Regulating Soil Temperature Research Articles

Influence of Spacing and Mulching on Strawberry (Fragaria x ananassa Duch.) cv. Sweet Charlie in Assam

Plant spacing and mulching material have effects on crop growth and yield as they play a vital role in conserving soil moisture, enhancing nutrient and moisture uptake, regulating soil temperature and reducing weed growth. Evident research gap exists on effects of spacing and mulching on growth and development of strawberry. Strawberry is a surface feeder crop, and hence, mulching plays a very important role in providing optimum conditions for root development. Therefore, a field experiment was conducted at the farmer’s field in Jorhat district of Assam, during 2019-20 and 2020-21 to study the effect of plant spacing and mulching on root volume of strawberry cv. Sweet Charlie. The experiment was laid out in a randomized block design with three replications based on 2 factors viz. plant spacing and mulch material. The trial consisted of a total of twenty treatments keeping five different plant spacing levels viz., 20 cm × 30 cm (S1), 30 cm × 30 cm (S2), 30 cm × 40 cm (S3), 40 cm × 40 cm (S4), 40 cm × 60 cm (S5) and four different mulching materials viz., paddy straw (M1), red mulch (M2), silver black mulch (M3) and no mulch (M4). Results revealed that 40 cm × 60 cm spacing under silver black mulch recorded maximum root volume which may have a positive impact on crop yield.

Effects of Cow-based Preparations and Mulching on Weed Management and Nodulation in Chickpea under Intercropping System

Mulching is one of agronomic practices with goals of lowering soil evaporation, preserving moisture, regulating soil temperature, inhibiting weed development, and enhancing microbial activity. It is mostly predicated on the recycling of biomass within the farm, with a focus on biomass mulching, the use of cow dung and urine preparations within the farm and preserving soil aeration. A field experiment was conducted for two years during the spring season (2019-20 and 2020-21) at Palampur, Himachal Pradesh (India), which comprises different combination of ghanjeevamrit (mixture of urine, dung, jaggery and chickpea flour), jeevamrit (mixture of urine, dung, jaggery, chickpea flour, handful soil, and water) and mulching (added at rate of 10 t ha-1). The weed count, weed dry matter, and yield of wheat as well as chickpeas were studied under sub-temperate humid zone (India). Data showed that application of cow-based preparations (ghanjeevamrit- added at rate of 0.5 t ha-1, jeevamrit-1st spray at rate 5%, 2nd spray 7.5% and subsequent sprays 10% jeevamrit in the water with the rate of 200 L acre-1 at 21 days interval) and mulching significantly affected weed count, dry matter, weed control efficiency and number of nodules of chickpea. Based on data of both years significantly lower weed count and dry weight at 120 DAS (before that weed count and dry weight was not affected significantly) was recorded in treatment T7(ghanjeevamrit + jeevamrit + mulching) which was statistically at par with T3 (mulching), T5 (ghanjeevamrit + mulching), T6 (jeevamrit + mulching) and T8 (control). At 150 DAS, significantly lower weed count was recorded in T5 which was at par with T3 and T6 and a significantly highest count was recorded in T4 (ghanjeevamrit + jeevamrit). At harvest, the highest weed count and dry weight of weed were found in treatment T2 (jeevamrit), T4, T1 (ghanjeevamrit), and T8. Similarly, the weed control efficiency was recorded numerically highest under T7 treatment. Minimum weed count and weed dry weight were found in the T7 treatment. Significantly highest nodule count in chickpea was recorded in T7 followed by T4, whereas the lowest was recorded in T8. Therefore, this study highlights the combined use of cow-based preparations with mulching to decrease weed count, dry matter as well as the number of nodules of chickpea increases under natural farming.

