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In the production of economic forests, there are common issues such as excessive application of water and fertilizer, redundant plant growth, and low economic benefits. Reasonable water and fertilizer management can not only help address these problems but also improve the absorption and use efficiency of water and fertilizer resources by plants, promoting the green and efficient development of the fruit and forestry industry. In order to explore a suitable water and nitrogen management mode for Lycium barbarum, field experiments were conducted in this study from 2021 to 2022. Specifically, four irrigation modes (according to the proportion ratio of soil moisture content to field moisture capacity θf, 45–55% θf (W1, severe water deficiency), 55–65% θf (W2, moderate water deficiency), 65–75% θf (W3, mild water deficiency), and 75–85% θf (W4, sufficient irrigation)) and four nitrogen application levels (0 kg·ha−1 (N0, no nitrogen application), 150 kg·ha−1 (N1, low nitrogen application level), 300 kg·ha−1 (N2, medium nitrogen application level), and 450 kg·ha−1 (N3, high nitrogen application level)) were set up to analyze the influences of water and nitrogen control on the plant height, stem diameter, chlorophyll content, photosynthetic characteristics and yield, and economic benefits of Lycium barbarum in the Lycium barbarum + Alfalfa system. The study results show that the plant height and stem diameter increment of Lycium barbarum increase with the irrigation amount, increasing first and then decreasing with the increase in the nitrogen application level. Meanwhile, the chlorophyll contents in Lycium barbarum continuously increase throughout their growth periods, with Lycium barbarum treated with W4N2 during all growth periods presenting the highest contents of chlorophyll. In a Lycium barbarum + Alfalfa system, the daily variation curve of the Lycium barbarum net photosynthetic rate presents a unimodal pattern, with maximum values of the daily average net photosynthetic rate and daily carboxylation rate appearing among W4N2-treated plants (19.56 μmol·m−2·s−1 and 157.06 mmol·m−2·s−1). Meanwhile, the transpiration rates of Lycium barbarum plants continuously decrease with the increased degree of water deficiency and decreased nitrogen application level. W1N2-treated plants exhibit the highest leaf daily average water use efficiency (3.31 μmol·s−1), presenting an increase of 0.50–10.47% in efficiency compared with plants under other treatments. The coupling of water and nitrogen has significantly improved the yields and economic benefits of Lycium barbarum plants, with W4N2-treated and W3N2-treated plants presenting the highest dried fruit yield (2623.07 kg·ha−1) and net income (50,700 CNY·ha−1), respectively. Furthermore, compared with other treatment methods, these two treatment methods (W4N2 and W3N2) exhibit increases of 4.04–84.08% and 3.89–123.35% in dried fruit yield and net income indexes, respectively. Regression analysis shows that, in a Lycium barbarum + Alfalfa system, both high yields and economic benefits of Lycium barbarum plants can be achieved using an irrigation amount of 4367.33–4415.07 m3·ha−1 and a nitrogen application level of 339.80–367.35 kg·ha−1. This study can provide a reference for improving the productivity of Lycium barbarum plants and achieving a rational supply of water and nitrogen in Lyciun barbarum + Alfalfa systems in the Yellow River Irrigation Area of Gansu, China, and other similar ecological areas. [ABSTRACT FROM AUTHOR]

Establishing lucerne field is an efficient way to protect natural steppes, alleviate conflicts between meadows and livestock, and promote the development of animal husbandry. However, problems such as extensive field management, valuing yield over quality, and low resource utilization are endemic in production. Exploring reasonable cultivation patterns can contribute to improving the current situation of artificial grassland production and promoting the high-quality development of husbandry and prataculture. Lucerne the field experiment was carried out in Jingtai, Gansu Province, China in 2021–2022; this study compared and analyzed the effects of three cultivation patterns—ridge tillage with plastic film mulching (PM), ridge tillage with biodegradable film mulching (BM), and traditional flat planting (FP)—on soil water, heat, and fertilizer, as well as lucerne growth, yield, quality, and water and nitrogen use efficiency. The results show that: (1) during the growth period of lucerne, PM and BM treatments augment the average moisture content of the soil layer of 0–120 cm by 31.19% and 24.03% compared to the FP treatment, respectively. In the soil layer of 0–40 cm, PM and BM treatments abate the soil