海南热带雨林国家公园道路分布及其对景观完整性的影响

为揭示高速公路、国道、省道等不同类型道路对海南热带雨林国家公园生态系统完整性和景观格局的影响，选取2000、2010和2019年海南热带雨林国家公园涉及的道路分布和土地利用数据，运用缓冲区分析法获取不同等级道路两侧的景观变化趋势。结果表明:(1) 2000—2019年，海南热带雨林国家公园内道路长度增加2 134.6 km，道路密度增加了0.500 km·km?2。2010年，乡道及以下道路长度增加2 030 km；2019年，新增高速公路，省道310升级为国道361。(2) 高速公路、国道、省道两侧的斑块密度指数及景观形状指数分别在0～500 、0～300和0～250 m范围呈下降趋势，随后趋向于平缓，聚集度指数则表现相反；高速公路、国道、省道的最大影响范围分别为500 、300和250 m。(3) 2000—2019年，道路影响范围内的耕地、有林地、草地、疏林地面积减少，其中高速公路、省道附近的有林地、草地面积降幅最大，国道附近的耕地面积降幅最大；水域、灌木林、建设用地、其他林地(含果园)面积增加，高速公路、国道、省道周边的其他林地(含果园)面积增幅最大。(4) 道路影响范围内，景观形状指数、斑块密度指数和分离度指数略有增加，蔓延度指数则稍有下降；目前道路对国家公园景观的影响较小，但由于道路存在较明显的累加效应及传播作用，仍然需要注意道路对国家公园生态系统原真性和完整性的可能影响，建议加强大型道路如高速公路道路径流的汇流与净化、道路两侧生态廊道、长期环境监测等方面的研究。

Distribution pattern of roads and its impact on landscape integrity in Hainan Tropical Rainforest National Park

Hainan Tropical Rainforest National Park is one of the first national parks officially established in China, and it is also the only national park with expressway in China. In order to reveal the possible impact of the expressway and other roads on landscape patterns and integrity of ecosystem of the national park, the landscape change trend of different level of roads, the influence on the integrity of the ecosystem and the landscape pattern caused by expressway, national road and provincial road were analyzed by using buffer zone analysis method based on the road distribution and land use data in 2000, 2010, and 2019 (the expressway completed). The analysis show that the road length and density in national parks increased by 2, 134.6 km and 0.500 km/km2 in the national park from 2000 to 2019, respectively. The length of rural and other smaller roads increased by 2030 km from 2000 to 2010. The expressway was completed and the Provincial Road 310 was upgraded to the National Road 361 in 2019. A descent of the patch density index (PD) and landscape shape index (LSI) and an ascent of the aggregation index (AI) on both sides of the expressway, national road and provincial road were observed in the range of 0 ~ 500 m, 0 ~ 300 m and 0 ~ 250 m, respectively, followed by a gentle movement. The maximum influence ranges for the expressway, national road and provincial road were 500 m, 300 m and 250 m, respectively. The area of cultivated land, woodland, grassland and open forest land decreased within the area affected by roads; the area of woodland and grassland near expressway and provincial road, and the area of cultivated land near national road showed the greatest descent; the area of water, shrub land, construction land and other woodland (including the orchards) increased; the area of other woodland (including the orchards) around expressway, national road, and provincial road showed the greatest ascent from 2000 to 2019. Within the influence range of roads, LSI index, PD index and splitting index (SPLIT) increased slightly, while contagion index (CONTAG) and AI decreased slightly. At present, roads have a slight effect on the landscape of the national park. However, it is still necessary to pay attention to the possible impact of roads on the authenticity and integrity of the national park ecosystem, which may be affected by the obvious cumulative effect and spreading effect of roads. It is recommended that further research is needed on the confluence and purification of the runoff from large roads such as expressway, building of ecological corridors on both sides of the roads, long-term environmental monitoring, etc.