Restoration approach for alpine extremely degraded landscapes: testing direct seeding and mulching with grass clippings

Alpine meadows are key ecosystems that are facing increasing degradation due to climate change and anthropogenic disturbances. Despite tremendous efforts in ecological restoration and diverse communities rebuilding in alpine regions, restoration of extremely degraded alpine meadows (which have lost mattic epipedon) remains a major challenge for land managers. Here, we performed a field restoration experiment that combined seeding three grass species commonly (Elymus nutans, Poa annua, and Festuca sinensis) used in alpine meadow restoration with the application of grass clippings as mulch (bare land without mulching, 50% mulch cover, and 100% mulch cover) to ameliorate the soil surface conditions of degraded bare land. Soils covered with 50% and 100% mulching increased soil moisture, seedling density, plant cover, plant density, aboveground biomass, and belowground biomass, and reduced soil temperature during strong radiation days and insulated at night. In the three grass species seeding plots, mulching with grass clippings also improved seedling density, plant cover, plant density, and biomass. Moreover, 100% mulching had stronger restoration effect than 50% mulching. We further demonstrated that the improvement of surface microclimate in degraded alpine meadows by grass clipping mulching, that is, increasing soil moisture and regulating soil temperature, is an important reason for the success of grassland restoration. Mulching with grass clippings simulates the original mattic epipedon, improving the surface hydrothermal conditions and promoting ecological restoration facilitation. We encourage the application of locally available grass clippings after seeding as this can be an efficient, low‐cost, and sustainable approach for restoring extremely degraded high‐elevation alpine grassland ecosystems.

Optimized Farmland Mulching Improves Rainfed Maize Productivity by Regulating Soil Temperature and Phenology on the Loess Plateau in China

Owing to global warming, continuously increasing the grain yield of rainfed maize is challenging on the Loess Plateau in China. Plastic film mulching has been extensively utilized in dryland agriculture on the Loess Plateau. However, higher topsoil temperatures under film mulch caused rainfed-maize premature senescence and yield loss. Here, we aimed to explore the influence of topsoil temperature driven by novel double mulching patterns on rainfed maize productivity based on the excellent moisture conservation function of plastic film. A maize field experiment was conducted in two different areas, namely Changwu, a typical semi-arid area, and Yangling, a dry semi-humid area. The experiment followed a randomized block design with three replications. Five flat-planting practices were examined in 2021 and 2022: (1) bare land (CK), (2) transparent film mulching (PFM), (3) black film mulching (BFM), (4) double mulching of PFM with a black polyethylene net (PFM + BN), and (5) double mulching of PFM with whole maize stalks (PFM + ST). Soil hydrothermal conditions, maize growth dynamics, grain yield, water use efficiency (WUE), and economic returns were quantified under different mulching practices. Under double mulching treatments, topsoil temperatures were lower than PFM by 1.7–2.0 °C at the two sites (p < 0.05), whereas BFM was slightly lower than that of PFM by 0.6–0.7 °C at Yangling (p > 0.05). The average growth period for maize under double mulching was longer than that under PFM by 8–11 days at the two sites. Double mulching treatments significantly improved the leaf area index (LAI), chlorophyll relative content (SPAD), and aboveground biomass compared to CK and PFM during the late growth stage. Compared with PFM, average grain yield increased by 14.93%, 18.46%, and 16.45% in Changwu (p < 0.05) under BFM, PFM + BN, and PFM + ST, respectively, and by 2.71%, 24.55%, and 20.38% in Yangling. The corresponding WUEs also increased. Additionally, net income under BFM was higher than that under other treatments, and there were no significant (p > 0.05) differences between PFM + ST and BFM in Changwu. However, PFM + ST in net income averaged 10.72–52.22% higher than other treatments, and its output value was 19.51% higher in Yangling. In summary, smallholder farmers can adopt PFM + ST to improve rainfed-maize productivity in the Loess Plateau in China.

