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61.
62.
Simulating the cumulative effects of multiple forest management strategies on landscape measures of forest sustainability 总被引:1,自引:2,他引:1
While the cumulative effects of the actions of multiple owners have long been recognized as critically relevant to efforts
to maintain sustainable forests at the landscape scale, few studies have addressed these effects. We used the HARVEST timber
harvest simulator to predict the cumulative effects of four owner groups (two paper companies, a state forest and non-industrial
private owners) with different management objectives on landscape pattern in an upper Michigan landscape managed primarily
for timber production. We quantified trends in landscape pattern metrics that were linked to Montreal Process indicators of
forest sustainability, and used a simple wildlife habitat model to project habitat trends. Our results showed that most trends
were considered favorable for forest sustainability, but that some were not. The proportion of all age classes and some forest
types moved closer to presettlement conditions. The trend for the size of uneven-aged patches was essentially flat while the
average size of patches of the oldest and youngest age classes increased and the size of patches of the remaining age classes
decreased. Forest fragmentation generally declined, but edge density of age classes increased. Late seral forest habitat increased
while early successional habitat declined. The owners use different management systems that cumulatively produce a diversity
of habitats. Our approach provides a tool to evaluate such cumulative effects on other landscapes owned by multiple owners.
The approach holds promise for helping landowner groups develop and evaluate cooperative strategies to improve landscape patterns
for forest sustainability. 相似文献
63.
Erik Skrbck 《Urban Forestry & Urban Greening》2007,6(4):279-285
Sustainable development requires, among other things, that development projects not result in the degradation of natural resources for outdoor recreation. There has been a rapid increase in knowledge regarding the importance of the external environment to our health and well-being. Stress is reduced significantly when people are exposed to health-promoting nature and landscape values. Many people are actively choosing to reduce their stress. Doctors today prescribe outdoor walks in peaceful environments for the same purpose. A high level of traffic noise increases stress. This paper discusses the application of silent values in an infrastructure development project, the extension of Sturup Airport, east of Malmö, Sweden and Copenhagen, Denmark. Through estimating the change in noise resulting from the development, it is possible to integrate mitigating and compensating measures in the planning process discussions. Such measures can be negotiated as conditions for authorization of the project. The airport is situated in an area rich in nature values for recreation. The airport expansion will mean both new noise impacting "silent" areas and increasing noise levels in already noise-affected areas. In this study, we have taken a positive stand on the silent areas, mostly agriculture land, where compensation measures could be taken, thus balancing the loss of silent nature values for recreation. Silent areas that will not be affected are suitable and feassible for compensation measures thus can be called compensation areas. In this way the development of new recreational areas, preferably designed as urban forests, are critical preconditions for the negotiations for the airport extension. The conclusion is that urban forest investments for health and well-being can be an important part of strategic decisions in spatial planning. As preconditions for a permit, the development and financing of new urban forests and green areas can be part of the total development plan. This is an issue of global interest, as many countries are in a process of rapid urbanization, and urban greening and urban forestry have an important role to play in the process of promoting quality of life and improving environmental quality. 相似文献
64.
Neutral models for testing landscape hypotheses 总被引:5,自引:0,他引:5
Neutral landscape models were originally developed to test the hypothesis that human-induced fragmentation produces patterns
distinctly different from those associated with random processes. Other uses for neutral models have become apparent, including
the development and testing of landscape metrics to characterize landscape pattern. Although metric development proved to
be significant, the focus on metrics obscured the need for iterative hypothesis testing fundamental to the advancement of
the discipline. We present here an example of an alternative neutral model and hypothesis designed to relate the process of
landscape change to observed landscape patterns. The methods and program, QRULE, are described and options for statistical
testing outlined. The results show that human fragmentation of landscapes results in a non-random association of land-cover
types that can be describe by simple statistical methods. Options for additional landscape studies are discussed and access
to QRULE described in the hope that these methods will be employed to advance our understanding of the processes that affect
the structure and function in human dominated landscapes. 相似文献
65.
Empirical relationships between land use/cover and estuarine condition in the Northeastern United States 总被引:1,自引:0,他引:1
Wilfrid Rodriguez Peter V. August Yeqiao Wang John F. Paul Arthur Gold Norman Rubinstein 《Landscape Ecology》2007,22(3):403-417
Land–water interactions were examined in three regions in the Virginian Biogeographic Province; the southern shore of Cape
Cod, Massachusetts; the Hudson/Raritan region of New York; and the eastern shore of the Delmarva (Delaware/Maryland/Virginia)
Peninsula. Cumulative distribution functions were used to evaluate similarity in environmental condition among estuaries.
