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1.
Assessment of Coastal Vulnerability Through the Use of GIS Tools in South Sicily (Italy) 总被引:1,自引:0,他引:1
This study assessed coastal erosion vulnerability along a 90-km sector, which included both erosional and accretionary beaches,
and different levels of human occupation. Two aerial photogrammetric flights were used to reconstruct coastal evolution between
1977 and 1999. During this period, extensive accretion was recorded updrift of human structures at harbors and ports, e.g.,
Scoglitti (105.6 m), Donnalucata (52.8 m), and Pozzallo (94.6 m). Conversely, erosion was recorded in downdrift areas, with
maximum values at Modica Stream mouth (63.8 m) and Point Castellazzo (35.2 m). Assessments were subsequently divided into
four categories ranging from “high erosion” to “accretion.” Several sources were examined to assess human activities and land
use. The latter was mapped and divided into four categories, ranging from “very high” to “no capital” land use. Subsequently,
coastal erosion vulnerability was assessed by combining land use categories with recorded coastline behavior. Results showed
“very high” to “high” vulnerability along 5.8% and 16.6%, respectively, of the littoral, while 20.9% and 56.7%, respectively,
was found to exhibit “medium” and “low/very low” vulnerability. A very good agreement between predicted coastal vulnerability
and coastal trend had been observed over recent years. Furthermore, several human structures and activities are located within
the “imminent collapse zone (ICZ)” which reached maximum values of 17.5 m at Modica Stream and 13.5 m at Point Braccetto. 相似文献
2.
Comparison of Two Spatial Optimization Techniques: A Framework to Solve Multiobjective Land Use Distribution Problems 总被引:1,自引:0,他引:1
Burghard Christian Meyer Jean-Marie Lescot Ramon Laplana 《Environmental management》2009,43(2):264-281
Two spatial optimization approaches, developed from the opposing perspectives of ecological economics and landscape planning
and aimed at the definition of new distributions of farming systems and of land use elements, are compared and integrated
into a general framework. The first approach, applied to a small river catchment in southwestern France, uses SWAT (Soil and
Water Assessment Tool) and a weighted goal programming model in combination with a geographical information system (GIS) for
the determination of optimal farming system patterns, based on selected objective functions to minimize deviations from the
goals of reducing nitrogen and maintaining income. The second approach, demonstrated in a suburban landscape near Leipzig,
Germany, defines a GIS-based predictive habitat model for the search of unfragmented regions suitable for hare populations
(Lepus europaeus), followed by compromise optimization with the aim of planning a new habitat structure distribution for the hare. The multifunctional
problem is solved by the integration of the three landscape functions (“production of cereals,” “resistance to soil erosion
by water,” and “landscape water retention”). Through the comparison, we propose a framework for the definition of optimal
land use patterns based on optimization techniques. The framework includes the main aspects to solve land use distribution
problems with the aim of finding the optimal or best land use decisions. It integrates indicators, goals of spatial developments
and stakeholders, including weighting, and model tools for the prediction of objective functions and risk assessments. Methodological
limits of the uncertainty of data and model outcomes are stressed. The framework clarifies the use of optimization techniques
in spatial planning. 相似文献
3.
Rapid growth in marine sand mining for construction and other uses poses environmental challenges to coastal nations virtually
worldwide. Yet the development of management policies, such as a system of fees imposed on operators for damage caused by
mining, has been frustrated by a lack of studies to support such measures. Adapting a Beverton-Holt bioeconomic model, this
paper attempts to contribute to the estimation of external costs to commercial fisheries due to marine mining. Using the major
mining area of Ongjin in Korea as a case study, we estimate economic losses in use value of commercial fisheries through the
time to recovery of the injured resource stocks. Present value of lost catch over a 1-year period from mining to resource
recovery is estimated at $38,851 for a single “prototype” mining site. Estimated cumulative damages due to recurring mining
for 5 and 10 years are $1.5 million and $2.2 million, respectively, at 20 mining sites. Sensitivity analyses are used to examine
the effects of alternative assumptions to assess the many sources of uncertainty. Using a form of meta-analysis, dose-response
information is used to assess the excess mortality the mining sediment plume has on eggs and larvae and, ultimately, on the
value of lost catch ($841). Also addressed is the importance of specifying the appropriate “premining” conditions against
which to assess environmental losses at the mining site. Damages estimated with premining fish populations are $23,066 higher
than is the case using postmining conditions. Overall, the illustrative results suggest the variety of complex conditions
which influence damage to fisheries from mining and which can benefit from further study to improve management guidelines.
An erratum to this article can be found at 相似文献
4.
