气候变化和人类活动对陕西省植被NPP影响的定量分析

Quantitative Analysis of the Impact of Climate Change and Human Activities on Vegetation NPP in Shaanxi Province

定量评估气候变化和人类活动对陆地生态系统碳循环的影响,对于深入理解植被变化驱动机制和生态建设与保护具有重要意义。基于2000—2019年生态过程模型BIOME-BGC计算的实际净初级生产力和气候模型计算的潜在净初级生产力,定量分析气候变化和人类活动对陕西植被生态系统的影响。结果表明,2000—2019年间,陕西省植被NPP的变化主要由气候驱动的区域占总面积的11.96%;叠加上人类活动影响,且后者作用更强的区域占比为86.93%。陕西省的植被NPP增加的区域占总面积的98.06%,其中有11.93%的区域是由气候因素驱动,主要分布在关中地区和汉中盆地的农作区;86.13%是由人类活动驱动,主要分布在陕北、陕南地区,说明了这两个地区退耕还林、天然林保护等生态建设工程取得了显著成效。减少的区域占总面积的0.83%,其中有0.03%的区域是由气候因素驱动,零星分布在全省各地;而0.8%的区域是由人类活动,尤其是城镇建设所致,分布在城镇周边区域。还有1.11%的面积NPP没有发生变化。陕西省植被NPP的变化受到气候和人类活动两种驱动力的作用,而主要驱动力是人类活动。

Quantitative assessment of the impact of climate change and human activities on terrestrial ecosystem carbon cycle is of great significance for understanding of vegetation change driving mechanism, ecological construction and protection. Based on the actual net primary productivity(NPP) calculated by the model Biome-BGC from 2000 to 2019 and the potential net primary productivity calculated by the climate model, this paper quantitatively analyzed the impact of climate change and human activities on vegetation ecosystem in Shaanxi Province. The results showed that the change of vegetation NPP in Shaanxi Province was mainly driven by climate, accounting for 11.96% of the total area. Climate superimposed with the influence of human activities which played a more important role, accounting for 86.93% of the total area. The increase of vegetation NPP in Shaanxi Province accounted for 98.06% of the total area. Among this, 11.93% of the total area was driven by climate factors, which mainly distributed in the agricultural areas of Guanzhong area and Hanzhong Basin. 86.13% of the total area was driven by human activities, which mainly distributed in northern and southern Shaanxi. These results indicated that the ecological construction projects such as returning farmland to forest and natural forest protection have made remarkable achievements in the two regions. The reduced area accounts for 0.83% of the total area. Among this, 0.03% of the total area was driven by climate factors and distributed throughout the province, while 0.8% of the total area caused by human activities distributed in the surrounding areas of cities and towns and was mainly attributed to urban construction.There was no change in NPP in 1.11% of the total area. In conclusion, the changes of vegetation NPP in Shaanxi Province were mainly affected by climate and human activities, with the latter being the main driving force.