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新陈代谢断裂与大地伦理学的经济主义批判——基于奥尔多·利奥波德《环河》的分析
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作者 王继创 《南京林业大学学报(人文社会科学版)》 2023年第2期62-71,共10页
现代生态学认为,自然生态系统有其内在的物质能量新陈代谢循环规律,健康的土地生态系统有其自我更新能力。奥尔多·利奥波德的《环河》通过讲述现代工业化农业的生产方式和经济运行模式违背土地生态系统的物质能量转换规律,造成土... 现代生态学认为,自然生态系统有其内在的物质能量新陈代谢循环规律,健康的土地生态系统有其自我更新能力。奥尔多·利奥波德的《环河》通过讲述现代工业化农业的生产方式和经济运行模式违背土地生态系统的物质能量转换规律,造成土地生态系统能量流动新陈代谢断裂的生动故事,深刻揭示了土地新陈代谢断裂之“殇”的经济主义根源,提出要进行符合生态学逻辑的价值观变革和现代生态保护意识的培育。生态价值观的确立和生态良知的养成是生态伦理学的必然价值旨归。奥尔多·利奥波德的《环河》代表现代生态环境保护意识的觉醒,具有生态文明时代的伦理启蒙意义。 展开更多
关键词 奥尔多·利奥波德 《环河》 功利主义 生态良知
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Effects of Southward Flow of Yellow River on Eco-environment of Xu-Huai River Basin 被引量:8
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作者 李高金 韩宝平 钱程 《Agricultural Science & Technology》 CAS 2010年第1期15-18,共4页
Based on the historical records,the flood disasters in Xu-Huai River Basin caused by southward flow of Yellow River were studied,while its effects on Xu-Huai regional economic,transportation and eco-environment were a... Based on the historical records,the flood disasters in Xu-Huai River Basin caused by southward flow of Yellow River were studied,while its effects on Xu-Huai regional economic,transportation and eco-environment were also highlighted,and finally historical natural disasters were presented in this study. 展开更多
关键词 Southward flow of Yellow River ECO-ENVIRONMENT Xu-Huai River Basin
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Application of Grey Relational Analysis in Regional Water Environment Assessment——Taking Jin River Basin as An Example 被引量:5
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作者 吴万刚 《Agricultural Science & Technology》 CAS 2015年第4期850-852,共3页
According to the data from four water monitoring stations at Meihewan, Shimawan, Tanwan and Jinbin, the water environment at the downstream basin of Jin River was evaluated through grey reIational analysis in this stu... According to the data from four water monitoring stations at Meihewan, Shimawan, Tanwan and Jinbin, the water environment at the downstream basin of Jin River was evaluated through grey reIational analysis in this study. The resuIts showed that the water environment was severeIy contaminated by phosphorus, am-monia nitrogen and permanganate. 展开更多
关键词 Grey relatlonal analysis Water environment Jin River
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Countermeasures for Treatment in Water Environment of Nanfeihe River
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作者 张彦辉 朱慧娈 +2 位作者 吴蕾 黄志 匡武 《Agricultural Science & Technology》 CAS 2016年第11期2519-2524,共6页
According to current situation of the severe water pollution and bad water environment of Nanfeihe River catchment, the major environment problems were id- entified based on the investigation and analysis of the gener... According to current situation of the severe water pollution and bad water environment of Nanfeihe River catchment, the major environment problems were id- entified based on the investigation and analysis of the general situation of the catch- ment, the present situation of water quality and water volume composition, corre- sponding countermeasures were put forward to provide a reliable theoretical support for controlling pollution in water environment of Nanfeihe River. 展开更多
关键词 Nanfeihe River Water environment COUNTERMEASURES
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On the Regional Ecological Planning of the Ancient Yellow River Course in Shangqiu City 被引量:2
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作者 田颖 李亚光 蒋航 《Journal of Landscape Research》 2010年第3期35-39,共5页
This paper analyzed the problems of eco-environment along the ancient Yellow River course and, by combining with the planning scheme of ecological projects of the ancient Yellow River course in Shangqiu City, discusse... This paper analyzed the problems of eco-environment along the ancient Yellow River course and, by combining with the planning scheme of ecological projects of the ancient Yellow River course in Shangqiu City, discussed its ecological planning ways in terms of the principles, objectives, methods and contents of the ecological planning and design to promote the regional eco-environment construction of the ancient Yellow River course. 展开更多
关键词 Ancient Yellow River Course Ecological environment Ecological planning Environmental restoration
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The dry-hot valleys and forestation in southwest china 被引量:6
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作者 马焕成 Jack A.McConchie 《Journal of Forestry Research》 CAS CSCD 2001年第1期35-39,共7页
