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1.
Wetland management: an analysis of past practice and recent policy changes in Ontario 总被引:2,自引:0,他引:2
Schulte-Hostedde B Walters D Powell C Shrubsole D 《Journal of environmental management》2007,82(1):83-94
The Ontario Government has recently released its latest Provincial Policy Statement (PPS), which includes a policy concerning wetland protection. This paper uses interviews with key respondents and the results of three separate case studies that examined the former PPS in order to assess the ability of the new policy to improve wetland conservation efforts in Ontario. The case studies include wetland conservation and urban stormwater management in the City of London for the periods 1978-1999 and 1978-2000, respectively. As well, agricultural drainage that occurred in the Township of Zorra for the period 1978-1997 is used to address this management dimension. While progress is evident, the current policy will be difficult to implement effectively because it inadequately deals with the fundamental aspects of management: fragmented jurisdiction, interagency communication, financial arrangements, enforcement, and promoting informed decision making. 相似文献
2.
Prosper F. Bangwayo‐Skeete Mintewab Bezabih Precious Zikhali 《Natural resources forum》2012,36(4):263-273
This paper uses data from the Central Highlands of Ethiopia to assess the productivity and production risk impacts of crop diversification. Using count index as a measure of crop biodiversity, results show that increasing crop biodiversity contributes positively to farm level productivity. In addition, the findings suggest that the level of production risk significantly responds to the level of diversity, with the effect highly conditional on the skewness. The major contribution of the paper is that, unlike previous similar studies that tended to focus on intra‐crop diversity, it incorporates the mutual interdependencies across crops within a farm by focusing on inter‐crop diversity. Hence the study adds to the growing empirical literature, particularly in Africa, that tests empirical relationships between productivity, risk and crop diversity. An important policy implication for a diversity rich country such as Ethiopia is that agro‐biodiversity can be used to improve agricultural productivity while promoting in situ conservation. 相似文献
3.
Past experience shows that inappropriate agricultural development in wetlands can undermine sustainability and may have profound social and economic repercussions for people dependent on the range of ecosystem services provided by those wetlands. Nonetheless, there is escalating pressure to expand agriculture within wetlands due to increasing population, in conjunction with efforts to increase food security. This paper describes the development of a semi-analytical framework for identifying, organizing and analyzing the complex factors that link people, agriculture and wetland ecosystems — an index of Working Wetland Potential (WWP). The method is based on a form of multi-criteria analysis that integrates biophysical and socio-economic aspects of wetland utilization. The WWP index emerges from the aggregation of two values: the first arising from an appraisal of both the biophysical and socio-economic suitability of using the wetland for agriculture; and the second resulting from an assessment of the possible hazards, in relation to both social welfare and the ecological character of the wetland. Hence, the approach provides a way to explicitly integrate biophysical and social aspects of wetland utilization in a single index to enable an initial assessment of the suitability of using a wetland for agriculture. Results from three contrasting wetlands in sub-Saharan Africa are presented. 相似文献
4.
Barry Haack 《Environmental management》1996,20(3):411-419
Environmental managers need current, accurate information upon which to base decisions. Viable information, especially in developing countries, is often unavailable. Satellite remote sensing is an appropriate and effective data source for mapping the surface of the earth, including a variety of environmental features. Remote-sensing-derived information is enhanced by being one component within a geographic information system (GIS). These techniques were employed to study an expanding delta in East Africa.The Omo River flows from the Ethiopian Highlands into the northern end of Lake Turkana, creating a large delta extending between Ethiopia and Kenya. This isolated and unique wetland feature has expanded by over 500 sq km in the last 15 years as measured by space-borne remote sensing techniques and corroborated by low-altitude aircraft reconnaissance flights.The growth of the delta appears to be a function of both increased sedimentation and decreased lake levels and river flows. Within the delta there has been a selective decline in wildlife and an increase in human activity, both pastoral and agricultural. The uniqueness of this isolated delta suggests that consideration be given to its possible protection and management.On leave from Department of Geography, George Mason University, Fairfax, Virginia 22030, USA 相似文献
5.
