Ribe Robert G
Department of Landscape Architecture, Institute for a Sustainable Environment, 5234 University of Oregon, Eugene, OR 97403, USA.
J Environ Manage. 2009 Oct;91(1):245-60. doi: 10.1016/j.jenvman.2009.08.014. Epub 2009 Sep 23.
Tensions between amenity- and timber-based economies in the U.S. and Canadian Pacific Northwest motivated a study of scenic beauty inside mature forests and timber harvests. A diverse sample of regional forests, measures of forest structure, and large, representative samples of photographs and public judges were employed to measure scenic beauty inside un-harvested mature and old-growth forests, and timber harvests. The latter varied systematically in down wood levels and retention level and pattern. Scenic beauty tended to be optimized at a basal area of 110-155 m(3)/ha and/or 700-900 trees/ha. Older forests and those with larger trees were perceived to be more beautiful. In harvests, greater retention levels, less down wood, and dispersed rather than aggregated retention patterns contributed to aesthetic improvements. Green-tree retention harvests offer considerable potential gains in perceived scenic beauty compared to perceived very ugly clearcuts, particularly at higher retention levels. These gains are more reliable from dispersed retention patterns. The silvicultural parameters studied change strength in affecting scenic beauty with changes in retention level. These interactions are explored in relation to a range of scenic quality objectives as an aid to planners, visual impact analysts, and silviculturists.
美国和加拿大太平洋西北地区以休闲为导向的经济与以木材为基础的经济之间的紧张关系,促使人们对成熟森林和木材采伐区域内的景观美感进行研究。研究采用了该地区多样化的森林样本、森林结构测量方法,以及大量具有代表性的照片样本和公众评委,来评估未采伐的成熟林和原始林中以及木材采伐区域内的景观美感。后者在倒木水平以及保留水平和模式方面存在系统差异。景观美感往往在基部面积为110 - 155立方米/公顷和/或700 - 900株/公顷时达到最佳。年代更久的森林以及树木更大的森林被认为更具美感。在采伐区域,更高的保留水平、更少的倒木以及分散而非聚集的保留模式有助于提升美学效果。与被认为非常难看的皆伐地相比,保留活立木的采伐方式在景观美感方面具有显著的潜在提升空间,尤其是在更高的保留水平下。这些提升在分散的保留模式下更为可靠。所研究的造林参数对景观美感的影响强度会随着保留水平的变化而改变。针对一系列景观质量目标探讨了这些相互作用,以帮助规划者、视觉影响分析师和造林学家。