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1.
Land-use suitability is the ability of a given type of land to support a defined use. GIS is known as a powerful tool for handling spatial data in land-use analysis. Application of this tool alone cannot overcome the lack of consistency in opinions given by experts when trying to assign relative importance to each of the several criteria considered in a suitability analysis. The combination of GIS and Multi-Criteria Decision Analysis (MCDA) is a powerful approach used to assess land suitability. To address this issue, the Analytical Hierarchy Process method is used in combination with the GIS tool. The aim of this study is to demonstrate how GIS tools and AHP model can be used for integrated coastal resource planning and management. Based on the information from final map/suitability map, we can define the best area. The findings indicate that the area 1 (2111 m) from class 3 is the most appropriate one because it has good facilities and wide open areas. This study indicates how the integrated tool is handled effectively in a land use suitability analysis for building hotels in the coastal areas of Terengganu in Malaysia. This research develops a framework for integrating GIS and AHP to incorporate the decision maker’s preferences on a range of factors in finding land areas suitable for coastal development.  相似文献   

2.
Encroachment of tall grasses and shrubs in coastal dunes has resulted in loss of vegetation heterogeneity. This is expected to have negative effects on animal diversity. To counteract encroachment and develop structural heterogeneity grazing is a widely used management practice. Here, we aim to functionally interpret changes in vegetation composition and configuration following grazing management on habitat suitability for sand lizards. Aerial photographs taken over a period of 16 years were used to quantify changes in vegetation composition. A GIS-based method was developed to calculate habitat suitability for sand lizards in a spatially explicit manner, encompassing differences in vegetation structure and patch size. From 1987 to 2003 dune vegetation shifted from small patches of moss and sand to larger patches covered by shrubs and grasses. Grazing management did not have any significant effect on the overall level of heterogeneity, measured as habitat suitability for sand lizards. However, on a more local scale highly suitable patches in 1987 were deteriorating whereas unsuitable patches became more suitable in 2003. This inversion results from a broad shift with shrubs being a limiting habitat element in 1987 to sandy patches being the limiting element in 2003. Future changes are believed to negatively impact sand lizards. The habitat suitability model has proven to be a useful tool to functionally interpret changes in coastal dune vegetation heterogeneity from an animal’s perspective. Further research should aim to include multiple species operating on different scale levels to fully capture the natural landscape dynamics.  相似文献   

3.
To improve the present national and local sustainable planning capability for the coastal zone a GI application for the Italian Coastal Susceptibility Assessment was planned within an institutional agreement between ENEA and the Land Defence Service of the Italian Ministry of Environment. Taking into account previous European actions a suitable methodology to assess, in a quantitative way, the susceptibility of beaches to be eroded has been set up. The methodology balances the coastline trend as evaluated for a defined time period with the present coastal areas morphology and land use, this in order to derive a value that expresses the evolutionary process in terms of probability of the loss of goods within the ‘Homogeneous Coastal Tracts’. The trend in the movement of the sea-land line has been used asgeo-indicator of a complex dynamic balance that refers both to marine and inland systems, and a vector GI application was built and locally applied in southern Italian coastal areas. The present shoreline position and some other information describing the intrinsic beach morphologies, and having significance for the coastal erosion hazard assessment, have been derived from the national 1∶10.000 ortho-images of the National Cartographic Reference System provided by the Italian Ministry of Environment. The illustrated GI application— CoSTAT—keeps the nominal scale of all data collected or produced. In this analysis the coastal dune presence is analysed as factor limiting coastal erosion susceptibility. Applying a matrix calculation a quantitative evaluation of erosion susceptibility degree was achieved and plans were made to develop new information for a suitable use of Italian coastal areas. The work describes the methodology, the conceptual frame-work and the results of a local application.  相似文献   

