice-rice (Oryza sativa L.) cropping system in 2020. A set of OTCs at ambient CO2 (415 ± 10 μmol mol−1 (aCO2)) served as a check with and without biochar application. The fourth OTC maintained eCO2 without the application of biochar. Rhizosphere soil samples from three critical crop stages viz., active tillering, flowering, and maturity were analyzed for various physico- chemical and biological properties. Most soil biological parameters, specifically soil enzymes, β – glucosidase, urease, and phosphatases, exhibited significant changes during the flowering stage in biochar applied e(CO2) treatment. The per cent increase of 46.8 %, 30.2 %, 18.75 %, and 51.2 % over ambient CO2 in soil organic carbon (SOC), soil microbial biomass carbon (SMBC), oxidizable carbon (OC), and water-soluble carbon, respectively, was observed. This study emphasized that biochar can improve the soil C pool and enzyme activities under anticipated climate change.

Improving Soil Organic Carbon Predictions from Sentinel‑2 Soil Composites by Assessing Surface Conditions and Uncertainties

Improving Soil Organic Carbon Predictions from Sentinel‑2 Soil Composites by Assessing Surface Conditions and Uncertainties

Partial substitution of chemical fertilizer by organic fertilizer benefits grain yield, water use efficiency, and economic return of summer maize

Partial substitution of chemical fertilizer with organic fertilizer (PSCFOF) is being increasingly recognized as a promising approach for achieving sustainable agriculture. However, comprehensive evaluation of the effect of PSCFOF on the grain yield, water use efficiency (WUE), and its economic return of summer maize is lacking. In this study, field experiments examining the following five treatments were conducted over the 2019 and 2020 growing season: T1, application of chemical NPK fertilizer alone; and T2–T5, substitution of 15%, 30%, 45%, and 60%, respectively, of the chemical N rate of T1 with organic fertilizer. Compared with T1, the other treatments reduced the soil bulk density, and improved soil organic carbon content and the percentage of macro-aggregates (≥0.25 mm) in the 0–20 cm soil layer. The grain yield and WUE of T2 and T3 were significantly higher than that of T1, where as T1, T4 and T5 had similar effect. The higher grain yield and WUE under T2 and T3 treatments may related to its strong root system, higher soil water content, and elevated plant N uptake, which further improved the post-silking photosynthetic capacity, biomass production, and harvest index. The results of the economic benefit analysis indicated that, T2 and T3 increased the net benefit by 2257 and 1404 CNY ha-1, respectively, compared to T1. However, the net benefit was reduced under T4 and T5 treatments. In conclusion, by comparison with T1, T2 and T3 improved the grain yield, WUE, and economic benefit of summer maize. Although T2 can achieve the optimal economic benefits in a short-term, T3 may be a better choice from the perspective of long-term ecological and economic benefits, because of its greater potential to reduce chemical N fertilizer application rate.

Improving soil organic carbon mapping with a field‐specific calibration approach through diffuse reflectance spectroscopy and machine learning algorithms

AbstractDetailed mapping of soil attributes is often not viable due to the high cost of wet‐chemical laboratory analysis, which requires a large number of samples. Thus, we evaluated whether the prediction of SOC contents through field‐specific diffuse reflectance spectroscopy (DRS) can increase the amount of samples available to SOC mapping through data interpolation. For such, we tested the performance of the partial least squares regression (PLSR), random forest (RF) and gradient boosting tree (GBT) algorithms to model and predict SOC. The field‐specific calibration approach proposed here proved to be suitable for predicting SOC content on soil samples, reducing the dependence on wet‐chemical soil laboratory analyses for mapping. With such SOC content prediction, the higher amount of samples to be used for spatial interpolation can be increased, leading to more accurate SOC maps that can be applied for site‐specific management.

Alleviating Soil Acidification and Increasing the Organic Carbon Pool by Long-Term Organic Fertilizer on Tobacco Planting Soil

