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Trophic Assessment in Chinese coastal systems-review of methods and application to the Changjiang (Yangtze) Estuary and Jiaozhou Bay 总被引：3，自引：0，他引：3
Yongjin Xiao João G. Ferreira Suzanne B. Bricker João P. Nunes Mingyuan Zhu Xuelei Zhang 《Estuaries and Coasts》2007,30(6):901-918
Coastal eutrophication has become one of the main threats to Chinese coastal areas during the last two decades. High nutrient
loads from human activities have modified the natural background water quality in coastal water bodies, resulting in a range
of undesirable effects. There is a need to assess the eutrophic level in coastal systems and to identify the extent of this
impact to guide development of appropriate management efforts. Traditional Chinese assessment methods are discussed and compared
with other currently-used methods, such as the Oslo-Paris Convention for the Protection of the North Sea (OSPAR) Comprehensive
Procedure and Assessment of Estuarine Trophic Status (ASSETS). The ASSETS method and two Chinese methods were tested on two
Chinese systems: the Changjiang (Yangtze) Estuary and Jiaozhou Bay. ASSETS is process based, and uses a pressure-state-response
model based on three main indices: Influencing Factors, Overall Eutrophic Condition, and Future Outlook. The traditional methods
are based on a nutrient index. ASSETS was successfully applied to both systems, classifying the Changjiang Estuary as Bad
(high eutrophication) and Jiaozhou Bay as High (low eutrophication). The traditional methods led to ambiguous results, particularly
for Jiaozhou Bay, due to the high spatial variability of data and a failure to assess the role of shellfish aquaculture in
nutrient control. An overview of the Chinese coastal zone identifies 50 estuaries and bays that should form part of a national
assessment. A comparison of methods and results suggests that ASSETS is a promising tool for evaluating the eutrophication
status of these systems. 相似文献
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A.K.TULOKHONOV 《资源与生态学报(英文版)》2011,(3):280-282
The considerable part of the Northern Asia is occupied with the steppe and forest-steppe landscapes stretched by a wide strip from Caspian Sea to mountains of Big Khingan.Archeologists claim, that from here on the Bering Bridge after a glacial age ancestors of American Indian tribes have left to the North America. In the Baikal Lake basin we find settlements of ancient Huns, subdued the Eastern and Western Europe in the beginning of last millennium. 相似文献
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Overview of integrative tools and methods in assessing ecological integrity in estuarine and coastal systems worldwide 总被引：9，自引：1，他引：8
Borja A Bricker SB Dauer DM Demetriades NT Ferreira JG Forbes AT Hutchings P Jia X Kenchington R Carlos Marques J Zhu C 《Marine pollution bulletin》2008,56(9):1519-1537
In recent years, several sets of legislation worldwide (Oceans Act in USA, Australia or Canada; Water Framework Directive or Marine Strategy in Europe, National Water Act in South Africa, etc.) have been developed in order to address ecological quality or integrity, within estuarine and coastal systems. Most such legislation seeks to define quality in an integrative way, by using several biological elements, together with physico-chemical and pollution elements. Such an approach allows assessment of ecological status at the ecosystem level ('ecosystem approach' or 'holistic approach' methodologies), rather than at species level (e.g. mussel biomonitoring or Mussel Watch) or just at chemical level (i.e. quality objectives) alone. Increasing attention has been paid to the development of tools for different physico-chemical or biological (phytoplankton, zooplankton, benthos, algae, phanerogams, fishes) elements of the ecosystems. However, few methodologies integrate all the elements into a single evaluation of a water body. The need for such integrative tools to assess ecosystem quality is very important, both from a scientific and stakeholder point of view. Politicians and managers need information from simple and pragmatic, but scientifically sound methodologies, in order to show to society the evolution of a zone (estuary, coastal area, etc.), taking into account human pressures or recovery processes. These approaches include: (i) multidisciplinarity, inherent in the teams involved in their implementation; (ii) integration of biotic and abiotic factors; (iii) accurate and validated methods in determining ecological integrity; and (iv) adequate indicators to follow the evolution of the monitored ecosystems. While some countries increasingly use the establishment of marine parks to conserve marine biodiversity and ecological integrity, there is awareness (e.g. in Australia) that conservation and management of marine ecosystems cannot be restricted to Marine Protected Areas but must include areas outside such reserves. This contribution reviews the current situation of integrative ecological assessment worldwide, by presenting several examples from each of the continents: Africa, Asia, Australia, Europe and North America. 相似文献
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S.D.Puntsukova 《东北亚地学研究》2009,(4):194-199
The author studied the issues of the present-day status of forest resources and forest management of the Selenge River Basin on the transboundary territory of the Buryat Republic and Mongolia. It is necessary to establish a good policy for wood cutting of the main and secondary use and reforestation. 相似文献
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Sebastian A. Bader D. J. Nederhoff C. M. Leijnse T. W. B. Bricker J. D. Aarninkhof S. G. J. 《Natural Hazards》2021,109(3):2343-2362
Natural Hazards - As demonstrated by recent tropical cyclone events, including U.S. Hurricanes Harvey, Irma, and Maria (2017), and Florence (2018), the destructive potential of flooding driven by... 相似文献
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At low temperatures, in the presence of an aqueous solution, olivine and orthopyroxene are not stable relative to the hydrous phases brucite, serpentine and talc. Alteration of dunite and peridotite to serpentine or steatite bodies must therefore proceed via non-equilibrium processes. The compositions of natural solutions emanating from dunites and peridotites demonstrate that the dissolution of forsterite and/or enstatite is rapid compared with the precipitation of the hydrous phases; consequently, dissolution of anhydrous minerals controls the chemistry of such solutions. In the presence of an aqueous phase, precipitation of hydrous minerals is the rate-controlling step.Brucite-bearing and -deficient serpentinites alter at low temperature by non-equilibrium processes, as evidenced by the composition of natural solutions from these bodies. The solutions approach equilibrium with the least stable hydrous phase and, as a consequence, are supersaturated with other hydrous phases. Dissolution of the least stable phase is rapid compared to precipitation of other phases, so that the dissolving mineral controls the solution chemistry.Non-equilibrium alteration of anhydrous ultramafic bodies continues until at least one anhydrous phase equilibrates with brucite, chrysotile or talc. The lowest temperature (at a given pressure) at which this happens is defined by the reaction: (Johannes, 1968, Contrib. Mineral. Petrol. 19, 309–315) so that non-equilibrium alteration may occur well into greenschist facies metamorphic conditions. 相似文献
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Overview of eutrophication indicators to assess environmental status within the European Marine Strategy Framework Directive 总被引：1，自引：0，他引：1
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Edward D. Goldberg Vern Hodge Minoru Koide John Griffin Eric Gamble Owen P. Bricker Gerry Matisoff George R. Holdren Ruth Braun 《Geochimica et cosmochimica acta》1978,42(9):1413-1425
Present day anthropogenic fluxes of some heavy metals to central Chesapeake Bay appear to be intermediate to those of the southern California coastal region and those of Narragansett Bay. The natural fluxes, however, are in general higher. On the bases of Pb-210 and Pu-239 + 240 geochronologies and of the time changes in interstitial water compositions, there is a mixing of the upper 30 or so centimeters of the sediments in the mid-Chesapeake Bay area through bioturbation by burrowing mollusks and polychaetes. Coal, coke and charcoal levels reach one percent or more by dry weight in the deposits, primarily as a consequence of coal mining operations. 相似文献