全球不同气候带陆地植被净初级生产力变化趋势与可持续性

分析全球不同气候带陆地植被净初级生产力(NPP)的变化趋势与可持续性，对于估算全球陆地生态系统的结构、功能和碳源(汇)具有重要意义。运用Mann-Kendall突变检验、Theil-Sen斜率估计、Hurst指数分析全球不同气候带陆地NPP的变化趋势与可持续性。结果表明：(1)全球陆地NPP有明显的地域分异规律，呈现低纬高、高纬低，沿海高、内陆低的特点。约48.79%陆地生态系统的植被NPP得到了改善，其中显著改善的面积占全球陆地生态系统的8.45%,主要分布在北美洲北部和中部、亚马逊河流域西部、刚果盆地、欧洲南部、印度半岛西北部、中国黄土高原；轻微改善的面积占全球陆地生态系统的40.34%,主要分布在南美洲中南部、亚洲东部和澳大利亚大陆东部。(2)各气候带NPP变化趋势和突变点表现为：热带、亚热带、极地带的NPP呈不显著下降趋势(R²=0.111,P=0.176;R²=0.144,P=0.120;R²=0.002,P=0.854),热带无明显突变点，亚热带突变点为2015年，极地带突变点为2005年；干旱气候带的NPP...

Change trend and sustainability of vegetation net primary productivity of terrestrial ecosystems in different global climatic zones

Studying the change trend and sustainability of vegetation net primary productivity (NPP) of terrestrial ecosystems in different global climatic zones is important for estimating the structure, function and carbon sources (sinks) of global terrestrial ecosystems. In this article, the change trend and sustainability of NPP of terrestrial ecosystems in different global climatic zones were analyzed using Mann-Kendall mutation test, Theil-Sen slope estimation, and Hurst index. The results showed that: (1) The global terrestrial NPP had obviously regional differentiation. The NPP value was higher in the lower latitude regions than the higher latitude regions, and higher in coastal regions than hinterland. The area of NPP improved accounted for 48.79% of the global terrestrial ecosystem. Among these improved areas, the significantly improved area accounted for 8.45% of the global terrestrial ecosystem, which is mainly distributed in the north and central of North America, the west of the Amazon Basin, the Congo Basin, southern Europe, the northwest of the Indian Peninsula and the Loess Plateau of China; The slightly improved area accounted for 40.34% of the global terrestrial ecosystem, mainly distributed in central and southern South America, Eastern Asia and eastern Australia. (2) The change trend and mutation point of NPP in each climate zone were as follows: NPP in tropical, subtropical, and polar zones showed a non-significant decreasing trend (R²=0.111,P=0.176;R²=0.144,P=0.120;R²=0.002,P=0.854), with no significant mutation point in the tropics, the mutation point of the subtropics in 2015, and the mutation point of the polar zone in 2005; the NPP in arid showed a non-significant increasing trend (R²=0.036,P=0.450) with the mutation point in 2009; the NPP in temperate and cold temperate zone showed a significant increasing trend (R²=0.533,P=0.001) with the mutation point in 2014. (3) For the relationship between NPP with precipitation and temperature in each climate zone, NPP in arid climate zones and polar zones were moisture-limited, NPP in tropical and temperate cold climate zones were heat-limited, and NPP in subtropical zones was not significantly affected by temperature and precipitation. (4) In the coming period, the global terrestrial NPP shows a decreasing area (51.31%) more than increasing area (48.69%). The area of NPP is decreasing significantly more than the increasing in the arid climate zones, subtropical zones, and temperate cold temperate zones, which are the key focus areas for preventing NPP degradation in the future. These findings can provide references for domestic and international colleagues to compare and analyze the carbon source (sink) function of terrestrial ecosystems in different global climatic zones.