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1.
滨海湿地是雁鸭类水鸟的重要栖息地,然而高强度的海岸圈围工程对滨海湿地生态系统和鸟类栖息地造成了显著影响,因此分析和研究海岸圈围对雁鸭类水鸟种群及栖息地的影响,对水鸟保护和滨海湿地资源可持续利用具有重要的理论和实践意义。位于长江口的横沙东滩,于2003年启动了海岸圈围促淤工程,工程的实施导致湿地生境和水鸟种群都发生着快速变化。本研究分别对2013、2015、2016和2017年,横沙东滩雁鸭类水鸟种群和生境因子的时空变化进行了调查与分析,通过拟合回归分析得到两者的相关关系,进一步探讨海岸圈围后生境的快速演替对雁鸭类水鸟种群产生的影响,从而提出海岸带圈围后水鸟栖息地的保护与管理对策。结果表明:1)海岸圈围工程的实施显著改变了滨海湿地的水鸟生境及种群特征。随着工程的推进,自然潮滩的盐沼湿地呈动态变化趋势;促淤区则随着泥沙的补给,新生了大面积的沼泽湿地;成陆区逐渐向淡水生态系统演替。伴随着生境的变化,雁鸭类水鸟种群逐渐从成陆区和自然潮滩向促淤区转移。2)不同生境类型影响雁鸭类种群数量特征的生境因子不同。未实施圈围的自然潮滩影响雁鸭类水鸟数量的主要因素是海三棱藨草/藨草群落面积;正在实施圈围的促淤区的主要影响因素是挺水植物面积、植被归一化指数(NDVI)和无植被覆盖水域面积;已圈围的成陆区主要影响因素为沉水植物面积。综上,雁鸭类水鸟偏向选择具有开阔水域、充足食物供给和相对较低植被盖度的生境类型。对于海岸圈围区域,若能合理利用圈围土地,保留部分区域为湿地,并根据水鸟的生境需求,适当营造水鸟适宜的栖息地,可在一定程度上减缓圈围工程对水鸟的影响,实现滨海湿地水鸟栖息地保护和湿地资源可持续利用的动态平衡。  相似文献   

2.
滨海湿地是雁鸭类的重要栖息地,然而高强度的海岸圈围工程对滨海湿地生态系统和鸟类栖息地造成了显著影响,因此分析和研究海岸圈围对雁鸭类种群及栖息地的影响,对水鸟保护和滨海湿地资源可持续利用具有重要的理论和实践意义。位于长江口的横沙东滩,于2003年启动了海岸圈围促淤工程,工程的实施导致湿地生境和水鸟种群都发生着快速变化。本研究分别对2013、2015、2016和2017年,横沙东滩雁鸭类种群和生境因子的时空变化进行了调查与分析,通过拟合回归分析了两者的相关关系,探讨海岸圈围后生境的快速变化对雁鸭类种群产生的影响,从而提出海岸带圈围后水鸟栖息地的保护与管理对策。结果表明:1)海岸圈围工程的实施显著改变了滨海湿地的水鸟生境及种群特征。随着工程的推进,自然潮滩的盐沼湿地呈动态变化趋势;促淤区则随着泥沙的补给,新生了大面积的沼泽湿地;成陆区逐渐向淡水生态系统演替。伴随着生境的变化,雁鸭类种群逐渐从成陆区和自然潮滩向促淤区转移。2)不同生境类型影响雁鸭类种群数量特征的生境因子不同。未实施圈围的自然潮滩影响雁鸭类数量的主要因素是海三棱藨草/藨草群落面积;正在实施圈围的促淤区的主要影响因素是挺水植物面积、植被归一化指数(NDVI)和无植被覆盖水域面积;已圈围的成陆区主要影响因素为沉水植物面积。综上,雁鸭类偏向选择具有开阔水域、充足食物供给和相对较低植被盖度的生境类型。对于海岸圈围区域,若能合理利用圈围土地,保留部分区域为湿地,并根据水鸟的生境需求,适当营造水鸟适宜的栖息地,可在一定程度上减缓圈围工程对水鸟的影响,实现滨海湿地水鸟栖息地保护和湿地资源可持续利用的动态平衡。  相似文献   

