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1.
A GIS-based vulnerability assessment of coastal natural hazards,state of Pará, Brazil 总被引:1,自引:0,他引:1
Studies carried out in the NE coastal zone of the State of Pará (Brazil) have recorded, in the last 25 years, numerous evidence
of natural impacts of the flood and erosion processes. As a consequence, diverse strategies and measures of population adaptation
have been implemented but with limited success. Therefore, in order to subsidize the Coastal Zone Management Program of Pará,
this paper aims to identify, assess and classify natural and socio-economic vulnerabilities of this coastal zone by means
of a Geographical Information Systems (GIS)-based composite coastal vulnerability index (CVI). In spite of the data problems
and shortcomings, using ESRI’s Arcview 3.2 program, the CVI score, to classify, weight and combine a number of 16 separate
natural and socio-economic variables to create a single indicator provides a reliable measure of differences (5 classes) among
regions and communities that are exposed to similar ranges of hazards. The results are presented in three maps referred to
as Natural, Socioeconomic and Total Vulnerability. The confidence associated with the results obtained, the need to utilize
another variables, and to frequently update the ones used already were analyzed and discussed. 相似文献
2.
Francisco Taveira Pinto 《Journal of Coastal Conservation》2004,10(1):147-157
The practice of coastal zone management in Portugal is very recent. Key issues and considerations about natural shoreline
dynamics, main policy instruments, and lessons learned from the EU Demonstration Programmes on Integrated Coastal Zone Management
in Portugal will be outlined in this paper in an attempt to understand how the practice of ICZM and its prospects are. Coastal
zone management problems and their associated side effects, as well as national and international evolution patterns will
be drawn. Some means of achieving better coastal zone management practices and ways of addressing some of its forefront issues
are also identified. Special attention will go to erosion problems. The pressure induced by urban development and economic
activities on coastal areas is increasing. Poor sediment availability combined with years of neglected management and over-exploitation
of resources have had a negative impact, and there are many areas showing evidence of coastal erosion. There is a need to
improve policies and instruments of coastal planning and management. Coastal zone management plans are being developed for
the nine sectors of the continental Portuguese coast, providing a full analysis of coastal systems and a delimitation of uses
in relation to the carrying capacity of the shoreline. 相似文献
3.
This contribution presents an introduction to a series of papers on integrated scientific approaches presented at the San
Feliu Euroconference on transdisciplinary coastal management research. Coastal management is a challenging area for the integration
of social and natural sciences. The papers provide a basis for ongoing cross-disciplinary research. 相似文献
4.
Management of the coastal zone for the purposes of conservation and sustainability is a well-described concept in the literature.
This paper describes the importance of modelling various forms of maritime traffic as an intrinsic element of this process.
Effective use of GIS in this context implies extensive data acquisition and cleaning, vessel path simulation, traffic density
maps, and incident (spills or accidents) distribution when applicable. Risks can be determined by evaluating detrimental occurrences
relative to exposure levels. Effective visualization and quantitative analyses can then be fruitfully applied to various coastal
zone management spheres, such as oceans use planning, emergency response planning, and marine protected area delineation. 相似文献
5.
Sea surface colour data, derived from the Coastal Zone Colour Scanner (CZCS) archive, have been used to assess the space/time
variability of coastal plumes and run-off in the Mediterranean Sea. A time series of 2645 scenes, collected by the CZCS from
1979 to 1985, was processed to apply sensor calibration algorithms, correct for atmospheric contamination, and derive chlorophyll-like
pigment concentration. Individual images, remapped on a 1-km2 pixel grid, were generated for each available day, and then mean values calculated pixel by pixel to form monthly, seasonal
and annual composites. The results obtained must be taken with caution, due to the CZCS limitations in the quantitative assessment
of bio-optical pigments when high concentrations of dissolved organics or suspended sediments are present, e.g. along littorals
or within plumes. Marked differences appear in the distribution of water constituents between coastal zones and open sea,
northern and southern near-coastal areas, western and eastern sub-basins. The oligotrophic character of the basin contrasts
with areas of high concentration related to river plumes—Ebro (Ebre), Po, Rhone, Nile—, coastal run-off patterns, and persistent
mesoscale features (e.g. coastal filaments and eddies). Seasonal variability appears to be high, with higher concentrations
occurring over most of the basin in the cold season, when climatic conditions are favourable to coastal run-off and vertical
mixing. Atmospheric forcing (wind and rainfall over continental margins) could play an important role in establishing the
observed space/time distribution of water constituents. The impact of continental interactions (fluvial and coastal run-off),
or that of exchanges between coastal zone and open sea, could have paramount influence on the biogeochemical fluxes in the
entire basin. 相似文献
6.
