密云水库二级保护区生态承载力研究与分析

［目的］文章针对南调水入密云水库后北京水源地环境保护和生态产业发展之间面临的新的挑战，确定水源保护区具有操作性的承载空间分布和产业规模控制方案，为这一区域持续发展提供决策支持。［方法］通过构建密云水库保护区生态承载与敏感性分析指标、模型及分级标准，提取生态系统敏感和具有关键生态功能的区域，并从生态用地最小范围角度体现区域生态承载力的底线。［结果］（1）密云水库保护区近30年来生态环境保护政策措施实施较好，生态状况较优，生态承载力极度敏感区为零，但是由于库区周边承载了86个村庄、85万人，生态承载能力下降，不敏感区为零，轻度敏感区只占总面积的3%，中高度敏感区域占库区总面积的80%； (2)密云水源保护区高度敏感的区域为12万hm2，包括库区5乡镇的27个村庄，生态承载能力极弱，划定为库区最小生态用地，原则上种植业不使用化肥、农药，不进行规模养殖畜牧业； (3)密云水源保护区中轻度敏感的区域为25万hm2，包括库区7乡镇的59个村庄，生态承载尚有空间，可养殖牛939头、生猪9 599头、羊7 999只、鸡60万只，折合羊单位为36万只，占库区现有养殖总量的32%，需要在现有基础上削减68%。［结论］确定了密云水源保护区生态承载禁限养殖区和非禁限区及其畜禽养殖允许量，而不是一律退出，为该区域健康发展提供了科学参考依据。

STUDY AND ANALYSIS ON ECOLOGICAL CAPACITY OF MIYUN RESERVOIR SECOND PROTECTED AREA

In view of the new challenges between the environmental protection and the development of ecological industry in the water source area of Beijing after the S N water transfer project( Middle Route ), this research aims to determine the minimum range of ecological land and the operational spatial distribution of carrying capacity in Miyun water source, which provides decision support for sustainable development of this region. Through the construction of ecological carrying capacity and sensitivity analysis indicators, models and classification criteria of Miyun Reservoir Reservoir Reserve, the sensitive and key ecological function areas of ecosystem were extracted, and the bottom line of regional ecological carrying capacity was reflected from the perspective of the minimum scope of ecological land use.Results showed that the sensitive area of ecological carrying capacity was zero, so the ecological condition of Miyun Reservoir was better, because of the ecological environmental protection policies and measures had been carried out well in recent 30 years. But because there are still 86 villages and 8 5000 people in Miyun Reservoir protection area, the ecological carrying capacity decreased, the insensitive area of ecological carrying capacity was also zero, the low grade sensitive area of ecological carrying capacity accounted for only 3% of the total areas, the middle and highly sensitive area accounted for 80% of the total areas in Miyun Water Source Protection Area. The highly sensitive area is 12 000 hm2, including Shicheng, Fengjiayu and Bulaotun etc. 5 townships, 27 villages, of which the ecological carrying capacity was very weak, and it was designated as the smallest ecological land in the reservoir areas. In principle, chemical fertilizers, pesticides and livestock raising on a large scale were forbidden; The low grade and middle sensitive area was 25 000 hm2, including 59 villages in 7 townships, of which there was still space for ecological loading. The allowable amounts of ecological carrying capacity for livestock and poultry breeding had been determined, that was 939 cattle, 9 599 pigs, 7 999 sheep, 600 000 chickens and equal to 36 000 sheep units were allowed to be raised in these 59 villages, of which 68% of the current aquaculture industry needs to be reduced to 32% on the existing basis. The results have determined the restricted ecological carrying zone and non prohibited area and also the allowable amount of livestock and poultry breeding in Miyun Water Reservoir, which provides scientific references for the healthy development of this region.