Long term tobacco planting leads to soil acidification. A ten-year experiment with various fertilization treatments (no fertilization (CK), chemical fertilizer (CF), organic-inorganic compound fertilizer (OCF), and organic fertilizer (OF)) was carried out between 2010 and 2020 in a continuous cropping system of Nicotiana tabacum in the brown soil of eastern China, to assess the effects of organic fertilizer on the improvement of tobacco planting soil acidification. The results indicated that treatments OCF and OF reduced the soil exchangeable acid content, of which the exchangeable aluminum showed the largest reduction by 51.28% with the OF treatment. In contrast, treatment CF showed more significant increases in exchangeable aluminum (Al) and Al saturation, and also apparently increased soil NO3−-N, NH4+-N and nitrification potential (NP) than other treatments. Treatments of OCF and OF significantly increased the total amount of exchangeable base (EBC) by 37.19% and 42.00% compared with CF, respectively. Redundancy analysis (RDA) showed that NP, NH4+-N, and NO3−-N were the important factors indicating soil acidification, while EBC and exchangeable K were the significant factors restricting soil acidification. Inevitably, OCF could improve the soil organic carbon pool and labile organic carbon pool. The structural equation model (SEM) showed that OCF treatment increased the soil organic carbon pool mainly by inhibiting soil nitrification and reducing the content of exchangeable Al. In conclusion, both OF and OCF treatments were effective methods to alleviate tobacco planting soil acidification, however OCF had more advantages in improving soil organic carbon pool.

Dynamics and composition of soil organic carbon in response to 15 years of straw return in a Mollisol

Crop straw return is being widely applied as a sustainable soil management practice to improve soil organic carbon (SOC) storage in intensive agricultural ecosystems. However, the dynamics and chemical composition of SOC under long-term straw return are not fully understood. Based on a 15-year field experiment with soybean (Glycine max (L.) Merrill.)–maize (Zea mays L.) cropping system, we studied SOC temporal dynamics under no fertilization (NF), mineral fertilizers (NPK) and mineral fertilizers with straw return (NPKS). Meanwhile, we determined five labile carbon (C) pools, i.e., microbial biomass C (MBC), water-soluble organic C (WSOC), light fraction C (LFC), readily oxidizable organic C (ROC), and particulate organic C (POC), as well as δ13C values and organic functional groups of soil organic matter (SOM). After 15-year application of continuous straw return with mineral fertilizer application, SOC content increased by 14.2%. The δ13C values of SOC increased with time under all treatments, and its positive relationship with cumulative maize C input indicated a larger C contribution to SOC from maize than soybean residues. The NPKS treatment significantly increased the contents of MBC, WSOC, LFC, ROC, and POC and their proportion in SOC, compared with the NF treatment. The aliphatic and aromatic relative peak areas were significantly affected by straw return, with an increasing relative peak area at 2930 cm−1 and decreasing at 1620 cm−1, respectively. Our results demonstrate that straw return could continuously increase SOC in an inter-annual rotation of soybean and maize cropping system in Mollisol. Meanwhile, long-term fertilization can alter SOM chemical composition, with lower humification degree under the combined application of straw and mineral NPK fertilizers.

Management of Nano-black Carbon, Phosphorous and Bio Fertilizer Improve Soil Organic Carbon and Ensilage Biomass of Soybean and Maize

ABSTRACT Field experiments were conducted for two-consecutive summer seasons of 2016–17 and 2017–18 at Agriculture Research Institute Mingora Swat, Pakistan, on soybean and maize under soybean-wheat (S-W) and maize-wheat (M-W) cropping systems. Three peach sources were used as a residues, its compost and its Nano-black carbon, three phosphorus-rates (50, 75 and 100 kg-ha−1) and two beneficial microbes (PSB and Trichoderma) were tested for improvement of ensilage biomass of maize and soybean, and soil organic-carbon (SOC) under both cropping systems. The results revealed that all the treated plots produced highest SOC compared to the control plots under soybean and maize cropping system. Improved SOC was noted with the OS amendment of Nano-black carbon in both cropping systems. Whereas minimum SOC was noted in soybean experimentation with compost while in maize plot reduced SOC was noted with peach residues incorporation. Beneficial microbes had a significant effect on SOC and improved SOC was recorded with soil application Trichoderma as compared to seed inoculation with PSB in soybean and maize plots. Phosphorus levels had also significant effect on SOC and highest SOC was recorded at 100 kg P ha−1 followed by 75 kg P ha−1 whereas the smallest SOC was recorded with 50 kg P ha−1. Ensilage highest biomass of the both crops was noted with peach Nano-black carbon, followed by compost and reduced biomass were noted with peach residues application. Among the P-rate, increased ensilage biomass was recorded with 100 kg P ha−1application while in case of beneficial microbes application, soil application of Trichoderma produced highest biomass as compared to seed inoculation with PSB.