The dry-hot valleys (DHV) are located mainly in the deeply incised v alleys along the upper streams of several international and domestically rivers, like Yangtz, Zhu, Lanchang, Hong, and Nu rivers. This paper briefl... The dry-hot valleys (DHV) are located mainly in the deeply incised v alleys along the upper streams of several international and domestically rivers, like Yangtz, Zhu, Lanchang, Hong, and Nu rivers. This paper briefly described t he reasons of formation of DHV from view of climate and geographical conditions, and by referring to great deal of documents, analyzed the historical case and p resent status of the vegetations in DHV. The environment in DHV is facing the se rious vulnerable period in the history due to its nature situation of half-year dry period, fragile geological structure and shallow soil, and its social situat ion of over dense population and over farming. The primary vegetation is broad l eaf forest and it was denuded in the history. The current local vegetation is th e degraded secondary vegetation: savanna and succulent thorny shrub. Since the e nvironmental situation in valley influenced directly the water body of river, th e soil erosion control and re-vegetation in DHV is the most urgent task in the p rocess of environmental harness along the rivers. Quite a few pilot research pro jects have been carried out.on demonstrating new silviculture techniques for re- vegetation in DHV, but there still exist great difficulties in carrying out larg e-scale afforestation engineering. 展开更多
关键词 Dry-hot valley Forestation Environmental harness
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Ecological Environment Problems and Countermeasures of Small and Middle-sized Rivers in Shandong Province
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作者 赵维军 彭淑贞 +3 位作者 燕婷婷 张伟 张莹 宋晓鹏 《Agricultural Science & Technology》 CAS 2016年第10期2369-2372,共4页
Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and co... Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and concluded existing problems. Finally, ecological treatments were proposed based on treatments at home and abroad in order to improve eco-environment of rivers and build better Shandong. 展开更多
关键词 ECO-ENVIRONMENT Small and middle-sized rivers Problems and Countermeasures Shandong Province
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Distribution and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Mussels from the Middle and Lower Main Stream of Huaihe River
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作者 赵彩平 丁毅 +1 位作者 叶云 李玉成 《Agricultural Science & Technology》 CAS 2009年第6期101-104,149,共5页
[ Object] The aim was to discuss the pollution status of polycyclic aromatic hydrocarbons (PAHs) in mussels from the middle and lower main stream of Huaihe River, which will provide a scientific basis for dietary sa... [ Object] The aim was to discuss the pollution status of polycyclic aromatic hydrocarbons (PAHs) in mussels from the middle and lower main stream of Huaihe River, which will provide a scientific basis for dietary safety of mussels. [ Method] Suspended matter, sediment, and mussel samples were collected from Wuxiaojie and Fushanji in middle and lower reaches of Huaihe River. All samples were extracted with Soxhlet, separated through Silica GeI-Al2O3 column, and determined by GC-MS, and then 16 typical PAHs contents in the prior table listed by American EPA were obtained. [ Result] The results indicated that total PAHs concentrations in suspended matters and sediments of Wuxiaojie were significantly higher than those in Fushanji respectively. However, PAHs concentrations in mussels of the two samplings showed little difference; as for single PAH component, low-ring PAHs were more advantaged in suspended matters of two sampling sites, while high-ring PAHs were more advantaged in mussels. PAHs in sediments of Wuxiaojie assumed low-ring aspect, though PAHs in sediments of Fushanji assumed high-ring aspect. [ Conclusion] In spite of that sediments and mussels were not yet contaminated according to the ecological risk assessment of PAHs, its potential hazards couldn't be ignored any more. 展开更多
关键词 Huaihe River Mussels Polycyclic aromatic hydrocarbons (PAHs) Risk elevation
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Coordinated Development of Human Settlement and Economy in County-level Cities in the Yellow River Basin
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作者 朱效明 李旭祥 张静 《Journal of Landscape Research》 2010年第3期95-99,共5页
[Objective] To provide quantification means for comprehensively analyzing the coordinated development of urban human settlement and economy by constructing an index system of economy and human settlement. [Method] By ... [Objective] To provide quantification means for comprehensively analyzing the coordinated development of urban human settlement and economy by constructing an index system of economy and human settlement. [Method] By constructing an evaluation index system of economy and human settlement, and using the coordinate measurement model of them, 22 county-level cities in the Yellow River Basin were analyzed. [Result] In the Yellow River Basin, the construction level of economy and human settlement in those county-level cities is low with distinct spatial differences and deteriorating polarization; there is a great spatial corresponding between coordinated development degree and economic level, the higher the economic development level, the higher coordinated development degree in county-level cities; county-level cities around the boundaries of provinces have difficulties in development. [Conclusion] Evaluation standards and models are clear in significance, convenient in application, which can successfully evaluate the coordination of human settlement development in the study region. 展开更多
