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The mechanism of plastic film mulching combined with ridge-furrow construction to stimulate the soil water variation and then to promote the photosynthesis and resource utilization of maize are unclear. Unfortunately, this mechanism forms the scientific basis for optimizing the mulching design. A field experiment was conducted in a semi-arid region of China in 2015 and 2016 to evaluate the effects of plastic film mulching and ridge-furrow construction on soil hydrothermal conditions, photosynthetic characteristics, maize yield and resource use efficiency. Four treatments were established: ridge-furrow construction with full plastic film mulching (RF), ridge-furrow construction with half plastic film mulching (RH), flat planting with half plastic film mulching (FH), and traditional flat planting with no plastic film mulching (CK). Our results showed that plastic film mulching significantly improved soil water content and temperature, thereby enhancing the photosynthetic rate (Pn) of maize mainly by facilitating stomatal opening. The thermal effect of mulching accelerated maize growth and indirectly promoted water utilization, resulting in marked soil wet-dry alternation. This alteration was more obvious in 20–120 cm soil profile, which was characterized by relatively wet within 50 days after sowing (DAS), relatively dry from 50 to 130 DAS, and relatively wet again after 130 DAS, in comparison with that without mulching (CK). This intense soil moisture transform between wetting and drying was indicative of an efficient water use strategy because it drives water from soil evaporation to crop transpiration, thereby improving photosynthesis and plant resource capture. Results suggested the RF treatment, driving intense wet and moderate dry in soil relative to RH (moderate wet and slight dry) and FH (slight wet and intense dry), is an efficient farming strategy, which improved maize grain yield by 21.1–92.3%, radiation use efficiency (RUE) by 15.5–66.2%, water use efficiency (WUE) by 27.4–87.4%, and nitrogen use efficiency (NUE) by 15.4–37.8% based on grain yield than the other treatments. Therefore, the soil wet-dry alternation behavior (especially in 20–120 cm soil profile) during growth period can be used as a reference evaluation indicator for mulched maize utilization of resource in semi-arid regions.

Wheat (Triticum aestivum) is grown in a wide range of water regimes and produces both grain and forage in the U.S. Southern Great Plains (SGP). Despite being relatively adapted to water stress, decreased water supply has become the main abiotic factor limiting wheat yield in the region. A 5-yr field study was conducted to investigate the yield determination in winter wheat under a center pivot irrigation system. Twenty elite wheat cultivars were grown at four water regimes, I100, I75, I65, and I50 to meet 100%, 75%, 65%, and 50% evapotranspiration (ET) requirement, respectively. The 2011 and 2013 seasons had all irrigation levels, while there were only two irrigation levels in 2012 (I50 and I65) and 2014 (I75 and I100), and three irrigation levels in 2015 (I50, I75, and I100). In most seasons, ET, biomass, and grain yield decreased consistently from higher to lower water regime, but water use efficiency (WUE) and harvest index (HI) were the highest at I75. Averaged across all years and genotypes, grain yield was reduced by only 5% from I100 to I75 indicating that reducing irrigation to meet 75% of ET requirement can still achieve similar yield to I100 and maximize HI and WUE. Newer cultivars including Duster, Endurance, Winterhawk, TAM 112, and TAM 113 had greater yield at I50 compared to other cultivars. Grain yield showed a strong relationship with biomass, HI, and ET. At lower water regimes (I50, I65), all three yield components (spikes per square meter, seeds per spike, and kernel weight) were correlated to grain yield. At higher water regimes (I75 and I100) grain yield was consistently related to kernel weight. This study demonstrated that high yield can be achieved at an irrigation level of I75. In addition, planting newer drought tolerant cultivars may provide yield benefits under water-limited conditions in the SGP.

Utilizing the ridge- furrow mulching system with plastic film (RFMS) is an effective strategy for improving crop productivity in semiarid areas. However, the key mechanism by which RFMS drives spatiotemporal hydrothermal variation of soil to positively affect crop production is not well-defined, and a better understanding of this mechanism could guide RFMS optimization. A two-year field experiment was conducted with three planting treatments: 1) the RFMS with high coverage ratio, 50 cm mulched ridge:10 cm bare furrow, RFH; 2) the RFMS with low coverage ratio, 60 cm mulched ridge:60 cm bare furrow, RFL; and 3) flat planting without mulching as the control treatment, CK. The results showed that RFMS increased topsoil temperature by 1.0–2.5 °C during the day (08:00–20:00) and 1.6–3.4 °C at night (20:00–08:00), respectively, compared with CK, which led to a decrease of 0.4–1.3 °C in diurnal temperature amplitude, but indicated a strong positive impact on maize growth in the thermally deficient study area. In addition, RFMS drove the spatio-temporal alternation of soil wetting and drying (alternation of high and low SWC) relative to CK, indicating an efficient water use strategy that significantly reduces soil evaporation but promotes the plant transpiration during water sensitive period. These effects in RFH were significantly greater than those in RFL due to its significantly enhanced water infiltration, suppressed evaporation and reduced heat loss, which stimulated vigorous crop growth. This study suggested that, compared to CK, RFH was more efficient than RFL to improve maize production, which increased these amplitudes from 43.1% to 59.2% in grain yield increase, from 38.5% to 57.4% in water use efficiency (WUE) increase and from 71.7% to 95.0% in economic benefit increase, respectively. Therefore RFH can be considered as a superior technique for overcoming simultaneous drought and cold stresses in northwestern China.

Pakistan faces significant future challenges to feed a growing population, with 47% of the population currently categorised as food insecure. The rice-wheat (RW) zone of Punjab is the major aromatic rice producing area of Pakistan. Here the rice-wheat cropping rotation is practiced over a variety of soils under a range of agronomic and irrigation practices. It is important to quantify and understand the existing crop yield gaps and associated factors in this zone to identify opportunities for gap-reduction leading to increased land and water productivity and sustainable water use in Pakistan. The APSIM model was parameterised for local soils and climate, and then calibrated for rice and wheat growth, phenology and yields using experimental data sets. The model calibration was then validated using 5-year (2009–2014) farmer grain yield records from each of the highest (Gujranwala) and lowest (Narowal) performing districts in Punjab, before being used to simulate long-term (34 years) rice-wheat yields for current farmer practices and also for potential (no water or N-stress) production, in both districts. The revealed yield gaps were further assessed as a function of sowing date. Observed and simulated farmer R–W yields for Gujranwala were greater than those for Narowal; however potential yields were similar at both sites (for both rice and wheat). Farmers currently achieve only around 36% (Narowal) to 67% (Gujranwala) of potential yield for rice, and 48–56% of potential for wheat (Narowal and Gujranwala respectively). The modelling analysis of abiotic stresses under which the farmers’ crops were grown revealed that nitrogen (N) deficiency was the primary driver for the large yield gaps at both sites, for both crops, with low topsoil carbon (0.19% Narowal; 0.49% Gujranwala). The simulated farmer crops were not significantly constrained by water limitations under the current N application rates, or by high/low temperatures. Gaining a better understanding of farmers’ reasons for low N-rates is important – it could be related to (non-modelled) soil micronutrient constraints or risk aversion associated with irrigation water supply reliability. Current sowing dates are also problematic for the existing varieties, with optimum rice sowing dates being up to one month later than the current ones, yet optimum wheat sowing dates being a month (or more) earlier than current ones. This wicked problem points towards the need for further investigations into system optimisation, with better nutrient management, increased soil carbon levels, and shorter season high-yielding rice varieties likely to be key elements.

To examine the combined effects of planting models with nutrient management strategies on grain filling rates, productivity, soil water storage, water-use efficiency and economic benefit of rain-fed corn, there for a field research was carried out during 2015–2016 in a semi-arid region of China. Three planting models were tested: ridge furrow system with plastic mulching (M1), furrow planting with soil crust ridges (M2), and flat planting without plastic mulching (M3); in combination with four nitrogen levels: 0 kg ha–1 (N0); 100 kg ha–1 (N1); 200 kg ha–1 (N2), and 300 kg ha–1 (N3). We found that M1 planting model with higher 300 kg-1 N ha-1 could significantly increase soil water availability at different growth stages, as a result significantly increased WUE (56.6%), RUE (71.2%), ET (8.8%), soil water storage, biomass (35.5%), and grain yield (70.8%) of rain-fed maize than that of M3N0 treatment. Increasing the nitrogen level as a result significantly increased the economic benefit, yields and yield components of rain-fed maize under different planting models, but AEN shows a significantly decreasing trend. The M1N3 treatment significantly promoted the LAI and grains filling of the basal, middle and upper seeds than that of M2 and M3 cultivation models with the highest nitrogen level. The M1N3 treatment obtained the highest (12,775 CNY ha-1) net profit, improved the SWS throughout the grain-filling duration, which resulted in higher productivity. Thus, M1N3 treatment can be used to improving productivity, economic benefit, and water use in semi-arid areas.

Improved management practices are necessary to increase grain yield and water-use efficiency of rainfed winter wheat in semiarid environments. Yield and its components, evapotranspiration, and accumulation and apparent remobilisation of stem water soluble carbohydrates (WSC) were measured to understand the effects of root pruning and its interactions with seeding rate, water and nitrogen supply. Two factorial studies under straw mulching with continuous wheat were established in the Loess Plateau of China. Study 1 was repeated over four seasons and included six treatments from the combination of three root treatments, i.e. root pruning in winter before dormancy (RPw), root pruning at the re-green stage in spring (RPs) and untreated control (CK), and two seeding rates. Study 2 was repeated over three seasons and included twelve treatments from the combination of two root treatments (RPs and CK), two nitrogen rates and three pre-sowing soil water levels. Yield ranged from 2571 to 7722 kg ha−1, harvest index from 0.28 to 0.56, and water-use efficiency from 5 to 20 kg ha−1 mm−1. Root pruning improved grain yield, harvest index and water-use efficiency by 6–11% across environmental conditions. Grain yield increased more (i) by pruning roots in spring than in winter, (ii) in high plant density than in low plant density crops, and (iii) in low-yielding conditions. It is concluded that spring root pruning is a viable option to improve wheat yield and water use efficiency under straw mulching in semiarid environment.