moisture content of the ridges by an average of 19.29% and 7.89% compared to that in the ditches, respectively. In the soil layer of 40–120 cm, PM and BM treatments elevate the soil moisture content of the ridges by 4.40% and 4.65% on average compared to that in the ditches, respectively. The average soil temperature in a soil layer of 5–25 cm shows PM > BM > FP. In contrast with the FP treatment, PM and BM treatments increase the soil temperature of the ridges by an average of 1.87 °C and 0.96 °C and decrease that of the ditches by an average of 0.47 °C and 0.46 °C, respectively. After two years of planting, the three cultivation patterns all promote the soil nutrient content. Compared to the FP treatment, PM and BM treatments increase the organic matter content by 9.94% and 19.94%, respectively. (2) Ridge tillage with film mulching can evidently stimulate the growth of lucerne and enhance yield and quality. Compared to the FP treatment, PM and BM treatments enhance plant height by an average of 15.37% and 4.04%, stem diameter by an average of 34.14% and 14.58%, yield by an average of 21.20% and 14.77%, crude protein content by an average of 13.47% and 7.68%, and relative feed value by an average of 8.71% and 4.41%, respectively. (3) During the two-year growing period, the irrigation amount of lucerne was 508.60–615.30 mm, and the evapotranspiration was 563.70–761.80 mm. Compared to the FP treatment, PM and BM treatments hoist water use efficiency by an average of 43.50% and 17.56%, nitrogen partial factor productivity by an average of 21.20% and 15.22%, and net income by an average of 14.78% and 11.05%, respectively. In summary, in ridge tillage, both ordinary film mulching and biodegradable film mulching can create a favorable soil environment for lucerne growth and heighten production effect. The former has a better effect on advancing the lucerne production effect, and the latter exhibits superior performance in improving soil fertility. [ABSTRACT FROM AUTHOR]

Wolfberry (Lycium barbarum L.) production in arid and semi-arid areas is drastically affected by the low utilization rate of soil and water resources and the irrational application of water and nitrogen fertilizers. Thus, this study explored a high-yielding, high-quality, and efficient irrigation and nitrogen regulation model to promote the production efficiency of wolfberry and rational utilization of water and land resources in arid and semi-arid areas. We compared and analyzed the effects of different soil water treatments (the upper and lower limits of soil water were estimated as the percentage of soil water content to field water capacity (θf), with the following irrigation regimen: adequate irrigation (W0, 75–85% θf), mild water deficit (W1, 65–75% θf), moderate water deficit (W2, 55–65% θf), and severe water deficit (W3, 45–55% θf)) and nitrogen levels (no nitrogen (N0, 0 kg·ha−1), low nitrogen (N1, 150 kg·ha−1), moderate nitrogen (N2, 300 kg·ha−1), and high nitrogen (N3, 450 kg·ha−1)) on the growth, physiology, and production of wolfberry. The results showed that water regulation, nitrogen application level, and their interaction significantly affected plant height and stem diameter growth amount (p < 0.05). Additionally, the relative chlorophyll content of wolfberry leaves first increased and then decreased with increasing nitrogen levels and water deficit. The average net photosynthetic rate (Pn), stomatal conductance (gs), intercellular carbon dioxide concentration, and transpiration rate (Tr) reached the highest values in plants exposed to W0N2 (19.86 μmmol·m−2·s−1), W1N1 (182.65 mmol·m−2·s−1), W2N2 (218.86 μmol·mol−1), and W0N2 (6.44 mmol·m−2·s−1) treatments, respectively. Pn, gs, and Tr were highly correlated with photosynthetically active radiation and water vapor pressure difference (goodness-of-fit: 0.366–0.828). Furthermore, water regulation and nitrogen levels exhibited significant effects on the yield and water- (WUE), and nitrogen-use efficiency (NUE) (p < 0.01), and their interactions exhibited significant effects on the yield, WUE, and nitrogen partial productivity of wolfberry plants (p < 0.05). Moreover, the contents of total sugar, polysaccharides, fats, amino acids, and proteins were the highest in W1N2, W1N2, W1N2, W2N3, and W0N2 treatments, respectively, which were increased by 3.32–16.93%, 7.49–54.72%, 6.5–45.89%, 11.12–86.16%, and 7.15–71.67%, respectively. Under different water regulations (except for the W3 condition) and nitrogen level treatments, the net income and input–output ratio of wolfberry were in the order W1 > W0 > W2 > W3 and N2 > N3 > N1 > N0. The TOPSIS method also revealed that the yield, quality, WUE, NUE, and economic benefits of wolfberry improved under the W1N2 treatment, suggesting that WIN2 might be the most suitable irrigation and nitrogen regulation model for wolfberry production in regions with scarce land and water resources such as the Gansu Province and areas with similar climate. [ABSTRACT FROM AUTHOR]