关键词 County-level city economy Human settlement COORDINATION Yellow River Basin
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Spatial and environmental effects on plant communities in the Yellow River Delta, Eastern China 被引量:8
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作者 宋创业 刘高焕 刘庆生 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期117-122,I0002,共7页
Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distributi... Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling methods. Results showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix chinensis. The vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble potassium. Among the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total variation. Spatial variation and spatial-structured environmental variation explain 11.8%, and 2.2%, respectively. Remained 40.8% of undetermined variation is attributed to biological and stochastic factors. 展开更多
关键词 detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis
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The environment effect on fish assemblage structure in waters adjacent to the Changjiang(Yangtze) River estuary(1998-2001) 被引量:21
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作者 于海成 线薇微 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期443-456,共14页
We collected fish abundance data in the Changjiang(Yangtze River) estuary and adjacent waters in November 1998,May 1999,November 2000,and May 2001.Using the data,we evaluated the characteristics of the fish assemblage... We collected fish abundance data in the Changjiang(Yangtze River) estuary and adjacent waters in November 1998,May 1999,November 2000,and May 2001.Using the data,we evaluated the characteristics of the fish assemblages at each site and investigated the effect of several environmental factors.We used a multivariate analysis,including community ordination methods such as detrended correspondence analysis(DCA) and canonical correspondence analysis(CCA),and two-way indicator species analysis(TWINSPAN).We analyzed the biological community structure and environmental factors to determine their spatial distributions,temporal dynamics,and seasonal variations.Among the fish species,five exceeded 5% of the total abundance:Harpodon nehereus(42.82%),Benthosema pterotum(13.85%),Setipinna taty(11.64%),Thryssa kammalensis(9.17%) and Apogonichthys lineatus(6.49%).These were separated into four ecological assemblages:hypsithermal-saline,hypsithermal-brackish,hypothermal-brackish,and hypothermal-saline.We evaluated the degree of influence of environmental factors on the fish community.Our analyses suggested that environmental factors including water depth,salinity,turbidity,transparency,nutrient,and suspended matter formed a synthetic spatial gradient between the coastal and pelagic areas.Ecological and environmental factors changed temporally from 1998 to 2001,and drove the fish community succession.The environmental factors driving the fish community structure included bottom temperature,water depth,bottom and surface pH,surface total phosphorous,and bottom dissolved oxygen.This investigation was completed before completion of the Three Gorges Dam;therefore the results of this study provide an important foundation for evaluating the influence of the human activities. 展开更多
关键词 fish assemblage structure environmental factors multivariate analysis Changjiang (Yangtze River) estuary
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Coordination of Urbanization and Water Ecological Environment in Shayinghe River Basin,China 被引量:7
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作者 ZHANG Xiang HU Hong +1 位作者 XU Jiangang YIN Haiwei 《Chinese Geographical Science》 SCIE CSCD 2011年第4期476-495,共20页
During the rapid industrialization and urbanization of China,urban agglomeration in river basin areas raises the problems of over-use of water resources and pollution of the water environment.Related research in China... During the rapid industrialization and urbanization of China,urban agglomeration in river basin areas raises the problems of over-use of water resources and pollution of the water environment.Related research in China has mainly focused on the conflicts among economic growth,urban expansion and water resource shortages within admin-istrative boundaries.However,water environments are much more dependent on their physical boundaries than their administrative boundaries.Consistent with the nature of water environment,this study aims at analyzing coordination relationships between urban development and water environment changes within physical river basin boundaries.We