不同土地利用情景下汾河上游地区碳储量评估

陆地生态系统碳储量对预测气候变化、温室气体排放和减少等具有重要意义,而土地利用格局变化是研究陆地生态系统碳储量的基础,它直接影响陆地生态系统结构及分布情况,进而改变陆地生态系统碳储量。运用SDCLUE-S复合模型模拟了未来不同情景下汾河上游土地利用情况,并采用InVEST模型测算了不同时期下研究区碳储量情况。结果表明:2007—2017年汾河上游草地、未利用地及水体面积减少,耕地、建设用地、林地增加,自然增长情景与生态保护情景下2030年土地利用格局差异较大,耕地、建设用地、林地及水体呈相反趋势发展。2017年汾河上游生态系统碳储量和碳密度分别为58977910.98t和147.54t/hm²,与2007年相比增加了1237143.02t和3.09t/hm²。2017—2030年自然增长情景下汾河上游生态系统碳储量和碳密度显著下降,主要原因是林地、草地面积减少,建设用地增加,生态保护情景下显著增加,碳储量和碳密度分别为59142210.16t和147.95t/hm²。生态保护情景能够有效提高区域生态系统碳储量,但同时要考虑社会经济可持续发展,因此研究区在未来发展规划中应基于生态保护情景,统筹各项资源,保障经济发展。

Carbon storage assessment in the upper reaches of the Fenhe River under different land use scenarios

Terrestrial ecosystem carbon storage is of great significance for predicting climate change, greenhouse gas emissions and reductions. Land use pattern change is the basis for studying terrestrial ecosystem carbon storage, which directly affects the structure and distribution of terrestrial ecosystems, as well as changes terrestrial ecosystem carbon reserves. Taking the upper Fenhe River as an example, this paper analyzed the land use change from 2007 to 2017, and the SD_CLUE-S composite model was used to simulate the land use pattern under natural growth and ecological protection environment. Based on the land use data, the InVEST model was used to measure the carbon storage of ecosystem in 2007 to 2017 and in the future under different scenarios. The results showed that the area of grass land, unused land and water body in the upper reaches of Fenhe River decreased from 2007 to 2017, while the cultivated land, construction land and forest land increased. The land use pattern in 2030 under natural growth scenarios and ecological protection scenarios was quite different. The cultivated land, construction land, forest land and water body indicated an opposite trend. In 2017, the carbon storage and carbon density of the upper Fenhe ecosystem were 58997910.98 t and 147.54 t/hm², which increased by 1237143.02 t and 3.09 t/hm² compared with 2007. Under the natural growth scenario from 2017 to 2030, the carbon storage and carbon density of the ecosystem in the upper reaches of Fenhe decreased significantly, mainly due to the decrease in forest land and grass land, the increase in construction land, and the significant increase under the ecological protection scenario. The carbon storage and carbon density were 59142210.16 t and 147.95 t/hm², respectively. Ecological protection scenarios can effectively improve the regional ecosystem carbon storage, but at the same time, sustainable social and economic development must be considered. Therefore, in the future development plan, the research area should coordinate various resources based on ecological protection scenarios to ensure economic development.