[Objectives] To study structural characteristics of Lycium ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River, and provide theoretical basis for ecolo...[Objectives] To study structural characteristics of Lycium ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River, and provide theoretical basis for ecological protection and management in the lower reaches of Shiyang River. [Methods] One-way ANOVA analysis and correlation analysis were carried out with the aid of SPSS19.0 software for different types of desert rangeland soils. [Results](i) Among the communities surveyed, there are 31 species belonging to 9 families and 28 genera, including 12 shrub plants, 8 perennial herbs and 11 annual herbs. There are more single genus, occupying 50% of total genus. L. ruthenicum occupies an important position in the community with relatively higher importance value. It plays a dominated role in the community.(ii) In the soils with depths of 0-10 cm, 10-20 cm, 20-40 cm and 40-60 cm in different types of desert rangeland, the organic carbon contents in the saline alkali soil were the highest, with the values of 1.08%, 0.98%, 0.89% and 0.972%, respectively. Compared with that in sandy land, soil organic carbon in saline alkali land(0-10 cm) had the significant difference(P<0.05), available soil potassium in saline alkali land(except the depth of 20-40 cm) and the total phosphorus content in saline alkali land(0-10 cm) had the significant difference(P<0.05), the total soil nitrogen, alkali-hydrolyzable nitrogen, available phosphorus and the total potassium content had no significant difference(P>0.05). Soil organic carbon, available soil phosphorus in saline alkali land, total soil potassium on sand dune and total soil phosphorus in saline alkali land and gravel in different soil layers of the same type of desert rangeland had distinct aggregation effect.(iii) The soil microbial biomass in different types of desert rangeland displayed from high to low as saline alkali land > sandy land > fixed and semi fixed sandy land > gravel. The discrepancy of soil microbial biomass varied in different types of desert rangeland. The four soil enzyme activities in salinization was the highest. Soil invertase activity in saline alkali land in different soil layers were the highest. For different soil layers in the same type of desert rangeland, soil microbial biomass and invertase decreased gradually with the deepening of soil layer.(iv) There was a significant positive correlation between soil organic matter and microbial biomass carbon, microbial biomass nitrogen, phosphatase and sucrase(P<0.01), and a significant positive correlation with urease and catalase(P<0.05). Phosphorus content was significant positively correlated with urease, phosphatase and invertase(P<0.01), and positively correlated with microbial biomass carbon(P<0.05). Soil available potassium content was significant positively correlated with microbial and phosphatase(P<0.01). [Conclusions] The species of L. ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River clearly shows that most species belong to a few families, and a few species belong to most families, and many species are single genus or single family. Soil organic carbon, soil available phosphorus, total phosphorus, soil microbial biomass and enzyme activity in salinization land had distinct surface aggregation effects, so salinization land provides excellent growth environment for the growth of L. ruthenicum, which is of great significance for the protection of L. ruthenicum population.展开更多
Soil organic carbon(SOC)is a critical variable used to determine the carbon balance.However,large uncertainties arise when predicting the SOC stock in soil profiles in Chinese grasslands,especially on desert rangeland...Soil organic carbon(SOC)is a critical variable used to determine the carbon balance.However,large uncertainties arise when predicting the SOC stock in soil profiles in Chinese grasslands,especially on desert rangelands.Recent studies have shown that desert ecosystems may be potential carbon sinks under global climate change.Because of the high spatial heterogeneity,time-consuming sampling methods,and difficult acquisition process,the relationships the SOC storage and distribution have with driving factors in desert rangelands remain poorly understood.Here,we investigated and developed an SOC database from 3162 soil samples(collected at depths of 0−10 cm and 10−20 cm)across 527 sites,as well as the climate conditions,vegetation types,and edaphic factors associated with the sampling sites in the desert rangelands of northern Xinjiang,north-west China.This study aims to determine the SOC magnitude and drivers in desert rangelands.Our findings demonstrate that the SOC and SOC density(SOCD)were 0.05−37.13 g·kg^(-1)and 19.23−9740.62 g·m^(-2),respectively,with average values of 6.81±5.31 g·kg^(-1)and 1670.38±1202.52 g·m^(-2),respectively.The spatial distributions of SOC and SOCD all showed gradually decreasing trends from south-west to north-east.High-SOC areas were mainly distributed in the piedmont lowlands of the Ili valley,while low-SOC regions were mainly concentrated in the north-west area of Altay.The redundancy analysis results revealed that all environmental factors accounted for approximately 37.6%of the spatial variability in SOC;climate factors,vegetation factors,and soil properties explained 15.0%,1.7%,and 12.3%,respectively.The structural equation model(SEM)further indicated that evapotranspiration,average annual precipitation,and the SWC were the dominant factors affecting SOC accumulation,mainly through direct effects,although indirect effects were also delivered by the vegetation factors.Taken together,the results obtained herein updated the SOC data pool available for desert rangelands and clarified the main driving factors of SOC variations.This study provided supporting data for the sustainable use and management of desert rangelands and the global ecosystem carbon budget.展开更多
基金Supported by Regional Fund Project of Gansu Province,China(31560128,31760709,31860175,31460134,31460223)Open Fund Project of Key Laboratory of Gansu Province(GSDC201506)Youth Science and Technology Project of Gansu Province(18JR3RA019)