Soil greenhouse gas emissions, organic carbon and crop yield following pinewood biochar and biochar–manure applications at eroded and depositional landscape positions: A field trial in South Dakota, USA

AbstractSoil amendments can help reduce greenhouse gas (GHG) emissions and increase soil organic carbon (SOC) and crop yield. However, most biochar studies have been conducted on single soil type under controlled conditions. To address this limitation, the aim of this research was to investigate how field biochar and manure applications affect soil quality, plant productivity, and GHG emissions at eroded (sandy loam) and depositional (clay loam) positions in a climate transition zone (udic to ustic and mesic to frigid temperature). A field study was established in 2013 in South Dakota, USA, under a corn–soya bean rotation. Soil treatments included biochar, manure, a manure and biochar mixture, and a control (untreated soil). Soil properties (pH, electrical conductivity (EC), SOC, available nitrogen, available phosphorus and available potassium) were measured in 2017. Plant productivity parameters in 2016 and 2017 and GHG fluxes were measured during the 2016 and 2017 growing seasons. Compared with the control, SOC increased under all treatments at the eroded position (biochar 26%, manure 24%, and manure–biochar mixture 15%) and increased under biochar (25%) and the manure–biochar mixture (25%) at the depositional position. Plant parameters were similar under all treatments at both positions. Area‐scaled CO2 fluxes were lower in soils treated with biochar compared with the control at the eroded landscape position but not at the depositional landscape position. Area‐scaled N2O fluxes were lower in soils treated with biochar at both positions. Furthermore, the biochar–manure mixture treatment emitted lower area‐scaled N2O fluxes compared with manure alone at both positions. This study suggests that for eroded and depositional landscape positions, biochar can improve soil organic carbon and the effects of the biochar and biochar–manure mixture on GHG emissions vary based on the soil texture.

Linking soil carbon availability, microbial community composition and enzyme activities to organic carbon mineralization of a bamboo forest soil amended with pyrogenic and fresh organic matter

Despite fresh and pyrogenic organic matter have been widely used as amendments to improve soil organic carbon (SOC) storage, mineralization that links to C quality and soil temperature, microbial community composition and enzyme activity remain poorly understood. This study aims to explore the effects of amendments (bamboo leaves and its biochar) and incubation temperature on mineralization, and disentangle the relationships of SOC mineralization with chemical composition of SOC, labile organic C, microbial community composition, and activities of enzymes in a subtropical bamboo forest soil. Results showed that cumulative soil CO2 emissions ranked as bamboo leaf (Leaf) > bamboo leaf biochar (Biochar) > Control, regardless of the incubation temperature. Compared to the control, the Leaf treatment markedly increased, whereas the Biochar treatment decreased, the temperature sensitivity of SOC mineralization (P < 0.05). The cumulative soil CO2 emission was positively correlated (P < 0.05) with water-soluble organic C (WSOC), microbial biomass C (MBC), O-alkyl C and alkyl C contents, and activities of β-glucosidase and dehydrogenase, but negatively correlated (P < 0.01) with aromatic C content, regardless of the incubation temperature. This indicated that the lower SOC mineralization rate and lower temperature sensitivity in the Biochar (cf. Leaf) treatment were intimately associated with the lower WSOC, MBC, O-alkyl C content, and β-glucosidase and dehydrogenase activities, and higher aromatic C content in the Biochar. The high relative abundance of bacteria relating SOC mineralization included Rhizobiales, Sphingobacteriales and JG30-KF-AS9, whereas that of fungi included Eurotiales, Sordariales, Agaricales and Helotiales. Our results revealed that the application of pyrogenic organic matter, as compared to the application of fresh organic matter, can reduce SOC mineralization and its temperature sensitivity in a subtropical forest soil by limiting the availability of C and microbial activity, and thus has a great potential for maintaining soil carbon stock in subtropical forest ecosystems.

Gypsum and pressmud amelioration improve soil organic carbon storage and stability in sodic agroecosystems