Spatial-setting variables (location in a river, coastal lagoon, or in open waters) were associated with variation for some
measures of estuarine condition. Patterns of coastal urban and agriculture gradients were measured and their relationship
with indicators of estuarine condition was modeled statistically. When estuaries were pooled, the highest variation explained
by spatial-setting variables was found for dissolved oxygen (DO, R
2 = 0.44) and salinity (R
2 = 0.58), with DO decreasing in river locations and salinity decreasing with rainfall and sampling locations near rivers.
The explanatory power for the other indicator variables was low and varied from 6% to 27%. Rainfall explained some of the
variation (R
2 = 0.23) in total suspended solids. Moderate (0.4 < | r | < 0.7) to strong (| r | ≥ 0.7) linear associations were found between total urban area and measures of estuarine condition. Within regions, total
urban area was positively associated with Silver (r = 0.59), Cadmium (r = 0.65), and Mercury (r = 0.47) in Cape Cod, and inversely related to DO (r = −0.65) in the Hudson/Raritan region. No associations were found in the Delmarva Peninsula study area. Total area of agriculture
showed a moderate association with Arsenic in Cape Cod, but no other associations were found in the other two regions. Our
analyses show a measurable impact of urban land use on coastal ecosystem condition over large areas of the northeastern United
States. This pattern was most evident when many different landscapes were considered simultaneously. The relationship between
urban development and estuarine condition were weaker within the individual regions studied. The use of land use/cover models
for predicting estuarine condition is a challenging task that warrants enhancements in the type, quantity, and quality of
data to improve our ability to discern relationships between anthropogenic activities on land and the condition of coastal
environments. 相似文献
66.
Land use changes operate at different scales. They trigger a cascade of effects that simultaneously modify the composition
or structure of the landscape and of the local vegetation. Mobil animals, and birds in particular, can respond quickly to
such multi-scalar changes. We took advantage of a long term study on the response of songbirds to land-use changes on four
Mediterranean islands in Corsica and Sardinia to explore the benefits of a multi-scale analysis of the relationships between
songbird distribution, vegetation structure and landscape dynamics. Field data and aerial photographs were used to describe
the vegetation at three different scales. Birds were censused by point counts. We used statistical variance decomposition
to study how bird distribution and vegetation at various scales were linked. We analysed multi-scale vegetation changes (floristic
composition, plot vegetation type, and landscape structure) and their consequences on bird distribution with multivariate
and non-parametrical tests. The distribution of most species was linked to at least two spatial scales. The weight of a given
scale was consistent with life-history traits for species whose biology was well-known. In the examples studied, vegetation
composition, vegetation type and landscape changes that resulted from land abandonment negatively affected birds depending
on open or heterogeneous areas. Our results emphasize that multi-scale analyses can greatly enhance our understanding of bird
distribution and of their changes. Management of these populations should take into account measures at various spatial scales
depending on the sensitivity of the species. 相似文献
67.
211省道庆宁至河西段绿化景观设计以“美丽金川、百里画廊”为总体设计理念,其设计理念主要体现在公路的5个主题景观段落中,每个段落确定一个主题和要表达到的意境,按照“梨花春雪三月天,桃红柳绿似江南.一段一景皆有意,百里画廊入梦来.”的设计构思,把公路打造成集塞上江南、高原梨乡、地方文化特色和魅力为一体蕴含丰富景观的风景画卷,以达到丰富公路景观效果,提升公路的绿化档次的目的.本段公路绿化景观化设计为省级公路的绿化设计及建设开创了一个新的思路. 相似文献
68.
现代小区园林景观作为城市居住环境的一个重要组成部分,具有改善小区居民生活环境,提高居民生活质量的重要作用。针对目前许多居住小区仿照西方园林景观设计建造,失去中国传统的园林特色的现状,提出在现代小区园林景观设计中融入中国山水画的元素及天人合一思想的对策。通过分析合肥"世纪阳光花园"现代中式园林景观,探索现代住宅小区园林景观与中国山水画理相融合,营造出源于自然,高于自然的宜居、舒适、诗画般的生活空间的具体方法。 相似文献
69.
Zhang jian-fang 《农业科技与信息》2007,(7)
近年来,一些沿海地区大量引进南洋楹,作为行道树种植。为更好地了解南洋楹的抗风能力,作者于台风"杜鹃"登陆次日对南洋楹的风害情况作了调查统计。结果为南洋楹受到了严重的损害,这证明它不抗强风,易受风折,抗风力属Ⅲ级,因此建议沿海地区的有关绿化部门不宜将南洋楹作为行道树大量种植。 相似文献
70.
Current payment for environmental service (PES) schemes face challenges in the form of evaluation of opportunity costs and ecosystem service delivery, high transaction costs, and difficulties in ensuring conditionality. Even when these conditions are met, PES may be undermined by a lack of inclusivity, leading to societal conflicts over land use. We propose a new PES-type approach that we call Landscape Labelling that seeks to overcome these problems by combining PES and product certification principles applied at a landscape scale with local benefits realized at the community level. 相似文献