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91.
胶州湾湿地海域水体和表层沉积物环境质量评价   总被引:2,自引:0,他引:2  
基于2009年对胶州湾湿地48个站点的调查数据,采用内梅罗(Nemerow)指数、富营养指数(EI)和Hakanson潜在生态危害指数法对胶州湾湿地水体和表层沉积物环境质量现状进行了评价.结果表明:对参与评价的pH值、溶解氧、无机氮、活性磷酸盐、CODMn、石油类、Cu、Zn、Pb、Cd、Hg、As、六六六、滴滴涕、大肠菌群、粪大肠菌群等16项指标而言,各调查月份大沽河感潮河段水质处于中污染-重污染水平,潮间带区域水质处于轻污染-中污染水平,浅海区域水质处于轻污染水平.胶州湾湿地不同区域富营养化程度差异明显,其中大沽河感潮河段水体EI值在58.13 ~327.89,富营养化程度严重;潮间带区域水体EI值在1.34 ~19.96,富营养化程度较为严重;浅海区域水体EI值在0.65 ~ 2.10,富营养化程度较轻.胶州湾湿地海域表层沉积物质量基本处于轻污染水平,其中大沽河感潮河段处于轻污染水平,潮间带区域处于轻污染-中污染水平,浅海区域处于较清洁-轻污染水平.胶州湾湿地海域表层沉积物中重金属单项污染参数(Cfi)和污染程度指数(Cd)较低,污染程度处于低级水平,Cu、Zn是表层沉积物中的主要污染因子;重金属潜在的生态危害系数(Eir)和潜在生态危害指数(RI)较小,污染程度属于低生态危害范畴.  相似文献   
92.
Zhou J  Chen B  Yu W W  Huang H 《农业工程》2011,31(5):264-270
Coastal wetland is located in the active interface between land and sea, which is one of the richest biodiversity habitats, while it is seriously disturbed and destroyed by anthropogenic activities in both terrestrial and marine parts. Habitat serves as the basis for organism survival, providing food, shelter, water, space and so on, and habitat degradation and loss caused by intense anthropogenic activities is widely considered as the main reason for biodiversity decline and loss. However, there is still limited study on the evaluating methods of coastal wetland habitats, especially for those in a large scale. In this study, methods for evaluating coastal wetland habitat quality, including selecting indicators, setting value assignment criteria and weights were discussed systematically, a method of coastal wetland habitat quality evaluation was established, and the habitat quality in Quanzhou Bay was also evaluated as a case study. The present study provided a new concept and method to assess quantitatively habitat status, indicate the ecological status and its change, and also reflect and predict indirectly the ecological impact of human activities.
Referring to the habitat evaluation system (HES) developed by United States in the mid 1970s, the evaluation method was established by thorough analysis of the characteristics of coastal wetland. The habitat indicators were selected in terms of three habitat factors as follows: chemical factors, including dissolved oxygen (DO), phosphate in seawater, sulfide in sediment, and regional priority pollutants; physical factors, including landscape naturalness index and coastline artificialization index; biological factors, including invasive species risk and area ratio of invasive alien species. Weights were established by Analytic Hierarchy Process, combined with several-round expert evaluation. Evaluation criteria providing principles for value assignment of each indicator, were established referring to previous standards and related researches. The final result for assessing habitat quality was indicated and stated by the value of Habitat Quality Index (HQI), which is the weighted sum of each indicator. Habitat quality increased with the HQI value, with value ranging from 0 to 100.
The established evaluating method was applied to assess the habitat quality of Quanzhou Bay, located in the southeast coastal zone of Fujian Province, with a total area of 136.4 km2, which is an important bay in Fujian. Quanzhou Bay wetland is a typical coastal wetland with diverse wetland habitats, including mangrove, estuary, island, aquaculture ponds, salt pan, shallow sea, mud flat and so on. The Quanzhou Bay is now seriously suffering environmental problems, e.g. eutrophication due to great discharge of domestic, agricultural and industrial wastewater, rapid urbanization and reclamation resulting in decreased wetland area, and the invasion of alien species. The evaluation results showed that the habitat quality index value was 68.13, 57.99 and 51.23 in 1989, 2002 and 2008, respectively, indicating that the habitat degraded gradually. The five major factors that led to decline of HQI value were phosphate in seawater, lead in sediment, landscape naturalness index and coastline artificialization index and area ratio of invasive alien species. Therefore, in order to improve and maintain habitat quality, it is urgent to control pollution, large-scale reclamation and Spartina invasion in Quzhou Bay.  相似文献   
93.
94.