Global environmental crisis narratives about biodiversity loss promote conservation research on how human activities impact natural resources and link scientific findings to protectionist policies. This paper critiques how local knowledge, over space and through time, is constructed for these studies and integrated with ecological measures and qualitative interpretations of biodiversity conditions. As a case example, we describe how ethnoecological research at Mt. Kasigau, a biodiversity hot spot in Southeastern Kenya, changes ‘scientific’ views on human–resource relations. Species richness in woody plants and local knowledge about trees show resource continua on the mountain that question the designation of diverse undisturbed forests and degraded human‐utilized lands. Local narratives document spatially dynamic and adaptive relationships between the Kasigau Taita and their plant resources as they moved up and down the mountain in response to environmental conditions and extra local forces. We argue that greater ‘local learning’ about local places is important to hypothesizing and potentially guiding ‘global action’ for biodiversity conservation. 相似文献
6.
The extent and causes of changes in the fresh-water wetlands of South Kingstown, Rhode Island were determined through field work and through the analysis of panchromatic aerial photographs taken in 1939 and 1972. During this period, there was a net loss of 0.9 percent of the total area (2345.2 ha) of wetland present in 1939. Highway construction and residential development accounted for most of this loss. Approximately 17 percent of the wetland present in 1939 had changed sufficiently by 1972 to warrant reclassification. Plant succession alone accounted for 57 percent of the changes in wetland types, while man's activities were influential in 41 percent of the cases. Ninety-two percent of the natural changes in wetland types was progressive, while 58 percent of the changes induced by man and undetermined causes was retrogressive. Man's major role was to alter the water regimes and vegetation of wetlands. There was a decrease in wetland diversity as the most abundant type, wooded swamp, grew in area while the abundance of shallow marshes, meadows, and shrub swamps declined. A knowledge of wetland dynamics is essential in the management of wetlands for a diversity of wildlife and other natural values. 相似文献
7.
The present US Federal wetland management strategy under Section 404 of the Clean Water Act does not account for the differences in the natural values of wetlands and their different vulnerability to development pressure. The strategy, aimed at reducing the regulatory burden, provides for different levels of wetland protection, primarily by designating certain activities in or affecting wetlands as essentially harmless, having only minor impacts even when considered for their cumulative effects. Such activities are authorized under general permits precluding any evaluation of project impacts. A sounder, yet practical, rationale for wetland management and regulatory relief should be linked to the scarcity of certain wetland habitats, the habitat diversity or carrying capacity, the degree of degradation from past development, and the incremental losses already incurred within the same wetland ecosystem. The regulatory effort should be concentrated where these characteristics indicate high-value wetlands.Wetland impacts appear to fit into five basic orders of magnitude; these pertain to the relative cost and difficulty of impact mitigation. Up to 13 ecological and public-interest variables can modify the seriousness of the basic impact. Together, the basic orders of impact and modifying variables describe the theoretical framework for wetland management. However, a practical rationale for better wetland management must be constrained to factors not requiring a field investigation in advance of project planning for construction and development.This article was produced in part from work funded by the Office of Technology Assessment (OTA) of the United States Congress for use in its study, Wetlands: Their Use and Regulation. The views expressed do not necessarily represent those of OTA. 相似文献
8.
This paper explains briefly the conceptual framework of an ecosystem-based multiple-use forest management planning focusing on biodiversity conservation and participation. Some results from a case study were documented to realize the implementation of the concept. A strong liaison between the related institutions and major stakeholders and the effective use of Geographic Information System (GIS) and Remote Sensing (RS) are necessary. Effective participation is evident only with the involvement of enthusiastic and skillful stakeholders. A case study of ??neada, Turkey, supported the idea that participation as communication has better possibilities to promote multiple-use forest management than participation as information gathering. Primary challenges relate to the effectiveness of conservation program, availability of coherent biodiversity data, capacity building; awareness, training, and common understanding of biodiversity and protected area concept; coordination among the related institutions and stakeholders; and willingness and enthusiasm of authorities to accept and implement the concept. 相似文献
9.
