大型露天矿区生态修复通过地貌重塑、土壤重构、植被重建与生态恢复等系列工程往往有助于重构区域碳库,特别是植被碳库,但现阶段针对不同生态修复模式的生态系统碳汇功能研究尚存在不足。以重庆市渝北区铜锣山国家矿山公园原损毁矿坑为...大型露天矿区生态修复通过地貌重塑、土壤重构、植被重建与生态恢复等系列工程往往有助于重构区域碳库,特别是植被碳库,但现阶段针对不同生态修复模式的生态系统碳汇功能研究尚存在不足。以重庆市渝北区铜锣山国家矿山公园原损毁矿坑为例,基于GF-6 PMS卫星影像与地面实测数据,通过多种回归模型模拟构建大型露天矿区生态修复植被碳汇模型,对矿区植被生物量与碳储量进行估算,探讨不同修复模式与修复年限的植被碳储量空间分布特征。研究结果表明,基于GF-6 PMS卫星影像提取植被指数,结合野外实地采样数据可以完成大型露天矿区植被地上碳储量的估算,而且基于归一化绿波波段差值植被指数(GNDVI)构建的二次方程模型相关性较好;铜锣山矿区植被平均碳密度为1.84 t C/hm^(2),植被碳储量为408.68 t C,且不同修复模式与修复年限的植被碳储量存在差异,工程修复、自然恢复与关闭未治理矿区的植被平均碳密度分别为2.54、2.09、0.88 t C/hm^(2),工程修复完成1~3年的矿区植被平均碳密度分别为2.75、2.45、2.38 t C/hm^(2),说明工程修复可增加植被固碳效益;不同矿坑类型与修复模式对植被平均碳密度的影响显著,且矿坑类型、修复模式、修复年限均与植被平均碳密度存在显著相关性。研究建立的模型具有一定可靠性,可辅助大尺度植被碳平衡以及评价工作,对于推动中国自主高分卫星数据在生态修复领域应用具有重要意义。展开更多
Land consolidation (LC), as a type of human disturbance, improves land production efficiency and changes landscape distribution through land parcel reallocation. The objective of this study was to comparatively analyz...Land consolidation (LC), as a type of human disturbance, improves land production efficiency and changes landscape distribution through land parcel reallocation. The objective of this study was to comparatively analyze the changes of landscape patches before and after a land consolidation project (LCP) and the effects of land levelling, irrigation and drainage work and road engineering on the landscape structure. FRAGSTAT3.3 and buffer zone analysis were used to investigate those changes. The results suggest that the heterogeneity of landscape depressed, and tended to simplification after LC. Dry land was the most highly variable land use pattern, and the change of forestland was least due to its locations at a gradient larger than 25°. LC resulted in a more rational use of land, and could be an important step in promoting rural development in depressed and fragmented agricultural areas through unused land exploitation, small-patch combination, irrigation and water conservancy, and road construction. Land levelling leveled off the gradient field surface and decreased the slope. The fragmentized patches were much more incorporated with increasing slope. On the other hand, the ridge of a field became longer so that the length of field surface and area of patch were increased. Land levelling regulated, simplified and combined patches, so that the complexity degree was reduced. It is found that the buffer distance of 35 m was a turning point of human disturbance by irrigation and drainage systems, and patches presented flaky distribution when the buffer distance was smaller than 35 m. Meanwhile, the distance range between 25 m to 50 m was an impressible area for road engineering, which was sensitive to human actions, and the changes of all landscape metrics were larger than those in other buffer zones. In general, LC not only reallocated fragmented parcels, but also improved agricultural conditions.展开更多
文摘大型露天矿区生态修复通过地貌重塑、土壤重构、植被重建与生态恢复等系列工程往往有助于重构区域碳库,特别是植被碳库,但现阶段针对不同生态修复模式的生态系统碳汇功能研究尚存在不足。以重庆市渝北区铜锣山国家矿山公园原损毁矿坑为例,基于GF-6 PMS卫星影像与地面实测数据,通过多种回归模型模拟构建大型露天矿区生态修复植被碳汇模型,对矿区植被生物量与碳储量进行估算,探讨不同修复模式与修复年限的植被碳储量空间分布特征。研究结果表明,基于GF-6 PMS卫星影像提取植被指数,结合野外实地采样数据可以完成大型露天矿区植被地上碳储量的估算,而且基于归一化绿波波段差值植被指数(GNDVI)构建的二次方程模型相关性较好;铜锣山矿区植被平均碳密度为1.84 t C/hm^(2),植被碳储量为408.68 t C,且不同修复模式与修复年限的植被碳储量存在差异,工程修复、自然恢复与关闭未治理矿区的植被平均碳密度分别为2.54、2.09、0.88 t C/hm^(2),工程修复完成1~3年的矿区植被平均碳密度分别为2.75、2.45、2.38 t C/hm^(2),说明工程修复可增加植被固碳效益;不同矿坑类型与修复模式对植被平均碳密度的影响显著,且矿坑类型、修复模式、修复年限均与植被平均碳密度存在显著相关性。研究建立的模型具有一定可靠性,可辅助大尺度植被碳平衡以及评价工作,对于推动中国自主高分卫星数据在生态修复领域应用具有重要意义。
基金Funded by the Science and Technology Supporting Plan of China (No. 2006BAD05801-02)
文摘Land consolidation (LC), as a type of human disturbance, improves land production efficiency and changes landscape distribution through land parcel reallocation. The objective of this study was to comparatively analyze the changes of landscape patches before and after a land consolidation project (LCP) and the effects of land levelling, irrigation and drainage work and road engineering on the landscape structure. FRAGSTAT3.3 and buffer zone analysis were used to investigate those changes. The results suggest that the heterogeneity of landscape depressed, and tended to simplification after LC. Dry land was the most highly variable land use pattern, and the change of forestland was least due to its locations at a gradient larger than 25°. LC resulted in a more rational use of land, and could be an important step in promoting rural development in depressed and fragmented agricultural areas through unused land exploitation, small-patch combination, irrigation and water conservancy, and road construction. Land levelling leveled off the gradient field surface and decreased the slope. The fragmentized patches were much more incorporated with increasing slope. On the other hand, the ridge of a field became longer so that the length of field surface and area of patch were increased. Land levelling regulated, simplified and combined patches, so that the complexity degree was reduced. It is found that the buffer distance of 35 m was a turning point of human disturbance by irrigation and drainage systems, and patches presented flaky distribution when the buffer distance was smaller than 35 m. Meanwhile, the distance range between 25 m to 50 m was an impressible area for road engineering, which was sensitive to human actions, and the changes of all landscape metrics were larger than those in other buffer zones. In general, LC not only reallocated fragmented parcels, but also improved agricultural conditions.