Rice in eastern India is widely cultivated using conventional management practices, including puddled transplanting (PTR) for crop establishment, which are water and energy intensive. To conserve water and maximise its efficient use, improved crop management practices must be identified which are feasible and attractive to farmers. These improved practices include dry direct seeding of rice (dDSR), improved medium-duration rice varieties and alternate wetting and drying (AWD) irrigation management. These have separately been shown to reduce the irrigation water requirement for rice cultivation while maintaining yields similar to those of traditional high yielding long-duration varieties. We conducted a field experiment over two rice-growing seasons to examine the effects on rice grain yield and water productivity of layering these improved management practices, compared to conventional PTR with traditional long-duration rice. We also assessed the usefulness of simple perforated tubes to implement AWD management in the field. dDSR reduced rice grain yield by 3–6% while requiring 23% less irrigation water over PTR. The medium-duration hybrid rice variety produced 2–4% higher grain yield under direct seeding while using 4–5% less irrigation water than the long-duration variety. AWD reduced irrigation water use by 26–52% but also reduced grain yield by 3–14%. Water use efficiency was improved by dDSR, AWD and by using medium-duration hybrid variety. Combining all three management practices reduced irrigation water use by an average of 18% while improving irrigation water productivity by 21%, without significant reduction in grain yield under shallow AWD of 10 cm depth in dDSR and upto 15 cm depth for PTR. This combination is a novel approach to sustainably improve farmers’ rice productivity. Additionally, simple perforated tubes are an effective and innovative tool for farmers to implement AWD management. Our research suggests that farmers in eastern India and similar rice-growing agro-ecologies could reduce the irrigation water applied and increase water use efficiency while maintaining rice crop productivity by combining dry direct seeding with a medium-duration rice variety under AWD irrigation management.

Optimizing irrigation strategies to increase water utilization efficiency and achieve higher yield is vital for balancing groundwater use and improving food security during water shortage in the North China Plain (NCP). Based on a 16-year field experiment (2003–2018) using seven irrigation schedules from W0M0 to W4M3 (numbers are irrigation times in wheat (W) and maize (M) season, 75 mm each) in the winter wheat–summer maize double cropping system, we analyzed annual total water consumption (ETa) and groundwater table change in terms of net groundwater depletion, annual total grain yield, water productivity (WP), irrigation water productivity (IWP) and marginal benefit of the whole wheat–maize system. Relationship between yield or WP and irrigation or ETa were also revealed. Results showed that (1) total ETa increased as irrigation input increased, ranging from 427.3 mm (Rainfed, W0M0) to 891.0 mm (W4M3). Soil water storage contributed nearly 30% to ETa for winter wheat under water deficit conditions. Pre-sowing soil water storage played an important role in improving the annual yield and WP of both wheat and maize by promoting germination, seedling emergence and root growth; (2) the rainfed treatment (W0M0) was best for mitigating the groundwater table decline (0.1 m yr-1), followed by W1M1 (0.5 m yr-1) and W2M1 (0.8 m yr-1). Groundwater table decline in M2W2 almost overlapped the observed data at the station (1.1 m yr-1). In W3M2, the farmers’ traditional practice, the groundwater table declined by 1.4 m yr-1, obviously over exploitation, while W4M2 and W4M3 declined by almost 2.0 m yr-1; (3) the relationship between total annual yield and irrigation (or ETa) followed a quadratic curve. Total annual yield significantly increased from W0M0 to M1W1 (25%) to M2M1 (5%) and then kept stable. Average annual WP decreased as irrigation increased, from 2.4 kg m-3 (W0M0) to 1.6 kg m-3 (W4M3). Average annual IWP and marginal benefit also declined as irrigation increased. These results over 16 years indicated that the W2M1 is the most balanced irrigation regime for wheat– maize rotation to mitigate groundwater decline, maintain grain production, and improve water use efficiency in the NCP.

Dormant seeding (DS) has become popular in dry areas because it provides a longer growing season and optimum temperature during the early spring to grow crop. Long-term daily weather data for the period of 1984–2014, were collected for ten locations in northwestern Iran with a cold semi-arid and arid climate. The SSM-legumes model was used to investigate the effect of dormant seeding versus different fixed spring sowing dates as well as cultivars on the yield and water use efficiency (WUE) of lentil. The results showed that, the highest average grain yield across all the study locations was obtained for DS management and decreased around 49% when sowing date was delayed to 4 April. Furthermore, with a delay in sowing date, the decline in grain yield of short- cycle and long- cycle cultivars was 42% and 58%, respectively. On average, WUE for short- cycle cultivar was much higher than long-season cultivar (6.2 and 4.0 kg ha−1 mm−1, respectively). The combination of short-cycle cultivar × DS management resulted in 30% and 29% increase in grain yield and WUE, respectively when compared with a long-cycle cultivar × DS management. This conclusion was reached because DS sowing and short-cycle cultivar increased yield and its stability due to the proper establishment and appropriate growth conditions of lentil in late winter and early spring. DS also resulted in better use of precipitation and escape from the heat and drought stresses in late spring and early summer, provided that there is no frost risk in the target regions. Overall, the results of the simulations for all the study locations suggested that sowing lentil using DS is indeed superior over the other fixed spring sowing practices because it not only shortens the frost risk to seedlings but also provides optimal conditions for the growth and use of rainfall and soil moisture as well as lentil growth.

As a critical link between carbon and water cycles, water use efficiency (WUE) is an important metric for assessing ecosystem response to climate change. However, the controlling mechanism of WUE is still unclear because a number of environmental factors are usually cross-correlated in natural systems. Using the structural equation modeling (SEM) method, this study investigated the seasonal and inter-annual variations of WUE and their controlling mechanism based on 10 years of eddy covariance data in a rainfed maize cropland. The results showed that annual WUE varied between 2.1 g C kg−1H2O and 3.6 g C kg−1H2O, with a multi-year mean of 2.8 g C kg−1H2O. At a daily timescale, leaf area index (LAI) was the primary controlling factor of WUE, while air temperature (Ta) and vapor pressure deficit (VPD) were both shown to have significant indirect effects on WUE through regulating LAI. Distinct controlling mechanisms of daily WUE were detected for years with different hydro-climatic conditions. The primary controlling factors were generally consistent in the 3 dry years (LAI, Ta and VPD). Moreover, WUE consistently showed negative response to soil water content in dry years, while an opposite response was found in wet years. Mean annual Ta was shown to explain 54% of the inter-annual variation of WUE. Despite the insignificant relationship between WUE and precipitation amount at an annual scale, the precipitation frequency was found to be a good predictor of the annual WUE. These findings provide important implications for the accurate simulation of ecosystem WUE, especially under drought conditions in semi-arid regions.

Three oat (Avena spp.) and three field pea [Pisum sativum subsp. arvense (L.) Asch.] cultivars were grown in pure stands and interspecific, binary mixtures under Mediterranean conditions for two growing seasons (2011–12 and 2012–13). The aim of the work was to identify traits contributing to the complementary use of soil nitrogen (N) and water in intercrops. Such traits could be used as putative selection criteria for cultivars well-adapted to intercropping systems. The 15N natural abundance method was used to assess the percentage of N derived from N2-fixation (%Ndfa) in pure stands and intercrops and the percentage of N transferred from pea to oat (%Ntrans) in intercrops. Carbon isotope discrimination (Δpea, Δoat) was used as an assessment of water use efficiency. Isotope determinations were conducted when 30% of pea flowers were open. Dry matter yield (DM) of pure stands and intercrops was estimated at forage silage maturity of peas, and forage quality traits (protein, fat, ash, crude fiber, and nitrogen free extracts concentrations) were measured. Intercropping either increased or decreased %Ndfa depending on the cultivars included in the mixtures. High %Ndfa by pea in mixtures was associated with a high contribution of pea in the mixture and high crude protein concentration in DM. High amounts of fixed N and N accumulated in pea were necessary to maximize protein concentration and protein yield in intercrops. These amounts were calculated to be 72.0 and 94.4 kg N ha−1 for protein concentration and 124.2 and 160.8 kg N ha−1 for protein yield. Oats in intercrops seemed to affect the N niche of peas. Δoat values were positively correlated with %Ndfa, the amount of fixed N in pea and the amount of N accumulated in pea. A plausible explanation for this is that high Δoat values were indicative of a better access to soil water and nitrate (NO3-N) sources through a deeper and denser rooting system, thus increasing the competition on the companion pea which led to higher percentage of N2-fixation and consequently to higher amounts of N fixed by and accumulated in pea. High-Δ oats were less dependent on N transferred from pea as was indicated by a negative correlation between these two traits. As a consequence, high Δoat values were associated with high protein concentration and protein yield. In contrast, Δpea values were negatively correlated with protein concentration and protein yield. Peas, having a less competitive rooting system compared to oats, were adaptive to intercropping when they had a more conservative use of soil water (lower Δpea), and thus avoided competition. Land equivalent ratios for dry matter yield (LERDM) and protein yield (LERCPY) were affected by growing seasons. LERDM was 62% of season’s water input) and mild temperatures during winter (November to February). The very early, moderately tall oat cultivar Flega had the highest LER values, regardless of the companion pea cultivar. This was an indication that Flega was favored by growing in intercrops, however, Flega’s mixtures were not among the high-yielding mixtures.

