红沙泉露天煤矿碳储量时空动态变化分析
Spatiotemporal dynamic change analysis of carbon storage in desertification open⁃pit mine
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摘要: 明确矿区碳储量的演变规律及其对采矿活动的响应机制,是在碳达峰、碳中和“ 双碳” 目标 背景下推进矿区低碳减排和绿色高质量发展的重要手段。 以土地利用/覆被为基础,利用InVEST 模型评估新疆红沙泉矿区 2007—2020 年的碳储量变化,探究采矿扰动下土地利用变化对固碳功能 的影响,构建景观指数-采煤面积-碳储量耦合协调度模型探寻 3 者的发展协调程度,并利用景观 生态功能贡献率量化矿业景观的影响范围。 结果表明:1 2007—2020 年,红沙泉矿区未利用地以 1.95 km2 / a 的速度持续缩减,工矿用地和交通运输用地分别以 1.68,0.16 km2 / a 的速度持续扩张且 2 者的土地利用动态度最高(分别为 79.86%,46.25%),其余地类变化并不明显;2 2007—2020 年, 红沙泉矿区碳储量以 6 550.769 t / a 的速率呈持续下降的趋势,累计减少固碳 8.516×104 t,其减小区 域主要位于矿区北部,表现为北部未利用地(碳密度为 96.34 t/hm2)逐渐被不断扩张的工矿用 地(碳密度为53.48 t/hm2)斑块状分割侵占;草地和未利用地向工矿用地转移是造成碳储量下降的 主要原因;3 景观尺度上,红沙泉矿区景观破碎化加重(斑块数目 NP、斑块密度 PD、形状指数 LSI 的增幅分别为 194,1.185,6.856,聚合度 AI 的降幅为 0.104),生物多样性 SHDI 和均匀度 SHEI 上 升(增幅为 0.445,0.236);斑块尺度上,工矿用地和交通运输用地的景观向聚集化有序性发展,而草 地和未利用地向破碎化无序型发展;景观指数、采煤面积与碳储量的耦合协调度呈不断减小趋势, 由 2007 年的 0.948(优质协调)下降为 2020 年的 0.602(初级协调);4 距离红沙泉矿区矿业景观 15 km 内,距离越远,平均单位面积碳储量越高;矿区碳储量敏感区可分为 3 级:极敏感区(0 ~ 7 km)、敏感区(7~15 km)、不敏感区(15 km 以外)。 该研究能够定量反映矿区固碳功能及其与景 观格局、采煤面积的耦合机制,以及矿业景观的影响范围,可为矿区实施低碳高质量发展提供思路, 促进矿区精准服务于碳达峰、碳中和“ 双碳” 目标。Abstract: To clarify the evolution law of carbon storage in mining area and its response mechanism to mining activities is an important means to promote low⁃carbon emission reduction and green high⁃quality development of mining area under the background of carbon peak and carbon neutral “double carbon” goal. Based on land use/ cover,the In⁃ VEST model was used to evaluate the change of carbon storage in the Hongshaquan Mining area of Xinjiang from 2007 to 2020,explore the impact of land use change on carbon sequestration function under mining disturbance,and establish the coupling coordination degree model of landscape index,coal mining acreage and carbon storage for explo⁃ ring the development coordination degree of three parameters above. The influence range of mining landscape is quan⁃ tified using the contribution rate of landscape ecological function. The results show that:1 From 2007 to 2020,the un⁃ used land in the Hongshaquan mining area continued to shrink at a rate of 1.95 km2 / a,and the industrial and mining land and transportation land continued to expand at a rate of 1.68 km2 / a and 0.16 km2 / a,respectively. The dynam⁃ ic degree of land use is the highest (79.86% and 46.25% respectively),and the other land types have not changed significantly. 2 From 2007 to 2020,the carbon storage of the Hongshaquan Mining area showed a trend of continu⁃ ous decline at the rate of 6 550. 769 t / a, and the cumulative reduction of carbon sequestration was 8. 516 × 104 t. The change of carbon storage space was mainly weakened in the north,showing that the unused land with carbon den⁃ sity of 96.34 t / hm2 in the north was gradually invaded by the expanding industrial and mining land with carbon density of 53.48 t / hm2 . The main reason for the decline of carbon storage was the transfer of grassland and unused land to in⁃ dustrial and mining land. 3 On the landscape scale,the landscape fragmentation of the Hongshaquan mining area in⁃ creased (patch number NP,patch density PD and shape index LSI increased by 194,1.185 and 6.856,respectively, while the convergence AI decreased by 0.104),and biodiversity SHDI and uniformity SHEI increased (0.445 and 0.236). On the patch scale,the landscape of industrial and mining land and transportation land tended to be clustered and orderly,while grassland and unused land tended to be fragmented and disordered. The coupling coordination de⁃ gree of landscape index,coal mining area and carbon storage is in a weakening trend as a whole,from 0.948 (high⁃ quality coordination) in 2007 to 0.602 (primary coordination) in 2020. 4 Within 15 km from the mining landscape of the Hongshaquan Mining area,the farther the distance,the higher the average carbon storage per unit area. The car⁃ bon storage sensitive area in the mining area can be divided into three levels:extremely sensitive area (0-7 km),sen⁃ sitive area (7-15 km) and insensitive area (beyond 15 km). This study can quantitatively reflect the carbon seques⁃ tration function of the mining area and its coupling mechanism with landscape pattern and coal mining area,as well as the influence range of mining landscape. Also,it can provide ideas for the implementation of low⁃carbon and high⁃ quality development of the mining area,and promote the precise service of the mining area to achieve carbon peak and carbon neutral “dual carbon”goals.