论林木引种与森林可持续经营

森林是实现环境与发展相统一的关键和纽带，在实现国家可持续发展中具有不可替代的作用。外来树种是森林遗传资源的重要组成部分，具有一些乡土树种难以替代的优势。外来树种人工林可持续经营的核心问题是树种与种源的正确选择，为此，保存和丰富必要的基因资源就显得极为重要。外来树种具有一定程度的环境风险，但并没有人们想象的那样大。对当地生物多样性的影响有利有弊，关键是如何科学运作，包括确定合适的地域范围，与乡土树种的合理空间布局，以及如何使之在当地生态系统中形成密不可分的生物链。最危险的情况出现于因检疫不严而带来的病虫危害。

Sustainable Management of Exotic Plantation Forests

Exotic tree species are components of forest genetic resources and play an increasingly important role in the development of commercial plantation forests,in particular,in the tropics and subtropics.Of over 1 000 exotic species introduced into China,a few have been used in the establishment of plantations in huge area for wood production.Compared with indigenous species exotics have some advantages in plantation productivity and stand management,on the other hand,also have great risks if exotic forest genetic resources is not properly managed and used.The major risks in exotic forestry are not caused by the ecotics themselves but the abusive uses of exotic forest gene resources.These exotic plantation forests are more concerned with sustainable forest management to which species selection is crucial,even the issues with disease,land deterioration and biological diversity depletion are also closely related to the sustainability of exotic forest management.To follow the sustainable forest management,exotic forest plantations must be managed in harmony with surrounding forest ecosystems which consist of local flora and fauna.