3.
Invasive smooth cordgrass (Spartina alterniflora, hereafter Spartina) has been expanding rapidly in the estuarine wetlands at Chongming Dongtan (East China) at the expense of native sea-bulrush (Scirpus mariqueter, hereafter Scirpus) and common reed (Phragmites australis, hereafter Phragmites). To examine the potential impacts of the Spartina invasion on bird diversity, we compared the abundance and species richness of birds in habitats created by Spartina, Phragmites, Spartina mixed with Phragmites, Scirpus, and the bare intertidal zone at Chongming Dongtan in spring 2008. Most birds were recorded in the native habitats, with songbirds and breeding birds being most abundant in the Phragmites habitats, and waterbirds and migrants being most abundant in the Scirpus habitats and bare intertidal zone. Both species number and population densities of birds were lower in the exotic Spartina habitats than in the other four habitats. Although some songbirds and breeding birds used the Spartina-invaded habitats, and even preferred Spartina-invaded habitats to Scirpus habitats and bare intertidal zone, their densities were lower in the Spartina-invaded habitats than in the native Phragmites habitats. This might have resulted from the dense Spartina stands restricting bird movement and providing insufficient useable food for most birds. We conclude that the spread of exotic Spartina has negative impacts on local bird communities. Because Chongming Dongtan is an important stopover site for energy replenishment of shorebirds in the East Asian–Australasian Flyway, urgent measures are needed to control further spread of Spartina and to restore the native habitats for birds.  相似文献   

4.
Next generation turbines can be installed to exploit tidal energy resource in estuaries. However, the ecological implications of such deployments remain unknown. Accordingly, this study is focused on the impact of tidal farms on intertidal areas and associated waterbird habitats in estuaries. A numerical model simulates the hydrodynamic conditions of the Solway Firth, comprising one of the most extensive intertidal zones in the UK. The effects of tidal farms with different turbine densities have been evaluated in terms of changes to the areas of habitat for wetland bird species of conservation importance. The results suggest that any habitat loss may be minor and that in some cases there may be an increase (also small) in the area of important habitat. The percentage change in intertidal areas is also considerably lower than that expected to result from tidal barrages of similar capacities, implying the potential for tidal farms to present an alternative solution for exploiting tidal energy in highly protected areas. The changes in the extent of intertidal habitat are not proportional to the energy dissipated by the tidal farm. Therefore a range of tidal farm designs should be evaluated in order to optimise installed capacity while minimising habitat loss. However, the site-dependency of the impacts and the complex responses to change of estuarine ecosystems reinforce the requirement for detailed studies to be undertaken for each specific location and array configuration. The methodology presented here is appropriate for such assessments as it can be applied to different locations and turbine types.  相似文献   

5.
During deteriorated prey availability, purely pelagic, specialised seabird species have to alter their feeding strategy by extending foraging radii and/or time spent at sea or reducing feeding intervals of chicks. In contrast, more generalised species such as the opportunistic black-headed gull (Larus ridibundus) breeding at the German North Sea coast, can be assumed to react on prey shortages by switching foraging habitats. The coastal zone of the German North Sea provides a rich habitat mosaic consisting of the offshore zone, tidal flats and terrestrial habitats. Thus, we expected distinct temporal and spatial patterns of habitat switch in accordance with prey availability and environmental constraints. We carried out ship-based and aerial surveys as well as dietary analyses and observations on flight activity. We found a significant switch from terrestrial to marine feeding sites both on a daily basis (related to tidal cycle) and over the whole breeding season. Most likely, the latter switch is the result of lower prey availability in the terrestrial habitats and an increasing quality (in terms of prey abundance and energy intake) of the marine area. While there was only moderate variability in habitat use among different years, we revealed significant differences in the diet of birds from different colonies. The high dietary plasticity and flexible feeding strategy, switching between terrestrial and marine prey is certainly of major importance for the success of an opportunistic avian top predator in a complex coastal zone. It is suggested that – compared to situations elsewhere – the number of breeding pairs of black-headed gulls in the German North Sea coast are still stable due to the switch of foraging habitats performed by individuals in this region.  相似文献   

