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61.
莲花山白盆珠湿地生态恢复   总被引:1,自引:0,他引:1  
莲花山白盆珠湿地为广东省重点湿地,是中国南亚热带内陆性湿地的典型类型。结合莲花山白盆珠湿地保护建设工程,运用生态修复理念,提出相应实施措施,在实现湿地恢复、环境整治的同时,促使其形成循环的湿地生态系统,实现湿地的可持续发展。  相似文献   
62.
Living (Rose Bengal stained) benthic foraminifera were investigated at 18 deep-sea stations sampled in the Whittard Canyon area (NE Atlantic). The stations were positioned along 4 bathymetric transects ranging from 300 to 3000 m depth: two along the main canyon axes (Western and Eastern branches) and two along adjacent open slopes (Western and Eastern slopes). The aim of this study was to assess changes of foraminiferal standing stock, composition and microhabitat in relation to the physico-chemical conditions prevailing at and below the sediment-water interface in various canyon and open-slope environments. Minimal oxygen penetration depths and maximal diffusive oxygen uptakes were recorded at upper canyon stations, suggesting a high mineralisation rate. This is confirmed by the high phytopigment concentrations measured in the sediment of the upper canyon axes. Foraminiferal abundance was positively correlated with diffusive oxygen uptake and phytopigment concentration in the sediment. This suggests a control of organic matter fluxes on the foraminiferal communities. Foraminiferal abundance was generally higher along the canyon axis compared to open-slope sites at comparable water depths. The species composition varied with water depth along all four transects, but was also different between canyon branches and adjacent slopes. The silty/sandy intercalations at many of the deeper canyon stations may have been rapidly deposited by fairly recent gravity flows. At station 51WB (3002 m), the faunal characteristics (strong dominance, shallow infaunal microhabitats) suggest that the foraminiferal community is in an early state of ecosystem colonisation after these recent sedimentation events, which would have supplied the important amounts of phytopigments.  相似文献   
63.
The State of Kansas, as an energy-producing and agriculture-based state, faces problems in production of natural resources and potential pollution from their production. To coordinate information on the exploration, production, and use of coal, nuclear, petroleum, natural gas, hydro, wind, geothermal, coalbed methane, biofuel, solar, and other energy resources, the Kansas Energy Council and the University of Kansas Energy Research Center were created. Water, surface and subsurface, is the other important and maybe the most important natural resource in the welfare of the state. To ease the problems of contamination, situations are monitored by regulatory agencies: the Kansas Corporation Commission, Kansas Department of Health and Environment, and Division of Water Resources of the Kansas Department of Agriculture. The Kansas Geological Survey (KGS) at the University of Kansas serves as the archive for energy and natural resource data and conducts research pertinent to the exploration and exploitation of mineral resources, including energy and water. The Kansas Energy Research Center coordinates and supports energy activities. The Kansas Water Office and the staff for the Kansas Water Authority are charged with water planning and preparing reports on water problems and possible solutions. The cost of preserving the environment in a relatively pristine state really is of no concern considering the possible consequences; living conditions should be preserved to assure future generations, a suitable, sustainable, stable environment. With all the dire predictions for the future and energy-producing and pollution problems, Kansas is a model state in this modern industrial age for protecting the environment and is a leader in conservation.
Daniel F. MerriamEmail:
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64.
Martin J. Haigh 《Area》2002,34(3):242-252
Deep Ecology provides a complete and practical philosophy to guide practice, research and teaching in physical geography. This proposes that long–term human self–interest is served best by serving the needs of Nature, which also provides an agenda for research. Understanding is constructed in three steps from the realization of the internal self, through the social self and ultimately the ecological Self, which provides an agenda for teaching and learning. Being 'useful' is proposed as a duty for geography. Its first priorities should be environmental management, mitigating the ecological footprint of humanity: first for the benefit of society, but ultimately for the benefit of the Self – within Nature. Systems thinking should guide investigation because Deep Ecology conceives Nature as a single interacting, multidimensional whole.  相似文献   
65.
Diatoms from the genus Achnanthidium are abundant in rivers, streams, and springs of the Appalachian Mountains. They inhabit clean and polluted waters, including those affected by acid mine drainage. The identification of Achnanthidium taxa is difficult due to their small cell size and insufficient information in the diatom floras. We studied the taxonomy and ecology of Achnanthidium in Appalachian rivers by analyzing a data set of benthic diatom samples and corresponding water chemistry data collected during several water-quality surveys from 181 sampling sites. Ten species were identified using scanning electron and light microscopy: A. alpestre (Lowe & Kociolek) Lowe & Kociolek, A. atomus (Hustedt) Monnier, Lange-Bertalot, & Ector, A. deflexum (Reimer) Kingston, A. duthii (Sreenivasa) Edlund, A. eutrophilum (Lange-Bertalot) Lange-Bertalot, A. cf. gracillimum (Meister) Lange-Bertalot, A. cf. latecephalum Kobayasi, A. minutissimum (Kützing) Czarnecki (sensu lato), A. reimeri (Camburn) comb. nov., and A. rivulare Potapova & Ponader. The distribution of common taxa in relation to water chemistry was studied by fitting non-parametric regression models (generalized additive models, GAM, and non-parametric multiplicative regression models, NPMR) to species relative abundances. Studied Achnanthidium species differed considerably in their responses to water chemistry. These results suggest that species-level identifications will lead to more accurate bioassessments.  相似文献   
66.
