RESUMO
γ-polyglutamic acid (γ-PGA), as an environmentally sustainable material, is extensive applied in agriculture for enhancing water and fertilizer utilization efficiency, augmenting crop yield, and ameliorating soil conditions. However, the effect of γ-PGA in conjunction with sesame cake fertilizer on the soil environment remains uncertain.The aim of this study is to investigate the effect of γ-PGA on soil nutrients, water use efficiency (WUE) and nitrogen use efficiency (NUE), and maize yield across various levels of sesame cake fertilizer. Additionally, the study seeks to identify the optimal ratio to establish a theoretical and practical foundation for sustainable agricultural development and the promotion of ecological agriculture. Through field experiments, nine treatments were established, comprising three levels of sesame cake fertilizer application rates (B1 = 900 kg/hm2 for low fertility, B2 = 1100 kg/hm2 for medium fertility, and B3 = 1300 kg/hm2 for high fertility) and three levels of γ-PGA application rates (R1 = 200 kg/hm2, R2 = 400 kg/hm2, and R3 = 600 kg/hm2). The results can be outlined as follows: (1) When γ-PGA application rate increased, total nitrogen (TN) exhibited a synergistic effect under B1 treatment, but an antagonistic effect under B2 and B3 treatments. At the 6-leaf stage (V6), 12-leaf stage (V12), and tasseling stage (VT), available phosphorus (AP) exhibited antagonistic effects. However, at the filling stage (R2) and maturity stage (R6), AP in B1 and B2 treatments at various depths underwent partial transformation into a synergistic effect. The levels of available potassium exhibited a notable antagonistic effect, leading to a decrease in harvest index (HI). B2 treatment demonstrated superior results compared to the B1 and B3 treatments, with the highest levels observed under B2R1 treatment; (2) TN content in the 0-40 cm soil layer increased during the filling period, and it was uniformly distributed in the 40-60 cm soil layer. When the soil AP was located in the 0-60 cm soil layer, there was an increase in AP content during the mature period. Following the tasseling period, different treatments exhibited varying patterns of increase in response to the presence of potassium within the 0-60 cm soil layer. Consequently, in cases where the sesame cake fertilizer content is low, the interaction between γ-PGA can compensate for the deficiency of fertilizer, thereby enhancing water and nitrogen utilization efficiency. The optimal fertilization strategy for enhancing soil nutrient distribution, WUE and NUE, and yield is proposed to be the application of 1100 kg/hm2 sesame cake fertilizer and 200 kg/hm2 γ-PGA.
RESUMO
The Yellow River Basin is one of the most important economic development belt and ecological management regions in China, it is of vital importance to study the coupling coordination between ecological protection and high-quality development. However, the systematic research from the perspective of ecological-production-living is still lacking. Therefore, a comprehensive evaluation index system including 29 indicators is constructed from ecological, production and living dimension. To evaluate the high-quality development level and coupling coordination degree of 61 cities in the Yellow River Basin, a comprehensive measurement model and coupling coordination model are established using the entropy weight TOPSIS method. With the help of ArcGIS, the spatial characteristics of high-quality development level and coupling coordination are visually illustrated. The results showed that: (1) From 2011 to 2020, the high-quality development of 61cities in the Yellow River Basin showed an increasing trend, and the level of upper and lower reaches was higher than that of the middle reaches. (2) According to the high-quality development level of 61 cities, it was divided into three types: sustainable growth type with 44 cities, the fierce fluctuation type with 11 cities and the other 6 cities was stable type. (3) The coupling coordination degree of ecology, production and living system also showed an increasing trend, while the degree was not high. (4)About the year-on-year growth rate of coupling coordination degree for 61 cities in 2020 compared with 2011, there are 19 cities more than 30 %, and 23 cities between 20% and 30 %, 11cities was 10%-20 %, the other 8 cities was less than 10 %. (5) There is a significant spatial difference in the level of high-quality development in the Yellow River Basin, while coupling coordination degree does not significant in spatial layout. Therefore, the development of different regions should adjust measures to local conditions, give full play to their advantages, and make up for their shortcomings to promote the overall development of the city.