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61.
The degeneration of forest landscapes is mainly caused by human impact on the natural environment, which is posing a great
threat to biodiversity. We studied the relationship between forest landscapes and birds in mountain regions of Xishuangbanna,
Yunnan Province. In Jinuo ethnic region, forest landscape is degenerating, and bird diversity is reducing as a result of human
influence. However, in Hani ethnic region of Mengsong area, a comparative study area, there are also traditional practices
of agriculture and forestry. The traditional practices are dynamically adaptive to local geographic environment and social
economic conditions. A great deal of biodiversity exists in the place where people have lived for many generations and use
the resources of environment in a sustainable manner. Considering bird diversity and forest landscape of mountainous area,
both economic and ecological benefits should be taken into account, which relate to land use and landscape protection. Biodiversity
conservation, resource management and policy making should pay much attention to the best interconnection of land use and
landscapes protection. 相似文献
62.
Urban parks as shared spaces? The utility of alert distances as indicators of avian tolerance of humans in Stirling, Scotland 总被引：3，自引：0，他引：3
Michael O'Neal Campbell 《Area》2006,38(3):301-311
Urban avian foraging is strongly affected by approaching people. Avian alert distances, the instant of a bird's appraisal of human intrusion, have not been studied in a comparative mode for passerines, despite their prominent ecological importance in parks. Alert distances for 13 passerines were examined in parks in Stirling, Scotland, using an innovative approach emphasizing human behaviour and periods between alert and flight distances, termed alert periods. Larger species were less tolerant of humans, although attracted to human wastes. Alert distances also varied according to vegetation variation. Park design may use alert distances to plan vegetation layout as well as reduce disturbing human behaviour. 相似文献
63.
针对海洋地震拖缆系统上位机对多个“水鸟”的控制问题,选取一种海上常见避险工况,对该工况进行分析计算,建立数学模型并利用“罚函数法”进行约束处理,得出基于遗传算法的适应度函数,并提出适用于该类工况一般情况的适应度函数公式,该公式能够完成对该工况所有情形的控制。实例表明该方法易于操作,计算得出的结果符合控制要求。 相似文献
64.
65.
鸭绿江口湿地恢复对迁徙涉禽保护的影响分析 总被引：1，自引：0，他引：1
本文通过对鸭绿江口湿地如何开展人工湿地恢复工作,以及湿地恢复后迁徙涉禽在这一区域的数量、种类以及繁育的变化情况的调查,详细分析了湿地恢复对迁徙涉禽保护的影响,并提出鸭绿江口湿地恢复合理化建议。 相似文献
66.
研究了在不同形式人类经济活动下的森林景观变化与西双版纳地区鸟类多样性的关系．同时对发展生产时的用地布局和维护森林景观的动态发展与提高人们生活质量和持续发展的关系进行了讨论． 相似文献
67.
68.
以琼东南深海三维地震资料为例，全面分析深海地震资料特点，深入分析深海干扰波的类型和特点。针对不同类型的干扰波，采用不同的处理方法，开展针对深海地震资料叠前去噪处理技术研究。通过研究深海地震多次波压制、水鸟干扰压制、涌浪干扰和异常振幅压制等处理方法，总结出针对深海地震资料的叠前去噪技术，为今后的深海地震资料处理工作奠定了技术基础。 相似文献
69.
Lichens are among the main primary colonists in most terrestrial ecosystems of Antarctica, where the effects of environmental factors on spatial distribution of lichens are essential to understanding the functioning of Antarctic terrestrial ecosystems. We measured abundance of 10 frequently observed macrolichens and 15 environmental factors at a small scale （20 cm× 20 cm）, in the ice-free areas of Fildes Peninsula and Ardley Island, King George Island, West Antarctica, and assessed the effects of environmental factors on the local distribution of these lichens. Canonical correspondence analyses （CCA） show that 8 out of 15 environmental factors, belonging to 4 sets of variables, are important in spatial distribution of the 10 lichens. Variation partitioning analyses show that most of the variation in distribution of the 10 lichens is described by the spatial heterogeneity of substrate, bird influence and microclimate and topography, whereas human impact has no significant effects. 相似文献
70.
