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井矿盐企高质量发展策略与路径探析
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作者 陈之然 席洋 《盐科学与化工》 CAS 2024年第4期1-4,共4页
高质量发展是我国经济进入新时代后的客观要求,是贯彻落实创新、协调、绿色、开放、共享的新发展理念,促进企业经营由规模型向价值型转变,协同推进,提质增效。文章基于井矿盐企高质量发展的背景分析,界定其高质量发展内涵,提出四维高质... 高质量发展是我国经济进入新时代后的客观要求,是贯彻落实创新、协调、绿色、开放、共享的新发展理念,促进企业经营由规模型向价值型转变,协同推进,提质增效。文章基于井矿盐企高质量发展的背景分析,界定其高质量发展内涵,提出四维高质量发展策略体系,即“创新驱动、品牌引领、延链发展、人才兴企”,并从“业务生态、创新研发、精准营销、智慧协同、人才队伍建设”五个方面对其实施路径进行探析。 展开更多
关键词 井矿 +生态 高质量发展 发展策略与路径
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塔里木河流域干旱区人工绿洲灌区生态水权及其计量研究 被引量:3
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作者 孙建光 韩桂兰 《生态经济》 CSSCI 北大核心 2014年第6期183-186,共4页
对流域干旱区人工绿洲灌区生态水权进行内涵界定,并确定其计量依据与内容和计量方法与模型。基于塔河流域绿洲城市、防护林和盐碱耕地及其灌水定额等相关资料,利用城市生态水权、防护林生态水权和洗盐生态水权计量模型,以及人工绿洲... 对流域干旱区人工绿洲灌区生态水权进行内涵界定,并确定其计量依据与内容和计量方法与模型。基于塔河流域绿洲城市、防护林和盐碱耕地及其灌水定额等相关资料,利用城市生态水权、防护林生态水权和洗盐生态水权计量模型,以及人工绿洲灌区生态水权计量模型,得出塔河流域干旱区人工绿洲灌区生态水权的计量结果为:塔河流域人工绿洲灌区生态水权为15.666×10^8 m^3,其中叶尔羌河流域5.161×10^8 m^3,阿克苏河流域5.454×10^8 m^3,和田河流域3.899×10^8 m^3,塔河干流上游0.352×10^8 m^3,干流中游0.312×10^8 m^3,干流下游0.490×10^8 m^3;年内分配以6月~9月和3月~5月为主,占93.52%。而且流域人工绿洲灌区生态水权以源流为主,其中洗盐生态水权占43.72%,防护林生态水权占55.92%,城市生态水权占0.36%,今后人工绿洲灌区生态水权分配需要重点考虑防护林生态水权和洗盐生态水权。 展开更多
关键词 塔里木河流域 干旱区人工绿洲 灌区生态水权 生态水权
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盐生荒漠生态系统二氧化碳通量的年内、年际变异特征 被引量:25
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作者 刘冉 李彦 +2 位作者 王勤学 许皓 郑新军 《中国沙漠》 CSCD 北大核心 2011年第1期108-114,共7页
采用涡度相关法,并结合小气候观测,对荒漠生态系统净二氧化碳通量进行了连续3个生长季的观测(2004—2006年),并据此分析了荒漠生态系统净二氧化碳通量及其主要成分GPP和Reco的季节和年际间变化特征。结果表明,在生长季尺度上,各个阶段... 采用涡度相关法,并结合小气候观测,对荒漠生态系统净二氧化碳通量进行了连续3个生长季的观测(2004—2006年),并据此分析了荒漠生态系统净二氧化碳通量及其主要成分GPP和Reco的季节和年际间变化特征。结果表明,在生长季尺度上,各个阶段二氧化碳吸收量的大小分别为:生长旺盛期>生长初期>生长末期,这可能与植物叶面积的大小以及光合有效辐射,大气温度等环境要素有关系。在年际尺度上,3个生长季同阶段的二氧化碳吸收量存在明显差异,生长季初期5月,2004年碳吸收最强,2006年次之,2005年最小。对于生长旺盛期,降水量最大的2004年碳吸收能力最强,正午最大值可以达到-0.12 mg.m-2.s-1,2005年次之,最大值达-0.06 mg.m-2.s-1,仅仅是2004年最大值的1/2,2006年最小,正午吸收的最大值为-0.02 mg.m-2.s-1,生长季末期,3个生长季的月均日变化非常相似,其在正午的最大吸收值也没有显著差异,正午最大吸收量为-0.01mg.m-2.s-1左右,其他时段均在0值附近。即使在降水量相近的两个年份里(2005—2006年),其NEE的最大值出现时间也不一致,2005年NEE的最大月累计量出现在8月和9月,而2006年则出现在6月和7月,这可能与年内降水量分布格局有关。3个生长季荒漠生态系统均表现为净二氧化碳吸收,其吸收量分别为:-236.18g.m-2,-63.07 g.m-2和-91.97 g.m-2。年际差异的形成原因是降水差异造成的一年生草本植物数量变化,不利用降水的建群种应该对此没有贡献。 展开更多
关键词 二氧化碳通量 生荒漠生态系统 涡度相关技术 生态系统呼吸
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Eco-geochemical Characteristics of Muskmelon Root Soil in Planting Region of Hetao Irrigation Area of Inner Mongolia
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作者 侯俊琳 《Agricultural Science & Technology》 CAS 2016年第9期2147-2151,共5页
[Objective] The aim was to evaluate the eco-geochemical characteristics and geochemistry conditions of root soil in muskmelon planting area, evaluate the soil environment quality in Hetao irrigation area and provide s... [Objective] The aim was to evaluate the eco-geochemical characteristics and geochemistry conditions of root soil in muskmelon planting area, evaluate the soil environment quality in Hetao irrigation area and provide scientific basis for the musmelon planting in this area. [Method] Root system soil sample and plow pan sample were collected from the main muskmelon planting area in Hetao irrigation area, so as to analyze the contents of heavy metal elements. By comparing with the Soft Environmental Quality Standard (GB15618-1995), the research explored whether the heavy metal elements in root system met the national standard. [Result] Heavy metal elements in root system soil had the maximum content in recession area of Yellow River, followed by saline soils. The content of heavy metal elements in chestnut-brown soil was the minimum. Harmful elements As, Cd, Hg, F and Pb in anthropogenic-alluvial soil of Hetao irrigation area showed enrichment characteristics in earth surface, with zonality vertically. Trace elements Cu and Zn, and beneficial elements P, K20, CaO, MgO and Se showed depletion. In anthropogenic-aUuvial soil of Ulansuhai of the Yellow River, harmful elements As and Cd showed significant enrichment in root system soil, while other elements showed depletion or was close to background value. In soil of plow pan, both beneficial component and harmful component showed enrichment characteristics. [Conclusion] Hetao irrigation area has the ideal geochemical conditions and heavy metal elements in muskmelon area meet the national standards. 展开更多
