Sigmongriffith7736

73·(10 a)-1 in Northwest China, Gansu, Ningxia, Shanxi, Qinghai, and Xinjiang, respectively. The possibility of drought risk was higher in Xiaozaohuo, Korla, Aksu, and Turpan region. Precipitation and actual water vapor pressure were the dominant factors of AI changes in Gansu, Ningxia, Qinghai, and Shaanxi. But the potential evapotranspiration, solar radiation, and average temperature were the main climate factors for AI changes in Xinjiang.Exploring the spatial-temporal variations of agricultural eco-efficiency (AEE) and its driving factors is of vital importance to achieve high-quality agro-ecological development in China. In this study, we used the super efficiency slack-based measure (SBM) model to measure the inter-provincial AEE based on the relevant panel data of 30 provinces/regions/cities in China from 2000 to 2018. Based on the time series analysis, spatial visualization, and trend surface analysis, the geographical detector model was further used to identify the core factors driving the spatial-temporal variations of AEE. The results showed that China's AEE level maintained stable upward progress from 2000 to 2018, which was still at a low level with much room for improvement. The AEE in China exhibited a significant spatial-temporal variation, presenting higher levels in the eastern and western parts but lower in the central part. The spatial variation of AEE was influenced by many factors, including agricultural resource endowment, socioeconomic condition, and the natural ecological environment. There were obvious variations in the influence factors on the spatial-temporal variation of AEE. The interactions among factors would enhance the spatial variation of AEE. Therefore, due to the spatial-temporal variation of AEE, emphasis should be placed on its core driving factors as well as the inter-parts agricultural cooperation in order to achieve high-quality agro-ecological development in China.Understanding the spatiotemporal evolution characteristics of the risk of late frost damage has scientific guiding significance for optimizing the regional agricultural production layout and varie-ty tuning. Based on the daily meteorological data of 65 weather stations in the southwest China tea region from 1971 to 2020, we analyzed variation characteristics of the last frost date (LFD), tea bud open date (BOD), and their relationships, constructed frost damage probability index and frost damage severity index of spring shoots of shrubby tea trees, and analyzed the spatiotemporal evolution chara-cteristics of the late frost damage risk of shrub tea trees in the southwest tea region. The results showed that both the BOD and LFD had a significant ahead of trend from 1971 to 2020 and the early rate of the LFD was relatively faster than that of the BOD in the southwest tea region. The number of days that the tea buds were exposed to late frost damage after germination showed an non-significant declining trend. The risk of late frost damage of shrubby tea trees in most parts of the southwest tea region showed a declining trend, but Guizhou tea planting region showed an insignificant increasing trend. The risk of late frost damage to shrubby tea trees was high in the western marginal mountai-nous areas of Sichuan tea region, and the junction of Guizhou and Yunnan tea region. The risk of late frost damage was at low level in Sichuan Basin, southern Yunnan tea region, and southern Guizhou tea region. The risk of late frost damage to shrubby tea trees in the northern and central-eastern parts of Yunnan tea region showed an obvious decreasing trend, but increased significantly in the central and eastern parts of Guizhou tea region.Planting grasses in orchards is important to maintain soil basic fertility, improve the soil ecological environment, and promote sustainable growth of fruit. However, the quantitative effects of grasses on nutrient content of orchard soil in China is unclear, as well as the mechanisms associated with higher fruit yield and quality in orchards. This meta-analysis included 62 literature published between 1990 and 2020 to quantify effects of soil depth, planting years of raw grasses, and raw grasses to the physical and chemical properties and fruit yield and quality of orchards, as well as to explore the impacts of grasses on the sustainable production of Chinese orchards. Between 1990 and 2020, compared with the non-grass orchards, the content of soil organic matter, alkali nitrogen and available phosphorus in orchard with grasses increased by 18%, 11%, and 27% respectively, and the soil bulk density was reduced by 20%. Orchard grass increased soil temperature by 23% when the temperature was below 10 ℃, and reduced soil temperature by about 8% when the temperature was above 10 ℃. Compared with annual grasses, perennial grasses (natural or artificial) significantly improved soil properties, fruit yield and quality. These findings indicated that long-term grass planting in orchards had far-reaching significance on sustainable production.Soil phosphorus (P) could be categorized into organic and inorganic forms, with diffe-rent capabilities of nutrient supply. Exploring soil P components through liquid 31P-NMR would provide an important theoretical basis for soil P nutrition regulation. This study addressed the characteristic of P in alfalfa (Medicago sativa) soil via the pot experiment. There were two scenarios of treatments with conventional and dry water combined with different P fertilizer levels (P0-P4 0, 0.025, 0.05, 0.1, and 0.2 g P2O5·kg-1soil). The characteristics of P components in alfalfa soil under water-fertilizer coupling conditions were measured by liquid 31P-NMR. Results showed that under different water and fertilizer treatments, soil inorganic P was mainly composed of inorganic orthophosphate, pyrophosphate and inorganic polyphosphate. Inorganic orthophosphate was the dominant component of inorganic P, which could be reduced by drought. High P application (P4) could increase the contents of soil inorganic polyphosphates and inorganic