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1.
This article presents the results of a three-year effort at applying information technology to the problem of collaborative natural resource management in San Diego Bay. As such, it represents an approach to integrated coastal zone management (ICZM). This effort resulted from a collaboration between the San Diego Supercomputer Center at the University of California, San Diego and the San Diego Bay Interagency Water Quality Panel for the purpose of (1) developing an environmental data repository to facilitate the acquisition and sharing of data and (2) the development of a visual model of the bay in support of the development of a comprehensive, coordinated management plan for San Diego Bay. It was determined from this study that information technology is an important and key component to ICZM but that sociopolitical factors may override the benefits of decision-support systems and should be considered at the outset of any project of this kind.  相似文献   

2.
California has a forty-year history of successful coastal zone management. The San Francisco Bay Conservation and Development Commission, the California Coastal Commission, and the State Coastal Conservancy have protected and made accessible hundreds of miles of shoreline. While each agency has played a critical role, this article focuses on the Coastal Commission. Implementing the California Coastal Act, the Coastal Commission has partnered with local government, other agencies, nongovernmental organizations (NGOs), and the public to concentrate new development in already developed areas, and much of the rural coastal zone looks as it did in 1972. The Commission has protected and expanded public shoreline access through its regulatory actions. Using strong ecological science the Commission has protected a wide variety of sensitive habitats and wetlands. And under the authority of the Coastal Zone Management Act, the Commission has reviewed thousands of federal projects to assure that they are consistent with the Coastal Act. Challenges continue, though, including population growth, sea-level rise, and inadequate funding to update local coastal land use plans to address new issues, such as climate change adaptation. New investment is needed at the national, state, and local level to continue the success of the California program.  相似文献   

3.
Abstract

Although the early efforts to save San Francisco Bay in the 1960's provided the role model for protection of California's 1100 mile ocean coastline, neither Proposition 20 of 1972 nor the California Coastal Act of 1976 provided any benefits to San Francisco Bay. One result is that the Bay is locked into its urban, shoreline‐use dominated plan of 1969 while every other estuary and coastal wetland in California receives much stronger protection of its resources. Furthermore, due to the complexity of California's water laws, there is no instream flow protection for receiving waters such as San Francisco Bay. This is particularly critical considering that 70% of the Bay's freshwater inflow has been diverted. The Bay's present decline as the largest and most important estuary on the West Coast, as well as its possible death as an estuary, may be irreversible. The problem requires the immediate attention of engineering, scientific, economic and legal disciplines if San Francisco Bay is to be saved.  相似文献   

4.
Abstract

The San Diego Coast Regional Commission, faced with the responsibility of approving, approving with conditions, or denying permits for development proposed along the scenic coastal bluffs of San Diego county, has adopted guidelines for bluff‐top development which assures retention of scenic vistas and provision of public access while permitting private landowners “reasonable use”; of their property. These unique guidelines delineate certain environmental and aesthetic parameters within which bluff‐top development may take place. Portions of the guidelines are presented, and some of the factors leading to their formulation and adoption are discussed.  相似文献   

5.
Abstract

Competent administration of the Coastal Zone Management Act of 1972 (CZMA) must proceed on an informed understanding of the organization styles and capacities of agencies presently dealing with similar problems. One such agency, the San Francisco Bay Conservation and Development Commission (BCDC), the forerunner of the California model of coastal management, is analyzed here to shed light on where we are headed and what we can expect administratively as the CZMA becomes an operation reality.

The major administrative insights offered fall into the areas of: (1) effectiveness assessment‐the BCDC's success is systematically defined and measured, and a discussion of what effectiveness evaluation implies in the area of coastal resource management is undertaken; (2) understanding organizational success—the BCDC's administrative style is analyzed in terms of the synergy which has been created between its organizational structure and decision‐making process; and (3) implications of agency success—which of the BCDC's lessons are most valuable and how these can be applied to other situations are shown.  相似文献   

