Donnellylamb6394

Among all the treatments, the highest values of ANTH-RB and NBI-G, soluble sugar content, and activities of CAT, SPS, SS, and INV presented in NaCl-M2 treatment, the highest values of SPAD, FLAV, and FERARI presented in NaCl-M3 treatment, the highest activity of superoxide dismutase (SOD) presented in NaCl-M1 treatment, the highest activity of glutathione peroxidase (GSH-Px) presented in NaCl treatment, and the highest peroxisome (POD) activity presented in CK. The 14 significant physiological and biochemical indicators in the leaves of L. barbarum seedling were analyzed by grey system correlation degree method. Our results suggested that the weighted correlation degree of phy-siological and biochemical indices of L. barbarum inoculated potassium-solubilizing bacteria was higher than that under CK and NaCl treatments. The highest weighted correlation was observed in NaCl-M2 treatment. Therefore, adding KSBGY02 potassium-solubilizing bacteria could alleviate the salt stress for L. barbarum seedlings.Analyzing the effects of nutrient addition on the functional traits of desert plants is important for revealing the responses of desert plant species to environmental changes. In this study, we examined the responses of whole plant, root, stem, leaf and fruit traits of Lycium ruthenicum to the addition of N and P, with an experiment with three (low, medium and high) N and P addition levels and three N/P ratios (51, 151 and 451). The results showed that functional traits of L. read more ruthenicum had divergent responses to NP addition level and N/P ratio. With the increases of NP addition level, the biomass and specific leaf area were increased, while the root-shoot ratio, leaf dry matter content, root tissue density and specific root length were decreased. Belowground biomass, specific root length and net photosynthetic rate increased with the increases of N/P ratio. The coefficient of variation of 17 functional traits was 7.3%-69.1%. The biomass, root-shoot ratio and speci-fic root length were sensitive traits to NP of L. ruthenicum. L. ruthenicum adapted to the fluctuations of soil nutrient environment through changing resource utilization strategy, altering root carbon allocation, and also the trade-off and covariance among traits and inconsistent response.The valleyes of Hengduan Mountains contain the landscapes with high heterogeneity as well as high diversity of climate and vegetation types. To explore the soil cycling of four elements (C, N, P, S) across the parallel valleys of Nujiang River, Lancang River, Jinsha River and Yuanjiang River in western Yunnan, we collected top soils (0-10 cm) in forests, grasslands, and croplands. The activities of soil enzymes, including β-glucosidase (BG), β-N-acetylglucosaminidase (NAG), acid phosphatase (AP), and sulfatase (SU), which drive the soil C, N, P and S cycling, were determined. We analyzed the relationships of soil enzymatic activities and their stoichiometric characteristics with environmental factors. The activities of both AP and NAG had significant difference among different basins and different land types. The activities of AP, BG, NAG and SU were significantly positively related with each other. From southeast to northwest, the activities of BG, NAG, and SU increased with the altitude. Across all basins, the ecoenzymatic ratios of soils always ranked as APSU > BGSU > NAGSU > BGNAG > BGAP > NAGAP. Compared with forest and grassland soil, cropland soils in each watershed had a higher BGNAG and a lower NAGAP (except Yuanjiang River basin). Moreover, APSU, BGSU and NAGSU of cropland soils were lower than those of forest and grassland in Yuanjiang River basin. However, they were higher than forest and lower than grassland in both Lancang River basin and Jinsha River basin. Soil enzyme activities and enzymatic stoichiometry were affected by physicochemical properties of soil, climate, and location, with the most contribution from soil physicochemical properties. Agricultural land use significantly affected the stoichiometry of CNP acquiring enzymes in soils by reducing the activity of N-degrading enzymes relative, resulting in the increases of BGNAG and the decreases of NAGAP. Agricultural activities had limited effects on other enzymatic stoichiometries.We measured the total vegetation carbon stock in the widely distributed natural grassland of meadow steppe (MS), warm steppe (WS), steppe desert (SD) and desert steppe (DS)] in Ningxia, using survey and sampling method. The results showed that the average carbon rate of vege-tation, shrubs and root were 0.40, and that of litter was 0.39. The total vegetation carbon density of meadow steppe, warm steppe, steppe desert and desert steppe (including aboveground vegetation, litter and roots) was 470.26, 192.23, 117.17 and 83.36 g·m-2, while that of aboveground vegetation was 87.35, 68.50, 59.32 and 40.05 g·m-2, and that of roots was 344.29, 108.83, 50.65 and 30.29 g·m-2, litter carbon storage was 38.62,14.91, 7.19 and 13.03 g·m-2, respectively. The order of those grassland types ranked as MS＞WS＞SD＞DS. Root carbon storage contributed the most to carbon storage in meadow steppe and warm steppe, and aboveground vegetation carbon storage contributed the most to steppe desert and desert steppe. Root carbon storage showed a decreasing trend with the increases of soil depth within 40 cm soil layer. For the spatial distribution of total carbon stock, the southern part of meadow steppe and temperate steppe had obviously higher carbon stock than the middle and north part of desert steppe and steppe desert.Moisture is an important factor affecting the priming effect of soil organic carbon (SOC). However, empirical evidence for its effect in mountain meadows soil is lacking. We conducted a 126-day laboratory incubation experiment with the high altitude (2130 m) mountain meadow soil in Wuyi Mountain, by adding 13C-labelled glucose combined with controlling soil moisture (30% and 60% of field water capacity, FWC). The CO2 concentration and 13C-CO2 abundance were measured regularly to examine the differences of SOC mineralization and priming effects under different water conditions and the driving factors. Our results showed that SOC mineralization rate increased with increasing soil water content. The priming effect of meadow soil with different soil moisture showed a decreasing trend with the increases of incubation time. The priming effect in soils with low FWC soil was significantly greater than that with high FWC. At the end of incubation, the cumulative priming effect of low FWC soil was 61.4% higher than that of high FWC soil.