关键词 Root system soil Anthropogenic-alluvial soil Saline soil Eco-geochemical characteristics
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Application Research of Restoration Materials on Degraded Land 被引量:3
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作者 胡慧慧 崔艳杰 +3 位作者 薛合伦 陈兰 孔秋婵 梁玉祥 《Agricultural Science & Technology》 CAS 2011年第9期1260-1264,1302,共6页
[Objective] The paper aimed at researching on the ecological remediation materials and related technologies in degraded land.[Method] Pointing at the specific reasons for degradation of soil moisture and fertility con... [Objective] The paper aimed at researching on the ecological remediation materials and related technologies in degraded land.[Method] Pointing at the specific reasons for degradation of soil moisture and fertility conditions,the ecological remediation materials and related technologies for soil moisture had been studied using layered silicates as substrate materials and using straw turnover as the method.The application research had been carried out in degraded cultivated land,compacted land,saline-alkali soil and laboratory of nine provinces and regions on 26 species and 48 varieties.[Result] The materials and related technologies are environment-friendly in formula,processing,application with no hidden trouble as secondary pollution,which can be used for the restoration of positive balance of soil moisture conditions(water,fertilizer,gas,and heat),establishment of the core of a stable circle and improving food production steadily.The materials are more suitable for plant growth than chemical fertilizers,applying of which helps plants obtain better adversity resistance.[Conclusion] The ecological remediation materials for soil moisture can reduce the application of chemical fertilizers effectively and improve the production and quality of crops remarkably. 展开更多
关键词 Land degradation Saline-alkali land Ecological restoration Ecological agriculture
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Saline Water Irrigation Scheduling Through a Crop-Water-Salinity Production Function and a Soil-Water-Salinity Dynamic Model 被引量:16
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作者 WANG Yang-Ren KANG Shao-Zhong +2 位作者 LI Fu-Sheng ZHANG Lu ZHANG Jian-Hua 《Pedosphere》 SCIE CAS CSCD 2007年第3期303-317,共15页
Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to o... Using a crop-water-salinity production function and a soil-water-salinity dynamic model, optimal irrigation scheduling was developed to maximize net return per irrigated area. Plot and field experiments were used to obtain the crop water sensitivity index, the salinity sensitivity index, and other parameters. Using data collected during 35 years to calculate the 10-day mean precipitation and evaporation, the variation in soil salinity concentrations and in the yields of winter wheat and cotton were simulated for 49 irrigation scheduling that were combined from 7 irrigation schemes over 3 irrigation dates and 7 salinity concentrations of saline irrigation water (fresh water and 6 levels of saline water). Comparison of predicted results with irrigation data obtained from a large area of the field showed that the model was valid and reliable. Based on the analysis of the investment cost of the irrigation that employed deep tube wells or shallow tube wells, a saline water irrigation schedule and a corresponding strategy for groundwater development and utilization were proposed. For wheat or cotton, if the salinity concentration was higher than 7.0 g L-1 in groundwater, irrigation was needed with only fresh water; if about 5.0 g L-1, irrigation was required twice with fresh water and once with saline water; and if not higher than 3.0 g L-1, irrigation could be solely with saline water. 展开更多
关键词 crop-water-salinity production function irrigation scheduling saline water irrigation water-salinity dy- namic model
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Influence of Temperature and Salinity on Germination of Eelgrass (Zostera marina L.) Seeds 被引量:7
