辽河三角洲湿地以丹顶鹤生境保护为核心的退耕预案研究

在遥感 (RS)和地理信息系统 (GIS)的支持下 ,结合野外实地调查 ,运用预案研究方法和景观生态决策与评价支持系统(L EDESS)的决策与规划评价思想 ,针对辽河三角洲大洼小三角洲部分的过度农业开发对野生动物生境的严重影响后果 ,对本区土地利用规划进行了以丹顶鹤生境保护为核心的退耕预案设计 ,并对其生态后果进行了空间模拟和评价。根据不同的经济和生态发展要求设计了 4个预案 ,分别为 1988年原状 (预案 1)、1998年原状 (预案 2 )、苇带设计 (预案 3)和生境恢复 (预案 4 ) ,通过对各预案进行生境适宜性、生态承载力及经济效益评价 ,可以得到以下结论 :预案 1尽管生态效益很高 ,但经济效益很低 ,在区域发展需求下由现状年恢复到预案 1具有不现实性 ;而预案 2为强烈经济需求下的典型发展模式 ,生态效益偏低 ,与经济效益的比例失调 ;预案 3和预案 4为生态与经济的协调发展模式及丹顶鹤生境恢复提供了有效参考 ,可将其视为近期和远期规划目标分步实施。这说明合理的土地开发利用方式和生境恢复措施不仅可以获得经济的高效发展 ,而且还可为稳定的生态环境提供有力保障 ,从而为区域经济与环境的协调发展提供参考性依据 ,具有一定的典型性

Scenarios study on returning farmland to wetlands for protecting red-crowned cranes in the Liaohe Delta

The Liaohe Delta is one of the most important wetlands for wild animals, especially for water birds, to inhabit and breed. It is the southern most site for the breeding of red-crowned cranes (Grus japonensis), and an important stopover site on their migration route. Therefore this delta plays an important role in the international conservation of cranes. But the area of suitable habitat had reduced and the quality of habitat was degraded in the last decades, mainly due to oil and agricultural exploitation. The objective of this research was to find an appropriate land use model to keep economic development and habitat conservation of the region.Based on the study of land use change between 1988 and 1998 in the Liaohe Delta, and supported by intensive field investigation, four land use planning scenarios of the Dawa sub-delta were designed with the scenarios approach and the evaluation idea of LEDESS Model (Landscape Ecological Decision and Evaluation Support System). The four scenarios, Year 1988 (No.1), Year 1998 (No.2), Reed belt (No.3) and Habitat restoration (No.4), were different in the aims of ecological and economic benefit. The main measures were returning paddy fields to reed fields and prawn-crab-ponds to restore the habitat of wild animals. The habitat suitability, the breeding carrying capacity and the economic benefit of different scenarios on the red-crowned crane's habitat were simulated and evaluated with different methods, in which spatial diversity index was adopted to analyze the habitat suitability. The result was that the habitat suitability, the breeding carrying capacity and the economic index were 0.575, 33 pairs and 10.56 respectively in Scenario No.1, 0.357, 22 pairs and 16.68 in Scenario No.2, 0.435, 32 pairs and 17.42 in Scenario No.3, and 0.535, 41 pairs and 17.74 in Scenario No.4. It was concluded that Scenario No.1 was unpractical because of the lowest economic benefit in the four scenarios; Scenario No.2 had high economic benefit but the least ecological benefit, which endangered the suitable habitats of the wild animals; and Scenarios No.3 and No.4 were effective to keep harmonious development between economy and environment, which could be actualized in steps as the short-term and long term planning goals. It was indicated that appropriate land use models and habitat restoration measures could not only keep economic development but also offer a steady habitat for wild animals. This study can serve as a reference to the coordination between economic development and ecological conservation in the Liaohe Delta, as well as other similar area.