6.
Using CalCOFI data for coastal shallow stations (above 100 m depth), higher than expected nitrate concentrations were detected in near-surface high-temperature waters off of Central Baja California during some El Niño winters. Though recent data are not available for Central Baja California, past El Niño data, though limited, showed nitrate concentrations above 16 μM at temperatures above 16 °C, and nitrate concentrations between 1 and 2 μM at 19 °C, while the previously established relationship of temperature and nitrate for California Current waters predicts nitrate depletion above 14 or 15 °C. The anomalous, high temperature–high nitrate enrichment events documented in Central Baja California were detected as shallow as 9 m and as deep as 73 m, were associated with low-oxygen (between 2 and 4 ml/l) and high-salinity (between 33.8 and 34.3 psu) waters, and occurred during the winter months of an El Niño year. Using recent data for San Diego, CA, similar but weaker enrichment events were detected for the El Niño winter of 1997–1998. The periodic shoaling of a subsurface subtropical water mass of high temperature, high salinity, low oxygen and high nutrients during some El Niño winters is proposed to cause periodic enrichment and to maintain productivity during warming events in this area. Enrichment events were not detected off Ensenada, in Northern Baja California, possibly due to the amplification of the onshore flow during El Niño there, or due to the Ensenada front. The proposed mechanism of periodic enrichment of nutrient-depleted surface waters during some El Niño winters by subsurface waters from the California Undercurrent may explain the following: (1) survival of giant kelp forests at their southern limit in Central Baja California documented during past El Niño events in warm waters, (2) the rapid recovery and high carrying capacity of giant kelp documented after the mass disappearance during El Niño 1997–1998, and (3) the increase in the extent of mesotrophic chlorophyll detected in the area during the 1997–1998 and 1982–1983 El Niño events.  相似文献   

7.
Abstract

Policymakers and analysts concerned with coastal issues often need economic value information to evaluate policies that affect beach recreation. This paper presents economic values associated with beach recreation in San Diego County generated from a recreation demand model that explains a beach user's choice of which beach to visit. These include estimates of the economic values of a beach day, beach closures, and beach amenities.  相似文献   

8.
A pseudo-two-dimensional numerical model of estuarine phytoplankton growth and consumption, vertical turbulent mixing, and idealized cross-estuary transport was developed and applied to South San Francisco Bay. This estuary has two bathymetrically distinct habitat types (deep channel, shallow shoal) and associated differences in local net rates of phytoplankton growth and consumption, as well as differences in the water column's tendency to stratify. Because many physical and biological time scales relevant to algal population dynamics decrease with decreasing depth, process rates can be especially fast in the shallow water. We used the model to explore the potential significance of hydrodynamic connectivity between a channel and shoal and whether lateral transport can allow physical or biological processes (e.g. stratification, benthic grazing, light attenuation) in one sub-region to control phytoplankton biomass and bloom development in the adjacent sub-region. Model results for South San Francisco Bay suggest that lateral transport from a productive shoal can result in phytoplankton biomass accumulation in an adjacent deep, unproductive channel. The model further suggests that turbidity and benthic grazing in the shoal can control the occurrence of a bloom system-wide; whereas, turbidity, benthic grazing, and vertical density stratification in the channel are likely to only control local bloom occurrence or modify system-wide bloom magnitude. Measurements from a related field program are generally consistent with model-derived conclusions.  相似文献   

9.
Abstract

With the future of the Coastal Energy Impact Program (CEIP) in question and with oil and gas leasing and drilling activities in the Gulf of Mexico expected to increase, the question arises as to how energy impacts are to be mitigated. It is concluded that CEIP has helped to mitigate coastal energy impacts. If it is left unfunded, an alternative would be to provide Outer Continental Shelf (OCS) royalties to states to be used for impact prevention and mitigation.  相似文献   

10.
Beach replenishment has been proposed to increase nesting habitat for horseshoe crabs, but its environmental consequences may compromise the egg development and viability of this declining species. Horseshoe crab habitat requirements were used to build a habitat suitability model in STELLA to predict the potential impacts of beach replenishment on horseshoe crab eggs. A habitat suitability index (H.S.I.) comprised of six variables (dissolved oxygen, sediment grain size, sand temperature, sand moisture, wave energy, and salinity) was developed and compared between replenished and natural beaches. Sediment grain size and dissolved oxygen were higher in the natural beach, whereas sand temperature and moisture were higher in the replenished beach, resulting in significantly higher suitability of the natural beach (p = 5.39 × 10?15, df = 30). The model was most sensitive to air temperature, rainfall, tide, and sediment grain size. This model is useful for understanding the processes affecting horseshoe crabs and predicting impacts of coastal management activities on habitat suitability. Based on the results of this model, beach replenishment is not recommended for increasing or improving horseshoe crab habitat, unless care is taken to match fill sediment to natural grain size and color.  相似文献   

