环渤海沿海地区土地承载力时空分异特征

沿海地区是中国未来社会经济发展的重点区域,近年来沿海地区人地矛盾越来越突出,研究沿海地区土地承载力具有重要意义。针对以往评价中的不足,采用韦伯-费希纳定律确定指标评价标准;利用D-S证据理论进行主客观综合权重的计算,运用可变模糊集理论及模型对土地承载力进行综合评价,并以环渤海沿海地区进行实例分析。研究结果表明,2000—2011年,环渤海地区土地承载力整体呈持续上升趋势,但空间分布差异显著,天津、唐山、大连、盘锦、青岛、烟台、东营、威海土地承载力相对较高,锦州、营口、秦皇岛、滨州、潍坊、日照属于中等水平,沧州、丹东、葫芦岛四市土地承载力相对较低。可变模糊评价模型应用于土地承载力评价,计算简便,可操作性强,评价结果可信度高。

Land carrying capacity spatiotemporal differentiation in the Bohai Sea Coastal Areas

The study of land carrying capacity is important for coordinating the development of resources, environment, and the economy. This carrying capacity is an important element in the study of regional sustainable development. Coastal areas have the greatest populations, highest population densities, rich resources, and convenient transportation. As in other coastal countries, the coastal area of China is the most developed part of the country. With the acceleration of urbanization, population and economic activity are strongly agglomerating in these coastal areas, resulting in a series of land use conflicts. With such tremendous growth of the economy and society, the conflict between supply and demand of land resources has become increasingly acute. Unreasonable and excessive use of land resources has caused serious damage to the ecological environment of coastal areas and a degradation of land resources. Study on the land carrying capacity of the Bohai Sea coastal areas has great significance for the sustainable development of the Bohai Sea economic circle. The land resource system is complex and has openness, dynamics, social and other characteristics. Therefore, it is difficult to accurately quantify the population, environment, and socioeconomic development. It is also difficult to quantify limits on the land carrying capacity. However, by constructing an indicator system, we can measure dynamic trends and relative land carrying capacity, thereby guiding land use activities. Land carrying capacity assessment is a comprehensive evaluation that involves multiple factors, including natural, social, economic, technological, and others. These factors are interconnected and place mutual restrictions on each other. Relationships between these factors are complex. There is vagueness and uncertainty, as well as dynamic variability under certain temporal and spatial conditions. To date, studies on land carrying capacity have mostly concentrated on inland and ecologically vulnerable areas. There is little research on land carrying capacity in coastal areas. Further, classification standards of assessment indexes in variable fuzzy assessment are mostly determined with reference to relevant statistical data and existing standards. There is a certain subjectivity and arbitrariness, along with inaccuracies. In view of the limitations of prior studies, this work applied the Weber-Fischna law to determine classification standards of assessment indexes. We also used D-S evidential theory to combine subjective factor weights and objective weights to make integrated weights more reliable and accurate. The variable fuzzy assessment method was used to assess comprehensive land carrying capacity in the Bohai Sea coastal areas. Results for those areas show that the land carrying capacity of seventeen cities from 2000 to 2011 had an upward trend on the whole, along with obvious spatial distribution differences. There were higher land carrying capacities at Tianjin, Tangshan, Dalian, Panjin, Qingdao, Dongying, Yantai, and Weihai. Those capacities at Jinzhou, Yingkou, Qinhuangdao, Binzhou, Weifang, and Rizhao were at a medium level, and those at Cangzhou, Dandong, and Huludao were relatively low. The economic development level had strong effects on land carrying capacity. An appropriate economic scale and structure is conducive to sustainable and intensive land use. Application of the variable fuzzy assessment model to land carrying capacity is characterized by simple calculation, ease of operation, and reliable results.