Seasonal occurrence of six ostracod species (Psychrodromus olivaceus, Potamocypris villosa, Ilyocypris inermis, Candona candida, Candona neglecta, and Cypridopsis vidua) varied from May 2003 to June 2004 in three types of spring (Limnocrene, Helocrene, Rheocrene). When I. inermis was only found in the limnocrene spring each month, P. olivaceus was common in all types of springs. The other four ostracods were found in the helocrene spring in fall, winter, and spring seasons. The unweighted pair group mean averages dendrogram separated three main clusters. The first cluster includes two species (C. vidua, C. candida) while I. inermis was found in the second cluster and P. olivaceus, C. neglecta, and P. villosa were found in the third. The occurrence of P. olivaceus and C. neglecta and P. villosa and C. candida was strongly correlated to each other (r=0.750 and 0.850, respectively). The Pearson correlation analyses showed a strong negative relationship between C. neglecta and water temperature (r=−0.607), but other species did not show any significant correlation to any of the environmental variables used (P>0.05). Canonical correspondence analyses (CCA) displayed all species closer to the center of the dendrogram, indicating high levels of species tolerances to environmental variables. Thus, the first axis of the CCA diagram explained 80% of the relationship between six species and five environmental variables.  相似文献   
67.
Since sewage treatment plants are most effective in Switzerland, the micro-benthic communities in receiving running waters have changed considerably. From January 1980 to September 1981 the periphyton communities in 13 Swiss streams and rivers were monthly investigated. The NH4-N concentration in these waters varied between 0.015 and 1.0 mg/l. Four typical communities of microorganisms were found:In unpolluted running waters mainly small vagile ciliates were abundant; in slightly polluted waters peritricha (in the presence of bacteria) were found; in moderatly polluted waters peritricha in combination of few hymenostomata and Sphaerotilus could grow when bacteria and some degredable organic material where present; in polluted waters the well-known Spaerotilus-community (after Liebmann) could be found.The microscopic as well as the macroscopic aspect should be considered to qualify the degree of pollution in streams and rivers.  相似文献   
68.
Integrating toxicology and ecology: putting the "eco" into ecotoxicology   总被引:1,自引:0,他引:1  
Environmental toxicology has been and continues to be an important discipline (e.g., single-species testing for screening purposes). However, ecological toxicology (ecotoxicology--more realism in tests, test species and exposures) is required for predicting real world effects and for site-specific assessments. Ecotoxicology and ecology have shown similar developmental patterns over time; closer cooperation between ecologists and toxicologists would benefit both disciplines. Ecology can be incorporated into toxicology either extrinsically (separately, e.g., providing information on pre-selected test species) or intrinsically (e.g., as part of test species selection)--the latter is preferable. General guidelines for acute and chronic testing and criteria for species selection differ for ecotoxicology and environmental toxicology, and are outlined. An overall framework is proposed based on ecological risk assessment (ERA), for combining ecology and toxicology (environmental and ecological) for decision-making. Increased emphasis on ecotoxicology represents a shift from reductionist to holistic approaches.  相似文献   
69.
This paper explores the 12 aspects of geo-environment and construction engineering, including the earth evolution, the structure of geological bodies, the comprehensive utilization of resources, the geo-environmental effect, the engineering construction, the sustainable development and, etc. This paper presents that the good environment could only be created through the conservation and efficient utilization of resources, the joint efforts of disaster prevention and mitigation, as well as the avoidance of adverse environmental effect caused by human activities. This paper concludes that, to build a scientific and ecological earth, the development laws of geo-science must be learnt.  相似文献   
70.
Mapping and measuring the ecological embeddedness of food supply chains   总被引:1,自引:0,他引:1  
Marianne Penker 《Geoforum》2006,37(3):368-379
The status of nature in food systems is the subject of this paper, which looks into the ecological embeddedness of the Austrian food system both on the national level and in a regional case study. By a first attempt to measure and map ecological embeddedness, the author intends to contribute to the operationalisation of the embeddedness concept, which is characterised as ambivalent, fuzzy and dynamic (see e.g., [Goodman, D., 2003. The quality ‘turn’ and alternative food practices: reflections and agenda. Editorial. Journal of Rural Studies 19 (1), 1-7; Markusen, A., 1999. Fuzzy concepts, scanty evidence, policy distance: the case for rigour and policy relevance in critical regional studies. Regional Studies 33, 869-884; Hess, M., 2004. ‘Spatial’ relationships? Towards a reconceptualization of embeddedness. Progress in Human Geography 28 (2), 165-186]). The paper starts with a critical outline of the academic discourse on embeddedness in food chain studies. In the second section, general developments in the Austrian food system and their ecological implications are illustrated for the national level. Thereafter in a case study, the author tries to map and measure the ecological embeddedness of two conventional bread chains. The focus on conventional food chains provides a contrast with the growing body of embeddedness studies concentrating on alternative food chains. The author concludes that for both conventional as well as alternative food chains, the mode of ecological embeddedness or the degree of a food chain’s commitment to particular landscapes could become important factors for the maintenance, enhancement and capture of ecological value.  相似文献   
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