chose the Shayinghe River Basin,China,as our case study area which is facing serious challenges related to water en-vironment protection.Then we classified 35 county-level administrative units into upstream,midstream and down-stream regions based on their physical characteristics;analyzed the coordination degree of urban agglomeration using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method;and constructed cooperative models using the Linear Programming (LP function) to simulate four scenarios of the coordination relationship be-tween urban population increase and water environment protection based on existing water resources and water pollu-tion data.The results show that the present coordinative situation in Shayinghe River Basin is not sustainable.In gen-eral,more than 50% administrative units are in the bad coordinative situation.In particular,the downstream region is under worse condition than the upstream and midstream regions.Cooperative models in scenario analyses indicate that the population scale set in existing urban master plannings is not coordinated with the water environment protection.To reach the goal of regional sustainable development,the total population needs to be controlled such that it will re-main at 4.5×10 7 or below by 2020 given the capacity of water environment. 展开更多
关键词 water ecological environment coordination analysis cooperative model urban agglomeration Shayinghe River Basin
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Partitioning of grain-size components of estuarine sediments and implications for sediment transport in southwestern Laizhou Bay, China 被引量:13
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作者 陈广泉 易亮 +4 位作者 陈沈良 黄海军 刘艳霞 徐勇航 曹建荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期895-906,共12页
Sediment transport in estuarine systems has been of increasing interest for scientists during the past few decades. However, the mechanisms for sediment redistribution remain unclear. We characterized in detail sedime... Sediment transport in estuarine systems has been of increasing interest for scientists during the past few decades. However, the mechanisms for sediment redistribution remain unclear. We characterized in detail sediment transport in the Xiaoqing River estuary using the mathematical Weibull function to partition grain-size components of surface sediments in the southwestern Laizhou Bay, Northeast China. Four partitioned components: finer than 4,4.6-12.5, 23.4-63.3, and 67.1-132.6 μm were interpreted in terms of hydrodynamic conditions. During sediment transport, silt grains were suspended and moved seaward from three depositional centers, whereas fine-grained sands moved generally landward. Overall, sediments are transported clockwise in a generally NNE direction near shore and then turn eastward offshore. The mathematical partitioning method showed a great potential for future estuarine environmental studies. 展开更多
关键词 sediment transport estuarine environment sediment grain size mathematical partitioning Laizhou Bay (China)
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Assessment of dam impacts on river flow regimes and water quality:a case study of the Huai River Basin in P.R.China 被引量:2
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作者 夏军 张永勇 《Journal of Chongqing University》 CAS 2008年第4期261-276,共16页
The Huai River Basin is a unique area in P.R.China with the highest densities of population and water projects.It is also subject to the most serious water pollution.We proposed a distributional SWAT(Soil and Water As... The Huai River Basin is a unique area in P.R.China with the highest densities of population and water projects.It is also subject to the most serious water pollution.We proposed a distributional SWAT(Soil and Water Assessment Tool) model coupled with a water quality-quantity balance model to evaluate dam impacts on river flow regimes and water quality in the middle and upper reaches of the Huai River Basin.We calibrated and validated the SWAT model with data from 29 selected cross-sections in four typical years(1971,1981,1991 and 1999) and used scenario analysis to compensate for the unavailability of historical data regarding uninterrupted river flows before dam and floodgate construction,a problem of prediction for ungauged basins.The results indicate that dam and floodgate operations tended to reduce runoff,decrease peak value and shift peaking time.The contribution of water projects to river water quality deterioration in the concerned river system was between 0 to 40%,while pollutant discharge contributed to 60% to 100% of the water pollution.Pollution control should therefore be the key to the water quality rehabilitation in the Huai River Basin. 展开更多
关键词 DAMS river control river basin projects prediction in ungauged basins flow regime water environment Huai River Basin
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SEFIDROOD RIVER SUB-WATERSHED-DAM-ESTUARY AND DEGRADATION MODEL:A HOLISTIC APPROACH IN IRAN 被引量:1