Bryophytes dominate plant regulation of soil microclimate in alpine grasslands

Soil temperature and moisture are important regulators of a broad range of biotic and abiotic processes in terrestrial ecosystems. Vegetation can, in turn, play a role in regulating soil microclimate, which creates potential for powerful and interactive feedbacks from soil and vegetation on the atmosphere. Although the regulatory effect of vegetation on soil microclimatic conditions has been quite extensively and empirically assessed, most studies have determined the net effect of intact woody vegetation versus bare ground. However, for other plant functional groups we lack a clear understanding of their role and any climate‐context dependency in controlling microclimatic conditions.We investigated the role of three major plant functional groups – graminoids, forbs and bryophytes – in regulating soil microclimate in semi‐natural alpine grasslands. Using a fully factorial above‐ground biomass removal experiment, we assessed the role of these plant functional groups in regulating soil temperature amplitude, soil moisture, and number of freezing days. The experiment was replicated across orthogonal temperature and precipitation gradients in Norway to assess whether the effects of functional group abundance varied with climate.The effect of plant biomass on soil microclimate varied among functional groups across the climatic gradients. Bryophytes reduced growing season soil temperature, whereas graminoids and forbs did not (0.5ºC compared to 0ºC), and with a stronger effect in colder climates at higher elevations and on days with high solar radiation. Bryophyte biomass further reduced the number of soil freezing days at boreal and sub‐alpine sites. Finally, graminoid biomass partly explained variation in soil moisture: soils dried more under graminoids at drier sites.Our findings highlight that functional group identity plays a key role in regulating soil microclimate in alpine grasslands across seasons. The strong effect of bryophytes on soil temperature points to their importance in the plant community for a variety of ecosystem functions, some of which may be indirectly vulnerable to future warming via biomass reductions of bryophytes.

Effects of phase change material inclusion on reducing greenhouse gas emissions from soil in cold region.

Increased gas emissions from soil into the atmosphere are one form of ecosystem feedback in response to climate change. Soil temperature plays a critical role in the soil emission of carbon dioxide (CO2) and nitrous oxide (N2O) suggesting that the release of gases can be reduced by regulating soil temperature. This study proposes a green microencapsulated phase-change material (mPCM) as a soil temperature regulator due to its ability to absorb and release heat during temperature phase transition. The objective is to test how mPCM in soil mixtures influences CO2 and N2O fluxes under laboratory-controlled conditions. For this purpose, a series of soil incubations were carried out with different temperature regimes and soil moisture. The test results revealed that at 20% soil moisture mPCM reduced cumulative CO2 emissions from the soil by 16.4% during the thawing stage and by 20.5% during the freezing stage. At 25% soil moisture, mPCM showed a greater effect reducing cumulative CO2 emissions by 23.9% during the thawing stage and by 24.2% during the freezing stage. At below-zero temperatures, mPCM reduced the total N2O flux by 11.6% at 20% soil moisture and by 26.0% at 25% soil moisture, compared to soil without mPCM. As soil moisture increased, the effects of mPCM on CO2 and N2O fluxes became more pronounced. Cyclic freezing and thawing of soil led to an increase in gas flux. This variation was reduced by the mPCM due to its ability to mitigate the change of soil temperature. Inhibition of the rise in soil temperature due to the inclusion of mPCM reduced the rate of activation of soil mineralization, which reduced gas fluxes. This study demonstrates the potential of mPCM application to reduce greenhouse gas emissions from soil through thermoregulation.

Wind mediates the responses of net ecosystem carbon balance to climatic change in a temperate semiarid steppe of Northern China

As an important carbon sink to mitigate global climate change, the role of arid and semiarid grassland ecosystem has been widely reported. Precipitation and temperature changes have a dramatic impact on the carbon balance. However, the study of wind speed has long been neglected. Intuitively, wind speed regulates the carbon balance of grassland ecosystems by affecting the opening of vegetation stomata as well as near-surface moisture and temperature. It is sufficient that there is a need to conduct field observations to explore the effect of wind speed on the carbon balance in arid and semiarid grassland. Therefore, we conducted observations of carbon fluxes and corresponding climate factors using an eddy covariance system in a typical steppe in Inner Mongolia from 2017 to 2021. The research contents include that, (i) we depicted the changing patterns of carbon fluxes and climate factors at multiple time scales; (ii) we simulated the net ecosystem carbon balance (NECB) based rectangular hyperbolic model and compared it with the observed net ecosystem exchange values; (iii) we quantified the mediated effect of wind speed on NECB by adopting structural equation modeling; (iv) we used the constrained line method to explore what wind speed intervals might have the greatest carbon sequestration capacity of vegetation. The results were as follows, (i) the values of NECB for the five years of the study period were 101.95, −48.21, −52.57, −67.78, and −30.00 g C m−2 yr−1, respectively; (ii) if we exclude the inorganic carbon component of the ecosystem, we would underestimate the annual carbon balance by 41.25, 2.36, 20.59, 22.06 and 43.94 g C m−2 yr−1; (iii) the daytime wind speed during the growing season mainly influenced the NECB of the ecosystem by regulating soil temperature and vapor pressure deficit, with a contribution rate as high as 0.41; (iv) the grassland ecosystem had the most robust carbon sequestration capacity of 4.75 μmol m−2 s−1 when the wind speed was 2–3 m s−1. This study demonstrated the significant implications of wind speed variations on grassland ecosystems.