Strategic land retirement in agricultural settings has been used as one way to achieve a combination of social objectives,
which include ameliorating water quality problems and enhancing existing systems of wildlife habitat. This study uses a simulation
model operating on a virtual landscape, along with the compromise programming method, to illustrate the implications of alternative
weighting schemes for the long-term performance of the landscape toward various objectives. The analysis suggests that particular
spatial patterns may be related to how various objectives are weighted. The analysis also illustrates the inevitable trade-offs
among objectives, although it may be tempting to present retirement strategies as “win-win.” 相似文献
5.
Pimp Your Landscape: A Tool for Qualitative Evaluation of the Effects of Regional Planning Measures on Ecosystem Services 总被引:1,自引:0,他引:1
The article presents the platform “Pimp your landscape” (PYL), which aims firstly at the support of planners by simulating
alternative land-use scenarios and by an evaluation of benefits or risks for regionally important ecosystem services. Second,
PYL supports an integration of information on environmental and landscape conditions into impact assessment. Third, PYL supports
the integration of impacts of planning measures on ecosystem services. PYL is a modified 2-D cellular automaton with GIS features.
The cells have the major attribute “land-use type” and can be supplemented with additional information, such as specifics
regarding geology, topography and climate. The GIS features support the delineation of non-cellular infrastructural elements,
such as roads or water bodies. An evaluation matrix represents the core element of the system. In this matrix, values in a
relative scale from 0 (lowest value) to 100 (highest value) are assigned to the land-use types and infrastructural elements
depending on their effect on ecosystem services. The option to configure rules for describing the impact of environmental
attributes and proximity effects on cell values and land-use transition probabilities is of particular importance. User interface
and usage of the platform are demonstrated by an application case. Constraints and limits of the recent version are discussed,
including the need to consider in the evaluation, landscape-structure aspects such as patch size, fragmentation and spatial
connectivity. Regarding the further development, it is planned to include the impact of land management practices to support
climate change adaptation and mitigation strategies in regional planning. 相似文献
6.
XU JIONGXIN 《Environmental management》2001,28(1):101-113
In recent years, the desiccation of the lower Yellow River has raised concerns in the government, public, and scientific community
in China. Long-term and widespread desiccation of rivers is a disaster with many adverse environmental implications. It has
been found in this study that there exists a high-frequency zone of river desiccation disasters at 34°–42°N in the North China
Plain. The hazardous environment is characterized by semiarid climate, widely distributed thick loess in the basin and a “hanging
river bed” in the plain as well as unfavorable man–water–land coupling relationships. In this setting, the sharply increased
water diversion by man since the late 1950s led to the occurrence of river desiccation disasters in the lower reaches of the
river in this area. 相似文献
7.
Richard A. Andrews Richard R. Weyrick 《Journal of the American Water Resources Association》1973,9(2):258-272
ABSTRACT A linear programming model for a river basin was developed to include almost all water-related economic activity both for consumers and producers. The model was so designated that the entire basin or basin sub-division could be analyzed. The model included seven sectors, nine objective function criteria, and three river-flow levels. Economic basis for conflicts among sectors over incidence of cost allocation and level of economic activity can be traced to some chosen objective. The disposal of untreated household waste water, particularly from the rural household, directly into the river was consistent with maximizing net benefits and minimizing costs. The optimum resource allocation, water-treatment plants, farms and industry activities would change with flow level. For each of the three industries analyzed separately, paper, wool and tanning, public treatment of industrial waste water was the optimal treatment process in one or more of the solutions. Lake shoreline was the dominant feature determining lake-resource valuation. Implied capital value varied from $126 per shoreline foot to over $250 depending on discount rate. Implied prices on lake surface ranged from $42 to $147 per acre. Strong economic forces encouraged small lot sizes for vacation cottages. 相似文献
8.
The history of the establishment and management philosophies of the mainland Portuguese Protected Areas was reconstructed
through the use of written records and oral history interviews. The objectives were to review the main philosophies in the
creation and management of these areas, to assess the influence of international PA models, to compare the Portuguese case
with other European and international literature concerning PAs and to discuss the value of the oral history in this research.
As main results, it was found that the initial management model of “Wilderness (or Yellowstone)” was replaced by the “new
paradigm” of PAs when the democracy was re-established. Changes in the management philosophies within this “new paradigm”
were also identified, which resulted in the transition of a “Landscape” to a “Nature conservation” model. After the establishment
of the Natura 2000 network, the “Biodiversity conservation” model prevailed. It was also found that the initiative for the
establishment of most PAs came from the government, although there were few cases of creation due to the action of NGOs and
municipalities. Finally, oral history interviews enabled the addition of information to the literature review, but also provided
more insight and detail to this history. 相似文献
9.