Ted L. Ernst Nancy C. Leibowitz Denis Roose Steve Stehman N. Scott Urquhart 《Environmental management》1995,19(1):99-113
The United States Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) will monitor the
nation's resources by evaluating the status and trends of selected indicators of condition using a probability-based sampling
design. The EMAP-Wetlands program will monitor the condition of the nation's wetlands. The EMAP classification system is an
aggregation of the many subclasses of the US Fish and Wildlife Service's National Wetlands Inventory (NWI) classification
system. This aggregation results in fewer wetland classes with more wetlands per class than the NWI system. Aggregation of
the NWI classification was based primarily on dominant vegetation cover, flooding regimes, dominant water source, and adjacency
to rivers and lakes. We evaluated the EMAP classification system and sampling design using NWI digital wetlands data for portions
of Illinois, Washington, North Dakota, and South Dakata. Relative numbers of wetlands, total areas, average areas, and common
versus rare classes were compared between the EMAP and NWI classification systems. As expected, the EMAP classification provided
fewer wetland polygons, each with larger areas, without altering total wetland area. Summary statistics comparing sample estimates
to true population parameters (represented by the NWI data) demonstrated the effectiveness of the EMAP sampling design with
the exception of rare EMAP classes in the selected regions. Although simple random sampling is inadequate for both large and
small wetlands, the EMAP sampling design is readily adapted to provide better estimates for these categories. Aggregating
the NWI classification to the EMAP classification provides fewer wetland classes, with more wetlands per class, for EMAP's
annual reports and statistical summaries.
The research in this report has been funded by the United States Environmental Protection Agency (EPA) under contracts 68-C8-0006
to ManTech Environmental Technology, Inc. and 68-03-3532 to The Bionetics Corporation. Mention of trade names does not constitute
endorsement or recommendation for use. 相似文献
10.
Agricultural drainage and wetland management in Ontario 总被引:2,自引:0,他引:2
Land drainage is recognized as an integral part of agricultural activity throughout the world. However, the increase in agricultural production has resulted in the loss of wetland functions and values. Therefore, wetland management and agricultural drainage illustrate the conflict between economic development and natural values. This research assesses the approval process for agricultural land drainage in Ontario, Canada, to determine how the benefits of increased agricultural production are balanced against the loss of wetland values. A permit review of drainage applications was conducted from 1978 to 1997 in Zorra Township, Ontario, Canada. Data collection also included the document reviews, interviews with government agencies and wetland evaluation files. The selected criteria include efficiency, equity, consistency and adequacy. The results indicate that while the process is efficient, fundamental problems remain with the bargaining process. 相似文献
11.
As inland wetlands face increasing pressure for development, both the federal government and individual states have begun reevaluating their respective wetland regulatory schemes. This article focuses first on the effectiveness of the past, present, and proposed federal regulations, most notably the Section 404, Dredge and Fill Permit Program, in dealing with shrinking wetland resources. The article then addresses the status of state involvement in this largely federal area, as well as state preparedness to assume primacy should federal priorities change. Finally, the subject of comprehensive legislation for wetland protection is investigated, and the article concludes with some procedural suggestions for developing a model law. 相似文献
12.
Adapting to climate variability: Pumpkins, people and policy 总被引:2,自引:0,他引:2
Understanding of how best to support those most vulnerable to climate stress is imperative given expected changes in climate variability. This paper investigates local adaptation strategies to climate variability, focusing on agricultural decision‐making in a communal irrigation scheme in Vhembe District, Limpopo Province, South Africa. Research done through interviews, surveys and participatory methods demonstrates that adaptation strategies within a community are socially differentiated and present differing objectives and priorities. These results highlight the need for intervention and policy that support a heterogeneous response to a wide range of stresses. Evidence for climate change is clear and the need for adaptation is urgent. However, adaptation measures have to be sensitively integrated with ongoing development pathways to ensure they are sustainable and relevant to local priorities. 相似文献
13.
There is a general lack of understanding of wetland processes and a general paucity of scientific research to predict the
effects of development on wetland boundary. This paper presents the results of a survey of wetland managers as to how they
delineate wetland boundaries, define compatible land uses, and restrict land uses adjacent to wetland boundaries. A major
finding from the survey is that 75% of land-use planners and wetland managers failed to identify any compatible land use or
restricted land use for development proposals that may affect provincially significant wetlands. The government agencies overwhelmingly
lack adequate methodologies and/or criteria to delineate and protect wetland boundaries. The paper closes with a plea to consider
dynamic hydrological factors in land-use planning. 相似文献
14.
