| Arid zone wetlands play an important role in maintaining the stability of the arid zone ecosystem,regulating soil degradation and purifying the environment,regulating climate,and storing water.As the center of the combined evolution of desertification and oasis on the northern slope of Tianshan Mountain,the Ebinur Lake Wetland has continued to increase in human activities,the lake surface has gradually decreased,the groundwater level has decreased year by year,the soil salinity has increased,the saline-alkali desert has deteriorated,and the ecosystem has become more and more fragile.Due to the high salt content of the soil,desert halophytes such as Haloxylon ammodendron and Tamarix are widely distributed here.Desert halophytes not only reflect the differences in regional ecological environment,but also affect their soil properties,which play a role in maintaining the balance of regional ecosystems.positive effect.This paper selects the typical dominant species of Haloxylon ammodendron in the Ebinur Lake wetland,studies the soil water-fertilizer characteristics under its cover,and finds the spatiotemporal evolution trend,which is the protection and reconstruction of forest and vegetation restoration in arid desert areas,and grasps the space of soil water-fertilizer content in arid area wetlands.The law of distribution is of great significance.In order to explore the characteristics of soil waterfertilizer content and influencing factors under the cover of Haloxylon ammodendron in the Ebinur Lake wetland,the soil samples under 38 representative Haloxylon ammodendron vegetations in the study area,a total of 114 soil samples of organic matter,The salt and water content are measured,the factors affecting the content and distribution are discussed,and the changes in organic matter and salt content over time are compared with the previous research data and the reasons for the changes.The main research results are as follows:(1)Analysis of statistical characteristics of soil water-fertilizer content in the study area: The degree of variability of organic matter,salinity,and moisture in the 0-60 cm soil layer in study areas A,B,and C are all in line with medium variation(10%<CV<100%),and varies with the soil As the depth of the layer increases,the content gradually decreases,and the difference between the maximum and minimum content gradually increases,the amplitude is small and the change trend is consistent,and the content is generally low.According to the relevant standards of the second national soil survey,organic matter is at the "slightly lacking" level of grades 5 and 6.According to the latest relevant standards of "Xinjiang soil",it can be known that all soils are non-salinized soils(<3G/kg).(2)Analysis of the spatial differentiation characteristics of soil water-fertilizer content in the study area: Soil organic matter and salinity in area A have a medium spatial correlation(0.25-0.75)in the 0-20 cm and 40-60 cm soil layers,while the 20-40 cm soil layer is relatively weak.Correlation(>0.75),the spatial correlation of moisture in each soil layer of 0-60 cm is weak(>0.75).The organic matter in the 0-20 cm and 20-40 cm soil layers in Zone B shows a weak spatial correlation(>0.75),the salinity shows a medium degree of spatial autocorrelation(0.25-0.75),and the organic matter in the 40-60 cm soil layer shows a medium degree of spatial correlation(0.25-0.75),the spatial correlation of salinity is weak(>0.75),the spatial correlation of moisture in 0-20 cm is weak(>0.75),and the soil layer of 20-40 cm and 40-60 cm has a moderate spatial correlation(0.25-0.75).The organic matter in the surface layer of the C area shows a weak spatial correlation(>0.75),and the salinity correlation is medium(0.25-0.75),and the organic matter in the 20-40 cm and 40-60 cm soil layers has a medium spatial correlation(0.25-0.75).The correlation is weak(>0.75),the moisture in the surface layer,40-60 cm shows a weak spatial correlation(>0.75),and the 20-40 cm soil layer shows a medium spatial correlation(0.25-0.75).It can be seen from the spatial distribution that the distribution pattern of organic matter in 0-20 cm and 40-60 cm soil shows a decreasing trend from the middle to both sides,and the change trend of the 20-40 cm soil layer shows a decreasing trend from northwest to southeast.The distribution pattern of the salt content in each soil layer is basically the same,and the whole is increasing from west to east.The overall water content showed a trend of decreasing from the middle of Lake Aibi to both sides,and gradually decreasing from the northwest to the southeast.(3)Comparative analysis of the temporal and spatial changes of soil waterfertilizer content in the study area: Through the statistical analysis of organic matter and salinity,it can be seen that the variation of organic matter and salinity in 2012 and2019 are in line with medium variation(10%<CV<100%).The change trend of content in 2012 and 2019 is the same,and the content gradually decreases with the increase of soil depth.In 2012,the average organic matter content was at the "slightly lacking" level of grades 3 and 4,and in 2019 it was at the "slightly lacking" level of grades 5and 6.In 2012 and 2019,the salinization degree of each soil layer was at a mild level.It can be seen from the spatial distribution map that the organic matter content in each soil layer has a consistent change trend in 2012.The organic matter content in the eastern part of Lake Aibi is higher,and the western content is generally lower.The overall content change gradually increases from west to east.In 2019,the surface layer,40% The change trend of organic matter in the-60 cm soil layer showed a gradual decrease from the middle of Lake Aibi to both sides.The 20-40 cm soil layer decreases from northwest to southeast.In 2012,the low-salt content in the 0-60 cm soil layer was distributed in the south and north of Lake Aibi,and the overall content change trend showed an increase from the middle of Lake Aibi to both sides.In 2019,the high-value area of salt in the 0-60 cm soil layer is in the east,and the low-value area is in the west,and the overall content is gradually increasing from west to east.From 2012 to 2019,the soil organic matter in the Ebinur Lake Wetland Research Area showed a decreasing trend,and the salt content showed an increasing trend.According to meteorological data,in the past eight years,the annual average temperature,sunshine hours,and wind direction in the Ebinur Lake area have shown a downward trend,while the relative humidity,precipitation,and wind speed have shown an upward trend. |
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