11.
Two major environmental problems currently affecting the Louisiana coastal zone are a high rate of wetland loss and high levels of surface water pollution. The application of secondarily treated wastewater to wetlands can be a means of dealing with both of these problems. The benefits of wetland wastewater treatment include improved surface water quality, increased accretion rates to balance a high relative water level rise due mainly to subsidence, improved plant productivity and habitat quality, and decreased capital outlays for conventional engineering treatment systems. Wetland treatment systems can, therefore, be designed and operated to restore deteriorating wetlands. Hydrologically altered wetlands, which are common in the Louisiana coastal zone, are appropriate for receiving municipal and some types of industrial effluent. While the U.S. Environmental Protection Agency has determined wetland wastewater treatment is effective in treating municipal effluent, it has discouraged the use of natural wetlands for this purpose. At the same time, funds are being used for the construction of artificial wetlands to treat municipal effluent. In the Louisiana coastal zone, however, wetlands are deteriorating and disappearing due to hydrological alteration and a high rate of relative sea level rise. If no action is taken, these trends will continue. Effluent discharge to existing wetlands should be incorporated into a comprehensive management plan designed to increase sediment and nutrient input into subsiding wetlands in the Louisiana coastal zone, improve water quality, and result in more economical waste‐water treatment. The authors believe that the Louisiana example serves as a model for other coastal areas especially in light of projections of accelerated sea level rise.  相似文献   

12.
Shipping traffic poses a worldwide threat to many large whale species. Spatially explicit risk assessments are increasingly being used as a tool to minimize ship-strike risk. These assessments often use static representations of shipping patterns. We used Automatic Identification System data to quantify variability in cargo shipping traffic entering and exiting San Francisco Bay, which contains some of the busiest ports in the United States, at three temporal resolutions: (1) before and after implementation of the California Air Resources Board's Ocean-Going Vessels Fuel Rule, (2) among seasons, and (3) day versus night. We used the nonparametric Mood's Median test to compare median daily distance traveled because the data were not normally distributed and the variance was not homogeneous. Our analyses show that shipping traffic off San Francisco is dynamic at both interannual and daily temporal resolutions, but that traffic was fairly consistent among the seasons considered. Our analyses emphasize the importance of economic and regulatory drivers on interannual shipping traffic patterns. Shipping traffic is expected to continue to change off the U.S. West Coast and to increase globally. These changes in shipping traffic could have implications for the risk of ships striking whales and should be included in risk assessments.  相似文献   

13.
The Bay of La Paz, a coastal and shallow basin of the Gulf of California (depth<420 m), exchanges mixed-layer waters with the Gulf of California predominantly through Boca Grande (Big Mouth), in the northeastern part of the bay. Equatorial Surface Water (ESW) flows from the gulf to the bay; once there, due to evaporation processes, this water increases its salinity above 35.00, therefore becoming Gulf of California Water (GCW) Mass. During June 1998, the baroclinic circulation in the bay was dominated by a cyclonic gyre. The hydrographic dome, related to this gyre, is depicted until approximately 150-m depth. However, the vertical mixing of water between the mixed-layer and the ones below practically does not occur because of the development of a sharp pycnocline. This fact and the isolation of the bottom of the bay by a bathymetric sill (approximately 250-m depth) at Boca Grande induce low oxygen content, particularly in the bottom-waters (O2<0.1 ml/l). Chlorophyll values are higher and with larger vertical fluctuations within the Bay of La Paz than outside.  相似文献   

14.
Consistent with the policies set forth in the Coastal Zone Management Act, the California Coastal Act seeks to balance the utilization and conservation of coastal resources, taking into account the social and economic needs of the citizens of California. One way the statute pursues this balance is through its provisions for ports. These provisions have functioned as a type of smart growth planning for ports, encouraging densification of existing port districts and possibly averting maritime commercial and industrial sprawl along the California coast. One unintended consequence of the encouraged consolidation of port activities, when combined with the rapid growth in international trade over the last four decades, has been disproportionally large environmental and health impacts on low-income and minority communities surrounding ports. This article examines how the Port of Long Beach's conformance with the California Coastal Act has resulted in ongoing environmental justice concerns. It discusses approaches employed by the Port of Long Beach to reduce environmental justice concerns resulting from significant and unavoidable environmental impacts and offers suggestions for how to address this issue.  相似文献   

15.
Although coastal tourism is often looked to as a way of generating foreign revenue, it can also engender a range of social and environmental impacts. From an historical perspective, this article examines the growth of Cancún in the Mexican state of Quintana Roo since the late 1960s. The article documents a range of socioeconomic and environmental impacts associated with the rise of coastal tourism, and suggests that centralized planning and the provision of physical and financial infrastructure does not prevent those impacts. The principal causes of these impacts are also described, including changes in land-usage, population, tourism markets, foreign market penetration and control, an emphasis on short-term economic gain, weak regulatory enforcement, and an overall lack of integration of coastal zone management.  相似文献   