Kidane-Mariam T 《Environmental management》2003,31(3):0313-0327
This article examines the environment and habitat management experiences of Ethiopia and Ghana in the postindependence period
(1960–2000). Based on extensive archival research, semistructured focused interviews of environment and habitat officers of
the World Bank, the United Nations System and the International Union for the Conservation of Nature (IUCN) and personal professional
field experiences, the paper argues that the uncritical adoption of externally generated discourses, narratives, policy guidelines,
and strategies of environmental and habitat management has structured thought and action in both countries. The experience
of both countries in defining and responding to environmental and human settlement management is explored from a political
ecology perspective. The analysis indicates that both countries have essentially adopted a technocratic, state-centered, and
unsustainable management strategy framework based on population control, poverty reduction, sustainable development, and capacity-building.
It also suggests that international organizations such as the World Bank, INCN, and the United Nations system have been important
sources of thought and action in both countries. Conversely, regional international organizations such as the Economic Commission
for Africa, the Organization of African Unity and the African Development Bank have largely served as conduits for the diffusion
of global discourses, narratives, policies and strategies. The need for adopting management policies and strategies that are
based on principles of multiple engagement, decentralization, incentives, public education, and participation is underscored. 相似文献
15.
Restoration of a Canadian Prairie Wetland with Agricultural and Municipal Wastewater 总被引:1,自引:0,他引:1
3 /day (800,000 US gallons) of municipal wastewater and beef processing wastewater. A large nongovernmental organization hastened
restoration with a development process that outlined restoration goals and management objectives to satisfy a dual mandate
of wastewater treatment and wildlife habitat creation. In 1995, after five years of wastewater additions, the basins had been
refilled and the surrounding uplands had been acquired and restored. The Frank Lake Conservation Area currently provides high-quality
habitat for a variety of wildlife in a region where many of the native plants and animals species have been lost due to habitat
loss and fragmentation. The success of upland and water management strategies is reflected in the increase of target species'
abundance and richness: 50 shorebird species, 44 waterfowl species, 15 raptor species, and 28 other new bird species have
returned to the marsh since restoration. As well, significant N and P reduction occurs as waters flow through the first basin
of the marsh. The management strategies of this project that satisfied a dual mandate serve as a model to guide managers of
other large-scale wetland restoration projects. 相似文献
16.
Snoussi M Kitheka J Shaghude Y Kane A Arthurton R Le Tissier M Virji H 《Environmental management》2007,39(5):587-600
Anthropogenic factors associated with damming and water abstraction, and the resultant environmental pressures, are reviewed
in six African river catchments using records and forecasts of climatic, demographic, and land-use change. Changes in the
states of the flow regime through catchment drainage systems to the coastal sea are considered in conjunction with climate
change and other human-induced pressures. The impacts of these changes on downstream and coastal environments and their communities
are described in past, present, and future perspectives. Linkages between the issues and the pressures of damming and water
abstraction are appraised and scientific, policy, and management responses proposed aimed at remedying existing and perceived
future negative impacts. The study proposes that there is a need to integrate catchment and coastal management to account
for the whole water flow regime together with its human dimensions. Management priorities relating to the operation of existing
damming and abstraction schemes and planning of future schemes include the following: consideration of ways in which water
discharges could be adjusted to provide improvements in downstream and coastal environmental and socioeconomic conditions;
addressing the problem of sediment trapping impacting on the sustainability of dam reservoirs; and assessment of downstream
and coastal impacts of future schemes in the light of climate change forecasts. 相似文献
17.
18.