AbstractSalinity–induced land degradation poses a threat to environment and food production globally. Farmers' participatory research (2014–18) was carried out to assess the potential of gypsum (Gyp) and pressmud (PM) in alleviating the sodicity stress, and improvement in soil organic carbon (SOC) pools and its stability in the Trans Indo–Gangetic Plains of India. Intensive rice–wheat cultivation using alkali water increased soil pH, exchangeable sodium percentage (ESP), and bulk density (BD) causing a net depletion in SOC. Gypsum (supplies soluble Ca2+) and pressmud (mobilizes native CaCO3) mediated amelioration (Gyp + PM) significantly decreased soil sodification and compaction, and improved total organic carbon (TOC; 32%–64%) over the unamended control. Higher left–over C for SOC stabilization, crop biomass, and rhizodeposition returned through Gyp + PM significantly improved SOC pools and C sequestration culminating in ~25% yield superiority over the unamended control. Within SOC pools, highest proportion was equally retained in very labile and non–labile C pools. On average, the passive pool contained ~45% of TOC; albeit to a greater contribution through PM followed by Gyp + PM and Gyp. Rice–wheat system yield (RWSY) was positively correlated with SOC pools and indices while negatively correlated with soil pH, ESP, BD, CaCO3, and recalcitrant index. Multiple regression analysis showed stratification ratio, CaCO3, sensitivity index, and BD as key variables for yield prediction under the existing levels of soil sodicity. The key insights suggest ecosystem‐based approach using Gyp + PM in restoring the degraded lands, enhancing crop resilience and system (SOC enrichment and storage) stability, and achieving UN–Sustainable Development Goals related to food security and land degradation neutrality.

Correction to: Improving soil organic carbon and microbial functionality through different rice straw management approaches in rice–wheat cropping sequence

Correction to: Improving soil organic carbon and microbial functionality through different rice straw management approaches in rice–wheat cropping sequence

Improving soil organic carbon and microbial functionality through different rice straw management approaches in rice–wheat cropping sequence

Improving soil organic carbon and microbial functionality through different rice straw management approaches in rice–wheat cropping sequence

Cowpea Crop Response to Mineral and Organic Fertilization in SE Spain

Mineral fertilization is considered to be useful for improving soil fertility and yields. However, its use is linked to global warming and soil and water pollution by its rapid mobilization. On the other hand, organic fertilization is recommended to maintain or improve soil organic carbon and total nitrogen stocks while contributing to climate change mitigation. The main goal of this study was to assess the effect of two different fertilizer types, mineral and organic, during three cowpea crop cycles on the soil’s physicochemical properties, enzyme activities, crop yield, crop quality and nutritional composition when considering two cowpea cultivars (Feijão frade de fio preto (FP) and Feijão frade de fio claro (FC)). The use of mineral fertilizers was seen to contribute to improved soil fertility due to the increase in soil properties, such as recalcitrant carbon, total nitrogen, ammonium content, available K and available Mg. On the other hand, organic fertilizers only increased the nitrate content in the soil. There were no differences in terms of cowpea crop yield, quality and nutritional composition by fertilizer type. Thus, both fertilizer types contributed to the same crop yield and quality, and thus the use of organic fertilizers can result in a sustainable alternative for maintaining cowpea crop yield and quality.

Water management and soil amendment for reducing emission factor and global warming potential but improving rice yield

Alternate wetting and drying (AWD) for growing rice improves water productivity (WP), minimize methane emission and net ecosystem carbon balance (CO2), but might be responsible for increased nitrous oxide emissions. The combined effects of water management and different organic manure application on methane emission, carbon dioxide and nitrous oxide fluxes, emission factor (EF) and WP are not well documented, which has been evaluated during dry seasons of 2018 and 2019. AWD and continuous flooding (CF) were imposed in NPKSZn, cowdung (CD), poultry manure (PM) and vermicompost (VC) treated plots. Closed chamber techniques were used for determining emissions of greenhouse gases. In comparison with CF, the AWD significantly reduced total GWP by 15–44% depending on soil amendments and 2–29% net ecosystem carbon balance (CO2); but additional N2O contribution to GWP was about 0.61–1.18% compared to sole chemical fertilizer treatments. Depending on soil amendments, the AWD reduced EF of CH4 (22–36%) but increased WP by 25–27% compared to CF system along with 14–43% reduction in GHG intensity (GHGI). Vermicompost treatment had the lowest GHG emission, GWP, EF and GHGI than cowdung, poultry manure under both irrigation methods. Rice yield varied because of soil amendments but not with irrigation methods. Use of vermicompost improved soil organic carbon (SOC) storage significantly than cowdung and poultry manure. In conclusion, AWD practice and amendment of rice soil with vermicompost could be an effective strategy for reducing GHG emission, GWP, EF and GHGI without sacrificing rice yield.

Bio-Organic Fertilizer: A Green Technology to Reduce Synthetic N and P Fertilizer for Rice Production.