Drought and nutrient deficiency are the principal factors limiting crop production in arid and semi-arid areas. Conservation tillage can maintain and increase grain yields by enhancing soil fertility and conserving more soil water in the field. However, farmers without access to mineral fertilizers cannot compensate for the soil nutrient deficiencies for crop production, and the crops will suffer yield reductions. Site-specific fertilizer application with conservation tillage practice management is the key to achieving a high and sustainable crop yield. A long-term (2007–2016) two-factor, spilt-plot experiment was established to assess the effects of fertilization {balanced fertilization (BF), low fertilization (LF), conventional fertilization (CF)} and conservation tillage practices {no tillage (NT), subsoiling (ST), conventional tillage (CT)} on grain yield, soil water and soil nutrients. The aim of this experiment was to select an optimal fertilization and tillage management system for crop production in the Loess Plateau, a typical semi-arid and rainfed area of China. Ten-year data showed that subsoiling with balanced fertilization (BST) increased the grain (6465 kg ha−1) and straw yield (9792 kg ha−1), but no tillage with balanced fertilization (BNT) was observed to provide the highest economic profit for farmers (6416 yuan ha-1). No tillage with low fertilization (LNT) was the optimal management for soil water conservation in fields that could preserve more soil water in fallow land (mean value: 425 mm) and provide more soil water during the wheat (mean value: 387 mm) and maize (mean value: 420 mm) growth season. The LNT consumed less soil water in the crop growth season (mean value: 105.4 mm), but the BST (18.5 kg ha−1 mm−1) showed a higher water use efficiency (WUE). The BF and NT showed better soil nutrient conditions (soil organic matter(SOM), available N, P and K) over the ten years and provided better soil water and balanced soil nutrient conditions for crop growth. The BNT and BST were recommended as the optimal and economic fertilization with tillage management systems for maintaining high grain yields by using soil water efficiently and enhancing soil fertility in a winter wheat-spring maize rotation on the Loess Plateau.

Drought, water loss and soil erosion are the main factors restricting grain production and economic development in the semiarid hill areas of Loess Plateau, China. A field experiment was conducted to determine the effects of different tillage systems (open-ridging and tied-ridging) on soil water moisture, runoff, sediment yield, fodder yield and water use efficiency (WUE) on 2 slopes (5° and 10°), using traditional planting (without ridges and furrows) as a control, during 2 consecutive alfalfa growing years: 2015 and 2016. Results indicated that the benefits of fodder yield and WUE increase from tillage system were more effective than the benefits from slope gradient on slight sloping land. Open-ridging and tied-ridging decreased runoff and sediment transport and increased soil moisture, fodder yield and WUE of alfalfa. The decrease of sediment for open-ridging and tied-ridging was 85.1% and 88.4%, respectively, for slopes of 5°, while it was 83.9% and 89.0% for slopes of 10°. Only 7–10% rainfall events produced runoff and 4–6% rainfall events produced sediment. The mean runoff efficiency for traditional planting, open-ridging and tied-ridging was 11.6%, 9.1% and 6.7%, respectively, for slopes of 5°, while it was 13.4%, 10.0% and 7.8% for slopes of 10°, over 2 years. Increase of fodder yields for open-ridging and tied-ridging was 34.6% and 19.8%, respectively, for slopes of 5°, while it was 32.7% and 20.6% for slopes of 10°, over 2 years. The average WUE for open-ridging and tied-ridging was respectively 1.96 and 1.85 times greater than that for traditional planting, for slopes of 5°, while it was 1.88 and 1.77 times greater than that for traditional planting, for slopes of 10°, over 2 years. The mean runoff and sediment for slopes of 10° was 1.14–1.16 and 1.19–1.57 times that for slopes of 5°, respectively. The differences of fodder yield and WUE between slopes of 5° and slopes of 10° were not significant. Tied-ridging rainwater harvesting offered particular effects on water and soil conservation, while open-ridging offered particular effects on fodder yields and WUE enhancement during the first and the second growing seasons.

The practice of straw retention often causes seedling issues, including slow seedling establishment and weak seedling. Irrigation shortly after sowing (namely ‘sowing irrigation’, abbreviated as SI) may help to accelerate the seedling establishment under straw retention, and appropriate split nitrogen (SN) management may further boost crop growth and grain yield. Here, we conducted a 2-year field trial to assess the impacts of SI and SN on crop growth, grain yield and water and nitrogen use efficiencies of a maize hybrid i.e. Zhengdan 958 grown under straw retention. The treatments consisted of two irrigation conditions and three splitting nitrogen regimes, with three replications. SI treatment was composed of 0 mm irrigation (denoted as W0) and 60 mm irrigation (denoted as W1) shortly after sowing. SN management contained a similar total nitrogen rate (300 kg ha−1) but was split in three proportions between sowing and big flare stage, i.e. 10:0 (denoted as N1), 5:5 (denoted as N2) and 3:7 (denoted as N3). Our results indicated that sowing irrigation accelerated seedling emergence by 2–7 days, and increased grain yield by 4.73% (2014) and 5.90% (2015), and water use efficiency by 1.69% (2014) and 3.80% (2015) compared to the treatment without sowing irrigation. N2 and N3 treatments increased grain yield by 9.00–10.12% via greater kernel number, and increased nitrogen partial factor productivity by 9.35–10.20% in both years. The improved grain yield by sowing irrigation or splitting nitrogen was due to greater canopy photosynthetic capacity with higher leaf area index, leaf chlorophyll content and net photosynthesis rate. It was found that the optimal ratio of basal: topdressing nitrogen depended on whether sowing irrigation was used. Without sowing irrigation, W0N2 produced the highest grain yield; while with irrigation, both W1N2 and W1N3 produced a greater production than W1N1. In conclusion, the combination of sowing irrigation and splitting nitrogen to the big flare stage could increase not only maize grain yield, but also resource-use efficiency under straw retention in lime concretion black soil of Huaibei Plain, Anhui Province, China.

Terrestrial ecosystems are expected to experience more intense and longer drought and heat-waves in the future. How these environmental factors and their interaction influence photosynthetic activity and water use efficiency remains, however, an open question. Since the photosynthetic activity determines yield response, we investigated gas-exchange and chlorophyll fluorescence traits of flag leaves in four winter wheat cultivars, including two genotypes widely grown in Central Europe and two genotypes considered as drought tolerant. Pot-grown plants were cultivated under natural field conditions until anthesis (DC 61). Subsequently, the plants were exposed to a set of temperature regimes with daily maxima of 26–41 °C (temperature treatment) and maximum soil water holding capacity above 70% and below 30% (drought treatment) using laboratory growth chambers. Primary photochemical reactions after 7 and 14 days of acclimation, measured as maximum quantum yield of photosystem II photochemistry and total chlorophyll content, showed typical interactions of temperature and water availability resulting in an amplified response under combined influence of drought and temperatures above 35 °C. In contrast, drought and temperature treatment had only minor effects on content of epidermal flavonols. A dominant effect of drought over temperature on stomatal conductance (GSmax) was observed. Although substantial genotype-specific responses were found, reduced stomatal conductance resulted in significant decrease in light-saturated rates of CO2 assimilation (Amax) in all genotypes studied. The GSmax–Amax relationship, however, revealed limitation of CO2 uptake by other, non-stomatal processes at temperatures above 32 °C, particularly in the sensitive genotypes. Strong interaction of combined drought and temperature treatments was found on water use efficiency (WUE). Decline in WUE with increasing temperature was steeper in water-deficit than well-watered plants of all genotypes studied. Our results thus document a strong interactive effect of elevated temperature and drought on photosynthetic carbon uptake. Detected thresholds of sensitivity to combined drought and heat stress will contribute to improved modelling of wheat growth and production under expected future climate conditions.

Large-scale vegetation construction has generally led to soil desiccation in arid and semi-arid regions. Energy crops with high biomass and water use efficiency are generally beneficial to agriculture and the environment. It is necessary to understand how to maintain the dynamic balance of soil moisture and biomass production on herbaceous energy croplands. In this study, soil moisture data at different depths of soil were obtained from long-term field observations for two energy crops, i.e., Panicum virgatum and Miscanthus sinensis, and a forage crop-Medicago sativa. Relative aridity of the soil and plant biomass were compared among different vegetation types, transects, and cultivation years. Medicago sativa soil was severely, even extremely, desiccative with increasing cultivation years, whereas there was nearly no desiccation in the soil of energy crops. The values of compared soil water storage compensation indexes in deep soil layers were higher than those in shallow soil layers, with the evaluated soil water storage compensation index being the smallest in the 40–80 cm layer. Energy crops had significantly higher aboveground biomass, mostly exhibiting more than 2.6 kg m−2, while the aboveground biomass of M. sativa was only above 0.5 kg m−2. Furthermore, the water use efficiencies of energy crops were obviously higher than that of M. sativa (P

Excessive pumping of groundwater over the years to meet the high irrigation water requirement of rice-wheat system has resulted in over exploitation of groundwater in the Indo-Gangetic plains (IGP) of India. Replacement of traditional rice with less water crops such as maize under conservation agriculture (CA) based management (tillage, crop establishment and residue management) practices are required to promote sustainable intensification. Furthermore, inefficient nutrient management practices are responsible for low crop yields and nutrient use efficiencies in MW system. A 3-year field experiment was conducted in farmer’s participatory strategic research mode at Taraori, Karnal, India to evaluate the effects of tillage and crop establishment (TCE) methods, residue management, mungbean integration, and nutrient management practices on crop yields, water productivity and profitability of MW system. The main plot treatments included four combinations of TCE, residue and mungbean integration [conventional tillage (CT), conventional tillage with mungbean (CT + MB), permanent bed (PB) and permanent bed with MB (PB + MB] with three nutrient management practices [farmer’s fertilizer practice (FFP), recommended dose of fertilize (RDF) and site specific nutrient management (SSNM)] using Nutrient Expert® as sub plot treatments. System productivity, water use efficiency (WUE) and net returns under PB + MB were significantly increased by 28.2–30.7%, 27.8–31.0% and 36.8–40.5% compared to CT respectively, during three years of experimentation. Integration of MB in MW system contributed 24.9 and 27.6% increases in system productivity and net returns compared with no MB, respectively. SSNM based nutrient management increased the mean (averaged across 3 yrs) system productivity, WUE and net returns of MW system by 13.4%, 13.3% and 15.3% compared with FFP, respectively. Study showed that conservation agriculture based sustainable intensification (PB + MB) and SSNM approach provided opportunities for enhancing crop and water use efficiency, and profitability of MW system in North-West IGP of India.