4.
Oxyhemocyanin (OxyHc), blood protein, glucose, acylglycerol (AG), and lactate of Litopenaeus vannamei juveniles were investigated. Statistical analyses were done on baseline values for each metabolite and on OxyHc from shrimp cultured in outdoor (20-m2 ponds) and indoor (90-l tanks). The values obtained were compared with blood metabolites reported in the literature for L. vannamei maintained under similar conditions. Normal distribution was only found for samples from indoor shrimp. The distribution values for blood metabolites from shrimp cultured in outdoor ponds and indoor tanks were right or left skewed. OxyHc, blood proteins, and glucose levels were higher in shrimp cultured in outdoor ponds than those observed in shrimp maintained in indoor tanks. These differences were attributed to availability of live food in outdoor culture ponds. The OxyHc/protein ratio showed that 60% of blood protein is OxyHc in outdoor-cultured shrimp and was lower than in indoor-cultured shrimp, and this ratio was lower than that found (97%) in indoor-cultured shrimp. The type of food was identified as a dominant factor affecting blood metabolites. AG in outdoor-cultured shrimp was significantly lower than that observed in indoor-maintained shrimp. Blood lactate concentration of shrimp was not affected by the culture conditions. The blood levels for protein, glucose, and lactate reported here are similar to those reported previously for other crustacean species, indicating that these can be used as a reference for evaluating the physiological status of L. vannamei. When we compared the OxyHc, blood protein, glucose, and lactate levels of L. vannamei juveniles with other crustacean species, we observed that crabs, lobsters (low-activity species), and closed-thelycum shrimp species (mean-activity species) had lower values in comparison to those observed in open-thelycum shrimp species, including L. vannamei juveniles. Possibly the blood metabolites and OxyHc could be reflecting the morphological and physiological adaptation of crustaceans, because these metabolites will depend on energetic demands.  相似文献   

5.
The Integrated Coastal Zone Management (ICZM) Protocol in the Mediterranean means the coastal zone can be better protected and problems can be targeted in a coordinated manner. This research developed a model to improve Integrated Coastal Management (ICM) implementation in the region. The methodology collected data from Mediterranean coastal zone experts via semi-structured interviews and a review of Mediterranean Coastal Foundation ICM Conferences in 2007, 2008 and 2009. Results identified issues and recommended solutions at various points in the policy process and these were used to propose a model for the implementation of ICM. Research demonstrated the need for non symbolic engagement with science especially during the ex-ante, interim and ex-post reports of implementation. Improved and considered horizontal governance and capacity building was highlighted as crucial. Findings also emphasised the importance of legislatively supported bottom-up policy implementation for the Mediterranean to help develop local coastal management ownership. Finally, the particular complexity of coastal policy in an administratively and culturally diverse region was identified as the main difficulty for successful implementation of coastal policies.  相似文献   

6.
When the distribution of species is limited by propagule supply, new populations may be initiated by seed addition, but identifying suitable sites for efficiently targeted seed addition remains a major challenge for restoration. In addition to the biotic or abiotic variables typically used in species distribution models, spatial isolation from conspecifics could help predict the suitability of unoccupied sites. Site suitability might be expected to increase with spatial isolation after other factors are accounted for, since isolation increases the chance that a site is unoccupied only because of propagule limitation. For two native annual forbs in Californian grasslands, we combined experimental seeding and niche modeling to ask whether suitability of unoccupied sites could be predicted by spatial variables (either distances from, or densities of, conspecific populations), either by themselves or in combination with niche models. We also asked whether experimental tests of these predictions held up not only in the short term (one year), but also in the longer term (three years). For Lasthenia californica, seed additions were only successful relatively near existing populations. For Lupinus nanus, seeding success was low and was positively related to the number of conspecifics within 1 km. For both species, a few previously unoccupied sites remained occupied three years after seeding, but this subset was not predictable based on either spatial or niche variables. Seed addition alone may be a limited means of native forb restoration if suitable unoccupied sites are either rare or unpredictable, or if they tend to be close to where the species already occurs.  相似文献   