Influences of Paraffin-Based Phase Change Material on Soil Engineering Properties

Paraffin-based phase change materials (PPCMs) have been recognized as a potential tool to regulate soil temperature and reduce the freeze–thaw impact on soil. However, as a new filling material for geotechnical structures, such as dam core walls, the engineering applicability of PPCM-mixed soil (PS) needs to be further studied. In this paper, the influences of PPCM on the soil engineering properties (i.e., compaction characteristics, consolidation properties, mechanical behaviors, and permeability) and the PPCM leakage behavior were studied through a series of laboratory experiments. The results showed that the addition of PPCM results in an obvious decrease in the maximum dry density and optimum water content, a slight change in the compression coefficient, a significant reduction of the plasticity and cohesion, and an enhancement of the friction angle and impermeability. In addition, the PPCM in PS specimens will leak under the constant hydraulic gradient or vacuum saturation, and the leaked mass is positively related to the initial PPCM content. The PS specimens after 64-day seepage will still have a good impermeability. This paper is an important prerequisite for the practical applications of PS and provides a basis for its performance improvement.

Excessive Nitrate Limits the Sustainability of Deep Compost Mulch in Organic Market Gardening

Market gardening is a widespread practice of bio-intensive vegetable production characterized by direct marketing, small-scale farming structures, high crop densities, and innovative cultivation approaches. Currently, deep compost mulch (DCM) is a popular trend among related growing techniques. The combination of no-till and a permanent mulch of compost aims to improve soil fertility, regulate soil temperature, retain soil moisture, and control weeds. To address the problem of perennial weeds in organic no-till, deep mulch layers of typically 150 mm are used. The amount of compost required and the associated N inputs are immense and carry the risk of environmentally harmful N surpluses that can be lost through nitrate leaching or denitrification. The aim of this study is to evaluate the use of compost as mulch and to investigate N dynamics under DCM. For this purpose, a literature review was conducted, and soil inorganic nitrogen (Nmin-N) was measured under on-farm conditions up to a soil depth of 900 mm in a market garden with DCM in Germany for one year. Furthermore, based on the collected data, the different N pathways were calculated using the N-Expert and NDICEA models and simulated for two additional scenarios. Results from field measurements showed a strongly increased N-surplus not taken up by the crops and a shift of Nmin-N to deeper soil layers for municipal organic waste compost (MW), with an average accumulation of 466 kg Nmin-N ha−1 at 600–900 mm depth. N inputs from DCM can be significantly reduced by the use of green waste compost (GW) with low bulk density or wood waste compost (WW) with an additional high C/N ratio.

Effects of planting patterns plastic film mulching on soil temperature, moisture, functional bacteria and yield of winter wheat in the Loess Plateau of China

Effects of planting patterns plastic film mulching on soil temperature, moisture, functional bacteria and yield of winter wheat in the Loess Plateau of China

No-tillage with straw mulching promotes wheat production via regulating soil drying-wetting status and reducing soil-air temperature variation at arid regions

No-tillage with straw mulching promotes wheat production via regulating soil drying-wetting status and reducing soil-air temperature variation at arid regions

Mulching improves strawberry fruit growth and yield by regulating soil temperature and soil moisture in humid tropical India

Production and quality of strawberry (Fragaria × ananassa, Duch.) fruits are significantly reduced in conventional farming methods in humid tropical India. Little information exists on the effect of mulching and its mechanisms regulating environmental factors, physiological processes as well as biochemical constituents to improve its yield and quality. Here, the effects of different coloured plastic mulches (black, transparent, and red) and organic mulches (paddy straw, banana leaves and weeds) were tested on the yield and quality of strawberries. Black plastic mulches had a large impact on fruit weight, size, and phytochemical content. The mean fruit yield with black plastic mulching was 68% greater than the control. Black polythene mulching adjusted environmental factors and physiological processes to boost productivity and quality of strawberry fruits and hence could be recommended in humid tropical regions.