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作者 PAN Jinhua JIANG Xin +7 位作者 LI Xiaojie CONG Yizhou ZHANG Zhuangzhi LI Zhiling ZHOU Weili HAN Houwei LUO Shiju YANG Guanpin 《Journal of Ocean University of China》 SCIE CAS 2011年第2期147-152,共6页
Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has bee... Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination rate of eelgrass (Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24℃) and nine salinities (5 to 45, increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA) (P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14℃ and salinity 5. Higher temperature significantly increased the germination rate at salinity 5 (P<0.001) during the whole observation period except for 24℃, while lower salinity significantly increased the germination rate at 14℃ (P<0.001). Although significant interaction was found between temperature and salinity (P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results provide useful information for the propagation of artificial seedlings for seagrass restoration in China. 展开更多
关键词 EELGRASS Zostera marina L. seed germination TEMPERATURE SALINITY
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EXAMINATION OF SILICATE LIMITATION OF PRIMARY PRODUCTION IN JIAOZHOU BAY, CHINA I. SILICATE BEING A LIMITING FACTOR OF PHYTOPLANKTON PRIMARY PRODUCTION 被引量:31
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作者 杨东方 张经 +2 位作者 吕吉斌 高振会 陈豫 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期208-225,共18页
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations i... Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO - 3 N, NO - 2 N, NH + 4 N, SiO 2- 3 Si, PO 3- 4 P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq.(1) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C , the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D , the coefficient of water temperature’s effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant nutrient concentrations but low phytoplankton biomass in some waters is reasonably explained in this paper. 展开更多
关键词 PHYTOPLANKTON silicon limiting factor Jiaozhou Bay
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Impacts of Aquaculture and Domestic Wastewater on the Water Quality of Santubong River, Malaysia 被引量:2
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作者 T.Y. Ling C.M. Michelle +2 位作者 L. Nyanti I. Norhadi J.J.E. Justin 《Journal of Environmental Science and Engineering》 2010年第4期11-16,共6页
Developments along the Santubong River basin may have an impact on the aquatic ecosystem. To determine the impacts of activities on the water quality, ten stations were selected for water quality study over 9 months. ... Developments along the Santubong River basin may have an impact on the aquatic ecosystem. To determine the impacts of activities on the water quality, ten stations were selected for water quality study over 9 months. Results show that salinity increases from 14.0 PSU upstream to 30.4 PSU downstream. Lowest DO range was 2.3-4.1 mg/L. TSS ranged was 20-135 mg/L and the highest was observed near construction and residential areas, the second and third highest near shrimp culture discharge areas. BOD5 was the highest near construction and residential areas. BOD5 of a station near shrimp culture was not significantly different from the residential areas. Two stations near shrimp culture site also recorded the highest Chl-a. The highest ammonia-nitrogen, nitrite-nitrogen and reactive phosphorus were observed at stations near shrimp farm sites whereas nitrate-nitrogen was the highest near construction and residential areas. Cage culture site showed the highest phosphorus and second highest nitrite-nitrogen and ammonia-nitrogen. This study showed that TSS and BOD5 were elevated near residential and construction areas and nutrients were elevated near shrimp farm sites resulting in algal bloom. Therefore, it is recommended that residential and shrimp farm discharge be treated to acceptable quality before discharge to protect the aquatic resources. 展开更多
关键词 Shrimp aquaculture household wastewater water quality Santubong River.