7.
Abstract:  The projected rise in sea level is likely to increase the vulnerability of coastal zones in the Caribbean, which are already under pressure from a combination of anthropogenic activities and natural processes. One of the major effects will be a loss of beach habitat, which provides nesting sites for endangered sea turtles. To assess the potential impacts of sea-level rise on sea turtle nesting habitat, we used beach profile measurements of turtle nesting beaches on Bonaire, Netherlands Antilles, to develop elevation models of individual beaches in a geographic information system. These models were then used to quantify areas of beach vulnerable to three different scenarios of a rise in sea level. Physical characteristics of the beaches were also recorded and related to beach vulnerability, flooding, and nesting frequency. Beaches varied in physical characteristics and therefore in their vulnerability to flooding. Up to 32% of the total current beach area could be lost with a 0.5-m rise in sea level, with lower, narrower beaches being the most vulnerable. Vulnerability varied with land use adjacent to the beach. These predictions about loss of nesting habitat have important implications for turtle populations in the region.  相似文献   

8.
Many species are restricted to a marginal or suboptimal fraction of their historical range due to anthropogenic impacts, making it hard to interpret their ecological preferences from modern-day data alone. However, inferring past ecological states is limited by the availability of robust data and biases in historical archives, posing a challenge for policy makers . To highlight how historical records can be used to understand the ecological requirements of threatened species and inform conservation, we investigated sperm whale (Physeter macrocephalus) distribution in the Western Indian Ocean. We assessed differences in information content and habitat suitability predictions based on whale occurrence data from Yankee whaling logs (1792–1912) and from modern cetacean surveys (1995–2020). We built maximum entropy habitat suitability models containing static (bathymetry-derived) variables to compare models comprising historical-only and modern-only data. Using both historical and modern habitat suitability predictions  we assessed marine protected area (MPA) placement by contrasting suitability in- and outside MPAs. The historical model predicted high habitat suitability in shelf and coastal regions near continents and islands, whereas the modern model predicted a less coastal distribution with high habitat suitability more restricted to areas of steep topography. The proportion of high habitat suitability inside versus outside MPAs was higher when applying the historical predictions than the modern predictions, suggesting that different marine spatial planning optimums can be reached from either data sources. Moreover, differences in relative habitat suitability predictions between eras were consistent with the historical depletion of sperm whales from coastal regions, which were easily accessed and targeted by whalers, resulting in a modern distribution limited more to steep continental margins and remote oceanic ridges. The use of historical data can provide important new insights and, through cautious interpretation, inform conservation planning and policy, for example, by identifying refugee species and regions of anticipated population recovery.  相似文献   

9.
Vietnam’s coastal zone provides a diverse range of natural resources and favourable conditions for social and economic development. However, its coastal ecosystems are highly vulnerable, due to several natural coastal hazards, over-exploitation and other human activities. In spite of diverse interventions, Vietnam’s coastal zone continues to experience significant damage from floods, erosion and typhoons. These hazards are being intensified by climate change and associated rising sea levels. This paper assesses the potential vulnerability of Vietnam’s coast to climate change and discusses possible adaptation policies and plan to reduce the impacts. GIS analysis was used for the assessment of coastal vulnerability. Related literature was reviewed to develop detailed understanding of coastal adaptation to climate change. Adaptation policies and plans were appraised to identify potential coastal adaptation policies and plans that could be adapted by Vietnam. It was identified that vulnerability of the coastal zone of Vietnam could not be attributed only to climatic factors, but also to the physical condition of the coastline. Much of Vietnam’s coastline, particularly, areas around the Red River delta and the Mekong River have elevations below 1 m. These coastlines are largely developed and serve as economic centres of the country, which makes the coast more vulnerable to climate change and the rising sea level. The paper concluded that a non-structural approach (coastal buffer zones, building houses on stilts, storm warning systems, growing of flood-resistant crops and elevated storm shelters with medicine and food storage) could be used by Vietnam to adapt her low-lying coastline around the two deltas to climate change as this strategy enables vulnerable areas to be occupied for longer before eventual retreat. However, for these policies to be successful, it should be planned, implemented well in advance, monitored and evaluated over time.  相似文献   