Effects of Living Mulch and Branches Mulching on Soil Moisture, Temperature and Growth of Rain-Fed Jujube Trees.

The influence of different mulching measures on soil moisture, soil temperature, and crop growth was investigated during the jujube growing season in rain-fed jujube orchards using micro-plot experiments. The mulching treatments included clean tillage (CT, control treatment), jujube branches mulching (JBM), and white clover planting (WCP). The results revealed that: (1) The average soil moisture content of JBM was greater than that of CT by 3.76% and 2.34%, respectively, during the 2013 and 2014 jujube growth periods, and its soil water deficit was minimal in each soil layer from 0 to 70 cm. WCP had the greatest soil water deficit. The average soil moisture content of the 0–70 cm soil layer in WCP was 3.88% and 5.55% lower than that in CT during the 2013 and 2014 jujube growth seasons, respectively (p < 0.05). (2) JBM had the highest annual average soil moisture content in each soil layer from 0 to 70 cm, followed by CT, while WCP had the lowest. White clover and jujube competed for water in the 20–40 cm soil layer, and JBM had the lowest variation in soil moisture. (3) Mulching with jujube branches and planting white clover could both control the temperature of the 0–25 cm soil layer and narrow the daily temperature range, with JBM being the least affected by air temperature. (4) Jujube’s leaf area index and stem diameter increase in JBM were both significantly greater than in CT and WCP. In conclusion, using pruned jujube branches as surface mulch is appropriate for rain-fed jujube orchards because it can preserve soil moisture, regulate soil temperature, and promote jujube growth.

Effects of soil mulching on staple crop yield and greenhouse gas emissions in China: A meta-analysis

Food security and global warming in the 21st century are two major challenges for agricultural development. Soil mulching either with plastic film or straw is a common agricultural practice, which can improve crop growth by reducing evaporation and regulating soil temperature, and is widely applied globally. Although soil mulching can significantly affect crop yield and greenhouse gas (GHG) emissions, there is controversy regarding its effect on crop yield and GHG emissions in the long run. We conducted a meta-analysis to explore the impact of soil mulching practices on maize, wheat, and rice yield and GHG emissions in China. Our results demonstrated that soil mulching improved crop yield (16 – 22%), and its impact on GHG emissions varied with crop, region, and mulching method. Plastic film mulching (FM) and straw mulching (SM) increased yield by 28% and 9% compared with no-mulching (NM), respectively. FM decreased methane (CH4) emissions in paddy by 51%, and CH4 uptakes in upland by 23%, but SM increased CH4 emissions in paddy by 140%. Soil mulching increased carbon dioxide (CO2) emissions of maize and wheat by 13% and 12% than NM, respectively. CO2 emissions under FM decreased when ATP > 911.8 mm and AMT > 15.6 °C. N2O emissions under soil mulching may be reduced when nitrogen input is greater than 144 kg N ha−1. This showed that the reasonable use of soil mulching has the potential to achieve a win-win strategy to ensure food security and mitigate climate change.