In 1990 the Dutch government decided to stop any further long-term landward retreat of the coastline. This policy choice for
a ‘dynamic preservation’ is primarily aimed at safety against flooding and at sustainable preservation of the values and interests
concerning the dunes and beaches. Five years later, a first overview of the benefits and bottlenecks of the new coastal defence
policy could be presented, which was published in the second governmental coastal report ‘Kustbalans 1995’ (coastal balance
1995). This consists of three elements: (1) evaluation of the implementation of ‘dynamic preservation’, (2) the consequences
of several natural and anthropogenic developments in the coastal zone and (3) integrated coastal zone management. The present
report describes experiences of Dutch coastline management and summarizes the main conclusions of the second governmental
report.
The overall conclusion of the evaluation study is that the 1990 choice for ‘dynamic preservation’ was right. Sand supply is
an effective method of coastline maintenance, which also serves functional uses in the beach and dune area. However, nearly
a doubling of the supply volume is necessary to compensate for sand losses in the coastal zone. A more integrated management
of the coastal zone is necessary to find an equilibrium between the interests of socio-economic development and the maintenance
of a natural, dynamic system. 相似文献
7.
In 1990 the Dutch government decided to stop any further long-term landward retreat of the coastline. This policy choice for
a ‘dynamic preservation’ is primarily aimed at safety against flooding and at sustainable preservation of the values and interests
concerning the dunes and beaches. Five years later, a first overview of the benefits and bottlenecks of the new coastal defence
policy could be presented, which was published in the second governmental coastal report ‘Kustbalans 1995’ (coastal balance
1995). This consists of three elements: (1) evaluation of the implementation of ‘dynamic preservation’, (2) the consequences
of several natural and anthropogenic developments in the coastal zone and (3) integrated coastal zone management. The present
report describes experiences of Dutch coastline management and summarizes the main conclusions of the second governmental
report.
The overall conclusion of the evaluation study is that the 1990 choice for ‘dynamic preservation’ was right. Sand supply is
an effective method of coastline maintenance, which also serves functional uses in the beach and dune area. However, nearly
a doubling of the supply volume is necessary to compensate for sand losses in the coastal zone. A more integrated management
of the coastal zone is necessary to find an equilibrium between the interests of socio-economic development and the maintenance
of a natural, dynamic system. 相似文献
8.
Coastal zones in Portugal, as interface areas between land and sea, have problems related to the growing human pressure in
terms of changes in land use associated with urban and industrial occupation, new accessibility (ports, motorways) and traffic
flows, intensification of recreational use (beaches, water sports) and excessive fishing. Impacts include deterioration of
water quality and sediments; alteration and degradation of natural habitats; new hydrodynamic situations; major landscape
changes: and rapid changes in habits and way of life of the local populations and increased exposure of populations and assets
to natural and induced risks (storms, accidents, spills, explosions).
Plans for the Management of the Coastal Zone (POOC) have been developed and seven of them have been approved, while two similar
plans are at a final stage of preparation. Together they cover the entire coast of Portugal. Their implementation and assessment
could be a first step towards an integrated management of the Portuguese coastal zones. River Basin Management Plans (PBH)
have been concluded and recently approved for the whole country. However, these plans do not consider estuarine systems and
some other issues related to coastal systems. The National Water Plan (PNA) is under public presentation and discussion. Several
‘key messages’ are presented in this paper as a contribution for assessment of the proposals of this plan on issues related
with coastal waters. 相似文献
9.
This paper presents the results from a study which was undertaken to monitor, map and quantify salt marsh change along 440
km of shoreline within the county of Essex, south-east England, between 1973 and 1998. Results indicate that during this 25-yr
period, 1000 ha of salt marsh has been lost in Essex, primarily due to coastal erosion. This figure represents ca. 25% of
the total salt-marsh area originally present in Essex in 1973. The salt marshes of Essex are important nature conservation
areas, with many sites designated as Special Protection Areas under the EC Birds Directive (79/409/EEC) and as Special Areas
of Conservation under the EC Habitats Directive (92/43/EEC). Salt marshes are also natural features which significantly dissipate
wave and tidal energy, thereby playing an important role in contributing to effective coastal defence. The large-scale loss
of salt marsh in Essex has, therefore, implications for both nature conservation and flood defence. Potential hypotheses for,
and implications of such losses are discussed in this paper, together with the identification of potential management approaches
to alleviate the losses. 相似文献
10.