6.
基于海岸带综合管理的理念,通过海域生态环境敏感性评价与海域生物多样性保护重要性评价,综合利用地理相关分析法、空间叠置法等定性和定量分区相结合的方法进行海洋生物多样性保护空间规划分区划界,提出了海洋生物多样性保护空间规划分区体系,将规划区域划分为生物多样性重点保护区、生物多样性养护区和生物多样性保护重点监督区.以福建泉州湾为案例,应用海洋生物多样性保护空间规划分区体系,得出泉州湾生物多样性保护极重要地区是泉州湾河口湿地省级自然保护区,泉州湾生物多样性保护比较重要地区是晋江河口、洛阳江河口、晋江南岸地区及清源山.泉州湾海洋生物多样性保护空间规划分区方案共划定26个分区,包括生物多样性重点保护区3个,生物多样性养护区14个,生物多样性保护重点监督区9个.泉州湾的应用结果表明,本研究提出的海洋生物多样性保护空间规划分区体系具有一定的可行性和可操作性,可为泉州湾生物多样性保护管理提供重要科学依据.  相似文献   

7.
射阳河口互花米草入侵对大型底栖动物群落的影响   总被引:1,自引:0,他引:1  
2008年11月至2009年10月,在盐城自然保护区射阳河口滩涂分别于潮间带、潮上带和潮沟中设置互花米草区与非米草区2类对照样地(共6类生境),按月份取样来研究大型底栖动物群落特征的差异,探讨互花米草入侵对底栖动物的影响。共发现大型底栖动物22种,隶属3门4纲17科,其中软体动物13种,节肢动物6种,环节动物3种。米草区和非米草区的物种组成不同,各生境在不同月份大型底栖动物的物种数、密度、生物量和Shannon-Wiener多样性指数均在不断波动,在潮间带上述指标均为In>Ig,潮上带除密度外均为Sn>Sg,潮沟边滩除个别月份外均为Cg>Cn;3类互花米草生境中大型底栖动物群落各项指标月间变动趋势基本一致(仅个别月份例外),均表现为Cg>Sg>Ig,互花米草生境存在共同的优势种,但数量有一定的差异。分别对潮间带、潮上带和潮沟中互花米草区与非米草区2类对照样地的物种数、密度、生物量以及Shannon-Weiner多样性指数H’进行生境-月份间无重复双因素方差分析,结果显示潮间带2类对照样地各项指标在生境间差异均极显著,月份间差异均不显著;潮上带2类对照样地各项指标生境间存在极其显著的差异(除密度外),月份间差异显著(除多样性外);潮沟2类对照样地生境间差异显著(除生物量外),月份间差异均显著。研究结果表明不同生境中的互花米草对底栖动物的影响不甚相同:潮间带互花米草的入侵降低了大型底栖动物的物种数、密度、生物量和多样性;潮沟米草的入侵提高了大型底栖动物的物种数、密度和多样性;而潮上带米草入侵对大型底栖动物的各指标影响不一。  相似文献   

8.
Coastal freshwater and tidal wetland habitats are being transformed as a result of increasing demand for commercial, residential and tourism activities. The consequence is a habitat seascape complex, comprising a mosaic of natural and engineered coastal features. This study used the freely available mapping tool (Google Earth) to define the extent of coastal engineering structures in the Great Barrier Reef World Heritage Area (GBR; Australia), a marine ecosystem of global biodiversity and cultural significance. Continuing threats to the heritage estate concomitant with expanding urban and industrial developments has raised concerns directed at the future conservation and resilience of the reef ecosystems, along with maintaining expected human lifestyles and livelihoods it provides. The data here shows that break walls and pontoons/jetties dominate development, contributing to approximately 10% (equivalent) of the coastline linear length. Most (60%) development occurs along the coastline or within the first few kilometres upstream along estuaries. While conservation and protection of natural coastal habitats is still preferred for the objective of fisheries production and biodiversity, managers must consider seascape implication/benefits more broadly when approving new marine infrastructure rather than a case-by-case approach which further contributes to an ad hoc mosaic seascape of natural and engineered habitats. Not only within the GBR heritage estate, but more broadly, coastal managers need to regard wider seascape connectivity processes during the assessment of any new development. There is an urgent need for policy and planning instrument reform that is inclusive of accumulative impacts of urban and industrial development in this heritage estate. Opportunities to include eco-friendly (green engineering) solutions, in the repair and revitalisation of existing artificial structures, is necessary in any new proposed urban and industrial development and expansion.  相似文献   