Achieving the combination of high water use efficiency (WUE) and high yield is very important for the sustainable development of wheat production in the North China Plain (NCP). For this study, we investigated how to optimize timing of two irrigations to improve winter wheat grain yield and WUE under field conditions. No-irrigation after sowing (W0) as a control, and six irrigation treatments as follows: irrigation of 75 mm each at late tillering and booting (TB), at late tillering and anthesis (TA); at late tillering and medium milk (TM), at jointing and anthesis (JA), at jointing and medium milk (JM) and at booting and medium milk (BM). Experiments were conducted between the 2014–2016 growing seasons. In all the treatments, JA achieved the highest grain yield (9,267.6 kg ha−1) and WUE (20.2 kg ha−1 mm−1). Compared with TB, TA and TM, JA coordinated pre- and post-anthesis water use, reduced pre-anthesis and total evapotranspiration (ET), and increased post-anthesis water use amount and ratio; JA reduced biomass at anthesis, but optimized allocation of assimilation, increased spike partitioning index and maintained high fruiting efficiency, and thus obtained the highest grain number per m2 (GN, 23.7 103 m−2). Meanwhile, JA optimized crop characteristics with appropriate leaf area index (LAI), delayed leaf senescence, extended grain filling duration by 1–3 days, then increased biomass post-anthesis and harvest index (HI). Compared with JM and BM, JA increased GN, biomass post-anthesis and grain yield as well. These results demonstrated that irrigation at jointing and anthesis could improve grain yield and WUE by increasing biomass post-anthesis, HI and GN. Therefore, we propose that under adequate soil moisture conditions before sowing, two irrigations at jointing and anthesis with 150 mm irrigation amount is the optimal limited irrigation practice for wheat production in NCP.

In the semi-arid regions of China, ridge-furrow (RF) planting system is being gradually implemented, in order to improve the soil moisture status and water utilisation efficiency. This study aimed to improve the efficiency of the RF system by investigating the effects of three planting densities (L: 52,500 plants ha−1; M: 75,000 plants ha−1; H: 97,500 plants ha−1) and four kinds of limited irrigation modes (NI: no irrigation; IV: irrigation at the vegetative stage with 11 leaves; IS: irrigation at the silking stage; and IVS: irrigation at the vegetative and silking stages). Maize (Zea mays L.) plants mainly consumed the top surface of (0–60 cm) soil water, whereas the deep layer (120–200 cm) of soil moisture was less affected under the RF system, and the average soil water storage of 0–60, 60–120, and 120–200 cm decreased by 58.7, 39.1, and 7.1 mm, respectively, during the entire growth period. Limited irrigation at the vegetative and silking stages had a positive effect on biomass, leaf area index, and evapotranspiration, but did not significantly increase grain yield, water use efficiency (WUEG), irrigation WUE (IWUEG), and irrigation water productivity (IWPG). The average data obtained over two years showed that medium planting density with limited irrigation at the silking stage (M-IS) treatment significantly increased WUEG, IWUEG, and IWPG by 5.7, 98.5, and 92.6%, respectively, compared with those in the M-IVS treatment. Economic benefit analysis also showed that M-IS treatment resulted in greater net profit (2313.3 USD ha−1). Thus, the M-IS treatment could be a suitable planting model for improving maize grain yield, economic benefit, and water use in the semi-arid regions of China.

A field experiment was conducted to explore the effect of different sowing time and seeding rate on yield components and water use efficiency (WUE) of winter wheat by regulating the growth redundancy and physiological traits of root and shoot. Winter wheat sowing was performed on Oct.12 (T1), Oct.22 (T2), Nov.3 (T3), respectively. There were three treatments of different seeding rates, i.e. 112.5 kg hm−2 (D1), 150 kg hm−2 (D2) and 225 kg hm−2(D3) in each sowing time. The results showed that sowing time and seeding rate significantly influenced the morphological and physiological characteristics of winter wheat. Plant height, ineffective tiller number, leaf area and root biomass decreased significantly along with the delay of sowing date. Plant height, ineffective tiller number and root biomass increased significantly and leaf area decreased significantly with increasing seeding rate. Under the same seeding rate condition, T1 had the highest number of ineffective tiller, and T3 had the lowest one. Delayed sowing (T2 and T3) increased significantly root activities and leaf photosynthetic rate (Pn) in the late growing stage, and decreased significantly root respiration rate (Rroot) per unit area of wheat. In the same sowing time treatment, root activities and leaf Pn decreased significantly and Rroot increased significantly with the increase of seeding rate; however, seeding rate had no effect on root activity and leaf Pn in T3 treatment. Grain yield decreased significantly in T1 and increased significantly in T3 with the increase of seeding rate, and it was the highest in D2 and the lowest in D1 in T2 treatment. Delayed sowing lowered significantly soil water consumption of crop. Under the same sowing time condition, soil water consumption increased significantly as seeding rate increased. WUE decreased significantly with the increase of seeding rate in T1and T2 treatments. In two test years, T2D2 had highest grain yield and WUE, and T3D1 had lowest grain yield and WUE. The interaction of sowing time and seeding rate also had significant effect on soil water consumption, grain yield and WUE. It is clear that appropriate sowing time and seeding rate (T2 Treatmeat) can increase grain yield and WUE of winter wheat by regulating the growth redundancy and physiological traits of root and shoot, but excessive reduction of vegetative organs (T3 Treatmeat) can affect crop production.

Water and nutrient management are major corners in the improvement of productivity and sustainability of rainfed soybean-wheat cropping systems (SWCS). A nine-year-old (2006–2014–15) field experiment was started to explore the effects of recommended dose of farm yard manure (FYM) in SWCS, recommended dose of nitrogen, phosphorus and potassium fertilizers (RDF) along with FYM, FYM + 50% NPK, NPK, FYMsoybean + NPKwheat and without application of NPK and FYM (CK) under rainfed (I0) and supplementary irrigation (I1) situation in SWCS. Results from nine years continuous fertilization of NPK + FYM showed significantly highest grain yield of wheat (2.70 and 3.80 t ha−1) and soybean (2.50 and 2.74 t ha−1) under rainfed (I0) and supplementary irrigation (I1), respectively as compared to rest of treatments. Significant (p

Xinjiang is the main cotton-growing region in China, but the shortage of water resources and the low utilization of fertilizers have restricted its agricultural development. Field experiments were conducted during 2012–2014 to investigate the coupling effects of different amounts of water and fertilizers on seed cotton yield, water and fertilizer use efficiency as well as economic benefits in northern Xinjiang of Northwest China. The optimum combinations of water and fertilizer inputs were determined for both single-objective and multi-objective optimizations through the least squares method and multiple regression analysis. The main plots comprised of five N-P2O5-K2O fertilization levels (150-60-30, 200-80-40, 250-100-50, 300-120-60 and 350-140-70 kg ha−1), which were designated as F0.6, F0.8, F1.0, F1.2 and F1.4, respectively. Three drip irrigation levels, designated as full irrigation (1.0 ETc, ETc is the crop evapotranspiration), medium irrigation (0.8 ETc) and low irrigation (0.6 ETc), were assigned as the sub–plots. For the same fertilization level, the results revealed that leaf area index (LAI), dry matter accumulation, seed cotton yield, partial factor productivity (PFP) and the economic benefits increased with increasing irrigation water. These parameters reached their maximum values at the irrigation amount of 1.0 ETc. At the same irrigation level, the LAI, dry matter accumulation, seed cotton yield and water use efficiency (WUE) first increased and then decreased as the amount of fertilizers increased. These parameters were maximized in 2012 and 2014 when 300-120-60 kg ha−1 of fertilizers (N-P2O5-K2O) was applied. A low level of irrigation was not conducive to the functioning of fertilizers. The WUE was low, but the seed cotton yield and economic benefits were obviously higher under the full irrigation level. Therefore, based on the results of this study, full irrigation along with a fertilizer rate of 300-120-60 kg ha−1 (N-P2O5-K2O) should be considered as the best fertigation strategy for both high seed cotton yield and economic benefits. By establishing a multi-objective optimization model using binary quadratic regression analysis, it was concluded that the seed cotton yield, economic benefits and water use efficiency reached ≥90% of their maximum values simultaneously when the irrigation interval was 362.3–462.5 mm and the fertilizer (N-P2O5-K2O) interval was 212.5-85-42.5 to 367.5-147-73.5 kg ha−1. The obtained optimum combinations of water and fertilizer can provide a scientific basis for irrigation and fertilization optimization and management in northern Xinjiang of Northwest China and other regions with similar environments.