Role of Mulching in Regulating Soil Temperature after Five Cycles of Tillage Treatments in a Rice-Wheat System

Role of Mulching in Regulating Soil Temperature after Five Cycles of Tillage Treatments in a Rice-Wheat System

The possible positive effect of white bean intercropped with saffron under glycine betaine application and limited moisture

• Increasing irrigation intervals resulted in higher soil temperatures. • Glycine betaine had an inhibitory effect against temperature stress. • Saffron + white bean intercrop reduced soil temperature compared to pure saffron. The saffron dormancy period begins after drying above-ground parts, including actual and apparent phases. The differentiating reproductive organs during apparent dormancy need to be induced under optimal temperature conditions, while saffron farms are free of vegetation after the drying phase. Covering the soil surface during the summer season may be advantageous to counter such a major constraint. The current study was conducted at the experimental station of the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, from 2018-to 2019 and repeated from 2019-to 2020. A split-split plot arranged in a randomized complete block design with three replicates was used. Limited moisture of white bean (10 d irrigation as lower interval and 20 d irrigation as higher interval), glycine betaine foliar application (0 and 10 mM), and planting patterns (sole saffron, sole white bean, and saffron + white bean intercrop) were considered as the main plot, subplot, and sub-sub plot, respectively. Higher irrigation intervals resulted in increased soil temperatures, while glycine betaine had an inhibitory effect against heat stress. The Saffron flower number significantly improved after applying 10 mM glycine betaine. Furthermore, the maximum middle- (5–10 g) and large-sized (> 10 g) daughter corms and land equivalent ratio were recorded when 10 mM glycine betaine was applied in saffron + white bean intercrop. A similar response was also recorded in N and P concentration in the middle- and large-sized daughter corms. Considering the water restriction in arid and semi-arid areas, saffron-white bean intercropping, concurrent with 10 mM glycine betaine application, can play a pivotal role in regulating soil temperature and increasing land equivalent ratio.

Effect of mulching, row direction and spacing on microclimate and wheat yield at Ludhiana

The field experiments were conducted in rabi seasons of 2014-15 and 2015-16 at research farm, Ludhiana, Punjab. Wheat variety (WH 1105) was sown in two row directions viz, east-west (E-W) and north-south (N-S) with three row spacing as S1 (15 cm), S2 (22.5 cm) and S3 (30 cm), and two mulching levels viz., Mo (No mulch) and M1 (mulch at the rate of 5t ha-1). PAR interception, canopy temperature, soil temperature and soil moisture were recorded periodically during the crop season in all the treatments. The results revealed that the intercepted photosynthetically active radiation (PAR) was 4- 5 per cent higher in E-W than N-S row direction which contributed 1.67 q ha-1 higher grain yield. Better utilization of solar radiation was observed in 15.0 cm row spacing and the canopy temperature was 0.5°C higher in unmulched crop as compared to mulched crop during both years. Straw mulching @ 5t ha-1 improved soil moisture and regulated soil temperature. Mean soil temperature was higher (1.0 ºC) under mulched crop as compared to unmulched crop. The soil moisture was 4-5 per cent higher under mulched crop as compared to unmulched crop which ultimately resulted in higher soil temperature during early growth stages. Significantly higher grain yield was recorded in mulched crop as compared to unmulched.

Effects of in situ freeze-thaw cycles on winter soil respiration in mid-temperate plantation forests

As an important factor regulating soil carbon cycle, freeze-thaw cycle significantly affects winter soil respiration in temperate regions. However, few in situ studies have been carried out to evaluate the effect of freeze-thaw cycle on soil respiration. Here, a field experiment was conducted to explore the response of winter soil respiration to freeze-thaw cycle and the underlying mechanisms in larch and Chinese pine plantation forests in a mid-temperate region. These results indicated that CO2 emissions during the freeze-thaw period accounted for 18.89-18.94% and 0.79-1.00% of the cumulative winter CO2 emissions and the annual soil CO2 emissions, respectively. Soil respiration rates during the thawing phase were 1.54-3.95 times higher than those during the freezing phase, which was mainly due to the increase of soil microbial biomass upon thawing. This effect declined during the second freeze-thaw cycle compared to the first freeze-thaw cycle due to the exhaustion of resources for microbes. The different responses of soil CO2 flux to freeze-thaw cycle between the two types of forests were mainly because of the difference in the thickness of litter layer, which plays an important role in regulating soil temperature and enzyme activity. These results suggest the intensity and frequency of freeze-thaw cycle strongly affect soil carbon emissions during the freeze-thaw cycle period. Therefore, these factors should be considered in laboratory studies and model simulations under climate change scenarios.