9.
Estuarine and nearshore marine areas are vital habitats for several fish and benthic invertebrates. The shore crab Carcinus maenas (Crustacea: Brachyura: Portunidae) inhabits a variety of coastal, estuarine and lagoon habitats. At low tide, habitat structural complexity may be most important for crabs in the intertidal, providing refuge from predation and desiccation. The quality of different vegetated and nonvegetated estuarine and rocky shore habitats in SW Portugal and SW England was evaluated for intertidal C. maenas populations. We estimated population density, size–structure, and potential growth (RNA/DNA ratios) to investigate habitat quality. Vegetated estuarine habitats supported higher crab densities, than nonvegetated estuarine and rocky shore habitats. Investigation of population size–structure revealed that all habitats seem important recruitment and nursery areas although estuarine habitats in SW Portugal appeared to support higher densities of new recruits than equivalent habitats in SW England. Significant variation was found in RNA/DNA ratios among habitats. Ratios were highest in the rocky shore suggesting a high quality habitat where growth potential is high. We speculate that competition from other top-predators (Pachygrapsus spp.) rather than low habitat quality may limit the occurrence of C. maenas in intertidal rocky shore habitats in SW Portugal. In estuarine environments RNA/DNA ratios were significantly higher in the vegetated than in the nonvegetated estuarine habitats in SW Portugal but not in SW England, suggesting geographic differences in the extent to which highly structure habitats represent high quality. Our results challenge the current paradigm that structured habitats are necessarily those of higher quality for C. maenas.  相似文献   

10.
The littoral zone of Chesapeake Bay contains a mosaic of shallow vegetated and nonvegetated habitats with biotic components that are sensitive to changes in biological and physical driving factors. Static and dynamic modelling frameworks provide an integrative way to study complex hydrodynamic and biogeochemical processes in linked estuarine habitats. In this study we describe a spatial simulation model developed and calibrated relative to a specific littoral zone, estuarine ecosystem. The model consisted of four distinct habitats that contained phytoplankton, sediment microalgae, Zostera marina (eelgrass), and Spartina alterniflora. There was tidal exchange of phytoplankton, particulate and dissolved organic carbon and dissolved inorganic nitrogen between the littoral zone ecosystem and the offshore channel. Physical exchange and biogeochemical transformations within the habitats determined water column concentrations in each habitat. Predicted subtidal water column concentrations and Z. marina and S. alterniflora biomass were within the variability of validation data and the predicted annual rates of net primary production were similar to measured rates. Phytoplankton accounted for 17%, sediment microalgae 46%, the Z. marina community 24% and S. alterniflora 13% of the annual littoral zone primary production. The linked habitat model provided insights into producer, habitat and ecosystem carbon and nitrogen properties that might not have been evident with stand-alone models. Although it was an intra-ecosystem sink for particulate carbon, the seagrass habitat was a DOC source and responsible for over 30% of the littoral zone carbon and nitrogen primary production. The model predicted that the Goodwin Islands littoral zone was a sink of channel derived POC, but a source of DOC to the surrounding estuary. The framework created in this study of estuarine ecosystem dynamics is applicable to many different aquatic systems over a range of spatial and temporal scales.  相似文献   