In 1990, the Government and Parliament of the Netherlands decided on a new national policy for coastal defence. To ensure
the enduring safety of the low-lying polders as well as the sustainable preservation of the coastal dunes, it was decided
to maintain the coastline in its 1990 position.
The main method for coastline preservation in the Netherlands is beach nourishment. Since 1991, approximately 7 million m3 of sand is added to the Dutch beaches annually. From an evaluation study of sand nourishment projects it is concluded that
nourishment is an effective and efficient method to preserve the coastline. The evaluation study also proves that nourishment
projects should be ‘tailor-made’, taking the local morphological and hydraulic conditions into account. The first results
of an experimental shoreface nourishment are discussed.
The choice for nourishment as the principal method to combat erosion is well in line with the intention to restore the natural
dynamics of the dune-coast in the Netherlands. The key probably is a less strict policy with regard to the maintenance of
the foredunes. Plans for the development of typical coastal features such as slufters*, wash-overs, blow-outs and mobile dunes are currently under discussion.
A slufter is a breakthrough in the first dune-ridge whereby the sea invades former dune slacks or beach plains situated behind
the duneridge. In this way a tidal marsh is formed within the dune zone. 相似文献
11.
John Kiousopoulos 《Journal of Coastal Conservation》2008,12(1):19-25
The general objective of this paper is to trigger off the development of a more comprehensive approach to Hellenic coastal
areas (in the perspective of territorial cohesion), at local level and especially along the non-urban areas close to the sea.
Methodological issues linked to the building of an appropriate coastal database constitute the key goal of this paper (the
space and time scale, the relationship to the already proposed set of indicators, the impact of driving forces and policies,
the possible sources of data and their feasibility etc.). Furthermore, specific emphasis should be given to the choice of
new indicators, particularly for the coastal abiotic environment and the land cover/uses along coastal areas, especially near
the seafront. Those indicators should be able to aid the formation (in the near future) of an algorithm linked to the total
man-made activities in coastal areas. In conclusion, this paper will be considered successful if the just above illustrated
objectives could enrich the argument about the typology of coastal areas and the development of a spatial (coastal) observatory.
Actually, this paper is part of a broader research of the author regarding the monitoring of coastal spatial changes in different
scales (AMICA, “Appraisal of man-made interventions along the Hellenic coastal areas”). This research aims to broaden the
coastal knowledge (not only by means of coastal data) on behalf of all stakeholders been implicated into sustainable spatial
planning, integrated coastal management and the strategic environmental assessment along coastal areas.
相似文献
John KiousopoulosEmail: |
12.
Carles Ibàñez Antoni Canicio John W. Day Antoni Curcó 《Journal of Coastal Conservation》1997,3(2):191-202
The Ebre (Ebro) Delta is one of the most important wetland areas in the western Mediterranean. Ca. 40 % of the delta plain is less than 0.5 m above mean sea level and part of the southern margin of the delta is at mean sea level in an area protected by dikes. Both mean rates of secular subsidence in the Ebre Delta and eustatic sea level rise are ca. 1 – 2 mm/yr. Thus, the present annual relative sea level rise (RSLR) rate in the Ebre Delta may be at least 3 mm/yr. Measured accretion rates in the delta range from 4 mm/yr in the wetlands surrounding the river mouth to <0.1 mm/yr in impounded salt marshes and rice fields. The annual sediment deficit in the delta plain to offset RSLR is close to 1 million m3/yr. Accretion rates in the rice fields prior to the construction of large dams in the Ebre watershed were higher than RSLR rates, from 3 – 15 mm/yr. At present, >99 % of the riverine sediments are retained in the reservoirs and rice fields are losing ca. 0.2 mm/yr. Future management plans should take RSLR into account and include control of freshwater and sediment flows from the river in order to offset negative effects from waterlogging and salt intrusion, and maintain land elevation. This will include the partial removal of sediments trapped behind the Ribarroja and Mequinença dams. Stocks and inputs of sediments in the corresponding reservoirs are large enough for land elevation of ca. 50 cm in the whole delta plain. Advantages of this solution include (1) new sediments to the delta to offset subsidence (via rice fields) and coastal retreat, (2) enhanced functioning of the delta (productivity and nutrient processing), (3) avoidance of accumulation of sediments in the reservoirs. Hence, it is important to manage river discharges at the dams from an integrated viewpoint, whereas currently only hydropower and agricultural requirements are considered. It is also crucial to maintain periods of high discharge, to have enough river energy to transport as much sediments as possible. 相似文献
13.
