摘要
从植被类型、植被物候、气候因子时滞效应等方面研究2001年以来河北山区归一化植被指数(normalized difference vegetation index,NDVI)演变规律,并将气候因子时滞效应引入多元线性回归方法中,识别气候因子和人类活动对河北山区NDVI演变的贡献。结果表明:2001—2022年河北山区NDVI呈持续增长趋势,平均增速为0.0037/a,其中乔木林、灌木林和草地3种植被类型增速分别为0.0035/a、0.0040/a和0.0038/a;受气候变化影响,河北山区植被生长季变长,生长季开始时间平均提前9 d,而生长季结束时间仅提前1 d;降水对植被NDVI的影响主要发生在当月,而气温和潜在蒸散发对植被NDVI的影响存在1个月的滞后性,考虑气候因子的时滞效应后,气候变化和人类活动对河北山区NDVI演变的贡献分别为39%和61%,与不考虑气候因子时滞效应对比,多元线性回归的决定系数由0.80提高到0.87。人工水保措施是河北山区植被NDVI增长的主导因素,对快速改善山区生态环境至关重要,同时2001年以来降水、气温等气候因素也有利于植被恢复,对植被条件较好的区域,应以自然恢复为主,实现自然条件下的生态平衡。研究结果对优化山区水土保持工作方案,提高植被修复措施效果具有重要意义。
Since 2000,large-scale comprehensive control of soil and water loss has been carried out in the mountainous areas of Hebei Province.Through measures such as enclosure protection,afforestation and grass planting,and return of farmland to forest,the ecological environment in the mountainous areas has been significantly improved,especially the vegetation coverage in the mountainous areas has been significantly increased.However,the current research has not systematically analyzed the vegetation evolution law and causes in the mountainous areas of Hebei Province.It was difficult to scientifically evaluate the comprehensive control of soil and water loss in mountainous areas of Hebei Province.When analyzing the causes of vegetation evolution,the traditional multiple linear regression method usually adopts the climate variables and vegetation variables corresponding to each month,and fails to consider the"time-lag effect"of climate factors,which may lead to underestimating the contribution of climate factors.The evolution of NDVI in mountainous areas of Hebei Province was systematically studied from the aspects of vegetation types,vegetation phenology and time delay effect of climate factors.On this basis,a multiple linear regression model was established considering the time delay effect of climate,which is expected to answer the cause of NDVI evolution more accurately.With precipitation P,temperature T and potential evapotranspiration PET as independent variables and vegetation NDVI as dependent variables,a multiple linear regression model was constructed to improve the traditional residual analysis method,and the effects of climate change and human activities on vegetation NDVI changes were stripped away.The results showed that NDVI in mountainous areas of Hebei showed a continuous growth trend from 2001 to 2022,with an average growth rate of 0.0037/a.The growth rates of woodland,shrub and grassland were 0.0035/a,0.0040/a and 0.0038/a,respectively.Using the Mann-Kendall trend test method to analyze the significance
作者
田卫堂
刘淼
张子元
张学沛
王庆明
TIAN Weitang;LIU Miao;ZHANG Ziyuan;ZHANG Xuepei;WANG Qingming(Soil and Water Conservation Work Station of Hebei Province,Shijiazhuang 050011,China;Hebei Institute of Water Resources,Shijiazhuang 050057,China;China Institute of Water Resources and Hydropower Research,Beijing 100038,China)
出处
《南水北调与水利科技（中英文）》
CAS
CSCD
北大核心
2023年第5期962-971,共10页
South-to-North Water Transfers and Water Science & Technology
基金
国家重点研发计划项目(2021YFC3200204)
河北省水利科研项目(冀水科研2022-01
2023-72)。
关键词
河北山区
NDVI
滞后效应
变化归因
植被物候
mountainous area of Hebei
NDVI
hysteresis effect
change attribution
vegetation phenology