10.
There are presently few tools available for estimating epidemic risks from forest pathogens, and hence informing pro-active disease management. In this study we demonstrated that a bioclimatic niche model can be used to examine questions of epidemic risk in temperate eucalypt plantations. The bioclimatic niche model, CLIMEX, was used to identify regional variation in climate suitability for Mycosphaerella leaf disease (MLD), a major cause of foliage damage in temperate eucalypt plantations around the world. Using historical observations of MLD damage, we were able to convert the relative score of climatic suitability generated by CLIMEX into a severity ranking ranging from low to high, providing for the first time a direct link between risk and impact, and allowing us to explore disease severity in a way meaningful to forest managers. We determined that the ‘Compare Years’ function in CLIMEX could be used for site-specific risk assessment to identify severity, frequency and seasonality of MLD epidemics. We explored appropriate scales of risk assessment for forest managers. Applying the CLIMEX model of MLD using a 0.25° or coarser grid size to areas of sharp topographic relief frequently misrepresented the risk posed by MLD, because considerable variation occurred between individual forest sites encompassed within a single grid cell. This highlighted the need for site-specific risk assessment to address many questions pertinent to managing risk in plantations.  相似文献   

11.
Heavy-metal concentrations were measured in sediments and tissues of Posidonia oceanica seagrass from south-eastern Sicily (Italy) in order to assess the degree of metal pollution in the coastal area. Seagrasses and sediments were collected at four sites along the south-eastern coast of Sicily. Flame atomic absorption spectrophotometry (FAAS) was used to measure concentrations of Cu, Zn, Cd and Pb. Standard statistical analyses were used to assess significant differences among the levels of the elements measured in different tissues and sediment and spatial distribution. The greatest values of potentially toxic metal concentrations were observed at the station near the industrial sites of Augusta and Priolo. Comparisons with the concentrations of the same metals in other sites of north and western Sicily and with data from surveys in other areas of the Mediterranean Sea are shown.  相似文献   

12.
Phenotypic sex in sea turtles is determined by nest incubation temperatures, with warmer temperatures producing females and cooler temperatures producing males. The common finding of highly skewed female-biased hatchling sex ratios in sea turtle populations could have serious repercussions for the long-term survival of these species and prompted us to examine the thermal profile of a relatively pristine hawksbill nesting beach in Guadeloupe, French West Indies. Data loggers placed at nest depth revealed that temperatures in the forested areas were significantly cooler than temperatures in the more open, deforested areas. Using these temperatures as a predictor of sex ratio, we were able to assess the relative contributions of the different beach zones to the primary sex ratio: significantly more males were likely to be produced in the forested areas. Coastal forests are therefore important male-producing areas for the hawksbill sea turtle, and this has urgent conservation implications. On Guadeloupe, as on many Caribbean islands, deforestation rates are high and show few signs of slowing, as there is continual pressure to develop beachfront areas. The destruction of coastal forest could have serious consequences both in terms of local nesting behavior and of regional demography through the effects on population sex ratios. Human alterations to nesting habitat in other reptile taxa have been shown to modify the thermal properties of nest sites in ways that can disrupt their ecology by allowing parasite transmission, increasing vulnerability to climate change, or rendering existing habitat unsuitable.  相似文献   

13.
We demonstrate a recently developed spatial interpolation methodology in a study of the chronic effects of air pollution on respiratory morbidity. Our study uses data from the Ontario Health Study, a large survey of households in Ontario conducted for the province by Statistics Canada. The interpolation procedure imputes unobserved vectors of air pollution concentrations for individual Public Health Units, from those observed at a few fixed air pollution monitoring sites. We use logistic regression methods to assess the significance of air pollution levels based on the imputed values after modelling the relationship between binary health responses and assorted covariates such as measures of life style. Our findings prove negative; no significant relationship between chronic respiratory morbidity and air pollution is found. The imputation methodology is seen to be promising and might well be used in other such analyses.  相似文献   