Gravel mulching technology has been applied in the arid and semi-arid regions of Northwest China for many years. However, systematic field studies concerning its effects on ecological effects and water productivity are insufficient. A field study was conducted during two consecutive cycles of Wheat-Maize cropping system in the Yangling District of Northwest China to evaluate water productivity and crop productivity with the four treatment combinations: CK (control, no mulching), WCK (CK plus 50 mm irrigation), GM (CK plus 8 kg/m2 gravel mulching, covering 100% of soil surface) and WGM (WCK plus GM). Soil temperature, soil moisture, total biomass and yield were significantly increased, whereas CO2 emissions were decreased by gravel mulching treatment over the control. System yield improved by 19.87% and 15.59% by applying 50 mm irrigation, 53.58% and 43.18% by applying gravel mulching and 60.64% and 48.28% by applying gravel mulching and 50 mm irrigation over the control during both the cycle of Wheat-Maize rotation, respectively. Gravel mulching results in a positive contribution to annual net primary productivity (NPP) and net ecosystem exchange (NEP), and high-water use efficiency (WUE) were achieved under gravel mulching treatment for the two rotation cycles. Annual WUEeco and WUEyield significantly increased by 40.6% and 49.2% and 57.6% and 51.4% under the gravel mulching treatment over the control during the two cycles, respectively. However, during cycle 1 WUEveg and WUEbio did not significantly affected whereas during cycle 2 it affected, with a maximum value of 14.4 kg ha−1 mm−1 in WGM and 47.1 ± 5.1 kg ha−1 mm−1 in GM, respectively. Taking into account crop yield, ecological effects and water use, covering the soil with gravel is an effective approach to enhance multilevel water use efficiency while increasing the productivity of wheat-maize cropping system in semi-arid regions of China.

The farming practice of alternating ridges–furrows with plastic film mulching is widely used to improve field productivity of most staple crops such as maize and wheat in the semiarid Loess Plateau, but whether the technology has similar benefits on oil crops such as linseed flax (Linum usitatissimum L.), still remains unknown. From 2012–2013, a 2–year field experiment was carried out to evaluate the effects of different ridges–furrows mulching patterns on soil hydrothermal parameters, linseed yield performance, water use efficiency and economic benefit at a rainfed semiarid site of the Loess Plateau. Four different treatments were designed as: i) alternating small and large ridges with full film mulching (RFM), ii) alternating ridges and furrows with plastic film mulching only on the ridges (RM), iii) flat planting with fully film mulching (FM) and iv) conventional flat planting without mulching (CK). Local widely cultivated variety Tianya 9 was used as testing cultivar. The results indicated that soil water storage during early growing stage was increased by 7.1%, 0.6% and 6.3% in RFM, RM and FM, respectively, compared with that of CK across two growing seasons. After harvesting, soil water storage in RFM was recovered to higher level than that of CK. Average soil temperature at seedling stage was 3.1 °C and 2.1 °C higher in RFM and FM than that of CK. In addition, film mulching generally accelerated crop development during early vegetative period, leading to a shorter growing season in RFM and RM. Particularly, both linseed yield and water use efficiency were enhanced by 116.2% and 154.8% in RFM, 50.3% and 72.4% in RM, 87.5% and 84.2% in FM across two growing seasons, respectively, compared with those of CK. Critically, the greatest net income and output to input ratio were achieved in RFM across both growing seasons. Present results clearly suggest that the practice of alternating small and large ridges with full film mulching provide an innovative option to optimize soil hydrothermal conditions, thereby boosting the productivity and profitability of dryland linseed flax in rainfed semiarid environment.

The plastic-covered ridge and furrow rainwater harvesting planting system (RFRHP) has been widely used for increasing and stabilizing the crop productivity in the semiarid areas of northwest China. During 2012–2015, we performed a consecutive field experiment to evaluated the influence of rainwater harvesting planting with supplementary irrigation (RI) on the water irrigation use and water use efficiency by winter wheat in a semiarid climate using the following 8 treatments: the rainwater harvesting planting system supplemented with 375 m3 ha−1 irrigation during the early growth stage (R1), both the early and late stages (R2), late growth stage (R3), and no irrigation during whole winter wheat growth stage (R0); the traditional flat planting supplemented with 750 m3 ha−1 irrigation during the early growth stage (B1), both the early and late stages (B2), late growth stage (B3), and no irrigation during whole winter wheat growth stage (B0). We found that although the irrigation amount was double under traditional flat planting, but the soil water content in the 0–120 cm soil layer did not differ significantly between the rainwater harvesting planting with supplementary irrigation treatments (RI) and border irrigation treatments (BI). The rainwater harvesting irrigation (R1, R2, and R3) treatments reduced the irrigation water amounts required (750–1125 m3 ha−1) and alleviated drought stress during key winter wheat growth periods, it also could maintain higher grain yield (1.9%) without irrigation or with irrigation amount reduction by 50%. The irrigation water utilization efficiency of rainwater harvesting irrigation (RI) treatments under the condition of irrigation amounts reduction by 50% was improved significantly, i.e. compared with border irrigation (BI) treatments, the irrigation water use efficiency (IWUE) and water productivity (IWP) increased by 0.9–1.1 and 0.2-0.6 times, respectively, and the net incomes of farmers could increase by 718 Chinese Yuan ha−1.

Fallow tillage methods play a major role in improving soil water storage, water use efficiency and hence grain yield in winter wheat (Triticum aestivum L.) cropping system in southeast Loess Plateau. However, the efficacy and stability of such methods need to be further validated in long-term field observation. From 2009–2015, a 7-year filed experiment was established in winter wheat fields at Wenxi Agriculture Station, semiarid southeast Loess Plateau. The objectives were to determine the responses of soil water storage, utilization and yield formation to three different tillage methods: including deep ploughing, subsoiling and no-tillage. Our results indicated that compared to no-tillage, the soil water storage (0–300 cm depth) was averagely increased by 7.8% and 6.0% during fallow season, 13.7% and 9.8% in growing season under deep ploughing and subsoiling respectively. Furthermore, the increasing magnitude in soil water due to deep ploughing and subsoiling was, on average, 10.1% and 5.5% higher in dry season than that in wet one. Improved soil water condition under deep ploughing and subsoiling significantly increased the ear number and grain yield by 20.2% and 15.9%, 30.8% and 25.8% respectively, but did not affect seed number and weight of thousand seed over the experimental seasons. Moreover, grain yields under deep ploughing and subsoiling were averagely increased by 35.2% and 24.8% in dry season, 28.7% and 20.6% in wet season respectively. Accordingly, water use efficiency and precipitation use efficiency were increased by 12.1% and 31.9% under deep ploughing, 11.1% and 25.0% under subsoiling respectively. Critically, we found that with an increase of 10% water storage efficiency during fallow season, ear number, grain yield and WUE could be increased by 0.2 million ha−1, 241.1 kg ha−1 and 0.6 kg ha−1 mm−1 respectively. Our study clearly indicated that deep ploughing in fallow season should be adopted as a promising strategy to retain soil water availability and hence boost wheat productivity in semiarid southeast Loess Plateau.

Development of sustainable agronomic practices and increasing crop water use efficiency (WUE) under the realm of water scarcity and climate change have become the major focuses in the semiarid Loess Plateau region of China. This 7-yr (2001–2007) study investigated the effects of conservation tillage practices and residue management on crop yield, WUE, soil organic carbon (SOC), soil water storage, economic return, and determined the contribution of various environmental factors on crop WUE under a two-year cycle spring maize ( Zea mays L.)-winter wheat ( Triticum aestivum L.)-summer soybean ( Glycine max L.) rotation cropping system. Treatments included conventional tillage (T) as control, conventional tillage followed by straw mulching (TS), no tillage (NT) and no tillage followed by straw mulching (NTS). Averaged over years and species, the overall crop yield was greatest under TS treatment, which was 17 9 and 5% significantly greater than NT, T and NTS treatments, respectively. Additionally, TS treatment resulted in comparable or greater crop WUE than other treatments starting from 2004. Soil moisture storage was not significantly affected by treatments but varied greatly across different soil depths throughout the growing season. Soil organic carbon was significantly increased by straw mulching treatments (NTS and TS) beginning at 2004. In all, NTS treatment provided the greatest economic return on a system basis. Our simulation modeling results indicated that biomass and net radiation are the most important factors in determining WUE in the semiarid Loess Plateau of China.

High inter-seasonal rainfall variability presents the biggest risk for farmers to invest in best management practices in maize grown in much of Ethiopia. Optimising genotype (G) and management (M) of maize for different growing environments (E) could alleviate risks associated with seasonal rainfall variability and enhance reliability of production of this crop. In this study, we explored this possibility with the help of the APSIM maize model. The model was first calibrated and then tested on different sets of data for its ability to simulate phenology, dry matter and yield of six genotypes of differing maturity grown under rainfed conditions at four plant densities at four sites including Bako, Hawassa, Melkassa and Adamitulu in Ethiopia in 2013 and 2014. The model accurately predicted plant available soil water (NRMSE = 6%), days-to-flowering (NRMSE = 4%), days to maturity (NRMSE = 4%), leaf area index (NRMSE = 6%), biomass (NRMSE = 13%) and yield (NRMSE = 5%). The simulations revealed that increasing plant density increased water use efficiency of genotypes at all sites. The model in conjunction with site-specific soil properties and 33 years of daily weather data was then used to simulate changes in the water supply demand ratio to determine dominant drought patterns at each site which could be clustered into four major drought patterns. These drought patterns included low stress occurring in 55% of the seasons, mid-season occurring in 11% of the seasons, early terminal drought in 17% of the seasons, and late terminal drought 17% of the seasons. The frequencies of these drought patterns varied at different sites. These could also be manipulated by genotypes of different maturity and plant density resulting in different yield outcomes at each site. The study revealed significant scope for yield improvement by manipulating G and M, with larger effects in favourable seasons.