Wise Use of Wetlands: Current State of Protection and Utilization of Chinese Wetlands and Recommendations for Improvement 总被引:2,自引:0,他引:2
Wetland protection and utilization sometimes appear to be in conflict, but promoting the wise use of wetlands can solve this
problem. All countries face the challenge of sustainable development of wetlands to a greater or lesser extent, but the problem
is especially urgent in developing countries, such as China, that want to accelerate their economic development without excessive
environmental cost. Chinese wetlands contribute greatly to economic development, but improper use of these natural resources
has endangered their existence. It is thus necessary to provide scientific guidance to managers and users of wetlands. In
this paper, we analyze the present status of Chinese wetland protection and utilization, and discuss problems in six categories:
a lack of public awareness of the need for wetland protection; insufficient funding for wetland protection and management;
an imperfect legal system to protect wetlands; insufficient wetland research; lack of coordination among agencies and unclear
responsibilities; and undeveloped technologies related to wetland use and protection. The wise use of Chinese wetlands will
require improvements in four main areas: increased wetland utilization research, scientific management of wetland utilization,
improved laws and regulations to protect wetlands, and wider dissemination of wetland knowledge. Based on these categories,
we propose a framework for the optimization of wetland use by industry to provide guidance for China and other countries that
cannot sacrifice economic benefits to protect their wetlands. 相似文献
19.
Mapping wetlands in the Lower Mekong Basin for wetland resource and conservation management using Landsat ETM images and field survey data 总被引:1,自引:0,他引:1
The Mekong River Basin is considered to be the second most species rich river basin in the world. The 795,000 km(2) catchment encompasses several ecoregions, incorporating biodiverse and productive wetland systems. Eighty percent of the rapidly expanding population of the Lower Mekong Basin (LMB), made up in part by Lao PDR, Thailand, Cambodia and Viet Nam, live in rural areas and are heavily reliant on wetland resources. As the populations of Cambodia and Lao PDR will double in the next 20 years, pressure on natural resources and particularly wetlands can only increase. For development planning, resource and conservation management to incorporate wetland issues, information on the distribution and character of Mekong wetlands is essential. The existing but outdated wetland maps were compiled from secondary landuse-landcover data, have limited coverage, poor thematic accuracy and no meta-data. Therefore the Mekong River Commission (MRC) undertook to produce new wetland coverage for the LMB. As resources, funding and regional capacity are limited, it was determined that the method applied should use existing facilities, be easily adaptable, and replicable locally. For the product to be useful it must be accepted by local governments and decision makers. The results must be of acceptable accuracy (>75%) and the methodology should be relatively understandable to non-experts. In the first stage of this exercise, field survey was conducted at five pilot sites covering a range of typical wetland habitats (MRC wetland classification) to supply data for a supervised classification of Landsat ETM images from the existing MRC archive. Images were analysed using ERDAS IMAGINE and applying Maximum Likelihood Classification. Field data were reserved to apply formal accuracy assessment to the final wetland habitat maps, with resulting accuracy ranging from 77 to 94%. The maps produced are now in use at a Provincial and National level in three countries for resource and conservation planning and management applications, including designation of a Ramsar wetland site of international importance. 相似文献
20.
We inventoried wetland impoundments in the Louisiana, USA, coastal zone from the late 1900s to 1985. Historically, impoundment
of wetlands for reclamation resulted in direct wetland loss after levees (dikes) failed and the impounded area was permanently
flooded, reverting not to wetland, but to open-water habitat. A current management approach is to surround wetlands by levees
and water control structures, a practice termed semi-impoundment marsh management. The purpose of this semi-impoundment is
to retard saltwater intrusion and reduce water level fluctuations in an attempt to reduce wetland loss, which is a serious
problem in coastal Louisiana. In order to quantify the total impounded area, we used historic data and high-altitude infrared
photography to map coastal impoundments. Our goal was to produce a documented inventory of wetlands intentionally impounded
by levees in the coastal zone of Louisiana in order to provide a benchmark for further research.
We inventoried 370,658 ha within the coastal zone that had been intentionally impounded before 1985. This area is equal to
about 30% of the total wetland area in the coastal zone. Of that total area, approximately 12% (43,000 ha) is no longer impounded
(i.e., failed impoundments; levees no longer exist or only remnants remain). Of the 328,000 ha still impounded, about 65%
(214,000 ha) is developed (agriculture, aquaculture, urban and industrial development, and contained spoil). The remaining
35% (114,000 ha) of impoundments are in an undeveloped state (wetland or openwater habitat). In December 1985, approximately
50% (78,000 ha) of the undeveloped and failed impoundments were open-water habitat. This inventory will allow researchers
to monitor future change in land-water ratios that occur within impounded wetlands and thus to assess the utility of coastal
wetland management using impoundments. 相似文献