14.
This paper describes a decision-support system based on landscape ecology and focused on the study of ecosystems’ health. System capabilities are illustrated with three cases of integrated coastal zone management (ICZM), in the Adriatic Sea (Italy): the lagoon of Venice and the Rimini and Ancona coastal areas. Indicators and indices are developed with a focus on sub-regional and local problems in coastal management, with a multi-scale approach based on landscape and seascape ecology. Land-use changes of the coastal areas were detected by analyzing two sets of satellite images. Indices combining satellite imagery, socio-economic and environmental indicators, and landscape and seascape maps were created, showing ecological changes, habitat loss and gaps in conservation policy. The approach used provides means for the identification of conflicts and for the assessment of sustainability. Results show that the lagoon of Venice plays an important role in mitigating and compensating the impacts of human activities, and needs to be protected and restored. The Rimini area shows high ecological footprint and development-intensity and low biocapacity. The Ancona area needs the protection of its natural coastal space from potential sources of anthropogenic impacts to maintain its sustainability. A model of environment changes is critical for formulating effective environmental policies and management strategies. The developed decision-support system provides a suitability map per each area analyzed, which can be used in order to maximize different policy objectives and reduce coastal conflicts.  相似文献   

15.
Coastal dunes are an essential part of beach-dune systems. Dunes systems have their own intrinsic values and provide a range of goods and services, including the protection of tangible goods located on the shoreline affected by waves, storms, and sea erosion. Dunes also act as repositories of biodiversity that have their exclusive habitat in dune communities, and the aesthetic value of dune landscapes derived from unique plant communities and landforms is also of great importance. Nevertheless, dune systems on developed coasts suffered a drastic decline in geomorphological and ecological quality throughout the last century. Catalonia (Spain, NW Mediterranean Sea) is no exception, and the coastal dune systems which were present in the early 20th century have now disappeared due to urbanization. The regeneration of dune systems is of crucial importance in this context. The aim of this study is to assess the current status of dune systems in Catalonia in order to determine their future prospects based on beach characteristics, those beaches likely to host dunes being determined according to their width and sediment type. The results of our study show that nowadays most dune systems in Catalonia are not developed due to human pressure on the beaches. Only those beaches located in the natural protected areas in Roses Bay, Baix Ter Bay, the Llobregat Delta, and especially the Ebro Delta, have the right characteristics to host well-developed dune systems. That said, 30% of sandy beaches in Catalonia have a width of over 35 metres; wide enough to host well-developed dune systems if appropriate integrated beach management is applied. The methodology used in this research also provide a tool to assess which are the beaches that can host dunes on other developed shores in the Mediterranean area.  相似文献   

16.
Cattle Grazing Mediates Climate Change Impacts on Ephemeral Wetlands   总被引:1,自引:0,他引:1  
Abstract:  Climate change impacts depend in large part on land-management decisions; interactions between global changes and local resource management, however, rarely have been quantified. We used a combination of experimental manipulations and simulation modeling to investigate the effects of interactions between cattle grazing and regional climate change on vernal pool communities. Data from a grazing exclosure study indicated that 3 years after the removal of grazing, ungrazed vernal pools dried an average of 50 days per year earlier than grazed control pools. Modeling showed that regional climate change could also alter vernal pool hydrology. Increased temperatures and winter precipitation were predicted to increase periods of inundation. We evaluated the ecological implications of interactions between grazing and climate change for branchiopods and the California tiger salamander (  Ambystoma californiense ) at four sites spanning a latitudinal climate gradient. Grazing played an important role in maintaining the suitability of vernal pool hydrological conditions for fairy shrimp and salamander reproduction. The ecological importance of the interaction varied nonlinearly across the region. Our results show that grazing can confound hydrologic changes driven by climate change and play a critical role in maintaining the hydrologic suitability of vernal pools for endangered aquatic invertebrates and amphibians. These observations suggest an important limitation of impact assessments of climate change based on experiments in unmanaged ecosystems. The biophysical impacts of land management may be critical for understanding the vulnerability of ecological systems to climate change.  相似文献   

