气候变化下黑土区陆地生态系统碳储量时空格局与模拟

Spatio-temporal Pattern and Simulation of Terrestrial Ecosystem Carbon Storage in Black Soil Region under Climate Change

以典型黑土区——三江平原为研究区,采用最小二乘法揭示1990-2020年气候变化下研究区陆地生态系统碳储量变化趋势,借助重心分析和冷热点分析方法揭示研究区陆地生态系统碳储量时空分异特征,利用地理加权回归法分析气候因子对碳储量的影响,并借助CMIP6数据模拟和预测高强迫情景(SSP585)和中等强迫情景(SSP245)下陆地生态系统碳储量。结果表明:气候变化背景下1990-2020年研究区碳储量呈波动下降趋势,碳储量损失约2.66×10^(7)t;碳储量高值区主要分布在西北部和东部地区,碳储量低值区主要分布在北部和东南部地区;1990-2020年研究区碳储量下降速率变化幅度较大,其中鹤岗市碳储量下降速率最大,佳木斯市最小。1990-2020年研究区碳储量重心向东北方向移动1340m,其中2000-2020年向东北方向偏移1680m;碳储量热点区呈片状和块状分布格局,冷点区呈片状和带状分布格局,热点区范围基本保持不变,冷点区范围缩小。1990-2020年研究区年均气温、年降水量与碳储量关系具有显著性,呈正负无规律交错分布的空间格局。气候与土地利用变化决定碳储量的时空格局,其中林地-林地和耕地-耕地碳储量损失最大。在SSP585和SSP245情景下,2030年研究区碳储量分别为2.22×10^(7)t和2.26×10^(7)t,相比2020年分别减少2.17×10^(7)t和2.13×10^(7)t,碳储量空间分布格局未发生显著改变,但冷热点区范围均缩小,重心将持续向东北方向偏移6525m和6000m。

Taking Sanjiang Plain,a typical black soil region,as the study area,and the least squares method was used to reveal the change trend of terrestrial ecosystem carbon stocks under climate change in 1990-2020.By means of barycentric analysis and cold hot spot analysis,the spatial and temporal differentiation of terrestrial ecosystem carbon stocks in study area was revealed,and the influence of climate factors on carbon stocks was analyzed by geographical weighted regression method.CMIP6 data were used to simulate and predict terrestrial ecosystem carbon stocks under SSP585 and SSP245.The results showed as follows:under the background of climate change,carbon storage in study area showed a fluctuating trend of decline in 1990-2020,and carbon storage loss was about 2.66×10^(7)t.The regions with high carbon storage value were mainly distributed in the northwest and east,while the regions with low carbon storage value were mainly distributed in the north and southeast.The rate of carbon storage decline in the study area was changed greatly in 1990-2020,and the rate of carbon storage decline in Hegang City was the largest,while the rate of carbon storage decline in Jiamusi City was the minimum.The center of gravity of carbon storage in study area was shifted 1340m to the northeast in 1990-2020,and 1680m to the northeast in 2000-2020.The distribution pattern of carbon storage hotspots was sheet-like and blocky,and the distribution pattern of cold spots was sheet-like and banded,the range of hot spots was basically unchanged,and the range of cold spots was reduced.The relationship between annual temperature,annual precipitation and carbon storage in study area was significant in 1990-2020,showing a positive and negative interleaving spatial pattern.Climate and land use change determined the spatio-temporal pattern of carbon storage,and forest-forest land and cultivated land-cultivated land led to the greatest loss of carbon storage.Under the SSP585 and SSP245 scenarios,the carbon reserves in study area in 2030 were 2.22×10^(7)t and 2.26×10^(7)t,respectively,which were reduced by 2.17×10^(7)t and 2.13×10^(7)t compared with that in 2020,respectively.The spatial distribution pattern of carbon reserves was not changed significantly,but the areas of cold hot spots were reduced.The center of gravity would continue to shift 6525m and 6000m to the northeast.