南宋森林覆盖率及其变迁原因研究

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中国历史上曾经是一个多林的国家,经考证分析在4000年前的远古时代,森林覆盖率高达57%左右。其中,东南部地区森林覆盖率高达80%—90%,部分地区甚至高达90%以上;西北地区的森林覆盖率则在26%以下。随着人类社会历史的发展,不仅森林资源日趋减少,森林结构及其地域分布也不断变化。到公元1000年左右的北宋前期与1200年前后的南宋中后期,森林覆盖率整体分别降低到42%与40%左右。但仅从南宋所辖政区范围约205万平方千米计,森林覆盖率当时则仍高达65%左右。不过,即使在南宋境内,其不同地区森林覆盖率的分布及其变化也有较大的差别。造成南宋不同地区森林覆盖率分布变化的主要原因依次是毁林垦荒,建筑用材,薪炭消耗,车船、家具、农具与棺椁等各种木器制作,矿冶、煮盐与烧制瓷器用材,栈道修建与战乱伐木对森林的砍伐等。从整体的生态环境状态看,南宋仍然处于相对良好的生态系统平衡阶段。 In history, China was once a multi-forest country. After researching and analyzing the ancient times 4000 years ago, the forest coverage rate was as high as 57%. Among them, the southeast of the forest coverage rate as high as 80% -90%, even as high as 90% in some areas; northwest forest cover is below 26%. With the development of human society and history, not only the forest resources have been declining but also the forest structure and its geographical distribution have been constantly changing. By the middle of the Southern Song Dynasty around the early Northern Song Dynasty around 1200 BC and around 1200 BC, the forest cover rate decreased to 42% and 40% respectively. However, only covering an area of ​​about 2.05 million square kilometers under the jurisdiction of the Southern Song Dynasty, the forest coverage rate was still as high as 65% at the time. However, even in the territory of the Southern Song Dynasty, the distribution and changes of forest cover in different regions are also quite different. The main causes of the forest cover change in different regions of the Southern Song Dynasty were as follows: deforestation reclamation, building materials, fuel consumption, vehicles, ships, furniture, tools and coffins and other wood making, mining and metallurgy, cooking salt and porcelain ware, With war logging felling of the forest and so on. From the overall state of ecological environment, the Southern Song Dynasty is still in a relatively good stage of ecosystem balance.
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