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781.
Bryan BA 《Environmental management》2006,37(1):126-140
The desire to capture natural regions in the landscape has been a goal of geographic and environmental classification and ecological land classification (ELC)
for decades. Since the increased adoption of data-centric, multivariate, computational methods, the search for natural regions
has become the search for the best classification that optimally trades off classification complexity for class homogeneity.
In this study, three techniques are investigated for their ability to find the best classification of the physical environments
of the Mt. Lofty Ranges in South Australia: AutoClass-C (a Bayesian classifier), a Kohonen Self-Organising Map neural network,
and a k-means classifier with homogeneity analysis. AutoClass-C is specifically designed to find the classification that optimally
trades off classification complexity for class homogeneity. However, AutoClass analysis was not found to be assumption-free
because it was very sensitive to the user-specified level of relative error of input data. The AutoClass results suggest that
there may be no way of finding the best classification without making critical assumptions as to the level of class heterogeneity
acceptable in the classification when using continuous environmental data. Therefore, rather than relying on adjusting abstract
parameters to arrive at a classification of suitable complexity, it is better to quantify and visualize the data structure
and the relationship between classification complexity and class homogeneity. Individually and when integrated, the Self-Organizing
Map and k-means classification with homogeneity analysis techniques also used in this study facilitate this and provide information
upon which the decision of the scale of classification can be made. It is argued that instead of searching for the elusive
classification of natural regions in the landscape, it is much better to understand and visualize the environmental structure
of the landscape and to use this knowledge to select the best ELC at the required scale of analysis. 相似文献
782.
783.
A Regional Classification Scheme for Estimating Reference Water Quality in Streams Using Land-Use-Adjusted Spatial Regression-Tree Analysis 总被引:1,自引:0,他引:1
Various approaches are used to subdivide large areas into regions containing streams that have similar reference or background
water quality and that respond similarly to different factors. For many applications, such as establishing reference conditions,
it is preferable to use physical characteristics that are not affected by human activities to delineate these regions. However,
most approaches, such as ecoregion classifications, rely on land use to delineate regions or have difficulties compensating
for the effects of land use. Land use not only directly affects water quality, but it is often correlated with the factors
used to define the regions. In this article, we describe modifications to SPARTA (spatial regression-tree analysis), a relatively
new approach applied to water-quality and environmental characteristic data to delineate zones with similar factors affecting
water quality. In this modified approach, land-use-adjusted (residualized) water quality and environmental characteristics
are computed for each site. Regression-tree analysis is applied to the residualized data to determine the most statistically
important environmental characteristics describing the distribution of a specific water-quality constituent. Geographic information
for small basins throughout the study area is then used to subdivide the area into relatively homogeneous environmental water-quality
zones. For each zone, commonly used approaches are subsequently used to define its reference water quality and how its water
quality responds to changes in land use. SPARTA is used to delineate zones of similar reference concentrations of total phosphorus
and suspended sediment throughout the upper Midwestern part of the United States. 相似文献
784.
Shevchenko Pavel V. Murakami Daisuke Matsui Tomoko Myrvoll Tor A. 《Environmental Economics and Policy Studies》2022,24(3):459-476
Environmental Economics and Policy Studies - The classical DICE model is a widely accepted integrated assessment model for the joint modeling of economic and climate systems, where all model state... 相似文献
785.
Ormbsby Alison A. Felardo Jeff Musci Robert 《Environment, Development and Sustainability》2021,23(8):11636-11645
Environment, Development and Sustainability - Local residents near forests often collect non-timber forest products (NTFPs) for a variety of reasons, including food, medicine, firewood, religious... 相似文献
786.
Russian Journal of Ecology - The long-term dynamics (over more than 70 years) of pike infection by cestodes Triaenophorus crassus and T. nodulosus in the Rybinsk Reservoir (the Volga River) has... 相似文献
787.
Environment, Development and Sustainability - Good air quality is highly essential to the well-being of mankind, all living organisms and the environment. The quality of air is degrading at a... 相似文献
788.
Hewitt Richard J. Pera Florencia A. Garca-Martn Mara Gaudry-Sada Karl-Heinz Hernndez-Jimnez Vernica Bieling Claudia 《Environmental management》2020,65(3):334-354
Environmental Management - Landscapes are changing, with rural areas becoming increasingly urbanized. Children and adolescents are underrepresented in the sense-of-place literature. Our study aimed... 相似文献
789.
Robert A. Montgomery Madeline Carr Charlie R. Booher Abigail M. Pointer Brendan M. Mitchell Natalie Smith Keegan Calnan Georgina M. Montgomery Mordecai Ogada Daniel B. Kramer 《Conservation biology》2020,34(4):915-924
In November 1928, Theodore Jr. and Kermit Roosevelt led an expedition to China with the expressed purpose of being the first Westerners to kill the giant panda (Ailuropoda melanoleuca). The expedition lasted 8 months and resulted in the brothers shooting a giant panda in the mountains of Sichuan Province. Given the concurrent attention in the popular press describing this celebrated expedition, the giant panda was poised to be trophy hunted much like other large mammals around the world. Today, however, the killing of giant pandas, even for the generation of conservation revenue, is unthinkable for reasons related to the species itself and the context, in time and space, in which the species was popularized in the West. We found that the giant panda's status as a conservation symbol, exceptional charisma and gentle disposition, rarity, value as a nonconsumptive ecotourism attraction, and endemism are integral to the explanation of why the species is not trophy hunted. We compared these intrinsic and extrinsic characteristics with 20 of the most common trophy-hunted mammals to determine whether the principles applying to giant pandas are generalizable to other species. Although certain characteristics of the 20 trophy-hunted mammals aligned with the giant panda, many did not. Charisma, economic value, and endemism, in particular, were comparatively unique to the giant panda. Our analysis suggests that, at present, exceptional characteristics may be necessary for certain mammals to be excepted from trophy hunting. However, because discourse relating to the role of trophy hunting in supporting conservation outcomes is dynamic in both science and society, we suspect these valuations will also change in future. 相似文献
790.
Robert A. Montgomery Kendi Borona Herbert Kasozi Tutilo Mudumba Mordecai Ogada 《Conservation biology》2020,34(5):1122-1130
Conservation projects subscribing to a community-based paradigm have predominated in the 21st century. We examined the context in which the phrase was coined and traced its growth over time. Community-based conservation first appeared in the literature in the early 1990s; but grew little until after the 5th World Parks Congress in 2003. Thereafter, publications describing community-based conservation approaches increased exponentially. The conference theme was Benefits Beyond Boundaries, and its goal was to provide an economic model based on revenue accrued from conservation fundraising and ecotourism to support ecosystems, wildlife, and people, particularly in the Global South. Such models tended not to incorporate, as a core principle, the heritage of local human communities. Human heritage varies substantially over time and space making generalization of conservation principles across scales challenging. Pitfalls that have grown out of the community-based conservation approaches in the Global South include fortress conservation, conservation militarism, consumptive and nonconsumptive ecotourism, and whiz-bang solutions. We propose 10 tenets in a human heritage-centered conservation framework (e.g., engage in conservation practices using local languages, thoughtfully propose and apply solutions consistent with human heritage, provide clear professional development pathways for individuals from local communities, and promote alternative revenue-generating programs centered in local communities, among others). Progressive philosophies can derive from authentic and ethical integration of local communities in conservation practice. 相似文献