Decomposed organic materials, in combination with plant growth-promoting bacteria (PGPB), are environmentally friendly and reduce synthetic fertilizer use in rice production. A bio-organic fertilizer (BoF) was prepared using kitchen waste (79%), chita-dhan (unfilled rice grain) biochar (15%), rock phosphate (5%), and a consortium of 10 PGPB (1%) to supplement 30% nitrogen and to replace triple superphosphate (TSP) fertilizer in rice production with an improvement of soil health. PGPB were local isolates and identified using 16S ribosomal RNA partial gene sequences as Bacillus mycoides, Proteus sp., Bacillus cereus, Bacillus subtilis, Bacillus pumilus, Paenibacillus polymyxa, and Paenibacillus spp. Isolates could fix N2 by 0.7–1.4 g kg–1, solubilize 0.1–1.2 g kg–1 phosphate, and produce 0.1–40 g kg–1 indoleacetic acid. The performance of BoF was evaluated by 16 field experiments and 18 farmers’ field demonstration trials during the year 2017–2020 in different parts of Bangladesh. Performances of BoF were evaluated based on control (T1), full synthetic fertilizer dose of N, P, and K (T2), BoF (2 t ha–1) + 70% N as urea + 100% K as muriate of potash (T3), 70% N as urea + 100% P as TSP + 100% K as muriate of potash (T4), and 2 t ha–1 BoF (T5) treatments. At the research station, average grain yield improved by 10–13% in T3 compared with T2 treatment. Depending on seasons, higher agronomic N use efficiency (19–30%), physiological N use efficiency (8–18%), partial factor productivity (PFP)N (114–150%), recovery efficiency (RE)N (3–31%), N harvest index (HIN) (14–24%), agronomic P use efficiency (22–25%), partial factor productivity of P (9–12%), AREP (15–23%), and HIP (3–6%) were obtained in T3 compared with T2 treatment. Research results were reflected in farmers’ field, and significant (P < 0.05) higher plant height, tiller, panicle, grain yield, partial factor productivity of N and P were obtained in the same treatment. Application of BoF improved soil organic carbon by 6–13%, along with an increased number of PGPB as compared with full synthetic fertilizer dose. In conclusion, tested BoF can be considered as a green technology to reduce 30% synthetic N and 100% TSP requirements in rice production with improved soil health.

Effects of residue mulching amounts on metabolic footprints based on production and respiration of soil nematodes in a long‐term no‐tillage system

AbstractResidue mulching has been adopted to improve soil organic carbon and to prevent soil erosion and degradation, which in turn promote the sustainable development of soil ecosystems. Nematode metabolic footprints provide information about the responses of nematodes to resources and also help in quantifying the contributions of nematodes to ecosystem functions and services. However, how production and respiration components of nematode metabolic footprints vary in different mulching amounts is less clear. Therefore, to explore the impact of different mulching amounts on the production and respiration of nematode trophic groups, soil samples were collected from four mulching treatments (without mulching, with 33%, 67%, and 100% mulching of the stover remaining at harvest) at the depths of 0–5 cm and 5–10 cm in a 12‐year long no‐tillage system. Our results proved that the mulching effect on the production and respiration of fungivores was significant, and the production was 71.8%, 62.7%, 71.5% higher and respiration was 67.7%, 61.9%, 70% higher in 100% mulching treatment than without mulching, 33% and 67% mulching, respectively. More basal C flowed into the fungal decomposition pathways and fungivores contributed more to soil carbon sequestration through the decomposition of recalcitrant nutrients from residue at the end of crop growth. There was higher production than respiration in bacterivores and an opposite trend was observed in fungivores. Residue mulching increased the metabolic footprints of nematode communities and carbon use efficiency of fungivores and omnivores and predators and then enhanced the potential of soil carbon sequestration through the metabolic process of different nematode trophic groups.

Early-Season Effects of Wildfire on Soil Nutrients and Weed Diversity in Two Plantations

Abstract This study assessed early-season effects of spontaneous wildfires on soil fertility and weed diversity in two managed plantations – cashew and teak – in Ilorin, Nigeria. Soil pH and nutrients in the topsoils and subsoils of burned and unburned plantations plots after a spontaneous wildfire were analysed. Species diversity and similarity were determined based on the composition and abundances of weed flora two months post-fire. The fire effects on soil nutrients and weed composition in the plantations were evaluated using the canonical correspondence analysis. Burns incidence significantly improved the organic carbon, organic matter, and Ca contents while reducing total N and Mg in both plantations. Twenty-eight weed species were distributed in 9 angiosperm families. Fire differently affected weed composition, abundance and diversity in the plantations. Burning improved soil organic carbon and organic matter contents and restricted Tephrosia bracteolata, Desmodium tortuosum, Daniellia oliveri, Senna obtusifolia and Zornia latifolia to the burned cashew plantation. The occurrence of Euphorbia heterophylla, Eriosema psoraleoides and Crotalaria retusa in the burned teak plantation was associated with a direct fire effect on soil Na and Ca contents. Burning influenced soil nutrients in the studied plantations, but weed diversity increased in the teak plantation and was reduced in the cashew plantation.