11.
黄河三角洲潮上带和潮间带不同生境微塑料分布规律   总被引:1,自引:0,他引:1  
微塑料是近年来广受关注的持久性污染物之一,对海洋生态系统有着不可忽视的潜在危害。河口三角洲作为典型的滨海盐沼湿地,属生态敏感地带,是海洋和陆地两大生态系统的交错地带。选取黄河三角洲潮上带和潮间带盐沼裸斑、翅碱蓬、柽柳、芦苇和潮沟五种典型生境开展土壤微塑料进行采样调查并分析其分布规律。结果表明,黄河三角洲潮上带及潮间带土壤中塑料的整体丰度范围在7~147个/kg,相比世界范围内其他滨海地区属于中等水平,其中翅碱蓬区是微塑料平均丰度最高的区域。整体而言,在各材质中,聚乙烯材质微塑料的检出比例最大,达29.53%;而在各形状中,碎片状微塑料占比最大,达38.88%,其次是颗粒状微塑料,占比37.09%,二者比例接近,为研究区微塑料的主要形态。潮汐作用对微塑料的分布有重要影响,微塑料在距离海岸较近的样点丰度较低,而在高潮线附近明显聚集,同时在植被覆盖区微塑料丰度也明显升高。黄河三角洲国家级自然保护区内人类活动强度较低,但仍面临着来自原位风化降解、潮汐风力搬运等多种潜在来源的微塑料污染。综上,对河口湿地微塑料污染的治理与防护,对于维持区域生态系统稳定与健康具有重要意义。  相似文献   

12.
One of the main effects of urbanization on coastal areas is through the discharge of sewage, which increases nutrient concentrations in the receiving environment. Salt marshes, like other coastal marine environments, are limited by nutrients, mainly nitrogen, and thus increasing nutrient loadings to a marsh may have consequences on marsh characteristics. We evaluated how the effects of nutrient enrichment in the form of sewage input, affected the vegetation structure and bird assemblages in a Spartina alterniflora salt marsh system near Bahía Blanca, Argentina (39° 01' S - 56° 25' W). Surveys of nutrient concentration, vegetation and birds were made at three different distances from the sewage discharge source. The concentration of ammonium, phosphate, and nitrate and the percent organic matter was higher in marshes nearest to the sewage discharge source. Bird composition and abundance, and vegetation physiognomy changed along a gradient of nutrient concentration. The increased habitat complexity found near the areas of higher nutrient concentration was exploited by birds that use neighboring interior and coastal habitats, including Spartina densiflora marshes, freshwater marshes and upland shrubby habitats. Our results show that local increases of nutrient inputs directly changed the vegetation physiognomy, and indirectly the composition and abundance of bird assemblages.  相似文献   

13.
The elemental composition of otoliths from juvenile English sole Pleuronectes vetulus and speckled sanddab Citharichthys stigmaeus living in estuaries and sandy coastal habitats were compared to determine if a chemical habitat tag existed that could be used to differentiate fish living in the alternative juvenile habitats. Juveniles of both species were collected from seven estuaries and 11 coastal sites along 500 km of the central California coast. Collections occurred in three years: 1998, 1999 and 2000. The chemical composition of the otoliths was analyzed using solution-based inductively coupled plasma mass spectrometry. The multi-elemental composition (Sr, Li, Ba, Mn) of otoliths from estuarine and coastal fish differed significantly for all models (global, region and years models) examined in this study. For each species, discriminant function analysis (DFA) for the global model, which pooled juveniles collected from three regions over multiple years, classified fish into estuarine and coastal groups with close to 80% accuracy. The two main elements in the discriminant models, Sr and Li, differed consistently between habitats; Sr was higher and Li was lower in estuarine fish. Classification success was modestly improved by generating separate discriminant functions for each region (regions model) because of some regional differences in Sr and Li concentrations. Classification success also was improved in some cases by generating separate discriminant functions for each year (years model) because Ba and Mn differed between habitats in only some years. Despite this variability in the concentration of elements in some regions and years, a chemical habitat tag was present in each species that could be used to discriminate coastal and estuarine juveniles over a large geographic area and over three years with very different oceanographic conditions (e.g., El Niño, La Niña). In addition, I found that English sole and speckled sanddab had striking similarities in their chemical habitat tags and that, in some cases, one species could be used as a proxy to classify juveniles of the other species without compromising the accuracy of the habitat tag. The ability to use a proxy classification model would significantly reduce the number of juvenile fish that would need to be collected and analyzed in order to classify members of an ecologically similar species. The chemical habitat tags found in this study appears to be promising tools for identifying fish that have lived in alternative juvenile habitats and, ultimately, the proportional contribution of estuarine and coastal habitats to the central California populations of English sole and speckled sanddab.  相似文献   