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作者 Forood AZARI DEHKORDI Majid F MAKHDOUM Nobukazu NAKAGOSHI 《Chinese Geographical Science》 SCIE CSCD 2003年第4期328-333,共6页
The major concern of this article is to address the shortcoming and outgoing effects of the human activities on the landscape patterns and their consequences in the Sefidrood River watershed in Iran. A flow of data in... The major concern of this article is to address the shortcoming and outgoing effects of the human activities on the landscape patterns and their consequences in the Sefidrood River watershed in Iran. A flow of data includes three inputs; each of them belongs to one part of three zones of a fluvial system. The three parts of the Sefidrood River fluvial system include Zone 1,a sub-watershed as degradation modeling site,Zone 2,Sefidrood Dam as dam site,and Zone 3,17km away from the Sefidrood River path to the Caspian Sea as ending point site. The degradation model in the Zone 1 provides a suitable mean for decision support system to decrease the human impacts on each small district. The maximum number for degradation coefficient belongs to the small district with the highest physiographic density,relatively cumulative activities,and a lower figure for the habitat vulnerability. The human degradation impact were not limited to the upstream. The investigation to the Sefidrood Dam and ending point of the Sefidrood River depicts that sedimentation continues as a significant visual impact in the Sefidrood Dam reservoir and the estuary. 展开更多
关键词 degradation modeling sefidrood river watershed sefidrood dam iran
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Simulation of coupled pelagic-benthic ecosystem of the Yellow Sea Cold Water Mass 被引量:2
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作者 万小芳 吴增茂 +1 位作者 张志南 李杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第4期393-399,共7页
A one-dimensional coupled pelagic-benthic box model for the Yellow Sea Cold Water Mass (YSCWM) is developed. The model is divided into three boxes vertically according to the depths of thermocline and euphotic layer. ... A one-dimensional coupled pelagic-benthic box model for the Yellow Sea Cold Water Mass (YSCWM) is developed. The model is divided into three boxes vertically according to the depths of thermocline and euphotic layer. It simulates well the oligotrophic shelf ecosystem of the YSCWM considering effects of nu- trients deposition and microbial loop. Main features of vertical structure of various variables in ecosystem of the YSCWM were captured and seasonal variability of the ecosystem was well reconstructed. Calculation shows that the contribution of microbial loop to the zooplankton can reach up to 60%. Besides, input of inorganic nutrients from atmospheric deposition is an important mechanism of production in upper layer of the YSCWM when stratified. 展开更多
关键词 coupled pelagic-benthic ecosystem the Yellow Sea Cold Water Mass seasonal variability oligotrophic shelf ecosystem
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Chemical and spectroscopic characterization of dissolved humic substances in a mangrove-fringed estuary in the eastern coast of Hainan Island,China 被引量:7
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作者 张耀玲 杜金洲 +3 位作者 彭浡 张芬芬 赵欣 张经 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期454-463,共10页
Mangrove-derived dissolved organic matter (DOM) has an important effect on estuarine and coastal area on a large scale. In order to improve the understanding of origin, composition, and fate of DOM in mangrove-fring... Mangrove-derived dissolved organic matter (DOM) has an important effect on estuarine and coastal area on a large scale. In order to improve the understanding of origin, composition, and fate of DOM in mangrove-fringed estuarine and coastal areas, dissolved humic substances (DHS) were isolated from one mangrove pore-water sample and one near-shore seawater sample downstream the mangrove pore-water site in the eastern coast of Hainan Island, South China. Fulvic acids, humic acids and XAD-4 fractions were obtained from the two water samples by using a two-column array of XAD-g and XAD-4 resins. Chemica~ and spectroscopic methods were used to analyze the features of these DHS. Compared to the mangrove pore-water DHS, the near-shore seawater DHS were found rich in 13C with lower C/N ratios and more aliphatic compounds and carbohydrates, but less aromatic structures and carboxyl groups. As for the three fractions of the two DHS, XAD-4 fractions contain more aliphatics, carbohydrates, carboxyl groups, and enrich in 13C with respect to both fulvic and humic acids. Photo-oxidation transformation and contribution from marine-derived DOM were considered as the main reasons resulted in the difference in compositional features for these DHS in this study. 展开更多
关键词 MANGROVE fulvic acid humic acid XAD-4 fraction FTIR NMR
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Determination of a Reasonable Percentage for Ecological Water-Use in the Haihe River Basin, China 被引量:6