H. I. Nightingale J. E. Ayars R. L. McCormick D. C. Cehrs 《Journal of the American Water Resources Association》1983,19(3):429-437
From 1971-1980, studies were conducted at Fresno, California, to identify and quantify, where possible, the soil and water chemistry, subsurface geologic, hydrologic, biologic, and operational factors that determine the long term (10-year) effectiveness of basin type artificial ground water recharge through alluvial soils. This paper updates previous findings and refers to publications that describe the geology beneath the basins and regional geology that determine the transmission and storage properties for local ground water management and chemical quality enhancement. High quality irrigation water from the Kings River was used for recharge. Construction and land costs for the present expanded facility 83 ha (205.2 ac) using three parcels of land were $1,457,100. The nine-year annual mean costs for only canal water, maintenance, and operation were $110.42/ha·m ($13.62/ac·ft) based on an average recharge rate of 1338 ha·m/yr (10,848 ac·ft/yr) at 86 percent facility efficiency. The measured end of season recharge rate averaged 14.97 ± 0.24 cm/day. The 10-year mean actual recharge rate based on actual water delivered, total ponded area, and total days of recharge was 12.1 cm/day. 相似文献
10.
How integrated is river basin management? 总被引:2,自引:0,他引:2
Land and water management is increasingly focused upon the drainage basin. Thirty-six terms recently used for schemes of “integrated
basin management” include reference to the subject or area and to the aims of integrated river basin management, often without
allusion to the multiobjective nature. Diversity in usage of terms has occurred because of the involvement of different disciplines,
of the increasing coherence of the drainage basin approach, and the problems posed in particular parts of the world. The components
included in 21 different approaches are analyzed, and, in addition to showing that components related broadly to water supply,
river channel, land, and leisure aspects, it is concluded that there are essentially five interrelated facets of integrated
basin management that involved water, channel, land, ecology, and human activity. Two aspects not fully included in many previous
schemes concern river channel changes and the dynamic integrity of the fluvial system. To clarify the terminology used, it
is suggested that the termcomprehensive river basin management should be used where a wide range of components is involved, whereasintegrated basin management can signify the interactions of components and the dominance of certain components in the particular area.Holistic river basin management is advocated as a term representing an approach that is both fully comprehensive and integrated but also embraces the energetics
of the river system and consideration of changes of river channels and of human impacts throughout the river system. The paradigm
of working with the river can be extended to one of working with the river in the holistic basin context. 相似文献
11.
Kepe T 《Environmental management》2008,41(3):311-321
Comanagement has recently become the most popular approach for reconciling land claims and biodiversity conservation in South
Africa and beyond. Following the resolution of land claims on protected areas in South Africa, comanagement arrangements have
been created between the relevant conservation authorities and the land claimant communities who are legally awarded tenure
rights to the land. However, it is doubtful that these partnerships constitute success for the former land claimants. Using
the case of a “resolved” land claim in Mkambati Nature Reserve, Eastern Cape Province, as well as insights from comanagement
literature, this paper identifies and discusses three key possible reasons for the unimpressive performance of comanagement
in reconciling land restitution and conservation. The first one is the origins of the comanagement idea in the conservation
of high value natural resources (e.g., fisheries, forestry), rather than in or including concerns for resource rights. The
second reason is the neglect of key conditions for successful comanagement, as discussed in the comanagement literature. The
final reason is the ambiguity in settlement agreements, including the use of terminology and concepts that reinforce unequal
power relationships, with the state emerging as the powerful partner. This paper concludes that, unless there is a serious
reassessment of the comanagement idea as a way of reconciling land reform and conservation, and a possible review of settlement
agreements that have relied on comanagement, both the integrity of the “successful land claimant’s rights” and that of conservation
remain under threat. 相似文献
12.
Benefits-based management seeks to provide recreation benefits for recreation participants by managing the physical environments
in which recreation occurs. This study investigates the relationship between benefits desired by visitors and the physical,
social, and managerial characteristics of settings that facilitate realization of recreation benefits. Data such as perceived
benefits from recreation experiences, setting attributes that significantly influenced perceived benefits, and sociodemographic
variables were collected from 376 visitors to Sorak-san National Park in the eastern part of the Korean peninsula. Cluster
analysis was used to group visitors' desired benefits into 12 domains: relationship with nature/scenery, escaping pressure,
learning about nature, family togetherness, introspection, exploration, autonomy/achievement, being with friends, leading
others, skills/learning, risk taking, and meeting/observing new people. Multiple regression was used to link benefit domains
with the characteristics of settings. The social attribute of recreation settings was linked to eight of the ten benefit domains.