Water shortage has been a challenge to sustainability of maize (Zea mays L.) production in many irrigated agriculture regions. Adoption of drought-tolerant (DT) hybrids could be a management strategy for maize production under water-limited conditions. The objective of this study was to investigate the differences in soil profile water extraction patterns at vegetative and grain filling stages, dynamics of evapotranspiration (ET), yield, and water use efficiency (WUE) in maize hybrids differing in drought tolerance characteristics in a semiarid environment. Field experiments were conducted in 2014 and 2015 in two conventional (33D53AM and N74R) and two DT hybrids (P1151AM and N75H). The hybrids were grown under two water regimes (I100 and I50, referring to meet 100% and 50% of ET requirement, respectively). Comparing the well-watered plants at I100, water stress at I50 reduced seasonal ET by 22–41%, grain yield by 30–48% and yield components by 6–41%; however, water stress only reduced WUE by 8%. Although the DT hybrids did not always provide yield benefit, the Pioneer AQUAmax® hybrid P1151AM had about 30% greater grain yield and WUE than the conventional hybrid 33D53AM. Regardless of year, water regime and hybrid, greater maize yield was related to greater biomass at maturity, harvest index, kernel weight and kernel number. Under water-limited conditions, two DT hybrids consistently had 3–6% lower seasonal ET than the two conventional hybrids. Compared with the conventional hybrids, the two DT hybrids extracted less soil water along the profile at vegetative stage. However, there were no significant differences in soil water extraction among hybrids during the reproductive stage. The results of this study demonstrated that effective use of soil water during grain filling is important for maintaining high yield under water limited conditions.

The proper choice of a planting pattern is a key issue in the Corn Belt of Northeast China (CBNC) for national grain security and increasing the incomes of farmers. Field experiments were conducted from 2014 to 2016 in Lishu County, Jilin Province, China in order to evaluate alfalfa intercropping within the context of a uniform planting density of corn. The four treatments included corn monoculture (nC) as the control, 3-row corn intercropping with 3-row alfalfa cultivation (3C/3A), 3-row corn intercropping with 5-row alfalfa cultivation (3C/5A), and alfalfa monoculture (nA). Corn–alfalfa intercropping did not affect soil moisture in 2014. In 2015, the relative soil water content of the 3C/5A treatment was lower than that of the nC treatment, and the relative soil water content of the 3C/3A treatment was higher than that of the nC treatment. Biomass and yield under the 3C/5A treatment were greater than those under the nC treatment in a normal year (2014) and a wet year (2016). Biomass water use efficiency and net revenue under the 3C/5A treatment were similar with those under the nC treatment. Net revenue of the 3C/5A treatment was 14% higher than that of the nC treatment in a dry year (2015). Biomass, biomass water use efficiency, and net revenue under the 3C/5A treatment were higher than those under the 3C/3A treatment. The 3C/5A treatment was an effective planting pattern over the 3 years, with a total net revenue 443 USD ha−1 higher than that of the nC treatment. The nA treatment’s biomass and biomass water use efficiency were less than those of the nC treatment, but its economic benefit was highest among all treatments, with a total net revenue 2510 USD ha−1 higher than that of the nC treatment. Therefore, planting alfalfa as a monoculture or as part of a 3C/5A intercropping system is recommended to improve soil fertility and the development of animal husbandry while financially benefiting farmers.

Maize straw residues as a surface mulching material would be an effective soil water-saving practice in wheat production for a wheat-maize rotation system in northern China. Additionally, combining a mulching pattern and limited irrigation could play an important role in enhancing the productivity of winter wheat. Therefore, open field experiments were carried out during 2012–2014 to study soil water content in depth, water use efficiency (WUE), soil temperature, wheat grain yield and root parameters under a mulching pattern [each-row mulching (ERM) and double-blank row mulching (DRM) with three mulching masses of 0. 4.5 and 9.0 t ha−1] and limited irrigation [no irrigation (I0) and one-time irrigation in winter (I1)]. Results indicated that wheat yields increased (mean 3.3%) or decreased (mean 5.4%) a little under ERM groups with no irrigation. Irrigation for each row of mulch increased the wheat yield (mean 8.8%). With or without irrigation, yields under DRM0 were lower compared to ERM0, whereas, DRM4.5 and DRM9.0 had a higher grain yield than ERM4.5 and ERM9.0 (mean 25% under I0 and 18.8% under I1) as well as DRM0 (mean 24.1%). The DRM patterns with a high yield could have an equal effect with irrigation in winter. Additionally, irrigation could enhance the effects of DRM on wheat yield increase (mean 6.87 t ha−1in DRM4.5 and 7.06 t ha−1 in DRM9.0). Effective tillers and above-ground biomass would be the key factors for determining wheat yield, especially under certain mulching patterns, although these effects were not reflected in wheat roots. Mulching on soil temperature had a more significant difference in an early growth period than the later stages of wheat. An additional feature was that the DRM pattern had a persistent heat preservation effect in the regrowth stage, while there was a lower soil temperature in ERM groups in this stage when there was no irrigation. Mulching managed to shorten the period of negative accumulated temperatures of wheat (mean of 7 days under ERM and 15 days under DRM) under I0. Winter water irrigation enhanced the shorten effect to a certain extent. Mulching had a more significant water conservation effect in the overwinter stage with lower precipitation and higher soil evaporation. Soil water content under DRM groups was richer than ERM groups in the late growth stage, when there was lower plant density and evapotranspiration, but there was a higher yield and WUE (with a mean of 18.6% under I0 and 20.3% under I1). The results suggest that the DRM pattern optimizes soil temperature, water content, balance roots and group effects as well as increasing wheat yield. Thus, this approach could be a better field management option for wheat growth and yield production under the limitations of water in northern China.

Plastic-film mulch is an agricultural technology widely used for maize (Zea mays L.) production in northern China, but the effects of the interaction between cultivar and plastic-film mulch on the grain yield and biomass production have not been studied. Five maize hybrids, Jinsui 4; Jixiang 1; Pingyu 8; Xianyu 335 and Yuyuan 5, were assessed in 2014 and 2015 in plastic-film mulched and non-mulched ridge-furrow plots in a cold semiarid environment. In 2014, the grain yield of the five cultivars varied from 685 to 898 g m−2 with no mulch, and from 966 to 1228 g m−2 under mulch. In 2015 (drier and warmer than in 2014), the grain yield varied from 179 to 353 g m−2 without mulch, and from 548 to 1021 g m−2 with mulch. By incorporating the variation in grain yield over cultivars, mulch treatments and cropping years, Jixiang 1 was the highest yielding cultivar: in 2014 the grain yield reached 898 g m−2 under no mulch, compared to 1228 g m−2 under mulch, while in 2015 the grain yield was 329 g m−2 under no mulch compared to 1021 g m−2 under mulch. Cultivar and mulch independently affected the aboveground biomass and harvest index of maize. Jixiang 1 attained high yields as a result of average aboveground biomass, but high harvest index. Differences in maize water use efficiency (grain yield per unit of evapotranspiration) as affected by mulch and cultivar paralleled those of grain yield due to minor effects of mulch and cultivar on growing-season evapotranspiration. The effects of plastic-film mulch on maize root biomass in the upper 0.6 m soil profile and root/shoot ratio varied with cultivar. Averaging years and mulch treatments, Jixiang 1 had the smallest root biomass in the upper 0.6 m soil layer and Jixiang 1 and Jinsui 4 had smaller root/shoot ratios than the other three cultivars. We conclude that the effects of plastic-film mulch on the grain yield, root biomass and root/shoot ratio varied significantly with cultivar. A moderate aboveground biomass and high harvest index may give satisfactory grain yield in plastic-film mulched or non-mulched fields in hydrothermally-limited areas. A wide variation of root/shoot ratio with maize cultivar and cropping year indicated that using a fixed root/shoot ratio to estimate the root carbon input to the soil would induce large uncertainty.