Long‐term effects of straw mulching coupled with N application on soil organic carbon sequestration and soil aggregation in a winter wheat monoculture system

AbstractStraw mulching can be affected by N fertilization rate with regard to improving soil organic carbon (SOC) lability, which modifies the net accumulation of SOC and soil aggregation. We conducted a 14‐yr field experiment to determine how straw mulching coupled with N application rates affects crop yield, SOC sequestration as a net gain of SOC, and soil aggregation in a winter wheat (Triticum aestivum L.) monoculture system. Six combinations of two cultivation practices, conventional cultivation (CC) and straw mulching (SM), and three N application rates (0, 120, and 240 kg N ha–1) were compared. Results revealed that SM did not affect wheat yield throughout the 14 yr of cultivation, but increased the SOC stock, SOC lability, and the carbon management index (CMI) in surface soil (0–20 cm). Instead, N application, N120 and N240, increased the wheat production almost equally, and followed a trend for increasing SOC stock: N240 &gt; N120 &gt; N0; however, a different trend for increasing SOC lability and soil CMI (N120 &gt; N240 &gt; N0). Soil macro‐aggregation was increased by SM but decreased with increasing N application. Principal component analysis (PCA) indicated that organic C input was the key to improving SOC sequestration, SOC lability, and soil macro‐aggregation rather than N input, especially high N input (N240) reduced SOC lability and soil aggregation in soil. Consequently, medium N application (N120) may be expected to couple with straw direct‐returning for improving soil productivity and quality in this agro‐system.

Influence of Tillage and Relay Cropping of Berseem in Mustard–Pearl millet System on Soil Quality, Productivity of Crops and Water

In the semi-arid tropics, pearlmillet–mustard (PM–M) is one of the major cropping systems of India. The monocropping of PM–M system has been showing signs of diminutive and decline soil quality, system productivity and profitability from more than two decades. In order to improve the PM-M system productivity and make it profitable through relaying a leguminous fodder crop berseem or Egyptian clover in various tillage and crop seeding (TCS) methods. Relaying berseem (RB) residues provided surface cover in zero-tillage (ZT) system and the needed organic carbon sponge for microbial actions for improvements in soil properties. The shifting of TCS from traditional tilled (TT) to ZT system and RB in standing mustard crop significantly improved soil organic carbon stock, infiltration rate, soil water storage, availability of macro- and micronutrients, biological properties, land use and production efficiency. Improvements in soil properties resulted significantly greater productivity of crops, system and net profit. The TCS with ZT increased the PM–M system productivity by 11% in without RB, while 12% in RB compared with TT system. Results of ZT seeding method saved production cost of PM–M ₹ 8498/ha and had increased net profit ₹ 20,988/ha, whereas those of PM–M in RB saved production cost of ₹ 13,263/ha and increased net profit ₹ 35,538/ha compared with TT, respectively. Among the treatments of TCS, ZT seeding in PM–M cropping system with RB in mustard had greater soil quality parameters, pearl millet equivalent system productivity and net benefits; thus, it is considered the best practice to maintain soil quality, food security and profitability.

Mung bean cover crop improved soil organic carbon and maize yield in a semiarid area

This study aimed to know the potential use of mung bean (Vigna radiata L. Wilzeck) as a cover crop and its effect on soil organic carbon and maize yield were studied. Six cover crop treatments; 250,000, 375,000 and 500,000 plants/ha combined with desiccation times at 28 and 35 days after sowing (DAS) and one control treatment (without cover crop), were tested in a semi-arid area of North Lombok. Maize at a density of 98,000 plants/ha was planted two weeks following the desiccation time. The treatments were arranged in a Randomized Block Design with three replications. The results revealed that the higher cover crop population density with later desiccation time, produced higher above ground biomass, being the highest at 8.3 Mg/ha and the lowest at 2.6 Mg/ha. The highest cover crop biomass improved soil organic carbon by 60%, nitrogen, phosphorous and potash concentrations in plant tissue by 54%, 54% and 63%, respectively, compared to the one in the control treatment. Maize yield also increased by 24% at the highest cover crop density desiccated at 35 DAS. The use of mung bean as a cover crop sounds promising and further studies are needed to explore more of its potential benefits.