Identifying the evolutionary patterns and drivers of regional water use is a prerequisite for achieving the strictest water resource management system. This study used the Tapio-LMDI model to analyze the decoupling state and driving factors between economic development and production water use in Jiangsu Province from 2004 to 2020. The results show that: (1) From the evolution of the water use structure, the total water use in Jiangsu Province shows a decreasing trend from 2004 to 2020. Among them, the production water use decreased by 9.59%. From the characteristics of economic development (constant prices), the growth of Jiangsu's gross regional product (GDP) from 2004 to 2020 reached 363%. (2) In terms of the decoupling status, economic development and production water use in Jiangsu Province underwent a "weak decoupling—strongly decoupling" transition and achieved "strongly decoupling" in 2020, with a decoupling elasticity coefficient of −2.30. (3) From the perspective of the decoupling drivers, the reduction in production effects has contributed to the decoupling between economic growth and water use in Jiangsu Province. By sector, the decline in the water use intensity effect and the industrial structure effect in the primary and secondary sectors were the main reason for the decline in its water use, while the increase in the industrial structure effect and economic scale effect of the tertiary sector has effectively contributed to the increase in water use in the tertiary sector. Therefore, there is an urgent need to improve the water use efficiency of the primary and secondary sectors, accelerate the transformation and upgrading of the tertiary sector, and realize a "strongly decoupling" pattern between economic development and production water use in Jiangsu Province. [ABSTRACT FROM AUTHOR]

Scientific selection of appropriate herbage planting management mode is an important guarantee to promote artificial grassland development and grassland productivity. In this study, three-year-old alfalfa (Medicago sativa L.) and bromus inermis were applied to analyze the effects of planting patterns (bromus inermis and alfalfa mixed-sowing D1, bromus inermis mono-sowing D2), nitrogen application (pure nitrogen) level (N1: 60 kg·ha−1, N2: 120 kg·ha−1), and water regulation (upper and lower limits of irrigation are calculated as a percentage of field capacity θf, W1: slight water deficit 65~85% θf, W2: moderate water deficit 55~85% θf, W3: serious water deficit 45~85% θf) on herbage growth and water-nitrogen use efficiency. This research applied the principal component analysis, the TOPSIS model, and the combination evaluation to evaluate each treatment. Results demonstrated that (1) the plant height, leaf area index, and yield of mixed-sowing herbage were 81.63%, 119.52%, and 111.51%, higher than the mono-sowing herbage. Increasing the amount of irrigation and nitrogen application could enhance herbage yield. The herbage yield with the W1N2 treatment was the highest. In this treatment, the mixed-sowing herbage yield was 26,050.73 kg·ha−1, and the mono-sowing herbage yield was 12,186.10 kg·ha−1. (2) The crude protein content of mixed-sowing herbage increased by 41.44%, higher than mono-sowing herbage, and the relative feeding value decreased by 16.34%. Increasing irrigation and nitrogen application could improve the quality of herbage. Meanwhile, the quality of herbage treated with W1N2 was the best. (3) The water use efficiency (WUE), irrigation water use efficiency (IWUE), partial factor productivity of nitrogen (PFPN), and crude protein water use efficiency (CPWUE) of mixed-sowing herbage were significantly higher than mono-sowing herbage. The PFPN and the CPWUE of herbage improved with increasing irrigation amount. Meanwhile, the WUE, the IWUE, and the CPWUE of herbage also improved with increasing nitrogen application amount. The results showed that mixed-sowing of alfalfa and bromus inermis with slight water deficit (upper and lower limit of irrigation was 65~85% θf) and nitrogen application (120 kg·ha−1) could have the best comprehensive production effect. At the same time, it was a planting and management mode of high yield, high quality, and high efficiency of artificial herbage in the oasis-desert interlacing area of Hexi, Gansu Province, China, and areas with similar climates. [ABSTRACT FROM AUTHOR]

