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Reductions in soil productivity and soil water retention capacity, and water scarcity during crop growth, may occur due to long-term suboptimal tillage and fertilization practices. Therefore, the application of appropriate tillage (subsoiling) and fertilization (organic fertilizer) practices is important for improving soil structure, water conservation and soil productivity. We hypothesize that subsoiling tillage combined with organic fertilizer has a better effect than subsoiling or organic fertilizer alone. A field experiment in Henan, China, has been conducted since 2011 to explore the effects of subsoiling and organic fertilizer, in combination, on winter wheat (Triticum aestivum L.) farming. We studied the effects of conventional tillage (CT), subsoiling (S), organic fertilizer (OF), and organic fertilizer combined with subsoiling (S+OF) treatments on dry matter accumulation (DM), water consumption (ET), water use efficiency (WUE) at different growth stages, yield, and water production efficiency (WPE) of winter wheat over 3 years (2016–2017, 2017–2018, 2018–2019). We also analyzed the soil structure, soil organic carbon, soil microbial biomass carbon and nitrogen, and soil enzymes in 2019. The results indicate that compared with CT, the S, OF and S+OF treatments increased the proportion of >0.25 mm aggregates, and S+OF especially led to increased soil organic carbon, soil microbial biomass carbon and nitrogen, soil enzyme activity (sucrase, cellulose, and urease). S+OF treatment was most effective in reducing ET, and increasing DM and WUE during the entire growth period of wheat. S+OF treatment also increased the total dry matter accumulation (Total DM) and total water use efficiency (total WUE) by 18.6–32.0% and 36.6–42.7%, respectively, during these 3 years. Wheat yield and WPE under S+OF treatment increased by 11.6–28.6% and 26.8–43.6%, respectively, in these 3 years. Therefore, S+OF in combination was found to be superior to S or OF alone, which in turn yielded better results than the CT. [ABSTRACT FROM AUTHOR]

A land fallow system (LFS) designed to adjust the winter-wheat summer-maize cropping system to fallow summer-maize was introduced in Hebei Province to alleviate groundwater depletion in the region. However, some of the water saved was lost through evaporation from bare soil and transpiration by weeds. So far, no measurement has been done in the region to address this non-productive water loss, thereby limiting the water-saving potential of the introduced LFS. Furthermore, the reduction in crop production under the summer-maize – fallow system threatens food security. The objective of this study was to determine which practice is effective to keep soil water during fallow and the exact water-saving potential of different cropping system in the region. Firstly, field experiments were conducted under various soil surface management systems — including plastic mulching (PM), straw mulching (SM), shallow tillage (ST) and weed control (WC). The effects of saving water, controlling weeds and managing nutrients were analyzed under the various surface soil management methods. The results showed that compared with the control (no soil surface management, CK), 177, 64.7, 71.0 and 25.0 mm of water was saved respectively under PM, SM, WC and ST surface soil management methods in 2019–2020. The effect of weed control decreased in the order of PM > WC > SM > ST. While PM significantly increased soil nutrient in all the treatments, the others showed slight but insignificant increases. Secondly, the precise water-use of each of the cropping systems was determined using large lysimeters. The analysis showed that compared with the wheat-maize system, 60–100 mm of water was saved under alternating wheat-soybean, wheat-millet, mung bean – fresh edible maize, spring sweet potato cropping systems. The results were key for technical guide in developing future cultivation adjustment policies. • The maize-fallow system saved water 246 mm determined by large lysimeters. • Water-saving potential under various soil surface practice was analyzed during fallow. • Black film mulching proved to be the most effective practice during fallow. • Daily ET variation of different cropping systems was measured by large lysimeters. [ABSTRACT FROM AUTHOR]