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作者 XIA Jun FENG Hua-Li +1 位作者 ZHAN Che-Sheng NIU Cun-Wen 《Pedosphere》 SCIE CAS CSCD 2006年第1期33-42,共10页
An investigation was conducted to study problems of determining a reasonable percentage for ecological water-use in the Haihe River Basin of China. Three key aspects for the ecological water requirement (EWR) were a... An investigation was conducted to study problems of determining a reasonable percentage for ecological water-use in the Haihe River Basin of China. Three key aspects for the ecological water requirement (EWR) were analyzed, involving i) the EWR for river system, ii) the EWR for wetlands and lakes, and iii) the EWR for discharge into the sea to maintain the estuary ecological balance of the Haihe River. The Montana method and related water level-flow relationships, and the statistic approach based on hydrological records were applied to estimate different components of EWR. The results showed that the total ecological water demand in the region, was about 3.47-14.56 billion m^3. Considering flow regime change and uncertainty, the ecological water demand could be estimated by the hydrological frequency approach. Preliminary analysis showed that for different annual runoff under the frequencies of 20%, 50%, 75% and 95%, the ecological water demand approached 12%-50%, 18%-74%, 24%-103%, 35%-148% and 16%-66%, respectively. By further analysis to balance ecological water-use and socioeconomic water-use, the rational percentage of ecological water-use was estimated as 35%-74%, that provides useful information to judge whether the allocation of water resources is reasonable, and was proved to be satisfactory by comparing with the practical condition. 展开更多
关键词 ecological water requirement ecological water-use Haihe River Basin
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Nitrogen Biological Cycle Characteristics of Seepweed(Suaeda salsa) Wetland in Intertidal Zone of Huanghe(Yellow) River Estuary 被引量:10
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作者 SUN Zhigao MOU Xiaojie +6 位作者 SUN Jingkuan SONG Hongli YU Xiang WANG Lingling JIANG Huanhuan SUN Wanlong SUN Wenguang 《Chinese Geographical Science》 SCIE CSCD 2012年第1期15-28,共14页
From April 2008 to November 2009, the nitrogen (N) cycle of plant-soil system in seepweed (Suaeda salsa) wetland in the intertidal zone of the Huanghe (Yellow) River estuary was studied. Results showed that soil... From April 2008 to November 2009, the nitrogen (N) cycle of plant-soil system in seepweed (Suaeda salsa) wetland in the intertidal zone of the Huanghe (Yellow) River estuary was studied. Results showed that soil N had sig- nificant seasonal fluctuations and vertical distribution, and the net N mineralization rates in topsoil were significantly different in growing season (p 〈 0.01). The N/P ratio (9.87 ±1.23) of S. salsa was less than 14, indicating that plant growth was limited by N. The N accumulated in S. salsa litter at all times during decomposition, which was ascribed to the N immobilization by microbes from the environment. Soil organic N was the main N stock of plant-soil system, accounting for 97.35% of the total N stock. The N absorption and utilization coefficients of S. salsa were very low (0.0145 and 0.3844, respectively), while the N cycle coefficient was high (0.7108). The results of the N turnovers among compartments of S. salsa wetland showed that the N uptake amount of aboveground part and root were 7.764 g/m2and 4.332 g/m2, respectively. The N translocation amounts from aboveground part to root and from root to soil were 3.881 g/m2 and 0.626 g/m2, respectively. The N translocation amount from aboveground living body to litter was 3.883 g/m2, the annual N return amount from litter to soil was more than 0.125(-) g/m2 (minus represented immobili- zation), and the net N mineralization amount in topsoil (0-15 cm) in growing season was 1.190 g/m2. The assessment of N biological cycle status orS. salsa wetland indicated that N was a very important limiting factor and the ecosystem was situated in unstable and vulnerable status. The S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the N quantitative relationships determined in the compartment model might provide scientific base for us to reveal the special adaptive strategy orS. salsa to the vulnerable habitat in the following studies. 展开更多
关键词 NITROGEN biological cycle seepweed wetland Huanghe (Yellow) River estuary
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ANALYSIS OF HABITAT PATTERN CHANGE OF RED-CROWNED CRANES IN THE LIAO HE DELTA USING SPATIAL DIVERSITY INDEX 被引量:3
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作者 WANGLing LIXiu-zhen +1 位作者 HUYuan-man GUODu-fa 《Chinese Geographical Science》 SCIE CSCD 2003年第2期164-170,共7页
Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. Th... Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands. 展开更多
关键词 spatial diversity Index red-crowned crane ( GrUS japonensis) habitatpattern the liaohe delta
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