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Highlights • Sequestration of more carbon is the key for sustainable management of sloping lands. • No-till with residue retention (NT-RR) enhanced carbon sequestration and retention. • Inclusion of cowpea in a rice-rapeseed system doubled the carbon sequestration. • NT-RR can sequestrate ∼ 6.8–13.7 Mg C ha−1 in a period of 15–30 years in the region. • Restoration of the precious carbon has the potential to mitigate climate change. Abstract Decline in soil organic carbon (SOC) and low biomass production in sloping uplands are of growing concern for sustainable agriculture worldwide. This concern is in general in the Eastern Himalayan regions (EHR) of India in particular. A field experiment was conducted with the objectives to generate additional biomass and sequester more C in coarse-textured sloping lands. This experiment is done for four consecutive years in the EHR, India. The rice (Oryza sativa L.)–rapeseed (Brassica campestris L. var. rapeseed) cropping system was practiced during the first two years (2012-13 to 2013-14) and rice–rapeseed–cowpea (Vigna unguiculata L.) system during the two following years (2014-15 to 2015-16) of the study under different tillage and mulch systems. The tillage system included: 1) CT-RI: conventional tillage (CT) with 100% residue incorporation (RI) and 2) NT-RR: no-till (NT) with 100% residue retention (RR). The mulches included 1) rice straw mulch (SM), 2) Gliricidia sp. mulch (GM), 3) brown manuring mulch (BM)–cowpea grown as intercrop with rice up to 40 days after sowing (DAS), killed with 2,4-D and 4) no mulch (NM). The cowpea, as a cover crop was introduced during 2014 and 2015 as pre-rainy season crop before the sowing of rice to generate additional biomass in the system. The four year total above ground biomass yield of rice and rapeseed didn't vary significantly between CT-RI (31.93 and 17.40 Mg ha−1) and NT-RR (31.86 and 17.46 Mg ha−1), respectively. However, the total above ground biomass yield of cowpea was more under NT-RR (10.75 Mg ha−1) when compared to that under CT-RI (9.79 Mg ha−1). The amount of total biomass (above + below ground) and C added into the soil was more under NT-RR than that under the CT-RI. After 4 cropping cycles, the NT-RR had higher SOC concentration, pool (29.9 vs. 29.1 Mg ha−1), sequestration rate (450 vs. 265 kg ha-1 yr−1) and C retention efficiency (7.7 vs. 4.6%) than those under the CT-RI at 0–30 cm depth. The mulched plots produced more crop biomass (both above and below ground), recycled more C in soils with a trend of relatively more SOC pool (29.7–29.8 vs. 29.0 Mg ha−1), sequestration rate (391–428 vs. 221 kg ha-1 yr−1) and C retention efficiency (6.64–6.94% vs. 4.66%) than those of NM treatment. These results were seen despite difference among the mulch treatments (SM, GM and BM) which were statistically non-significant after 4 cropping cycles. Inclusion of cowpea as cover crop during pre-rainy season in the system doubled the rate of C sequestration (478 kg C ha-1 yr−1). Therefore, the data supports the recommendation of cultivation of the rice–rapeseed system under NT-RR along with cowpea intercropping up to 40 DAS (BM) in rice. Besides this, the inclusion of pre-rainy season cowpea before rice could generate additional biomass and enhance SOC sequestration on upland and sloping hills in the EHR of India and in similar conditions elsewhere. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the effects of tillage and mulch on weed growth, soil moisture storage, productivity and profitability of upland rice during 2012-2013 at Lembucherra, India. Tillage treatments included CT-RI: conventional tillage with 100% residue incorporation and NT-RR: no-till with 100% residue retention. Mulches included rice straw (SM), Gliricidia (GM), brown manuring (BM) and none (NM). CT-RI registered the highest total weed density (89-168 weeds m−2) and biomass (9.6-183 g dry weight m−2) than those for the NT-RR (75-161 weed m−2 and 8-155 g dry weight m−2). In addition, NT-RR stored (122-172 mm) more soil moisture (0-40 cm soil depth) in comparison with that for the CT-RI treatment (110-161 mm) during crop growing season. Tillage treatments did not have the significant effect on yields. NT-RR reduced the cost of cultivation by 31.5% compared with that for the CT-RI. Thus, the net returns under NT-RR were more than those for the CT-RI. The BM recorded the lowest weed biomass and density as compared to that under other mulches. Therefore, cultivation of upland rice using NT along with BM mulching enhanced productivity and profitability of rice cultivation in India. [ABSTRACT FROM AUTHOR]