There were two statistically strong multiple regression correlations: (1) between domain of “relationship with nature /scenery”
and the attributes “forest/water,”“attractive nature,” and “facility/maintenance” and (2) between the domain of “escaping
pressure” and the attributes “attractive nature” and “social.” The results of this study are useful to managers in their efforts
to provide recreation opportunities for visitors to achieve beneficial outcomes. 相似文献
13.
ABSTRACT: Economic values of riparian buffers in a watershed are evaluated by the changes in the net economic return for farming with and without riparian buffers when achieving the same water quality objectives. The simulated water quality impacts of alternative farming systems using SWAT and experimental data for riparian buffers are used in a mathematical optimization model to estimate net economic return for farming subject to a water quality objective. Physical characteristics such as stream length, channel slope, average land slope, cropland percentage and several soil attributes are identified in the watershed using ARC/INFO GIS. A regression model is then used to evaluate the impacts of these physical characteristics on the estimated economic values of buffers. The study is conducted in Goodwater Creek watershed, Missouri. The results show the estimated economic value of buffers is significantly affected by some soil properties, stream length, and cropland percentage in watershed and can be used to improve the effectiveness of riparian buffers at watershed and regional levels. 相似文献
14.
Kyle A. Young 《Environmental management》2000,26(2):131-144
Oncorhynchus sp.), regional governments now restrict timber harvest in riparian forests. I summarize and assess the riparian zone management
guidelines of the states of California, Oregon, and Washington (USA) and the province of British Columbia (Canada). Only Oregon
and British Columbia protect fish-bearing streams with “no-harvest” zones, and only the wider (20–50 m) no-harvest zones for
larger fish-bearing streams in British Columbia are likely to maintain near-natural linkages between riparian and stream ecosystems.
All four jurisdictions protect most streams with “management zones” of variable width, in which timber harvest activities
are restricted. All the management zone guidelines permit the harvest of the largest conifers from riparian forests and will,
if applied over a series of timber harvest rotations (60–80 years), result in the continued removal of potential sources of
large woody debris from the region's watersheds. All four jurisdictions require additional protection for streams and watersheds
that are severely degraded or (in the United States) contain threatened or endangered species. The governments of the PNW
have taken a “manage until degraded, then protect” approach to riparian forest management that is unlikely to maintain or
restore the full suite of riparian-stream linkages necessary for lotic ecosystems to function naturally at the stream, watershed,
basin, or regional scale. 相似文献
15.
Conflicts over how to “scale” policy-making tasks have characterized environmental governance since time immemorial. They
are particularly evident in the area of water policy and raise important questions over the democratic legitimacy, economic
efficiency and effectiveness of allocating (or “scaling”) tasks to some administrative levels as opposed to others. This article
adopts a comparative federalism perspective to assess the “optimality” of scaling—either upward or downward—in one issue area,
namely coastal recreational water quality. It does so by comparing the scaling of recreational water quality tasks in the
European Union (EU) and Australia. It reveals that the two systems have adopted rather different approaches to scaling and
that this difference can partly be accounted for in federal theoretical terms. However, a much greater awareness of the inescapably
political nature of scaling processes is nonetheless required. Finally, some words of caution are offered with regard to transferring
policy lessons between these two jurisdictions. 相似文献
16.
Kenneth A. Barrick 《Environmental management》2010,45(1):192-202
Geyser basins provide high value recreation, scientific, economic and national heritage benefits. Geysers are globally rare,
in part, because development activities have quenched about 260 of the natural endowment. Today, more than half of the world’s
remaining geysers are located in Yellowstone National Park, northwest Wyoming, USA. However, the hydrothermal reservoirs that
supply Yellowstone’s geysers extend well beyond the Park borders, and onto two “Known Geothermal Resource Areas”—Island Park
to the west and Corwin Springs on the north. Geysers are sensitive geologic features that are easily quenched by nearby geothermal
wells. Therefore, the potential for geothermal energy development adjacent to Yellowstone poses a threat to the sustainability
of about 500 geysers and 10,000 hydrothermal features. The purpose here is to propose that Yellowstone be protected by a “Geyser
Protection Area” (GPA) extending in a 120-km radius from Old Faithful Geyser. The GPA concept would prohibit geothermal and
large-scale groundwater wells, and thereby protect the water and heat supply of the hydrothermal reservoirs that support Yellowstone’s
geyser basins and important hot springs. Proactive federal leadership, including buyouts of private groundwater development
rights, can assist in navigating the GPA through the greater Yellowstone area’s “wicked” public policy environment. Moreover,
the potential impacts on geyser basins from intrusive research sampling techniques are considered in order to facilitate the
updating of national park research regulations to a precautionary standard. The GPA model can provide the basis for protecting
the world’s few remaining geyser basins. 相似文献
17.