The Indo-Gangetic Plains (IGP) of India is dominated with rice − wheat cropping system that occupies almost 10.5 million ha area. The sustainability of rice-wheat system is under threat due to numerous water-, nutrients-, weeds- and environment-related problems, mainly, due to the cultivation of rice. Suitable crop and soil management practices with a bias to conservation agriculture (CA) that can sustain soil and environmental health as well as improve crop and water productivity, are required for the Indian IGP. Maize can be a viable alternative to rice and a potential driver for diversification of rice-wheat system. The acreage of maize is on the increase in conventional and conservation agriculture-based cereal systems of India in recent years. Therefore, a field experiment, involving a maize (Zea mays L.)-wheat cropping system was undertaken on a sandy clay loam soil for three years (2010–11 to 2012-13) in New Delhi to evaluate the impacts of CA on crop and water productivity, profitability and soil organic carbon (SOC) accumulation. There were five CA-based treatments in first year, and two treatments were introduced in second year (2011-12) onwards. The experiment was laid out in a randomized complete block design with three replications. In all the residue retention plots, wheat residue was retained in maize crop and maize residue was retained in wheat crop under zero till conditions. Results showed that the plots under permanent broad bed with residue (PBB + R) and without residue (PBB) resulted in ∼29 and ∼26% higher maize grain yield, respectively than conventional tillage (CT) (2.6 t ha−1), but wheat grain yields were comparable in all the treatments in first year. Maize grain yield in second year under PBB + R and zero tillage with residue (ZT + R) were 55 and 43% higher than CT plots (2.8 t ha−1). Three-year mean maize yields due to PBB + R and permanent narrow bed with residue (PNB + R) were 28 and 15% higher than that in CT plots (3.3 t ha−1). The PBB + R resulted in 11% higher two-year mean water productivity in maize than PBB (∼without residue), but both these treatments were comparable in this regard in wheat. The ZT + R plots resulted in 14% and 22% higher two-year mean water productivity, respectively in maize and wheat than ZT plots. Overall, the plots under PBB + R had 57% and 19% higher mean water productivities in maize and wheat, respectively compared with CT plots. Again, the PBB + R plots gave 12% higher two-year mean net returns compared with CT plots. With regard to net returns, the plots under permanent narrow bed with and without residue (PNB + R; PNB) were inferior to PBB, PBB + R, ZT and ZT + R plots. Retention of both-season crop residues could significantly improve SOC concentration in surface (0–5 cm) soil. The PBB + R resulted in highest SOC pool at 0–30 cm soil layer, which was significantly higher than that in CT. This system showed maximum carbon sequestration potential. Thus, this CA practice, which involves PBB + R is superior to other practice. This would save water through higher water-use efficiency, and lead to accumulation of more carbon in soil with higher sequestration potential, besides giving sustainable production through maize-wheat system over the years. This can be adopted across the IGP regions of India, where irrigated rice-wheat system is in practice, and in similar agro-ecologies of the tropics and sub-tropics under irrigated conditions.

Alfalfa (Medicago sativa L.) is an important forage legume in farming and animal husbandry systems in semiarid areas. However, its forage yields in dryland farming areas are usually very low due to water shortages and low soil phosphorus (P) availability. This study assessed the effects of plastic film mulch and P fertilization on alfalfa forage yield and shoot P uptake in response to improved soil moisture and soil P availability in a dryland farming system of northwest China. A six-year field experiment, which commenced in 2011, was conducted at Yuzhong County, Gansu Province, China in randomized blocks of split-plot design with two mulch treatments—plastic film mulch with ridge and furrow (M) and no plastic film mulch with flat planting (NM)—as the main plots, and four P levels—0, 9.73, 19.3, 28.9 kg P ha−1—as split plots. Alfalfa forage yield and shoot P uptake and concentration increased linearly with increasing P level in the NM treatment. In the M treatment, shoot P concentration also increased linearly with increasing P level, but shoot P uptake and forage yield were well-fitted by a quadratic model with P level as the independent variable and a lower physiological P use efficiency at high P level. Alfalfa forage yield and water use efficiency increased with plastic film mulch. Soil water content in the upper 1 m of soil increased with plastic film mulch and was higher in the 2014 growing season and in April 2015 due to more rainfall. However, at 1–5 m soil depth, the soil water content decreased with plastic film mulch and P fertilization but increased at high P levels with plastic film mulch. Soil pH decreased with plastic film mulch and P fertilization, with a stronger effect from the latter, which is beneficial for improving soil P availability. Soil available P, mostly derived from inorganic P, increased with P fertilization and was lower in M than NM treatments due to alfalfa uptake and competition with soil microorganisms. We concluded that plastic film mulch and P fertilization, of about 16.1 or 17.5 kg P ha−1, was an appropriate combination to improve soil water condition and soil P availability for increased alfalfa forage yield or shoot P uptake in this semiarid region.

Permanent raised beds (PB) are a conservation agriculture option for irrigated conditions that can improve soil quality, increase soil moisture conservation and stabilize yields compared to conventional furrow irrigation. In irrigated wheat (Triticum sp.) production, wet sowing (i.e. applying irrigation before sowing) is most widely used. It allows pre-sowing weed control but reduces sowing time flexibility. Dry sowing, i.e. applying irrigation after sowing, reduces options for weed control but improves water use efficiency and sowing time flexibility. This study evaluated the performance of durum wheat (Triticum durum L.) under conventionally tilled (CTB) and PB with wet and dry sowing in northwestern Mexico. In those four tillage-sowing irrigation environments (ENV), five nitrogen (N) fertilization treatments were tested. Plant stand, grain yield, and grain quality were measured for ten years and fertilizer-based N use efficiency indices were assessed in three years. Plant stand, wheat yield and quality were significantly affected by ENV. The lowest plant stand and yield were found in PB-Dry sowing. On average, only 54 plants m-2 emerged in PB-Dry whereas 159 plants m-2 emerged in CTB-Wet. Plant stand showed high yearly fluctuations, with plant stand in dry sowing favored by lower reference evapotranspiration, with CTB-Dry favored more by high minimum temperature and PB-Dry by high maximum temperature. Yield ranged between 4.20 and 7.94 t ha-1. Yield in PB-Dry was on average 0.35 to 0.50 t ha-1 lower than in the remaining ENV, but positive interactions between year and dry sowing systems were associated with high minimum temperatures at germination and tillering. N fertilization management affected wheat quality, but not wheat yield, possibly due to high levels of soil mineral N available at sowing that were not measured in this study. Split application of N increased grain N content compared to basal N application. Research should address reduced plant stands with dry sowing in conservation agriculture to find management options that improve wheat emergence. Further efforts to optimize N fertilizer management in PB are required to improve grain quality components.

The Environmental Policy Integrated Climate (EPIC) model was used to assess the impacts of climate change and proposed adaptation measures on yields of corn ( Zea mays L.) and soybean ( Glycine max L.) as well as aggregated yields of C 3 [soybean, alfalfa ( Medicago sativa L.), winter wheat ( Triticum aestivum L.)] and C 4 [corn, sorghum ( Sorghum bicolor L.), pearl millet ( Pennisetum glaucum L.)] crop types from representative farms in ten Southeastern US states. Adaptations included annual biochar applications and irrigation. Historical baseline (1979–2009) and future (2041–2070) climate scenarios were used for simulations with baseline and future CO 2 concentrations of 360 ppmv and 500 ppmv, respectively. Four regional climate models (RCMs) nested within global climate models (GCMs) were used to run future simulations. The experiment was analyzed as randomized complete block design with split-plots in time for baseline vs. future comparisons, and as a randomized complete block design with repeated measures for comparisons between future periods within each RCM_GCM model. Compared to historical baseline scenario, increases in future corn yield ranged between 36–83%, but yields decreased by 5–13% towards 2066–2070 due to temperature stress. Future soybean yields decreased by 1–13% due to temperature and moisture stresses. Future aggregated C 4 crops produced higher yields compared to historical C 4 yields. There were no differences between future aggregated and historical C 3 crop yields. Both crop types were negatively affected by progressing climate change impacts towards the end of 2066–2070 simulation period. Reductions in future aggregated C 3 crop yields ranged between 10–22%, and between 6–10% for C 4 crops. We explained lower reductions in C 4 compared to C 3 crops due to a lesser degree of photorespiration, better water use efficiency, and better heat tolerance under conditions of high light intensities and increased temperatures in C 4 crops. Irrigation resulted in increased future corn yields between 29–33%, and 3–38% of aggregated C 4 crop yields, with no effect on soybean or aggregated C 3 crop yields. In some regions, biochar applications caused significant yield reductions of 9.5–20% for corn, 5–7% for aggregated C 3 , and 3–5% for aggregated C 4 crops, depending on the model. Yield reductions were ascribed to alterations in plant nutrient availability. It was concluded that under drier weather scenarios, irrigation may be a promising adaptation strategy for agriculture in the Southeastern US.

Land use conversion of row crops to bioenergy cropping systems in the southeastern United States (U.S.) creates concerns associated with water use and NO 3 -N leaching. Production of energy from biomass is associated with large amounts of byproducts generated during biofuel processing. Biochar and vinasse are two nutrient rich byproducts that could be land-applied to bioenergy crops to reduce reliance on synthetic fertilizer. However, effects on water dynamics of applying these byproducts to support biomass production is poorly understood, particularly when bioenergy crops replace traditional row crops. Thus, this study aimed to compare a cotton ( Gossypium hirsutum L.)-peanut ( Arachis hypogaea L.) rotation to sweet sorghum [ Sorghum bicolor (L.) Moench] receiving annual applications of biochar and vinasse, on biomass yield, crop evapotranspiration, water use efficiency (WUE), NO 3 -N leaching, and soil volumetric water content. A field study was conducted from 2013 to 2015 to assess the following treatments: cotton + 150 kg N ha −1 (COT), peanut + 30 kg N ha −1 (PEA), and sweet sorghum receiving one of the following i) 30 kg N ha −1 (S30); ii) 30 kg N ha −1 + biochar (S30B); iii) 30 kg N ha −1 + vinasse (S30V); and iv) 150 kg N ha −1 (S150). Similar aboveground dry matter yields were obtained in 2013 and 2015 for cotton and all sweet sorghum treatments and were on average 19 Mg ha −1 for both years. S30 and S150 achieved similar yields. Sweet sorghum and COT exhibited the highest WUE (∼5 g kg −1 ). S30B increased soil moisture retention at 0–0.2 m depth 36, 29, and 24% in 2013, 2014, and 2015, respectively. Biochar incorporated at 0.15 m soil depth increased soil moisture retention down to 0.4 m. Low N rate application combined with biochar in S30B could represent an alternative management practice to minimize N leaching, recycle nutrients, and increase soil water retention if sweet sorghum were to be widely adopted by farmers in the southeastern U.S.