This study was about the water-nitrogen regulation model and its soil nutrient environment effect for increasing the yield and efficiency of Bromus inermis in the Hexi Corridor, Gansu Province, China. Bromus inermis was used as the research object in this study and four irrigation management types and four nitrogen application levels were set. The four irrigation management types (controlled by the percentage of field capacity (θf) at the jointing stage) were 75–85% (W0), 65–85% (W1), 55–85% (W2) and 45–85% (W3). The four nitrogen application levels were pure nitrogen 0 kg·ha−1 (N0), 60 kg·ha−1 (N1), 120 kg·ha−1 (N2) and 180 kg·ha−1 (N3). The effects of water-nitrogen regulation on the spatial and temporal distribution of soil moisture and nitrate nitrogen (NO3−–N), plant height, chlorophyll content, yield and water-nitrogen use efficiency of Bromus inermis were studied. Results demonstrated that (1) soil water content (SWC) was mainly affected by irrigation and W1 treatment helped maintain shallow soil (0–40 cm) water's stability and avoided water redundancy or deficit in the 60–80 cm soil layer. The distribution of soil NO3−–N was mainly affected by nitrogen application. The N2 treatment could effectively increase the NO3−–N content in shallow soil (0–40 cm) and prevent nitrate-nitrogen leaching in the 60–100 cm soil layer. (2) Irrigation and nitrogen application could significantly increase the plant height and chlorophyll content of each cut of Bromus inermis. The average plant height and chlorophyll content of the N2W1 treatment were 66.99% and 30.30% higher than N0W3. (3) At the same time, irrigation and nitrogen application could significantly increase the yield of each cut of Bromus inermis, and the interaction between the two had a significant effect on the total yield. The total yield of the N2W1 treatment was the highest (12,259.54 kg·ha−1), 157.95% higher than N0W3. Irrigation and nitrogen application could significantly improve the water-nitrogen use efficiency of Bromus inermis, and their interaction only significantly impacted the partial-factor productivity of the applied nitrogen (PFPN). Meanwhile, the N2W2 treatment had the highest water use efficiency (WUE) (23.12 kg·m−3), and the N1W1 treatment had the highest PFPN (170.87 kg·kg−1). In summary, the moderate nitrogen application rate (120 kg·ha−1) combined with mild water deficit (65–85% θf at the jointing stage) could not only promote the high yield of Bromus inermis, but also avoid the leaching of water and nitrogen in deep soil. It is a suitable water and nitrogen management mode for Bromus inermis in the Hexi Corridor of Gansu Province, China. [ABSTRACT FROM AUTHOR]

Appropriate planting and nitrogen application patterns to support high-quality production of cultivated forage in light of issues of water scarcity, extensive field husbandry, and low productivity in cultivated grassland planting areas were investigated in this study. Using Medicago sativa L. (alfalfa) as the research object, this study analyzed the effects of planting patterns (conventional flat planting (FP) and ridge culture with film mulching (RM)) and nitrogen level (N0: 0 kg·ha−1, N1: 80 kg·ha−1, N2: 160 kg·ha−1, N3: 240 kg·ha−1) on the growth, yield, quality (crude protein content (CP), acid detergent fiber content (ADF), neutral detergent fiber content (NDF), and relative feeding value (RFV)), the water–nitrogen use efficiency, and economic benefits (EB) of alfalfa in the year of establishment. Results demonstrated that (1) RM might greatly increase the growth of alfalfa when compared to FP. The plant height, stem diameter, and leaf:stem ratio of alfalfa all increased under the same planting patterns before decreasing as the nitrogen application rate (NAR) increased. (2) Appropriate NAR combined with RM could improve the yield and quality of alfalfa. Compared with other treatments, the yield, CP, and RFV under RMN2 treatment increased by 5.9~84.9%, 4.9~28.6%, and 19.6~49.3%, respectively, and the ADF and NDF decreased by 14.0~27.6% and 13.0~26.1%, respectively. (3) Under the same nitrogen level, RM showed better performance than FP in terms of water use efficiency (WUE), irrigation water use efficiency (IWUE), precipitation use efficiency (PUE), partial factor productivity of nitrogen (PFPN), agronomic nitrogen use efficiency (ANUE), and EB of alfalfa. Under the same planting pattern, PFPN decreased as the NAR increased, while WUE, IWUE, PUE, ANUE, and EB first increased and then decreased as the NAR increased and reached a maximum value under the N2 condition. In conclusion, the RM planting pattern combined with a nitrogen level of 160 kg·ha−1 can significantly promote alfalfa growth as well as the yield, quality, water–nitrogen use efficiency, and EB of alfalfa, making it a suitable planting management mode for alfalfa production in the Yellow River irrigation region in Gansu Province, China and areas with similar climate. [ABSTRACT FROM AUTHOR]