pyrophosphates. Among the organic P components, monoester orthophosphate was dominant, the conversion and utilization of which in alfalfa soil were affected by drought. Overall, the rational management of water and fertilizer could effectively regulate the conversion and utilization of P nutrients in alfalfa soil in Eastern Inner Mongolia.Clarifying carbon and nitrogen emissions of different peanut rotation planting system can provide an effective reference to achieve high yield, high efficiency, and low carbon and nitrogen emissions. Based on field surveys on agricultural inputs and field managements, we calculated the carbon footprint and nitrogen footprint of three planting modes (rape-peanut rotation, wheat-peanut rotation and peanut monoculture) in Huanggang, Hubei Province. The results showed that compared with wheat-peanut rotation, carbon emission per unit area of rape-peanut rotation decreased by 7.8%, carbon emission per unit net present value decreased by 36.9%, the nitrogen emission per unit area decreased by 12.5%, and nitrogen emission per unit net present value decreased by 41.9%. Compared with peanut monoculture, rape-peanut rotation reduced carbon and nitrogen emissions by 19.6% and 30.8%, respectively. The net income of rape-peanut rotation was 1.4 times as that of wheat-peanut rotation and 2.4 times as that of peanut monoculture. It is suggested that rape-peanut rotation could achieve the synergistic benefits of high yield and efficiency and low carbon and nitrogen emissions, which is conducive to the green, high quality, and high efficiency production of oil crops.Saline-alkali stress is one of the common abiotic stresses for plants. selleck kinase inhibitor Hydrogen sulfide (H2S), as a gas signal, plays an important role in driving the responses of plants to saline-alkali stress. To explore the regulating effects of H2S on the ascorbate (AsA)-glutathione (GSH) cycle in naked oat (Avena nude) under saline-alkali stress, we used sodium hydrogen sulfide (NaHS) as donor of exogenous H2S and hydroxylamine (HA) as H2S synthesis inhibitor to examine the effects of H2S on plant growth, leaf reactive oxygen species, membrane lipid peroxidation, and antioxidants and key enzymes in the AsA-GSH cycle in "Dingyou 9" variety of naked oat under saline-alkali mixed stress. Results showed that spraying 50 μmol·L-1 NaHS could alleviate the inhibition of 50 mmol·L-1 saline-alkali mixed stress on the growth of naked oats, reduce the content of superoxide anions, H2O2, malondialdehyde, oxidized ascorbate (DHA), glutathione (GSH), and oxidized glutathione (GSSG) in leaves of naked oat under saline-alkali mixed stress, increase the ratio of AsA/DHA and GSH/GSSG, but did not affect the content of reduced ascorbic acid (AsA). Spraying NaHS significantly increased the activities of key enzymes, L-galactose dehydrogenase (GalDH) and L-galactono-1, 4-lactone dehydrogenase (GalLDH), for AsA synthesis pathways in naked oat leaves under salt-alkali mixed stress, as well as monodehydroascorbate reductase (MDHAR) in the AsA-GSH cycle, and decreased the activities of ascorbate peroxidase (APX) and dehydroascorbate reductase (DHAR), but did not affect the activities of ascorbate oxidase (AO) and glutathione reductase (GR). The addition of HA partially or completely relieved those aforementioned effects. Our results indicated that H2S could increase the efficiency of AsA-GSH cycle by promoting the synthesis of AsA and enhancing the activity of MDHAR, and reduce the oxidative damage of saline-alkali stress to naked oats.In order to clarify the mechanisms underlying dryland wheat quality improvement through sowing technology, the effects of wide space sowing (WSS), furrow sowing (FS), and drill sowing (DS) on soil moisture dynamics and grain protein formation in dryland wheat field were studied in Wenxi, Shanxi Province in 2017-2018 (normal year) and 2018-2019 (dry year). The results showed that compared with the DS, FS significantly increased soil water storage in the 0-200 cm depth at anthesis stage (8.2%-18.7%), and increased the soil water storage in 0-60 cm layer during the two years, 60-120 cm layer in normal year, and 120-200 cm layer in dry year. WSS significantly increased soil water storage in 0-200 cm layer at anthesis stage in normal year (5.2%). Compared with DS, FS significantly increased water consumption of anthesis to mature stage, while WSS significantly increased water consumption from sowing to anthesis stage in dry year. Compared with DS, the glutamine synthetase (GS) activity of grains at 15-35 days aftee, as well as soil water storage in 120-200 cm layer at anthesis stage in the dry year. In conclusion, FS was beneficial to increasing soil water storage at anthesis and water consumption after anthesis of dryland wheat, improving GS and GOGAT activities of flag leaf and grain, with positive consequences on yield and grain protein content. In addition, deep water storage was more conducive to quality improvement in the late growth period in the dry year.Unscientific fertilization, unstable grain quality, and low profit are the key problems on wheat production in slope cropland of Western Hubei. To solve these problems, three optimized planting patterns (high nitrogen and potassium reduction, HNPR; medium nitrogen and potassium reductionm, MNPR; low nitrogen and potassium reduction, LNPR) were conducted during two consecutive years to assess their effects on wheat yield, quality, profit, and fertilizer use efficiency in Danjiangkou Reservoir area, a typical slope cropland region with wheat-maize rotation. The results showed that the application of chemical fertilizer significantly increased grain yield (GY) and wet gluten content (WGC) of wheat. Compared with the conventional planting pattern (CK), the partial factor productivity (PFPK) and agricultural fertilizer use efficiency (AFUEK) of potassium were significantly improved in the three optimized planting patterns. The dry matter amount (DMA), GY, and crude protein content (CPC) were the highest under HNPR, which increased by 9.