Film-mulched drip irrigation as an effective water saving irrigation method has been widely utilized in arid areas. Unnecessary soil-water loss and excessive salt accumulation from soil evaporation, however, still occur in the bare strips between adjacent films under drip irrigation so that developing a useful method to combat this has been a challenge. Applying the methods of soil evaporation control in the bare strips under film-mulched drip irrigation may alleviate this problem. In 2013 and 2014, we thus adopted four controlling methods (STM: straw mulching, SAM: sand mulching, PAM: polyacrylamide amendment application, and CSS: surface soil compaction) in bare strips to evaluate their effects on soil properties and cotton productivity under film-mulched drip irrigation in southern Xinjiang, northwestern China. The main results showed that the four controlling methods gave more stable daily soil temperatures in bare strips with respect to CK. In general, STM and PAM reduced the soil temperature while CSS and SAM increased it. Moreover, the four controlling methods effectively reduced daily soil evaporation by 34.6–96.2% and 61.1–77.3% in 2013 and 2014, respectively. Lower evapotranspiration was found in the four controlling methods. The salt accumulation amount from late seedling stage to harvest reduced greatly in the four controlling methods, especially in STM and PAM. There were no significant differences in cotton yield and water-use efficiency (WUE), but the WUE for the four controlling methods slightly increased by 10.2–12.2% and 1.1–8.5% in 2013 and 2014, respectively, with respect to CK. The highest yield and WUE were found in SAM during the both seasons, indicating that SAM could be more effective than the other controlling methods at the experimental site. The controlling methods in bare strips under film-mulched drip irrigation can provide an alternative option to prevent the risk of soil salinization and enhance crop productivity in the arid regions of Xinjiang and other similar regions in the world. However, long-term use of the controlling methods in bare strips under film-mulched drip irrigation should be further evaluated.

The reliance of current farming systems on synthetic fertilizers caused concerns about their sustainability, and alternatives to supply nitrogen through biological processes have to be adapted to practical conditions. The present study compared a pure legume and legume-grass biculture as cover crops for sorghum in their supply of nitrogen (N) to the cash crop and their N leaching losses during fallow. A three-year field experiment under no-till with sorghum (Sorghum bicolor Moench.) as main crop and cover crop treatments (C- control = bare fallow; R-rye Secale cereale L.; V-vetch Vicia villosa sp dasycarpa; VR-vetch-rye biculture) was established with a completely randomized block design (four replicates) in semiarid central Argentina. Aerial biomass (AB) and N contents were determined for all crops. Soil moisture to 1 m and nitrate-N to 0.60 m depth were determined. Water use- and nitrogen use efficiencies (WUE and NUE) were calculated and biological nitrogen fixation (BNF) estimated. BNF depended on nitrate-N contents of the soils; highest values (11 and 10 g BNF m−2 for V and VR respectively) were reached at 1.3 g N m−2. Sorghum responded to higher N availability with an average of +299 and +512 g AB m−2 for V and VR compared to C, with higher WUE. The relationship between WUE and nitrate-N was positive with an optimum of 0.048 g N m−2 mm −1 where WUE reached a maximum of 4.9 g AB m−2 mm−1. Potential N losses by leaching were highest in control, while all cover crop treatments had lower losses. Our results support the hypothesis that a legume-grass biculture was more efficient in the trade-off between nitrogen provision to the cash crop and prevention of N losses by leaching. Although the amount of BNF was lower in the biculture than in pure vetch, it covered sorghum N requirements with less potential leaching losses even in high rainfall fallows.

The winter wheat ( Triticum aestivum L.) production of the North China Plain is threatened by increasing water shortages. Therefore, the invention of effective irrigation techniques is crucial to maintain high yields of winter wheat through improved water use efficiency (WUE). In this study, field experiments were carried out in the North China Plain region in 2012–2013 and 2013–2014. Based on the soil moisture regulation at sowing to ensure the normal emergence of the winter wheat, four supplemental irrigation (SI) regimes were set up: no-irrigation after emergence (T1), SI at jointing and anthesis (T2), SI at sowing, jointing and anthesis (T3), and SI at pre-wintering, jointing and anthesis (T4). The results showed that the root length density (RLD), root surface area density (RAD), and root weight density (RWD) in the 0–0.2 m soil layer from T2 increased rapidly after jointing and were significantly higher than those from T3 and T4 at anthesis. Those of T2 in the 0.6–0.8 m and 0.8–1.0 m soil layers were also significantly higher at anthesis. T2 was significantly higher than T1 in the photosynthetic rate (P n ) and instantaneous water use efficiency (WUE leaf ) of flag leaves, post-anthesis dry matter accumulation (DMA), contribution of DMA to grain (CDMA), grain yield and WUE, but lower than T1 in the pre-anthesis dry matter remobilization efficiency (DMRE) and contribution of DMR to grain (CDMR). T2 had significantly lower plant populations and dry matter at jointing, P n and WUE leaf at 28 days after anthesis, DMA and CDMA, but higher dry matter increase rate after jointing, tiller survival rate, DMR, DMRE, CDMR and WUE. The combined effect of these differences enabled T2 to have yield that was not significantly different to T4. In summary, SI at joining and anthesis that was based on suitable soil water content at sowing increased the absorbing area of roots in both deep and surface soil layers; accelerated the dry matter accumulation after jointing; increased the P n and WUE leaf of flag leaves, DMA and DMR; and finally achieved a high grain yield and higher WUE. However, excessive irrigation reduced the WUE by inhibiting the redistribution of dry matter, although the WUE leaf of flag leaves was still increased.

Arbuscular mycorrhizal (AM) fungi and biochar have been successfully adopted to improve crop growth and yield under water stressed environments, however, to date little evidence of their combined effects has been reported. Field trials were conducted in 2018 and 2019 growing seasons in northern Iran to evaluate how biochar and AM fungi could improve sunflower (Helianthus annuus L.) productivity subjected to reduced irrigation regimes. A randomized complete block design was adopted with the following treatments: three irrigation regimes [no deficit irrigation (NDI), moderate deficit irrigation (MDI) and severe deficit irrigation (SDI) that was calculated as the 50, 30, and 10 % of maximum available water, respectively]; three biochar rates [0 (B0), 2.5 (B2.5) and 5 (B5) t ha−1 of biochar]; and two AM fungi inoculations [inoculated (AM+) and no-inoculated (AM-) plants]. All treatments were replicated three times. Before plowing, biochar (B2.5 and B5) was uniformly distributed on the soil surface to incorporate in the soil profile, while AM fungi (AM+) were distributed in the furrow of sunflower rows before sowing. Biochar and AM fungi were not applied in B0 and AM- treatments, respectively. Sunflower growth rate, pigments, photosynthesis rate and associated aspects, minerals content, antioxidant enzymes, abscisic acid, total phenolics and seed yield were measured. The results showed that growth parameters, radiation use efficiency, leaf pigments and seed yield decreased under irrigation regimes (NDI > MDI > SDI), while malondialdehyde (MDA) and hydrogen peroxide (H2O2) showed opposite trends. The combination AM fungi and biochar enhanced antioxidant enzymes activities, osmoprotectants, nutrient content and relative water content resulting in a significant decrease in oxidative damage in the drought stressed plants. Seed yield ranged from 4.95 to 1.78 t ha−1 and it was increased by the biochar application (+9% and +7% in B2.5 and B5, respectively) and AM fungi inoculation (+21 % in AM+) in all irrigation regimes. Overall, the plant's performance observed in the MDI-B5-AM+ was similar to that in NDI-B0-AM- indicating that AM fungi and biochar allow a reduction of water irrigation while maintaining crop yield. According to results, the combination of AM fungi and biochar rate should be adopted as a water-saving practice for sustainable production of sunflower cultivated in semi-arid environments, even if further studies should be carried out to evaluate their effects on other crops and environments.

Present study is the first to report the ecosystem CO2, H2O and energy exchanges (at diurnal, daily and seasonal-scale) from rainfed winter chickpea crop (Cicer arietinum L.), grown under residual soil moisture over semi-arid peninsular India, using eddy covariance system. The available energy to the ecosystem was found to be predominantly partitioned into sensible heat flux (H), except during the peak vegetative stage. Asymmetric response of the daytime (forenoon and afternoon) CO2 and energy fluxes were observed due to limited soil moisture condition. The peak vegetative stage of the crop i.e., 40–60 Days after Sowing (DAS) showed highest rate of Net Ecosystem CO2 Exchange (NEE; −9 to −11 μmol m−2 s−1) and Latent Heat Flux (LE; ∼ 300 W m−2). The response of daytime Gross Primary Production (GPP) to light intensity was found to be poor during 1–16 DAS, improved steadily in 17−34 DAS, remained high in 35–69 DAS, and deteriorated thereafter till harvesting (70–106 DAS). The chickpea crop was net CO2 sink on daily basis during 17–69 DAS. Peak daily NEE of −2.52 gC m−2 day−1, GPP of 4.2 gC m−2 day-1 and Evapotranspiration (ET) of 2.38 mm day−1 were observed during the growing season. Over the entire season, rainfed chickpea was found to be a weak carbon sink with cumulative NEE of -32.39 ± 4.21 gC m−2; GPP of 163.03 ± 15.04 gC m−2; Ecosystem Respiration (Reco) of 127.45 ± 12.85 gC m−2; ET of 177 ± 18.13 mm. The maximum ecosystem water use efficiency (GPP/ET) and crop coefficient were found to be 1.7 gC m−2 mm−1 and 0.6 respectively at peak vegetative stage, which are sub-optimal compared to well managed chickpea crop. The results help us to understand the ecosystem processes and exchanges from rainfed winter legume-based cropping system, which intern would significantly contribute in global carbon and moisture budget.