The role of human actions in evolution and management of foredunes in The Netherlands and New Jersey, USA 总被引:1,自引:0,他引:1
The rationale and methods of construction of foredunes in The Netherlands and New Jersey, USA are identified and used to explain
their genesis, locations, mobility, internal and external characteristics and temporal scales of evolution. Dunes are then
ranked according to the degree they are modified by human processes. The lower level of protection required of foredunes in
New Jersey and the greater amount of modification by municipal managers and shorefront residents results in smaller dunes
and greater variety of sizes, shapes, methods of construction and alterations. As a result, humans are considered intrinsic
agents in evolution of dune landforms and landscapes. Higher, wider, better vegetated foredunes occur in The Netherlands due
to greater frequency of onshore winds and greater emphasis on sea defence at the national level. Natural processes play a
greater role in the evolution of landforms. Human actions are considered extrinsic at this scale but intrinsic at the scale
of landscapes. The change in foredunes from natural features to artifacts reveals the significance of humans in the modification
of coastal landforms and reflects the changing perception of the role of these landforms in the coastal landscape. 相似文献
14.
Nikolaos P. Nikolaidis Aristomenis P. Karageorgis Vasilios Kapsimalis Paraskevi Drakopoulou Nikolaos Skoulikidis Horst Behrendt Zlatko Levkov 《Ecological modelling》2009
The estimation of nutrient fluxes, the determination of spatial and temporal response and the understanding of biogeochemical changes in the past, present and future in the Axios River catchment, in Greece, as well as the impacts to the coastal zone of Thermaikos Gulf were accomplished by the use of harmonized watershed and coastal zone models. The mathematical model MONERIS was the watershed management model that was used to model the export loads of nutrients in Axios River. MONERIS was developed to estimate the nutrient inputs into river basins by point sources and various diffuse pathways. Watershed hydrologic and water quality data were collected and synthesized to develop input data sets for the simulation of Axios River catchment. The model was modified to better assess organic nitrogen export loads in Mediterranean watersheds. The results showed the importance of agricultural and livestock activities, concerning their nutrients emissions in the River. MONERIS was integrated with the coastal zone model WASP 6.0 to assess the impacts of the nutrient loads to the eutrophication status of the coastal zone. Several management scenarios were assessed. Management scenarios included measures for reduction in the emissions from the fertilizer plant of Veles, removal of phosphorous from the detergents in FYROM, treatment of urban wastes to EU Standards, reduction in N-fertilizer input, reduction in erosion and the green scenario that represented the maximum reduction scenario of all the measures together. The model simulations indicated that the coastal zone of Axios mouth will be eutrophic for nitrate (2.69–3.34 μM) and phosphate (0.2–0.68 μM) and upper mesotrophic for chlorophyll-a (0.74–1.45 μg/l) for the scenarios tested. The results suggest that the impact of the management scenarios will be largely negligible (no change in trophic status) for the Thermaikos Gulf sector nearby the Axios River due to additional sources such as the loads from Thessaloniki's waste water treatment plant which appear to affect the region to a greater extent. The integration of watershed and coastal zone models can be used to assess management scenarios in order to illustrate the significance of various land use practices to the eutrophication of the Gulf. 相似文献
15.
New legislation for the protection of inland surface waters, transitional waters, coastal waters and ground waters has recently
been established in Italy. This law presents a new integrated approach, where all water bodies are considered as complex ecosystems
to be studied in each of their components. The new concept of environmental quality of the water body, based on the ecological
and chemical status, is also introduced. At the same time (i.e. the end of 2000), the European Community approved the European
Water Framework Directive based on the same basic environmental concepts and criteria of the new Italian law. This paper analyses
the important points and innovations required by the new Italian legislation for monitoring and classification of marine coastal
waters. Details of definitions, parameters, analysis and monitoring programs are discussed. A comparison with the European
Water Framework Directive is eventually given, underlining the specific characteristics of the Mediterranean sea, which have
to be taken into consideration when applying the European Directive to this particular ecoregion. 相似文献
16.
17.
Mamdouh Fahmy 《Chemistry and Ecology》2013,29(1):67-77
In order to provide a background picture of the water quality of the Egyptian Red Sea a number of hydrological and chemical parameters have been measured bimonthly in 2000. Few data are available on this area, which is apparently subjected to an increasing human impact due to recreational (swimming and diving), industrial (mainly phosphate shipping and industry) and fishing/harbor activities. The results of the present study indicate that changes in the salinity and pH were not significant with highly oxygenated seawaters. The levels of suspended solids (as total suspended matter, TSM) and chlorophyll-a (Chl-a) were generally low and showed an homogeneous distribution in the study region. The ratio of chlorophyll-a to total suspended matter concentrations increased between November and March and decreased from May to September. Chlorophyll-a was significantly correlated with transparency and total suspended matter concentrations in July, September and November. Nitrogen, phosphorus and reactive silicate concentrations were generally low, and allowed classifying the Egyptian Red Sea coastal water as oligotrophic to mesotrophic. The middle region of the study area, which was located between Safaga and Qusair displayed relatively high phosphate contents when compared with other coastal areas. The high values of N:P ratios indicate that PO 4 -P is the limiting factor for phytoplankton growth in the Red Sea coastal waters, with the possible exception of the middle region. Significant relationships were found between chlorophyll-a concentrations and nutrient levels in different sampling periods. Spatial distribution patterns of the studied variables revealed that productivity of the Red Sea coastal waters is mostly controlled by phosphate concentrations, salinity, temperature and dissolved oxygen. 相似文献
18.