In order to evaluate the usefulness of a biomonitoring system using seaweeds for assessing the geographic distribution of metal ions in coastal seawaters, the metal concentrations in the sporophytes of an annual kelp, Undaria pinnatifida (Harvey) Suringar, were collected at 15 localities in Osaka Bay, Japan and compared. About 160 cm2 of the blade was cut out from the central part of clean sporophytes, rinsed in filtered seawater using an ultrasonic cleaning bath, and freeze‐dried. After digestion with 12% HNO3 in a microwave apparatus, metal concentrations in the samples were determined by inductively coupled plasma mass spectrometry. The concentrations (dry weight basis) of most examined elements were in the parts per million range; Cr, 0.48–3.18; Ni, 0.77–5.94; Cu, 3.20–43.8; Zn, 11.3–86.8; Pb, 0.14–3.53. Comparisons of metal compositions of the U. pinnatifida samples from the northeastern area of the bay, which has a large urban population and highly developed industries inland, showed high concentrations of Cd, Pb and Cu compared with the samples from the southwestern area of the bay where the population and industries are much smaller. This suggests that U. pinnatifida metal loads can be used as a marker to track the geographic distributions of the metal concentrations in coastal seawaters, reflecting inland human activities such as shipbuilding and repairing in port areas, and can be used as a useful biomonitoring system of coastal environments for long‐term trend.  相似文献   
95.
The Pawcatuck river watershed (797 km2) is located in southern Rhode Island and northeastern Connecticut. The predominant lithology of the area is granite, and over 60% of the watershed remains forested with mixed hardwoods (primarily oak) and eastern white pine. As part of a larger study of nutrient and sediment exports from the watershed to Little Narragansett Bay, we measured dissolved silica (SiO2) (DSi) concentrations at the river mouth over 70 times between January 14, 2002 and November 29, 2002. Annual export of DSi during our study was 40 × 106 mol or 50 kmol km−2. The United States Geological Survey (USGS) obtained DSi concentrations at this site, at varying frequencies, from 1978 to the present, which allowed for a historical comparison of this study with previous years. River DSi concentrations exhibited a strong seasonal signal that did not vary in a regular way with water discharge or water temperature. DSi and dissolved inorganic nitrogen (DIN) concentrations were significantly related over the annual cycle (p<0.0001) and both decreased substantially during the spring. Dissolved inorganic phosphorus (DIP) did not covary at any time with silica or nitrogen, suggesting that in-stream biological uptake was not responsible for the seasonal decline in silica. The spring decline in river silica concentrations may be due to silica uptake by terrestrial vegetation. We estimate a net forest silica accretion rate of 41 kmol km−2 y−1, a value that is stoichiometrically consistent with other measurements of net carbon accretion in nearby forests.  相似文献   
96.
Several investigations exist which use planktonic communities as indicators of water quality in Jamaican and Caribbean Bays, however, few are conducted before there are obvious effects of eutrophication. Therefore, most of our ‘baseline’ data are for bays already severely affected by pollution. This study was conducted to assess water quality in Discovery Bay, Jamaica, before there were severe signs of eutrophication. The bay was monitored over a 12-month period (October 1995–September 1996) using 10 stations. Physicochemical data indicated a well mixed upper 5 m of water column, below which discontinuities in temperature/salinity profiles indicated the influence of colder, more saline waters associated with deep offshore currents. Physicochemical variables were within the range for oligotrophic systems with a tendency towards mesotrophic in localized areas close to the shoreline. Signs of anthropogenic stress were associated with the eastern, southwestern and western sections of the bay. Of the over 120 species of phytoplankton found in the waters of Discovery Bay, most were neritic/oceanic and diatoms dominated while 11 were found to be potentially harmful species. While these harmful species occurred at all stations they occurred most frequently at stations on the eastern side of the bay. About 107 zooplankton species were identified, 52 of which were copepods. The species also represented a mix of neritic and oceanic taxa and mean abundances for the area ranged from 1077 m−3 at the mouth of the bay to 3794 m−3 close to the south shore (station 6). Generally stations closest to shore had greater zooplankton abundances than centrally located bay stations and stations close to oceanic influence. Acartia tonsa and Lucifer faxoni showed greatest densities at shoreline areas of the bay while Oithona plumifera, Undinula vulgaris and Temora stylifera were important at stations closest to oceanic influences. These species were thus considered as indicators of these different areas within the bay. From physicochemical data and the planktonic assemblage, Discovery Bay cannot be considered polluted, it is still more accurately classified as generally pristine with mesotrophic zones in the eastern and southeastern sections of the bay. These data therefore provide a real baseline of conditions for similar tropical coastal embayments.  相似文献   
97.