14.
Connectivity is a critical property of marine populations, particularly for species with segregated juvenile and adult habitats. Knowledge of this link is fundamental in understanding population structure and dynamics. Young adults of commercially important fish species Solea solea, Solea senegalensis, Platichthys flesus, Diplodus vulgaris and Dicentrarchus labrax were sampled off the Portuguese coast in order to establish preliminary evidence of estuarine nursery origins through otolith elemental fingerprints. Concentrations of Li, Na, Mg, K, Mn, Cu, Zn, Sr, Ba and Pb in the otolith section corresponding to juvenile's nursery life period were determined through laser ablation inductively coupled plasma mass spectrometry. Element: Ca ratios in coastal fish differed significantly amongst collection areas, except for Platichthys flesus, and were compared with the elemental fingerprints previously defined for age 0 juveniles in the main estuarine nurseries of the Portuguese coast. Identification of nursery estuaries was achieved for four of the species. Assigned nursery origins varied amongst species and differences in the spatial scale of fish dispersal were also found. Diplodus vulgaris was not reliably assigned to any of the defined nurseries. Overall, results give evidence of the applicability of estuarine habitat tags in future assessments of estuarine nursery role. Research developments on the links between juvenile and adult habitats should contribute for the integrated management and conservation of nurseries and coastal stocks.  相似文献   

15.
Survival and growth of early fish stages are maximal in coastal and estuarine habitats where natural shallow areas serve as nurseries for a variety of widely distributed species on the continental shelf. Processes occurring in these nursery grounds during the juvenile stage affect growth and may be important in regulating the year-class strength of fishes and population size. The need, therefore, exists to protect these essential fish habitats hence to develop indicators to estimate their quality.The purpose of the present study was to use the growth of juvenile sole as a means of comparing the quality of coastal and estuarine nursery habitats in the Bay of Biscay (France). These sole nurseries were clearly identified from studies based on trawl surveys carried out during the last two decades. The size of 1-group juveniles at the end of their second summer, as estimated from these surveys, is an indicator of growth in these habitats during the juvenile phase and can be used to compare habitat quality. A model taking into account the role of seawater temperature in spatial and interannual variations of juvenile size was developed to compare growth performance in the different nursery sectors.This study shows that the size of juvenile sole after two summers of life is not density-dependent, probably because the size of the population adapts to habitat capacity after high mortality during early-juvenile stages. Size is on one hand positively related to temperature and on the other hand higher in estuarine than in non-estuarine habitats. This high growth potential of juvenile fish in estuarine areas confirms the very important role played by estuaries as nursery grounds and the essential ecological interest of these limited areas in spite of their low water quality. If a general conclusion on habitat quality is to be reached about studies based on the growth of juvenile fish, it is necessary to use not only an integrative indicator of growth, like size, representative of the intrinsic habitat quality, but also more sensitive and less integrative means, such as otolith increments or caging experiments, which better respond to anthropogenic disturbance. Moreover, it is necessary to take juvenile densities into account.  相似文献   

16.
Coastal and estuarine systems provide nursery grounds for many marine fish species. Their productivity has been correlated with terrigeneous inputs entering the coastal–estuarine benthic food web, thereby favouring the establishment of fish juveniles. Studies in these ecosystems often describe the nursery as a single large habitat without verifying nor considering the presence of contiguous habitats. Our study aimed at identifying different habitats based on macrozoobenthic communities and morpho-sedimentary characteristics and assessing the trophic interactions between fish juveniles and their benthic preys within these habitats. It included 43 sampling sites covering 5 habitats in which we described taxonomically and quantitatively the invertebrates and fish communities with stable isotopes and gut contents. It suggested that the benthic common sole Solea solea displayed feeding plasticity at the population level, separating the juveniles (G0) from the older fish (G1) into different “feeding sub-populations”. Size-based feeding plasticity was also observable in the spatial occupancy of that species in the studied bay. The demersal pouting, Trisopterus luscus, equally used the different habitats but displayed low feeding plasticity across and inside each habitat. Stable isotopes proved to be powerful tools to study the spatial distribution of trophic interactions in complex ecosystems like the bay of Vilaine and to define optimal habitats for fish that use the coastal–estuarine ecosystem as nursery grounds.  相似文献   