17.
虾池环境生物修复作用菌的模拟应用   总被引:11,自引:1,他引:11  
在模拟条件下,研究了虾池环境生物修复作用菌对对虾养殖环境中虾池有机物的降解过程,结果表明,虾池环境生物修复作用菌能明显改善虾池环境,降低有机物的含量(4d后CODMn的去除率为43.52%)。将大分子的有机物降解为小分子的无机氮等;对虾养殖池中作用菌的使用量以262.5kghm^-2为宜。图3参13  相似文献   

18.
Researchers are increasingly turning to network theory to understand the social nature of animal populations. We present a computational framework that is the first step in a series of works that will allow us to develop a quantitative methodology of social network sampling to aid ecologists in their social network data collection. To develop our methodology, we need to be able to generate networks from which to sample. Ideally, we need to perform a systematic study of sampling protocols on different known network structures, as network structure might affect the robustness of any particular sampling methodology. Thus, we present a computational tool for generating network structures that have user-defined distributions for network properties and for key measures of interest to ecologists. The user defines the values of these measures and the tool will generate appropriate network randomizations with those properties. This tool will be used as a framework for developing a sampling methodology, although we do not present a full methodology here. We describe the method used by the tool, demonstrate its effectiveness, and discuss how the tool can now be utilized. We provide a proof-of-concept example (using the assortativity measure) of how such networks can be used, along with a simulated egocentric sampling regime, to test the level of equivalence of the sampled network to the actual network. This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and R. James).  相似文献   

19.
Wave hydrodynamics around a multi-functional artificial reef at Leirosa   总被引:1,自引:0,他引:1  
This paper describes an application of the Boussinesq-type COULWAVE model to study the wave hydrodynamics in the vicinity of a multi-functional artificial reef (MFAR). This reef is under investigation and consists of a supplementary protection solution for the Leirosa sand dune system located at South of Figueira da Foz, on the Portuguese West coast. Such installation near the coastline is expected to contribute to enhance the surfing conditions in the area, protect the sand dune system in the surroundings of Leirosa beach, and increase its environmental value. Numerical calculations with the COULWAVE model were performed for four test cases, considering two reef geometries (differing in the reef angle) and two incident wave conditions (storm condition and a common wave condition). Comparisons between the results obtained, in terms of wave heights and breaking line positions allow us to assess the influence of the reef on the hydrodynamics near the beach and around the reef. Moreover, the reef performance was analysed in terms of surfability and coastal protection. The surfability parameters (breaker height, Iribarren number and peel angle) were calculated for each test case using the numerical wave heights, wave directions and wave breaking positions. Comparisons of parameters allow characterizing the most appropriate configuration of the reef to improve the surfing conditions in the study area. A methodology based on numerical free surface elevations and horizontal velocity components was developed to calculate wave directions, since this is not a direct output of the COULWAVE model. Concerning coastal protection, analyses of the mean currents around the reef were used together with observations of the velocity cells near the shoreline as an indication of the sediment transport.  相似文献   

20.
Abstract:  Conservation organizations and public agencies are interested in identifying and prioritizing areas for conservation action, often acquisition or easements. Typically, this requires the use of uncertain data and vaguely defined decision criteria. I developed a decision support system to address these uncertainty issues and assist in evaluating conservation opportunities for the endangered California tiger salamander ( Ambystoma californiense ) in Santa Barbara, California. Functionally defined planning units were used to aggregate data on land suitability, land cover change, salamander presence, and movement risk along potential linkages between breeding ponds. I used a fuzzy-logic-based inference engine to evaluate the planning units and rank the relative suitability of interpond linkages for conservation action. The sensitivity of the rankings was considered with respect to uncertainty in salamander occurrence data and the relationship between land-cover-change threats and site suitability. All linkages were substantially degraded, but five areas were consistently identified with high relative suitability for conservation action despite differences in assumptions and uncertainty in biological data. The combination of functionally defined planning units and a fuzzy-logic-based decision support system provides a general framework for considering the suitability of sites for conservation action.  相似文献   

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