In order to find out the appropriate measures for soil water preservation and wheat yield increase, a three–year field experiment was conducted in Yuzhou Experimental Station of Water Saving Agriculture in the west of Henan Province, China, during the growing seasons of 2014–2015, 2015–2016 and 2016–2017 to study the effects of different tillage modes and soil mulching measures on dynamics of soil moisture and temperature, photosynthetic characteristics and yield of winter wheat ( Triticum aestivum L .). The results showed that straw coverage and film mulching measures under the conventional tillage and no tillage modes increased soil moisture by 4.4%–27.3%,13.4%–41.8% and 6.2%–46.7%, 2.4%–80.2%, respectively. The treatments of soil surface coverage measures under both conventional tillage and no tillage modes at tillering stage increased the temperature of soil layer at 10 cm and 15 cm depth by 9.1%–18.2% and 10.0%–40.0% in 2014–2015, while mulching measures under the conventional tillage obviously increased soil temperature at wintering stage but decreased soil temperature at booting and mature stages in 2016–2017. However, mulching measures under no tillage mode reduced soil temperature in shallower layer during seedling establishment stage in the three–year period of 2014–2017. Moreover, the two mulching measures raised net photosynthetic rate (Pn) and water use efficiency (WUE) of functional leaves under the conventional tillage mode and reduced transpiration rate (Tr) at the filling stage. Except straw coverage measures under no tillage in 2015–2016, the combination of mulching measures under no tillage reduced Pn, Tr and WUE of wheat leaves at filling stage as compared to those without mulching measures. Under the conventional tillage mode, straw coverage increased wheat yield by 6.4%–9.3%, mainly due to the increase in the number of grains per panicle. Under no tillage mode, both straw coverage and mulching measures reduced wheat yield to different extents and film mulching measures was more effective than straw coverage. The combination of conventional tillage and straw mulching resulted in a yield of 8425.9–8888.9 kg hm −2 , so this combination was recommended as the optimal treatment under the conditions set in this study. [ABSTRACT FROM AUTHOR]

Abstract: Sustainable water use in the piedmont region of the Taihang Mountains in the northern part of the North China Plain (NCP) is under serious crisis due to the rapid depletion of groundwater caused mainly by pumping for agricultural irrigation. The development of water-conserving agricultural practices is essential in order to limit agricultural water use. To find an effective way to save water in the wheat-growing season without markedly reducing wheat yield, DSSAT-wheat was calibrated, validated and used to simulate water use by winter wheat. The simulations suggest: (1) since a moderately low growth in the leaf area index (LAI) of wheat does not result in low yield, moderate water deficits in March can save water, and therefore, the aim should be to avoid irrigation in March. (2) Depending on the soil water condition, irrigation in mid November is recommended to obtain a good growth of LAI and to create a moderate condition for water stress in March. (3) After the start of the growth of the ears (around 15 April), water deficits should be avoided so as to ensure there is no influence on ear growth and grain filling. Simulation of a 12-year period showed that when irrigation practice follows the above three principles, 76mm of evapotranspiration and 99.5mm irrigation water can be saved without much reduction in the yield of winter wheat (only 4.5%). This is sufficient to decrease the drawdown of groundwater by 0.42ma−1 and to improve water use efficiency from 1.27 to 1.45kgm−3. [Copyright &y& Elsevier]

Abstract: Improvement of water use efficiency (WUE) in crops is important for almost all agricultural practices around the world. Numerous studies have addressed WUE on a grain yield basis, but few on a photosynthesis basis and a biomass basis. Based on a 2-year field experiment (2002–2004), we analyzed wheat WUE not only on grain yield basis, but also on photosynthesis basis and biomass basis, and then discussed the effects of irrigation regimes on wheat WUE. We found that: (1) irrigation regimes had considerable effects on wheat transpiration, total evapotranspiration, and canopy temperature; (2) wheat WUE ranged 2.1–3.3μmolCO2/mmolH2O on a photosynthesis basis, 1.0–2.6kgm−3 and 1.1–2.1kgm−3 on a biomass and a grain yield basis, respectively. The maximum WUE appeared during the jointing and the milking stage, when suitable water management could be crucial to improve wheat WUE; (3) it was hypothesized by farmers and local water managers that more water supply over the conventional irrigation regime during the growing season could significantly increase both WUE and grain yield of the winter wheat in the north China plain (NCP). However, our results showed that with the increase of irrigation times and amount of irrigation water per growing season, wheat WUE was generally decreased and grain yield was not increased, although the evapotranspiration was significantly increased. Reduction in irrigation times and amount of irrigation water could be considered for saving water in the NCP; (4) WUE of winter wheat at photosynthesis and biomass levels were positively related with WUE at grain yield level. [Copyright &y& Elsevier]