This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental
conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic
noise (road, rail, and air), NO2, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only
exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally,
we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis
on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known
as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all
local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental
outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO2 are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental
“bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental
outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental
“goods” than lower-income groups. 相似文献
18.
Improvements on Flood Alleviation in Germany: Lessons Learned from the Elbe Flood in August 2002 总被引:1,自引:0,他引:1
The increase in damage due to natural disasters is directly related to the number of people who live and work in hazardous
areas and continuously accumulate assets. Therefore, land use planning authorities have to manage effectively the establishment
and development of settlements in flood-prone areas in order to avoid the further increase of vulnerable assets. Germany faced
major destruction during the flood in August 2002 in the Elbe and Danube catchments, and many changes have been suggested
in the existing German water and planning regulations. This article presents some findings of a “Lessons Learned” study that
was carried out in the aftermath of the flood and discusses the following topics: 1) the establishment of comprehensive hazard
maps and flood protection concepts, 2) the harmonization of regulations of flood protection at the federal level, 3) the communication
of the flood hazard and awareness strategies, and 4) how damage potential can be minimized through measures of area precaution
such as resettlement and risk-adapted land use. Although attempts towards a coordinated and harmonized creation of flood hazard
maps and concepts have been made, there is still no uniform strategy at all planning levels and for all states (Lae
nder) of the Federal Republic of Germany. The development and communication of possible mitigation strategies for “unthinkable
extreme events” beyond the common safety level of a 100-year flood are needed. In order to establish a sustainable and integrated
flood risk management, interdisciplinary and catchment-based approaches are needed. 相似文献
19.
Theodore A. Endreny Eric F. Wood 《Journal of the American Water Resources Association》2003,39(1):165-181
ABSTRACT: The Export Coefficient model (ECM) is capable of generating reasonable estimates of annual phosphorous loading simply from a watershed's land cover data and export coefficient values (ECVs). In its current form, the ECM assumes that ECVs are homogeneous within each land cover type, yet basic nutrient runoff and hydrological theory suggests that runoff rates have spatial patterns controlled by loading and filtering along the flow paths from the upslope contributing area and downslope dispersal area. Using a geographic information system (GIS) raster, or pixel, modeling format, these contributing area and dispersal area (CADA) controls were derived from the perspective of each individual watershed pixel to weight the otherwise homogeneous ECVs for phosphorous. Although the CADA‐ECM predicts export coefficient spatial variation for a single land use type, the lumped basin load is unaffected by weighting. After CADA weighting, a map of the new ECVs addressed the three fundamental criteria for targeting critical pollutant loading areas: (1) the presence of the pollutant, (2) the likelihood for runoff to carry the pollutant offsite, and (3) the likelihood that buffers will trap nutrients prior to their runoff into the receiving water body. These spatially distributed maps of the most important pollutant management areas were used within New York's West Branch Delaware River watershed to demonstrate how the CADA‐ECM could be applied in targeting phosphorous critical loading areas. 相似文献
20.
During the post-World War II era, the Mojave Desert Region of San Bernardino County, California, has experienced rapid levels
of population growth. Over the past several decades, growth has accelerated, accompanied by significant shifts in ethnic composition,
most notably from predominantly White non-Hispanic to Hispanic. This study explores the impacts of changing ethnicity on future
development and the loss of open space by modeling ethnic propensities regarding family size and settlement preferences reflected
by U.S. Census Bureau data. Demographic trends and land conversion data were obtained for seven Mojave Desert communities
for the period between 1990 and 2001. Using a spatially explicit, logistic regression-based urban growth model, these data
and trends were used to project community-specific future growth patterns from 2000 to 2020 under three future settlement
scenarios: (1) an “historic” scenario reported in earlier research that uses a Mojave-wide average settlement density of 3.76
persons/ha; (2) an “existing” scenario based on community-specific settlement densities as of 2001; and (3) a “demographic
futures” scenario based on community-specific settlement densities that explicitly model the Region’s changing ethnicity.
Results found that under the demographic futures scenario, by 2020 roughly 53% of within-community open space would remain,
under the existing scenario only 40% would remain, and under the historic scenario model the communities would have what amounts
to a deficit of open space. Differences in the loss of open space across the scenarios demonstrate the importance of considering
demographic trends that are reflective of the residential needs and preferences of projected future populations. 相似文献