文摘[Objectives] To study structural characteristics of Lycium ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River, and provide theoretical basis for ecological protection and management in the lower reaches of Shiyang River. [Methods] One-way ANOVA analysis and correlation analysis were carried out with the aid of SPSS19.0 software for different types of desert rangeland soils. [Results](i) Among the communities surveyed, there are 31 species belonging to 9 families and 28 genera, including 12 shrub plants, 8 perennial herbs and 11 annual herbs. There are more single genus, occupying 50% of total genus. L. ruthenicum occupies an important position in the community with relatively higher importance value. It plays a dominated role in the community.(ii) In the soils with depths of 0-10 cm, 10-20 cm, 20-40 cm and 40-60 cm in different types of desert rangeland, the organic carbon contents in the saline alkali soil were the highest, with the values of 1.08%, 0.98%, 0.89% and 0.972%, respectively. Compared with that in sandy land, soil organic carbon in saline alkali land(0-10 cm) had the significant difference(P<0.05), available soil potassium in saline alkali land(except the depth of 20-40 cm) and the total phosphorus content in saline alkali land(0-10 cm) had the significant difference(P<0.05), the total soil nitrogen, alkali-hydrolyzable nitrogen, available phosphorus and the total potassium content had no significant difference(P>0.05). Soil organic carbon, available soil phosphorus in saline alkali land, total soil potassium on sand dune and total soil phosphorus in saline alkali land and gravel in different soil layers of the same type of desert rangeland had distinct aggregation effect.(iii) The soil microbial biomass in different types of desert rangeland displayed from high to low as saline alkali land > sandy land > fixed and semi fixed sandy land > gravel. The discrepancy of soil microbial biomass varied in different types of desert rangeland. The four soil enzyme activities in salinization was the highest. Soil invertase activity in saline alkali land in different soil layers were the highest. For different soil layers in the same type of desert rangeland, soil microbial biomass and invertase decreased gradually with the deepening of soil layer.(iv) There was a significant positive correlation between soil organic matter and microbial biomass carbon, microbial biomass nitrogen, phosphatase and sucrase(P<0.01), and a significant positive correlation with urease and catalase(P<0.05). Phosphorus content was significant positively correlated with urease, phosphatase and invertase(P<0.01), and positively correlated with microbial biomass carbon(P<0.05). Soil available potassium content was significant positively correlated with microbial and phosphatase(P<0.01). [Conclusions] The species of L. ruthenicum community and soil properties on different types of desert rangeland in the lower reaches of Shiyang River clearly shows that most species belong to a few families, and a few species belong to most families, and many species are single genus or single family. Soil organic carbon, soil available phosphorus, total phosphorus, soil microbial biomass and enzyme activity in salinization land had distinct surface aggregation effects, so salinization land provides excellent growth environment for the growth of L. ruthenicum, which is of great significance for the protection of L. ruthenicum population.
基金funded by the Open Project of Key Laboratory of Xinjiang Uygur Autonomous Region(No.2022D04003)the National Basic resource survey of China(No.2017FY100200)+1 种基金the National Natural Science Foundation of China(Grant No.32060408)the graduate scientific research and innovation project of Xinjiang Agricultural University(No.XJAUGRI2021003).
文摘Soil organic carbon(SOC)is a critical variable used to determine the carbon balance.However,large uncertainties arise when predicting the SOC stock in soil profiles in Chinese grasslands,especially on desert rangelands.Recent studies have shown that desert ecosystems may be potential carbon sinks under global climate change.Because of the high spatial heterogeneity,time-consuming sampling methods,and difficult acquisition process,the relationships the SOC storage and distribution have with driving factors in desert rangelands remain poorly understood.Here,we investigated and developed an SOC database from 3162 soil samples(collected at depths of 0−10 cm and 10−20 cm)across 527 sites,as well as the climate conditions,vegetation types,and edaphic factors associated with the sampling sites in the desert rangelands of northern Xinjiang,north-west China.This study aims to determine the SOC magnitude and drivers in desert rangelands.Our findings demonstrate that the SOC and SOC density(SOCD)were 0.05−37.13 g·kg^(-1)and 19.23−9740.62 g·m^(-2),respectively,with average values of 6.81±5.31 g·kg^(-1)and 1670.38±1202.52 g·m^(-2),respectively.The spatial distributions of SOC and SOCD all showed gradually decreasing trends from south-west to north-east.High-SOC areas were mainly distributed in the piedmont lowlands of the Ili valley,while low-SOC regions were mainly concentrated in the north-west area of Altay.The redundancy analysis results revealed that all environmental factors accounted for approximately 37.6%of the spatial variability in SOC;climate factors,vegetation factors,and soil properties explained 15.0%,1.7%,and 12.3%,respectively.The structural equation model(SEM)further indicated that evapotranspiration,average annual precipitation,and the SWC were the dominant factors affecting SOC accumulation,mainly through direct effects,although indirect effects were also delivered by the vegetation factors.Taken together,the results obtained herein updated the SOC data pool available for desert rangelands and clarified the main driving factors of SOC variations.This study provided supporting data for the sustainable use and management of desert rangelands and the global ecosystem carbon budget.