ABSTRACT

Stand development in riparian forest buffers was simulated for three forest landscapes in Sweden, using data taken from a sample plot inventory along 38 streams. The objectives were: to quantify the effects on wood production and the economy of management alternatives for buffers; and to evaluate the development of important stand structures for buffer functionality. Buffer widths from 0 to 30 m were analyzed with unmanaged or selective logging as alternatives. Leaving unmanaged buffers resulted in the cost being generally proportional to the area of productive forest land covered by buffers in the landscape. The cost for the widest buffer alternative, 30 m, when left unmanaged, was between 4 and 10% of the total net present value of the entire forest landscape. Allowing selective logging to promote broadleaved trees in the buffer reduced the costs to 1–3% of the net present value. Selective logging increased the volume share of broadleaved trees in the buffer, thus enhancing some of its ecological functions. Unmanaged buffers increased the amount of dead wood more than the alternatives with selective logging. Decisions about buffer zone management must consider the trade-off between economic and environmental benefits, as well as the trade-offs between contrasting environmental goals.

摘要

利用沿38条溪流的样地清单中的数据，对瑞典三处森林景观的河岸森林缓冲区的林分发育进行了模拟。目标是：量化缓冲生产的替代品对木材生产和经济的影响；并评估用于缓冲功能的重要展台结构的开发。分析了0到30 m的缓冲区宽度，并选择了非管理或选择性测井。留下未经管理的缓冲带会导致成本通常与景观缓冲带所覆盖的生产性林地面积成正比。如果不加管理，则最宽的缓冲带30 m的成本占整个森林景观总净现值的4％至10％。允许选择性伐木促进缓冲区中阔叶树的生长，使成本降低至净现值的1-3％。选择性伐木增加了缓冲区中阔叶树的体积份额，从而增强了其某些生态功能。与有选择采伐的替代品相比，无管理的缓冲器增加了死木的数量。有关缓冲区管理的决策必须考虑经济效益与环境效益之间的权衡，以及相互矛盾的环境目标之间的权衡。