水保所知识产出(1956---)知识库

Vegetation changes in the Upper White Nile River (UWNR) are of great significance to
the maintenance of local livelihoods, the survival of wildlife, and the protection of species habitats.
Based on the GIMMS NDVI3g and MODIS normalized difference vegetation index (NDVI) data,
the temporal and spatial characteristics of vegetation changes in the UWNR from 1982 to 2020
were analyzed by a Theil-Sen median trend analysis and Mann-Kendall test. The future trend of
vegetation was analyzed by the Hurst exponential method. A partial correlation analysis was used
to analyze the relationship of the vegetation and climate factors, and a residual trend analysis was
used to quantify the influence of climate change and human activities on vegetation change. The
results indicated that the average NDVI value (0.75) of the UWNR from 1982 to 2020 was relatively
high. The average coefficient of variation for the NDVI was 0.059, and the vegetation change was
relatively stable. The vegetation in the UWNR increased 0.013/10 year on average, but the vegetation
degradation in some areas was serious and mainly classified as agricultural land. The results of a
future trend analysis showed that the vegetation in the UWNR is mainly negatively sustainable, and
62.54% of the vegetation will degrade in the future. The NDVI of the UWNR was more affected by
temperature than by precipitation, especially on agricultural land and forestland, which were more
negatively affected by warming. Climate change and human activities have an impact on vegetation
changes, but the spatial distributions of the effects differ. The relative impact of human activities
on vegetation change accounted for 64.5%, which was higher than that of climate change (35.5%).
Human activities, such as the large proportion of agriculture, rapid population growth and the rapid
development of urbanization were the main driving forces. Establishing a cross-border drought
joint early warning mechanism, strengthening basic agricultural research, and changing traditional
agricultural farming patterns may be effective measures to address food security and climate change
and improve vegetation in the UWNR.