Tillage effects on soil properties and crop yield after land reclamation

Tillage treatments have an important effect on soil microstructure characteristics, water thermal properties and nutrients, but little is known in the newly reclaimed cultivated land. For the reason, a long-term field study was to evaluate the tillage effects on soil physicochemical properties and crop yield in newly reclaimed cultivated land via the macroscopic and microscopic analysis. Three tillage treatments were tested: continuous conventional moldboard plow tillage (CT), sub-soiling/moldboard-tillage/sub-soiling tillage (ST) and no-tillage/sub-soiling/no-tillage (NT). Under CT, the microstructure was dominated by weakly separated plates structure and showed highest bulk density (BD) (1.49 g cm−3) and lowest soil organic matter (SOM) (3.68 g kg−1). In addition, CT reduced the capacity of soil moisture retention and temperature maintenance, resulting in aggregate structure deterioration and fragility. Unlike CT, the soil was characterized by moderately separated granular structure and highly separated aggregate structure under conservation tillage practice of ST and NT. NT was associated with the highest soil moisture content (20.42%), highest quantity of macroaggregates (> 0.25 mm) by wet-sieving (34.07%), and highest SOM (6.48 g kg−1) in the surface layer. Besides, NT was better able to regulate soil temperature and improved the values of geometric mean diameter. Under NT and ST, a stable soil structure with compound aggregates and pores was formed, and the maize yield was increased by 12.9% and 14.9% compared with CT, up to 8512.6 kg ha−1 and 8740.9 kg ha−1, respectively. These results demonstrated the positive effects of NT and ST on soil quality and crop yield in newly reclaimed cultivated land.

No-tillage with mulching improves maize yield in dryland farming through regulating soil temperature, water and nitrate-N

• Reduced nitrate leaching under no-till with mulching and biochar in dryland farming. • No-till with mulching increased soil water content in dryland farming. • Long-term continuous NSP and NP was effective in increasing yield. • NSP was the optimal patterns for conservation agricultural system in dryland farming. Nitrogen (N) losses from cropland soils contribute to a series of ecological problems. No-tillage and mulching are widely regarded as practices that can minimize the disturbance of the agro-ecosystem and regulate the water cycle in dryland farming. However, detailed understanding of water and nitrate-N transport in soil and their effects on the soil ecosystem under no-tillage with mulching is lacking. To improve our understanding, a long-term continuous maize field experiment was conducted in the southern Loess Plateau, China. This article reports experimental data form a complete growth year for spring-sowing maize, including the fallow period (from October 2017 to April 2018) and the growth period (from May 2018 to September 2018) after 15 years maize planting. Treatments included conventional tillage (CT), no-tillage (NT), no-tillage with biochar (NB), no-tillage with straw mulching (NS), no-tillage with plastic film mulching (NP), and no-tillage with straw-plastic film mulching (NSP). Overall, the results revealed that the effect of different treatments on soil temperature gradually weakened with increased maize growth and increased soil depth. The NP had the highest average temperature during the whole growth period, and NS had the lowest. Average soil profile water content (SWC) and the soil water storage (SWS) of the mulching treatments (NSP, NP, NS) were higher than the non-mulching (CT, NT, NB) at each stage. The SWS of NSP in the maturity period was significantly greater by 7.1 % compared with CT. Our results indicated that there was no nitrate-N leaching in NSP and NP below 40 cm, and the nitrate-N accumulation followed the order of CT > NT > NS > NB > NP > NSP. Conventional tillage exhibited a nitrate-N accumulation peak in deep soil layers (140−180 cm), while nitrate-N peaks of the NT, NS, and NB treatments in the shallow soil layers (40−90 cm) decreased with seasonal variation. However, the NSP and NP increased yields by 36.5 % and 34.1 %, NT decreased yields by 14.8 %, respectively, compared to CT. These suggest that no-tillage alone (NT) does not effectively improve soil water use efficiency and may even reduce yields, but reduce nitrate leaching. No-tillage with straw-plastic film mulching (NSP) was the most effective measure to facilitate the sustainable development of agriculture in dryland farming.