生态环境学报2025，Vol.34Issue(4)：556-569,14.DOI:10.16258/j.cnki.1674-5906.2025.04.006
近40年红河流域(中国部分)水源涵养功能动态演变特征及驱动因素
Characteristics and Drivers of the Dynamic Evolution of Water Conservation Function in the Honghe River Basin(China Section)in the Last 40 Years
摘要
Abstract
Water conservation is a vital ecosystem service that plays a key role in regional ecological security and sustainable management of water resources.Understanding the spatial and temporal distributions,trends,and drivers of water conservation is of significant theoretical and practical importance for scientific planning and for advancing regional ecological protection and restoration.In this study,the InVEST model was employed to calculate the water conservation function of the Honghe River Basin(China section)over eight time intervals(every five years)from 1981 to 2020.Spatial and temporal variations,along with their internal differences,were analyzed using the Sen+Mann-Kendall test and natural discontinuity method.Subsequently,the GeoDetector model was applied to analyze the driving factors affecting the water conservation function,including precipitation,actual evapotranspiration,land use type,elevation,and slope.The findings of this study provide significant theoretical support for understanding the spatial and temporal heterogeneity of water conservation functions and their drivers in the Honghe River Basin(China).The results of the study indicate that:1)the average depth of water conservation in the study area is 68.7 mm,and the volume of water conservation is 5.77×109 m3.Over the past 40 years,the depth of water conservation has declined at an average rate of-0.097 mm·a-1,and the volume of water conservation has decreased at an average rate of-7.5×106 m3·a-1.From the second period onwards,the fluctuations in the water conservation function compared to the adjacent previous period were large,with specific fluctuation values of-11.0%,4.48%,11.1%,-7.74%,-6.54%,-5.76%,and 8.78%.The results of the Sen+Mann-Kendall analysis showed that the trend of change in water conservation function was primarily characterized by areas with little change,slight decreases,and slight increases,which collectively accounted for nearly 99.25%of the total area.By contrast,areas with significant increases and severe decreases were minimal,accounting for only 0.75%of the total study area.Woodlands,shrublands,and grasslands were the primary contributors to water conservation,accounting for 74.5,13.8,and 7.93%,respectively.Regression trend analysis revealed a decreasing trend in water conservation in woodland areas over the past 40 years,with a rate of change of-5.18×106 m3·a-1.The overall change in water conservation in wetlands,bare land,and waterbodies was minimal.Cultivated land and grassland exhibited a significant inverse change in water conservation capacity.Although the areas of cultivated land and grassland increased,water conservation decreased substantially,primarily because of increased land-use intensity,soil structure changes,and vegetation degradation.The primary conservation areas were concentrated within an elevation range of 400‒2400 m and on slopes ranging from 5° to 35°.The spatial distribution followed a pattern of high conservation in the southeast,and low conservation in the northwest.In addition,areas with high precipitation and relatively low evapotranspiration exhibited significantly higher water conservation capacities than the other areas.The need to reduce water conservation functional zones is reflected in various aspects,such as revealing spatial heterogeneity,supporting decision making on ecological protection,facilitating the optimal allocation of resources,supporting the ecological compensation mechanism,and addressing ecological and environmental challenges.This process not only helps to comprehensively understand the spatial pattern of regional ecosystem service functions,but also provides a scientific basis for watershed water resource management and ecological protection,and is an important means of achieving sustainable regional ecological development.In this study,the differences in the water-sourcing capacity of each functional area were primarily influenced by multiple factors such as topography,soil type,vegetation cover,and the intensity of human activities.2)The results of the analysis of functional areas delineated using the natural intermittent point method indicated that the area of the most important water conservation zone was the smallest,covering 8240.27 km2(10.8%of the total study area).However,its water conservation volume accounts for 20.2%of the total volume,with a water conservation rate as high as 1.53×105 m3·km-2.The area of the generally important water conservation zone is the largest,covering 46049.26 km2,which constitutes 60.3%of the total study area,but its water conservation volume is only 41.9%of the total,and the water conservation rate is only 9.91×104 m3·km-2.For areas with weak water conservation capacity,such as general functional zones,water conservation can be gradually improved through measures,such as returning farmland to forests,vegetation restoration,and scientific land-use planning.For areas with high water conservation capacity such as important functional zones,protective measures should be strengthened to enhance their water conservation capacity.Similarly,for areas with high conservation capacity,such as important functional zones,protection measures should be enhanced to minimize the potential impact of human interference on ecological functions and ensure the stability of their ecosystem service capacity.By implementing differentiated management,the coordinated development of water conservation functions on a regional scale can be promoted,thereby contributing to the sustainable enhancement of ecosystem services.3)In this study,a GeoDetector approach was employed to systematically analyze the drivers of changes in the water conservation function from 1981 to 2020 in the study area.This approach includes both single-factor and interaction analyses to explore the influence of each driver on the spatial heterogeneity of the water conservation function.In the single-factor analysis,the independent effects of key factors,such as climate,topography,and land use,on water conservation functions were quantified to reveal their contributions to the spatial distribution.In the interaction analysis,the effects of factor interactions were further analyzed to identify the combined influence of these drivers on the spatial heterogeneity of water conservation.The results of the GeoDetector analysis showed that among the single-factor drivers,precipitation was the primary driver of changes in the water conservation function in the study area,and it had significant explanatory power for spatial heterogeneity.Land use type and actual evapotranspiration had the second-largest effects on water conservation,whereas elevation and slope had weaker effects.The results of interaction detection revealed that each driving factor exhibited either a two-way enhancement or a non-linear enhancement in pairwise interactions.In other words,any single factor can significantly enhance the explanatory power of the spatial heterogeneity in water conservation when interacting with other factors.Specifically,the interactions between precipitation and land-use type,as well as between precipitation and actual evapotranspiration,significantly influenced the spatial heterogeneity of regional water conservation.These findings suggest that the synergistic effects of climatic factors and human activities dominate the spatial heterogeneity of the water conservation functions in the study area.These results provide a crucial basis for the further optimization of regional water management,planning,and ecological protection.Conclusion:An in-depth analysis of the main factors influencing water conservation is of great value in land use planning,strengthening water conservation measures,and promoting sustainable development in the region.The water conservation function of the Honghe River Basin(China section)exhibits significant temporal evolution characteristics and spatial distribution differences,with precipitation and land use playing key driving roles in the spatial and temporal heterogeneity.Our findings have important practical implications for regional water management and ecological protection.关键词
水源涵养/红河流域(中国部分)/InVEST模型/Sen+Mann-Kendall/地理探测器Key words
water conservation/Honghe River Basin(China section)/InVEST model/Sen+Mann-Kendall/GeoDetector分类
环境科学引用本文复制引用
张洪波,尹班,李春勇,崔松云,和艳,李小红,邓丽仙..近40年红河流域(中国部分)水源涵养功能动态演变特征及驱动因素[J].生态环境学报,2025,34(4):556-569,14.基金项目
水灾害防御全国重点实验室"一带一路"水与可持续发展科技基金项目(2022490411) （2022490411）
