以广东省海岸带为研究区,基于2005、2010、2015和2020年4期土地利用数据,采用土地利用转移矩阵、景观生态风险指数模型和空间自相关分析等方法,对近15年广东省海岸带土地利用动态特征和景观生态风险进行定量评价,并进一步揭示其时空演...以广东省海岸带为研究区,基于2005、2010、2015和2020年4期土地利用数据,采用土地利用转移矩阵、景观生态风险指数模型和空间自相关分析等方法,对近15年广东省海岸带土地利用动态特征和景观生态风险进行定量评价,并进一步揭示其时空演变特征。结果表明:(1)2005—2020年,广东省海岸带土地利用类型以林地、耕地和建设用地为主,林地和耕地分别占研究区总面积的59%和23%以上;土地利用主要转移特征为建设用地增加了2560.70 km ^(2),其中80.10%由耕地和林地转移而来;(2)近15年来,研究区生态状况以低风险、较低风险和中风险区为主,共占研究区总面积的76%以上,低风险区与较低风险区面积占比由48.79%减少到38.33%,中风险区面积占比由24.16%增加到38.27%;(3)2005—2020年广东省海岸带景观生态风险呈现正相关关系,在空间上呈集聚效应,“高—高”风险区主要分布沿海城市附近,“低—低”风险区主要分布在珠三角城市。研究结果揭示了广东省海岸带土地利用转移特征和景观生态风险时空演变特征,为海岸带土地资源的合理开发、景观格局的优化以及政策制定提供理论依据。展开更多
The geochemical properties of sediment in the nearby seawater areas of Hailing Bay of the western Guangdong province were first time investigated in the dry period of 2001 and the flood period of 2002, respectively. T...The geochemical properties of sediment in the nearby seawater areas of Hailing Bay of the western Guangdong province were first time investigated in the dry period of 2001 and the flood period of 2002, respectively. The temporal and spatial characteristics of Cu, Pb, Zn, Cd and Hg concentrations, organic carbon and total sulfides contents, and granulometric distribution in the surface sediment from the Hailing Bay were analyzed. Results demonstrated that there were no remarkable changes in the composition of sediment between the dry period and the flood period; the average concentrations of Cu, Pb, Zn, Cd and Hg were 32.1 ± 17.5, 36.1 ± 10.0, 107.0 ± 37.4, 0.26± 0.15 and 0.109 ± 0.073 mg·kg-1, respectively; the organic carbon and total sulfides contents were 1.33 ± 0.53 % and 140.13 ± 136.42 mg·kg-1, respectively; surface sediments were dominated by clayey silt and sand, and their mean grain size was 4.62 ± 2.36 φ and in the range 0.52-7.55 φ; there existed obvious correlation between the concentrations of Cu, Pb, Zn and Hg, and among Cu, Pb, Zn and Hg concentrations, organic carbon contents and grain size of sediments.展开更多
文摘以广东省海岸带为研究区,基于2005、2010、2015和2020年4期土地利用数据,采用土地利用转移矩阵、景观生态风险指数模型和空间自相关分析等方法,对近15年广东省海岸带土地利用动态特征和景观生态风险进行定量评价,并进一步揭示其时空演变特征。结果表明:(1)2005—2020年,广东省海岸带土地利用类型以林地、耕地和建设用地为主,林地和耕地分别占研究区总面积的59%和23%以上;土地利用主要转移特征为建设用地增加了2560.70 km ^(2),其中80.10%由耕地和林地转移而来;(2)近15年来,研究区生态状况以低风险、较低风险和中风险区为主,共占研究区总面积的76%以上,低风险区与较低风险区面积占比由48.79%减少到38.33%,中风险区面积占比由24.16%增加到38.27%;(3)2005—2020年广东省海岸带景观生态风险呈现正相关关系,在空间上呈集聚效应,“高—高”风险区主要分布沿海城市附近,“低—低”风险区主要分布在珠三角城市。研究结果揭示了广东省海岸带土地利用转移特征和景观生态风险时空演变特征,为海岸带土地资源的合理开发、景观格局的优化以及政策制定提供理论依据。
文摘The geochemical properties of sediment in the nearby seawater areas of Hailing Bay of the western Guangdong province were first time investigated in the dry period of 2001 and the flood period of 2002, respectively. The temporal and spatial characteristics of Cu, Pb, Zn, Cd and Hg concentrations, organic carbon and total sulfides contents, and granulometric distribution in the surface sediment from the Hailing Bay were analyzed. Results demonstrated that there were no remarkable changes in the composition of sediment between the dry period and the flood period; the average concentrations of Cu, Pb, Zn, Cd and Hg were 32.1 ± 17.5, 36.1 ± 10.0, 107.0 ± 37.4, 0.26± 0.15 and 0.109 ± 0.073 mg·kg-1, respectively; the organic carbon and total sulfides contents were 1.33 ± 0.53 % and 140.13 ± 136.42 mg·kg-1, respectively; surface sediments were dominated by clayey silt and sand, and their mean grain size was 4.62 ± 2.36 φ and in the range 0.52-7.55 φ; there existed obvious correlation between the concentrations of Cu, Pb, Zn and Hg, and among Cu, Pb, Zn and Hg concentrations, organic carbon contents and grain size of sediments.