17.
Marine biodiversity conservation is a common issue in the world. Due to rapid economic development in coastal area in China, marine biodiversity conservation faces great pressure. In this paper, the idea of the integrated coastal zone management (ICZM) was applied as a framework in marine biodiversity conservation. At first, the relationship between integrated coastal zone management and the marine biodiversity conservation was discussed. Then, as a case study in Fujian Quanzhou bay, a set of strategies on marine biodiversity conservation based on ICZM were put forward, which included how to define management boundary of marine biodiversity conservation, the impact assessment model of human activities in the coastal area on marine biodiversity, the planning and management of marine biodiversity conservation, and the monitoring system of the marine biodiversity. Finally, the framework of the comprehensive decision support system based on GIS was suggested.  相似文献   

18.
长江口大型工程对河口生境破碎化影响的初步研究   总被引:2,自引:0,他引:2  
通过对工程海域26个站位的调查采样,研究分析了长江口深水航道治理一期工程对河口生境破碎化的影响。结果表明,工程已对长江河口区局部海域水体和底栖生境破碎化产生了明显影响,而对工程海域小尺度海洋水团、底栖生境和渔业资源生境的破碎化影响最大,造成局部小尺度海洋水团改变,部分渔业资源种类洄游通道、产卵场、肥育场、渔场生境破碎化。建议建立长江口生态特别保护区,加强对河口大型工程综合影响研究与生态修复,加强河口生态系统管理与执法力度,为长江口沿岸城市社会经济的可持续健康发展提供良好的海洋生态环境基础。  相似文献   

19.
江苏盐城自然保护区核心区环境动态的遥感分析   总被引:1,自引:1,他引:1  
冯志轩  罗贤  高抒 《海洋通报》2007,26(6):68-74
根据江苏盐城自然保护区核心区两个时相陆地卫星影像资料的分析和对比,研究了 10 a 内核心区的植被演替、人工开发及潮沟系统演化,探讨自然及人为因素对整个原生湿地生态系统的影响.分析结果表明,互花米草滩的面积 10 a 间扩展了 10 倍以上,而作为珍禽的主要栖息地的盐蒿滩、草滩和芦苇滩的面积 10 a 内均有所下降,其中草滩面积的下降尤为明显.10 a 间芦苇田和水禽湖这两种人工湿地的面积增长显著.潮沟系统呈减少和萎缩趋势,在一定程度上是海岸开发活动和互花米草盐沼扩展的结果.保护区核心区的原生生态系统已有退化迹象,珍禽的原生栖息地的面积有所下降,因此建议保护区将工作重点放在保护和重建原生湿地上.  相似文献   

20.
基于MIKE21模型系统对滨海近岸海洋动力环境进行模拟分析,并根据实测水文数据对模型进行可靠性验证。采用MIKE 21/3 SA溢油分析模块搭建溢油风险数值模型,综合滨海近岸的特殊生态环境分布概况,在溢油高发区组合了8种特定的溢油情景,对近岸主要环境敏感目标在72小时内的受污染情况进行预测分析。结果显示,溢油污染对盐城珍禽保护区、岸线、重要经济鱼类"三场一通道"、海水养殖区以及海域旅游区均存在一定的影响,其中珍禽保护区和岸线受影响最大,"三场一通道"次之,海水养殖区和旅游区最小。滨海珍禽保护区北区和南区最早受影响的时间分别为第16、30h;沿海岸线、"三场一通道"、海水养殖区及海域旅游区最早受影响的时间分别为第20、35、18、28h。  相似文献   

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