Tillage combined with straw mulching is an effective water-saving agricultural strategy in eastern Central China. A two-year field experiment with four treatments, including conventional tillage (CT), conventional tillage with straw mulching (CT+S), no-tillage (NT) and no-tillage with straw mulching (NT+S), was conducted on semihydromorphic soil. The objective was to investigate how tillage with straw mulching affected the soil temperature, water consumption, photosynthetic rate (Pn), grain yield, soil temperature use efficiency (TUE) and water productivity (WP) in a winter wheat-summer maize rotation system. The results indicated that straw mulching tended to increase the soil temperature before the wheat regreening stage and decrease the soil temperature during the following wheat growing season and throughout the maize growing season. Compared with CT, the soil effective accumulated temperature (EAT) under the NT+S treatment significantly decreased by 4.8% but the annual ET increased by 4.3% in the winter wheat–summer maize rotation system. The Pn and transpiration rate (Tr) at the anthesis stage of wheat under the NT+S treatment increased by 15.2% and 15.6%, respectively, and the leaf water use efficiency (LWUE) during the growing season of maize increased by 11.3% as compared with that under CT treatment. Wheat yields decreased in the order of NT+S, NT, CT and CT+S during both experimental years, and the average yield of maize under the NT+S treatment increased by 27.2% compared with that under CT. Additionally, WP values under the NT+S treatment during both the wheat and maize seasons were 7.0% and 21.8% higher than those of the CT treatment (p < 0.05), respectively. The annual yield, TUE and WP values under the NT+S treatment were much higher than those under the other treatments. Therefore, NT+S treatment has a positive effect on yield and hydrothermal resource utilization in semihydromorphic soil in eastern Central China. • NT+S improved annual crop yield by 19.5% compared to conventional tillage. • NT+S increased hydrothermal resources utilization in this rotation system. • NT+S enhanced LWUE of the wheat and maize in eastern central China. [ABSTRACT FROM AUTHOR]

• Studying dynamics of soil water and nitrogen balance under conventional tillage versus conservation tillage by using RZWQM model. • Quantifying the winter wheat yield, water productivity and NUE under conventional tillage versus conservation tillage by using RZWQM model. • Establishing no-tillage as the optimum tillage to replace the conventional tillage for a sandy loam soil in Henan Province of China. The movement and distribution of the soil water and nitrogen are significantly influenced by tillage management. However, the dynamics of soil water and nitrogen due to changes in tillage and surface residue cover can be difficult to characterize due to limitations in field experimentation. The objective of this study was to quantify the differences in the soil water and nitrogen balance in the 0–100 cm soil profile, winter wheat (Triticum aestivum L.) yield, water productivity (WP) and nitrogen use efficiency (NUE) that occur when conventional tillage (CT) was changed to four types of conservation tillage treatments (no-tillage [NT], subsoiling tillage [ST], no-tillage with straw [NS] and subsoiling tillage with straw [SS]). Experimental data from 2011 to 2016 collected in Henan province, China on a sandy loam soil was used to calibrate and validate the Root Zone Water Quality Model (RZWQM2). Then the model was used to simulate four tillage systems (NT, NS, ST, SS) that were then compared with CT. The agreement index (d) between simulated and measured soil water content, soil nitrate concentration, and grain yield ranged between 0.71 and 0.93. The root means square error (RMSE) of the soil water content and nitrate concentration was in the range 0.02–0.03 cm cm−1and 5.5–10.3 mg kg−1, respectively. When CT was converted to NT from 2011 to 2016, the model simulated a 9.1 % reduction in annual water loss and a 55.6 % decrease in nitrogen leaching loss and simulated significant increase in average grain yield, WP and NUE. Replacing CT with NT appears to be the best of the four alternative conservation tillage conversion strategies in Henan Province of China. [ABSTRACT FROM AUTHOR]