First discovered in San Francisco Bay in 1992, the Chinese mitten crab,Eriocheir sinensis, has become established over hundreds of km2 of the San Francisco Estuary. Ecological and economic impacts of this invasive species motivated our search for a greater understanding of the crabs life history as an important step in better management and control. Data for this life history model comes from the authors research and scientific literature. Juvenile crabs migrate from the Estuary into fresh water where they develop into adults. Environmental signals may stimulate gonad development that is followed by a downstream migration beginning at the end of summer. Mating occurs after the crabs reach saline water. Embryos are carried until hatching, and the larvae undergo five zoeal stages before settlement. Our model projects rates of development at various temperatures and growth increments, supports a minimum of 2 years in low salinity or freshwater habitat, and predicts that most California mitten crabs are at least 3 years old before becoming sexually mature. Environmental factors strongly influence the timing and duration of the crabs life stages, and are discussed in the context of a gradient of development times for worldwide populations of this important invasive species.  相似文献   
98.
The objective of this study was to determine the expression, distribution in the column, and overall frequency of sagittal clefting of the vertebral body in the skeletons of two Canadian Inuit groups. One group, referred to as Thule-Historic, lived along the coast northwest of Hudson Bay, while the other, known as the Sadlermiut, were limited to Southampton Island and Coats Island north of Hudson Bay. The Thule-Historic people are thought to be the ancestors of the present-day Inuit of this region, whereas the much smaller, relatively isolated Sadlermiut became extinct during the winter of 1902-1903. The sagittal clefting results were also compared with those obtained for two other vertebral developmental problems, segmentation error and spina bifida. Sagittal clefting was found to occur with high frequency in the two Inuit series, especially in the region T6-T10. Segmentation errors were found to occur in approximately the same region of the column, while spina bifida produced a completely different pattern, occurring primarily at T11 and S1. The T11 involvement is limited to females, while S1 involvement occurs primarily in males. Sagittal clefting and spina bifida occur in the same individual more frequently than sagittal clefting and segmentation error. Possibly reflecting the smaller population size and isolated location of the Sadlermiut, sagittal clefting was found with greater frequency and intensity in the skeletons of this group than in those of the Thule-Historic Inuit. Am J Phys Anthropol, 2003.  相似文献   
99.
遥感技术在大亚湾区域土地利用类型监测中的应用   总被引:2,自引:0,他引:2  
何章莉  史合印  邢前国  潘伟斌 《生态科学》2006,25(4):371-374,384
文章综合利用了Landsat系列卫星不同传感器(MSS、TM、ETM )的遥感资料对1979至2004年20多年间的大亚湾周边的植被陆地、非植被陆地以及水域等土地利用类型的相关变化进行了定量监测与评估。遥感监测结果表明,在过去的二十多年间,大亚湾周边植被覆盖总体保持相对稳定,但非植被陆地由1991年的5.1%左右上升到2004年的10.5%左右,水体面积也相应降低了5%左右,表现出“人进水退”的总体变化格局,该变化特征与该区域过去的环境政策、经济活动发展历程有关。通过将人类对区域环境影响的方式、力度和土地利用类型的变化建立一种对应关系,可以预测以后的开发建设活动对土地利用类型的影响,并应用到区域环境影响评价中去。  相似文献   
100.
Yu H Y  Li B Q  Wang J B  Wang H F 《农业工程》2006,26(2):416-422
The current situation of the animal species biodiversity of macrobenthic fauna in the Jiaozhou Bay (South Shandong Peninsula, Yellow Sea) is reported in the present paper, based on the data from 15 investigation cruises carried out from February 1998 to November 2001. In analyzing the data, the Shannon-Wiener index, and species evenness and richness indices were used to study the trends of variation of the community structure, the species assemblages in the macrobenthic community, the dominant species, and the abundance of macrobenthic fauna in Jiaozhou Bay. A total of 322 species of macrobenthic animals were found in the bay, of which 133 species belong to 44 families of Polychaeta, while 92 species belong to 42 families of Crustacea. The average number of species per sample station ranged from 8 to 26. The Shannon-Wiener indices were very different among the samples, with the highest being recorded from Station 8 in November 2001, and the lowest from Station 9 in August 2001. The number of species, the Shannon-Wiener indices, and the species richness indices from Stations 7 and 9 were generally lower than those from other stations. This is because both the stations are situated at areas with a strong current and where the sediment is coarse sand. Although the richness index of species and the Shannon-Wiener index were high in Station 3, the Pielou evenness index was the lowest of all the sampling stations. This is because the station is located near the culture area of Ruditapes philippinarum, where a high abundance of clams caused low evenness. The results also revealed that the number of species and abundance greatly affected the biodiversity, and some environmental factors such as temperature, salinity, and primary productivity were also closely interrelated with biodiversity. Pollution and overexploitation caused by human activities were very important factors affecting macrobenthic biodiversity. In order to find the best way to enhance and protect living marine resources, the relationship between human activities and the biodiversity of macrobenthos in the Jiaozhou Bay should be studied further.  相似文献   
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