库布其沙漠植被净初级生产力时空演变规律及其气象驱动因素分析

Analysis of Spatial-temporal Evolution and Meteorological Driving Factors of Vegetation Net Primary Productivity in Kubuqi Desert

摘要:

为探究库布其沙漠植被净初级生产力（Net primary production, NPP）的时空演变规律及其气象驱动因素，利用2001—2023年的MOD17A3HGF NPP数据，采用趋势分析、稳定性分析、相关分析、重要性分析等研究方法，分析库布其沙漠年均NPP的时空变化特征及其与潜在蒸散发、降水量、相对湿度、温度、水汽压亏缺量、风速等影响因素之间的关系。结果表明，2001—2023年库布其沙漠年均NPP为108.60 g/(m2·a)，范围为75.69～134.97 g/(m2·a)，整体呈现波动上升趋势。空间上，植被NPP主要分布在呼和木独镇西北部、吉日嘎朗图镇北部以及独贵塔拉镇东北部和南部。库布其沙漠地区植被NPP总体上为极显著增加趋势，稳定性波动较大，空间变异性显著。未来趋势分析表明，73.58%植被NPP具有反持续性，揭示了未来库布其沙漠植被NPP可能出现与当前变化趋势相反的情况。植被NPP与温度和降水量呈正相关的像元数占总像元数的比例最高，分别为90.56%和98.07%；植被NPP与风速和相对湿度呈负相关的比例最高，达60.57%和75.57%。潜在蒸散发和降水量为影响库布其沙漠植被NPP变化的主导因子。库布其沙漠植被NPP存在较强的时空异质性。本研究为荒漠生态系统的管理和可持续发展提供了科学依据。

Abstract:

To explore the spatio-temporal evolution patterns and meteorological driving factors of net primary productivity (NPP) in the Kubuqi Desert, MOD17A3HGF NPP data from 2001 to 2023 were used. Methods, including trend analysis, stability analysis, correlation analysis, and importance analysis were applied to examine the spatial and temporal variations in annual average NPP and its relationship with influencing factors such as potential evapotranspiration, precipitation, relative humidity, temperature, vapor pressure deficit, and wind speed. The results showed that the annual average NPP of the Kubuqi Desert from 2001 to 2023 was 108.60 g/(m2·a), ranging from 75.69 g/(m2·a) to 134.97 g/(m2·a), with an overall upward trend showing fluctuations. Spatially, vegetation NPP was primarily distributed in the northwestern part of Huhe Mud Town, the northern part of Jirigalangtu Town, and the northeastern and southern parts of Duguittara Town. The vegetation NPP of the Kubuqi Desert generally exhibited a highly significant increasing trend, with considerable stability fluctuations and significant spatial variability. Future trend analysis suggested that 73.58% of vegetation NPP may exhibit an anti-persistent trend, indicating potential future changes opposite to current trends. The positive correlation between vegetation NPP and temperature and precipitation accounted for 90.56% and 98.07% of total pixels, respectively. The NPP of vegetation had the highest negative correlation with wind speed and relative humidity, reaching 60.57% and 75.57%. Potential evapotranspiration and precipitation were identified as the main factors influencing changes in NPP in the Kubuqi Desert. The research result can provide a scientific basis for the management and sustainable development of desert ecosystems.