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许多土地经营者认为,形成一种新松林唯一可靠的途径,就是通过人工造林。然而还有一种有效的低成本更新方法——天然更新。它借助原林分采伐之前所产生的种子或苗木而形成新的林分。在无天然种子的情况下,也可以直接播种,这就是人工更新。此法所需要的条件和措施与天然更新相似。天然更新方法目前美国南部天然松林更新成功的方法有三种,即母树下种更新法、伞伐更新法,以及用种子或苗木所进行的皆伐更新法。三种更新方法费用低,花工少,不需
Many land managers believe the only credible way of forming a new pine forest is through afforestation. However, there is an effective low-cost update method - natural update. It relies on the seeds or seedlings produced before harvesting of the original stands to form new stands. In the absence of natural seeds, can also be sown directly, this is a manual update. The conditions and measures required for this method are similar to those of natural renewal. Natural regeneration methods At present, there are three methods for the regeneration of natural pine forests in the southern United States, that is, the method of regeneration under the tree, the method of updating the umbrella, and the method of clear cutting by seeds or seedlings. Three methods of updating low cost, less labor, not required