16.
Coastal ecosystems such as mangroves, salt marshes, and seagrasses provide important ecosystem services, including nursery habitat for fish, shoreline protection, and the recently recognized service of carbon sequestration and storage. When these wetland ecosystems are degraded or destroyed, the carbon can be released to the atmosphere, where it adds to the concentration of greenhouses gases (GHGs) that contribute to climate change. Many federal statutes and policies specifically require that impacts on ecosystem services be considered in policy implementation. Yet, no federal statute, regulation, or policy accounts directly for the carbon held in coastal habitats. There are a number of federal statutes and policies for which coastal carbon ecosystem services could reasonably be added to environmental and ecosystem considerations already implemented. We look at a subset of these statutes and policies to illustrate how coastal carbon ecosystem services and values might affect the implementation and outcomes of such statutes generally. We identify key steps for the inclusion of the ecosystem services of coastal habitats into the implementation of existing federal policies without statutory changes; doing so would increase the degree to which these policies consider the full economic and ecological impacts of policy actions.  相似文献   

17.
Abstract

On April 27, 1981, the Department of the Interior (DOI) published the final notice of lease sale 53—the Santa Maria Basin off Central California. In the northern part of the basin are located 29 tracts (out of a total 111 offered) considered environmentally sensitive by many and politically explosive by all. As expected, the state of California sued the federal government and has twice prevailed. Consequently, the DOI appealed these earlier rulings to the Supreme Court and in January 1984 the Court ruled in favor of the DOI. This well publicized case (Watt v. California) represents a failure on the part of the Congress, the Reagan Administration, and the coastal states to reach an accord on the degree of state participation in the Outer Continental Shelf (OCS) development process. This article does not attempt to resolve this debate; rather, this paper presents the contrasting arguments in the U.S. government; and it illustrates how U.S. coastal policy is politicized and shaped from the national level.  相似文献   

18.
The “no net wetland loss” goal has not been met in urban coastal regions where conditions continue to exacerbate wetland losses. Under the Clean Water Act (Section 404) the U.S. Army Corps of Engineers and U. S. Environmental Protection Agency share responsibility for regulating placement of fill material in wetlands. The `no discharge of fill' rules threaten coastal wetlands with continuing losses due to effects of changing climate, including rising sea levels, higher storm surges, and flooding. Where inland migration is limited by development, or where sediment accretion rates are lower than the rate of sea level rise, urban wetlands will be lost unless marsh topography is elevated. We explored regulatory and design approaches in recent Hudson-Raritan Estuary (HRE), San Francisco Bay Estuary and coastal Louisiana restorations, including creation of new marshland using dredge material. Questions related to sea level rise, ecological position within the landscape, or potential effects of extreme storm events were not addressed in the HRE restoration designs; these concerns were taken into account in other regions. We suggest benefits of marsh `replenishment' should be acknowledged in Federal regulatory policy and that consistent policies supportive of low-lying coastal marsh preservation in all regions should be enacted.  相似文献   

19.
As noted often by the former California Coastal Commission Executive Director Peter Douglas, the history of how the California coast was saved is a great repository of untold stories. Although the Commission has had a dramatic and tangible impact on California's coastal geography, the public is largely unaware of many of its early accomplishments. This article begins to chronicle the rich stories of California's coastal legacy by telling the story of how the Commission utilized the Coastal Zone Management Act (CZMA) to prevent Southern Pacific Railroad from developing a seven-mile stretch of the Monterey Bay shoreline. In so doing, the Commission helped make possible the creation of the Monterey Peninsula Recreational Trail, a public bicycle and pedestrian path that has grown to sixteen miles in length and runs through the heart of John Steinbeck's world-famous Cannery Row. The controversy also was the subject of the first judicial challenge of a state's federal authority under the CZMA and precluded private commercial and residential development that would have dramatically altered the urban form of the Monterey Peninsula. It is important to tell the story as the Coastal Commission's role in this remarkable accomplishment has been almost completely overlooked.  相似文献   

20.
Coastal areas are among the most biologically rich regions in the world. They provide tremendous benefit to people through ecological services like pollution filtration, carbon sequestration, and storm protection. However, human activity has decreased the ability of ecosystems to provide these services, and in many coastal areas, restoration is not as effective as it could be. Limited success is largely attributed to vague goals and a lack of holistic, science-informed planning. Quantifying coastal habitat health can aid in setting better restoration goals and lead to greater restoration success. The Long Island Sound Study National Estuary Program conducted the first comprehensive look at coastal habitat health for the Long Island Sound Estuary. In this study we also reviewed landscape-scale habitat assessment progress within other coastal programs. Results can be applied to establish ecosystem health-oriented goals that improve habitat function and resilience across coastal areas.  相似文献   

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