Paola Rivaro Carmela Ianni Serena Massolo Nicoletta Ruggieri Roberto Frache 《Chemistry and Ecology》2004,20(4):279-307
The main objective of this paper is to present vertical and horizontal patterns of dissolved oxygen and nutrients found during four seasonal surveys (March, June, September and December 2000) in the Southern Adriatic Sea coastal waters. The multivariate technique Principal Component Analysis has been applied to our dataset considering the following parameters: seawater temperature, salinity, dissolved oxygen and nutrients (nitrate, nitrite, phosphate, silicate). The resulting plot shows in a self-explanatory way that a seasonal trend was not observable in the investigated period and that no significant differences occur between the stations sampled in the Taranto Gulf and those along the Adriatic coast. Water column stratification persists in all seasons, except in spring, in the shallowest stations. The surface layer is characterized by a low nutrient content. The influence of the Northern Adriatic Surface Water in the Southern Adriatic sub-basin seems to be very low and can be traced by nitrate and silicate only in spring and winter. Regarding deep waters, nitrate distribution shows an increasing gradient moving from the coast to the open sea, having the lowest concentration in the shelf area and the highest in the most offshore stations of the Otranto Strait. In the Otranto Strait area the vertical distributions of physical and chemical parameters show, at middle depths, the inflow of Levantine Intermediate Water, traced by both the maximum of salinity, nitrate and phosphate and the minimum of oxygen. The LIW signal is lost moving northward. The outflow of Adriatic Dense Water is less evident, being traced only in spring by an oxygen increase at the bottom layer in the shelf area. The N:P ratio is highly variable but in the range already observed in the Southern Adriatic, suggesting a P-limitation, which can both contribute to the low primary productivity of the area and support the N:P ratio anomaly of the Eastern Mediterranean. 相似文献
19.
The results of the daNUbs-project deliver a basis for a proper management of nutrients in the Danube Basin. The understanding of the sources, pathways, and sinks of nutrients in the Basin and their effects on the Western ad North-Western Black Sea (WBS) ecosystem has been improved. Quantitative models on the emission of nutrients, their transport along the rivers, and their impact on the WBS have been further developed and combined. Phosphorus loads discharged by the Danube are 30-50% lower than in the 1980s (dissolved P even to a higher extent). Nitrogen emissions have decreased considerably as well. The lower nutrient discharges from the Danube have led to a significant improvement in the WBS ecosystem. Current low discharges of N and P to the WBS are the result of (1) improved nutrient removal from waste water in Germany, Austria, and Czech Republic, (2) reduced P-discharges from detergents and (3) the consequences of the economic crisis in central and eastern European countries following the political changes of 1989/1990. As the decrease is partly due to the economic breakdown in the formerly communist countries, economic development in these countries has to go along with proper nutrient management. Otherwise, the situation in the WBS ecosystem will deteriorate again. 相似文献
20.
苏北盐城海岸带陆源氮磷污染负荷估算初探 总被引:3,自引:1,他引:3
海岸带陆源氮磷污染输入是导致近海赤潮的主要原因,但目前尚缺乏系统的调查研究。文章采用野外实地调查和文献调研相结合的方法,从农田径流、养殖废水排放、居民生活污水和工业废水排放等几个方面,初步估算了盐城海岸带陆源氮磷污染负荷的分配情况。结果表明,盐城海岸带主要陆源污染源中,养殖水域氮磷排放总量为7641t和480t,分别占排放总量的75.1%、63.5%;其次为居民工矿的生活生产污水,其氮磷排放量为2083t和232t,占总排放量的20.5%、30.7%;农田目前看来不是盐城海岸带主要的陆源污染源,排放量仅占4.4%和5.8%。在当前海岸带陆源污染源治理中,除采取有力措施控制养殖水域养分流失外,农村和乡镇生活生产污水的排放也应引起重视。 相似文献