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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]

Measuring the carrying capacity of water resources and identifying obstacle factors are critical prerequisites for the rational allocation of regional water resources and the high-quality development of economic society. This study took Longnan City, a typical city in northwest China with abundant water resources but an underdeveloped economy, as the research object. Based on the DPSR (Driving–Pressure–State–Response), an evaluation indicator system was constructed. TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) and an obstacle model were used to calculate the water resource carrying capacity and main obstacle factors of Longnan City from 2009 to 2019. The results showed that the carrying capacity of water resources in Longnan City had steadily improved, and the comprehensive closeness had increased from 0.44 (2009) to 0.60 (2019). From the perspective of the ruler layer, the carrying capacity of the driving force system increased from 0.05 in 2009 to 1.00 in 2019. The capacity of the state system increased during the change, with the highest value (0.85) appearing in 2013 and the lowest value appearing in 2016. All subsystems, except the pressure system, had a load-carrying capacity of 0.60 or more in 2019. The utilization of unconventional water resources, the proportion of eco-environmental water use, the volume of wastewater discharge, and the per capita urban daily water consumption are the primary factors affecting the water resource carrying capacity of Longnan City. Developing unconventional water sources, improving sewage treatment technology, promoting efficient water-saving technology, and strengthening environmental protection is the key to improving the water resources carrying capacity of Longnan City. This research provides the basis for enhancing the carrying capacity of water resources and sustainable urban development in Longnan City and other cities in China and water scarcity cities in other countries. [ABSTRACT FROM AUTHOR]

Characteristics of temporal-spatial potential evapotranspiration (ET0) distribution in Gansu Province were studied based on the Cloud model, which is a mathematical representation of qualitative concepts including expected value Ex, entropy En and hyper entropy He, integrates the fuzziness and randomness of qualitative concept in a unified way, and is a new method for the transformation between the qualitative and the quantitative. The values of ET0 were calculated by Penman-Monteith. The changes of ET0 in time were analyzed at monthly, seasonal and yearly intervals, respectively, and spatial changes were mainly divided into 4 parts: Hexi area, the middle, east and south area of Gansu. All data of 63 years (1951-2013) were collected at 29 meteorological stations involving the above districts in Gansu. All ET0 data were achieved by the soft Interactive data language. The indices of homogeneity and stability were used for reflecting characteristics of temporal-spatial distribution of ET0, which were achieved by Cloud mode, solving the uncertain conversion of qualitative concept and quantitative description. And the changes of ET0 in time (monthly, seaonal and annual) and space were analyzed by the linear change and the contour image. The results showed annual variation in ET0 had a fluctuation and increasing tendency, and the tendency rate was 2.11 mm/(10a) in all study area (P<0.05). The monthly change curve of ET0 for 63 years was single apex type, which was: ET0 in June and July was higher than that in other months. In homogeneity and stability aspects of ET0, from November to March of the next year was better than from April to August in the same year. At the same time, there was significant difference on the distribution of ET0 among seasons, and the maximum was summer, followed by spring, and the least was autumn and winter. The further analysis found that both homogeneity and stability of temporal-spatial distribution of ET0 had no consistency among seasons. The homogeneity of ET0 in autumn and winter was higher than that in spring and summer, but the stability in summer and autumn was better than that in spring and winter. Seen from the difference characteristics of the space, ET0 in the northwest area of Gansu Province were larger than that in the southeast, however, the annual changes of ET0 among areas were different for 63 years. Concretely speaking, the value of annual ET0 in Hexi area was keeping the highest from 1951 to 2013. Seeing the changes of ET0 in the space using the homogeneity and stability, we found ET0 of Hexi area was most discrete and instable, the east area of Gansu had the best homogeneity and stability, and the middle and south were between them. The homogeneity and stability of ET0 in the space was worse than that in the time. Generally, the homogeneity of the distribution of ET0 was increasing since 1981, namely, the homogeneity from 1981 to 2013 was better than that from 1951 to 1981, and at the same time, the stability was also increasing for 63 years. [ABSTRACT FROM AUTHOR]