Field experiments were carried out during rainy (kharif) and winter (rabi) seasons (June–April) of 2008–2010 at Indian Agricultural Research Institute (IARI), New Delhi, to study the productivity, nutrients uptake, iron (Fe) use-efficiency and economics of aerobic rice-wheat cropping system as influenced by mulching and Fe nutrition. The highest yield attributes, grain and straw yields (5.41 tonnes ha−1 and 6.56 tonnes ha−1, respectively) and nutrient uptake in rice was recorded with transplanted and puddled rice (TPR) followed by aerobic rice with Sesbania aculeata mulch. However, residual effect of aerobic rice with wheat straw mulch was more pronounced on yield attributes, grain and straw yields (4.20 and 6.70 tonnes ha−1, respectively) and nutrient uptake in succeeding wheat and remained at par with aerobic rice with Sesbania mulch. Application of iron sulfate (FeSO4) at 50 kg ha−1 + 2 foliar sprays of 2% FeSO4 was found to be the best in terms of all the yield attributes, grain and straw yield (5.09 and 6.17 tonnes ha−1, respectively) and nutrient uptake and remained at par with 3 foliar sprays of 2% FeSO4. Although residual effect of iron application failed to increase the yield attributes, yield and nutrient uptake nitrogen, phosphorus and potassium (N, P, K) except Fe. The highest system productivity, nutrient uptake, gross returns, net returns, B: C ratio and lowest cost of cultivation were recorded with aerobic rice with wheat straw and Sesbania aculeata mulch. Application of FeSO4 at 50 kg ha−1 + two foliar sprays of 2% FeSO4 was found better in respect of system productivity, nutrient uptake, gross returns, net returns, B:C ratio and cost of cultivation in aerobic rice-wheat cropping system. The Fe use efficiency values viz. partial factor productivity (kg grain kg−1 Fe), agronomic efficiency (kg grain increased kg−1 Fe applied), agrophysiological efficiency (kg grain kg−1 Fe uptake), physiological efficiency (kg biomass kg−1 Fe uptake), apparent recovery (%) utilization efficiency and harvest index (%) of applied Fe were significantly affected due to methods of rice production and various Fe nutrition treatments in aerobic rice and aerobic rice-wheat cropping system. [ABSTRACT FROM AUTHOR]

Amid the current environmental crises that exert enormous pressure on the arable lands, there is a need to adopt environment-friendly effective but highly productive conservation agriculture practices to feed the growing world population. Thus, a study was conducted to test the hypothesis that the inclusion of cowpea (Vigna unguiculata L. Walp) live mulch under no-till and reduced tillage in the summer maize (Zea mays L.) – rainy season maize-mustard (Brassica juncea (L.) czern) sequence would enhance agronomic productivity, energy use efficiency, and water productivity while reducing greenhouse gases emissions. Five tillage treatments viz., no-till, no-till-live mulch, reduce tillage, reduce tillage-live mulch, and conventional tillage were evaluated in three times replicated randomized complete block design. Land productivity for maize–maize–mustard system was the highest under reduced tillage-live mulch. No-till-live mulch had 36.4% lesser energy requirement, 2.4 times more energy productivity than that under conventional tillage. Reduced tillage-live mulch and no-till-live mulch had higher water productivity compared to all other treatments. The conventional tillage had the highest net CO 2 -eq emission while no-till-live mulch had the lowest. Inclusion of cowpea as live mulch enhanced C sequestration which has the potential to offset approximately half of the total CO 2 emission, enhance energy use efficiency, land and water productivity. The findings of this study might be useful to develop a policy for sustainable high productivity through efficient resource use in the Eastern Himalayan Ecosystems that have the potential to become the corn belts of India. • Inclusion of cowpea live mulch under no-till (NT-LM) and reduced tillage (RT-LM) increased crop and land productivity. • The NT-LM/RT-LM increased energy use efficiency and crop productivity. • The NT-LM/RT-LM increased water productivity and decreased water footprint. • The NT-LM/RT-LM increased carbon sequestration and decreased carbon footprint. • The NT-LM/RT-LM decreased the cost of production and increased net profit. [ABSTRACT FROM AUTHOR]

• Cowpea as live mulch improves the productivity of intensified maize based system. • Live mulch based conservation tillage changes the soil carbon dynamics. • The NT-LM and RT-LM had higher CPI and CMI. • Soils of NT-LM and RT-LM had the maximum WHC and infiltration rate. The Sustainable Development Goals (SDGs) through agriculture, especially in the rainfed ecosystem, can be achieved by effective conservation management practices. Therefore, the study was conducted to test the hypothesis that the inclusion of intensified leguminous live mulch systems can improve system productivity, carbon management index (CMI), and soil health. Two cropping systems viz, summer maize-rainy season maize-lentil (SM-RM-L); and summer maize-rainy season maize-mustard (SM-RM-Ma) and five tillage and mulching practices such as 1) no-till (NT); 2) NT with live mulch (NT-LM); 3) reduced tillage (RT); 4) RT with live mulch (RT-LM); and 5) conventional tillage (CT) were tested in a split-plot design. Results revealed that yield attributes and yields of summer and rainy season maize, and cowpea were higher under SM-RM-L than the SM-RM-Ma cropping system. But in the winter, crop yields were higher under SM-RM-Ma than the SM-RM-L cropping system. NT-LM and RT-LM recorded 39.5 % and 48.4 % average higher grain yield of summer maize over the CT. The soil under the NT-LM had the maximum very labile C (2.32 g kg−1); the labile C fraction was the highest in soil under CT (1.72 g kg−1). The non-labile C fraction of soil organic carbon (SOC) was higher under NT and NT-LM than the rest of the tillage/mulch treatments in 0−10 cm depth. The soil under RT-LM had a higher lability index (LI,1.62) than the rest of the treatments in 0−10 cm depth. Conversely, in 10−20 cm depth, the soil under NT had higher LI (1.77) than the rest of the treatments. The soil under NT-LM and RT-LM had higher CPI and CMI than those in the rest of the treatments. Water holding capacity (WHC), infiltration rate, and cumulative infiltration were significantly higher under NT-LM and RT-LM than the other treatments. Thus, the study indicated the positive role of LM based conservation tillage practices in improving soil properties, carbon management indices, and productivity of maize-based cropping systems in the eastern Indian Himalayas. [ABSTRACT FROM AUTHOR]

Sustainability of conventional agricultural production systems is threatened by triple challenges of energy and environmental crises, deteriorating natural resources bases, and declining farm profitability. Current agricultural management practices (energy-intensive, inefficient external and natural input use, and crop biomass burning) are negatively impacting the ecosystem services which are the principal drivers for food security and human survival. Hence, there is a need to shift from unsustainable production practices to cleaner production systems. Energy use, carbon footprint (CF), and economic sustainability are important indicators of any clean production systems. Thus, a hypothesis was formulated that no-till (NT) cultivation along with mulching can provide an environmentally clean crop production practice that can enhance energy use efficiency, economic profitability, and reduce the CF. Therefore, the present experiment was conducted for four consecutive years (2012–15) to evaluate the energy budget, CF, and economics of NT along with bio-mulching for a cleaner upland rice production system. The experiment comprised of two tillage practices i.e. , conventional tillage (CT) and NT in main plots and four bio- mulches in subplots i.e. , rice straw mulch (RSM), Gliricidia sepium mulch (GLM), brown manuring mulch (BMM) of cowpea (Vigna unguiculata), and no mulch (NM) as a control. Results revealed that the adoption of NT curtailed energy use by 48.50%, specific energy by 49.63%, CF by 16.48%, and cost of cultivation by 35% in addition to enhancing energy use efficiency and benefit to cost ratio in comparison to CT. It was also observed that mulching, particularly the BMM, boosted the energy use efficiency, economic productivity, net returns, and benefit to cost ratio over NM. The results suggested that NT with BMM is an environmentally clean production technology to enhance the energy use efficiency, besides reducing the CF of direct-seeded upland rice production system in the Eastern Himalayas and similar eco-regions of the world. Image 1 • NTsystem reduced the cost of cultivation by 35% and increased net return by 12.8 times over CT. • Mulching in direct-seeded rice substantially increased net returns and B: C ratio than no mulch cultivation. • NT cultivation required 48.5% less energy and emitted 16.5% less GHGs in terms of CO 2 -e compared to CT. • Conversion of CT upland rice to NT and mulch based systems improves farmer's income and environmental quality. [ABSTRACT FROM AUTHOR]