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Dynamics of Saline-alkali Land and Its Ecological Regionalization in Western Songnen Plain, China 被引量:18
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作者 YANG Jiuchun ZHANG Shuwen +4 位作者 LI Ying BU Kun ZHANG Yubo CHANG Liping ZHANG Yangzhen 《Chinese Geographical Science》 SCIE CSCD 2010年第2期159-166,共8页
As the important reserve land resources for food production,saline-alkali land should play a significant role to ensure the national food security in the context of global food crisis. The western Songnen Plain is one... As the important reserve land resources for food production,saline-alkali land should play a significant role to ensure the national food security in the context of global food crisis. The western Songnen Plain is one of main distribution regions of saline-alkali land in China,with great potential in agricultural development. In this study,the extent,transformation,spatial distribution and temporal change of saline-alkali land in the western Songnen Plain during 1954–2005 were investigated by using remote sensing and GIS spatial analysis methods. Saline-alkali land change was detected from a temporal series of topographic maps in 1954,satellite images of Landsat MSS in 1976,Landsat TM/ETM in 1988,2000 and 2005 through artificial visual interpretation. The results indicated a significant expansion in saline-alkali land area and aggravation in salinization. The area of saline-alkali land had increased from 401.48×103 ha in 1954 to 1 097.45×103 ha in 2005. While the ratio of light,moderate and serious salinized land areas changed from 6.72︰2.92︰1.00 to 1.25︰1.06︰1.00 in the study period. Grassland,cropland,swampland and water body were the major land use and land cover types from which saline-alkali land transformed. And the secondary salinization occured mainly in Da′an City,Tongyu County,Changling County,Daqing City,Dorbod Mongolian Autonomous County and Zhaoyuan County. Finally,seven large ecoregions and 14 corresponding sub-ecoregions were delineated out based on spatio-temopral dynamic characteristics of saline-alkali land and geo-relational environmental attributes. According to the results,measures of amelioration and ways of development of saline-alkali land in the western Songnen Plain were put forward. 展开更多
关键词 saline-alkali land SALINIZATION ecological regionalization food security Songnen Plain
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CHARACTERIZATION OF LACTATE DEHYDROGENASE ISOZYME PATTERN AND MORPHOLOGY OF THREE MARINE FISH CELL LINES 被引量:1
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作者 郭华荣 张士璀 +2 位作者 李红岩 童裳亮 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期226-231,共6页
Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus ) heart and RSBF (i.e., Red Sea... Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus ) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream ( Pagrosomus major ) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these three cell lines and their corresponding tissues of origin were investigated and compared. The results showed: (1) No difference was found in the LDH isozyme patterns of FG and flounder gill tissue. However, the LDH isozyme patterns of SPH and RSBF were significantly different from their corresponding tissues of origin; (2) LDH isozyme patterns of FG, SPH and RSBF were markedly different from each other and could serve as genetic markers for species identification and detection of cross contamination. Morphological change analysis of these three cell lines in comparison to their original tissues indicated that FG cells still appeared epithelioid without morphological transformation. However, morphological changes were found in SPH and RSBF compared to their original tissues. Therefore, the cellular morphology was still plastic in the relatively stable culture conditions, and it was possible that change of LDH patterns was related to morphological changes of fish cells in vitro . 展开更多
关键词 cell line lactate dehydrogenase cellular morphology FLOUNDER sea perch red sea bream
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Sewage pollution in Negril, Jamaica: effects on nutrition and ecology of coral reef macroalgae 被引量:5
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作者 B. E. LAPOINTE K. THACKER +1 位作者 C. HANSON L. GETTEN 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期775-789,共15页
Coral reefs in the Negril Marine Park (NMP), Jamaica, have been increasingly impacted by nutrient pollution and macroalgal blooms following decades of intensive development as a major tourist destination. A baseline... Coral reefs in the Negril Marine Park (NMP), Jamaica, have been increasingly impacted by nutrient pollution and macroalgal blooms following decades of intensive development as a major tourist destination. A baseline survey of DIN and SRP concentrations, C:N:P and stable nitrogen isotope ratios (δ^15N) of abundant reef macroalgae on shallow and deep reefs of the NMP in 1998 showed strong P-limitation and evidence of increasing sewage pollution. In 1999, a sewage collection and treatment project began diverting wastewater from the resort and urban areas to a pond system that discharged partially-treated effluent into the South Negril River (SNR). These sewage discharges significantly increased concentrations of NH2 and SRP (N:P -13) in the SNR, which flows into Long Bay and around Negril's "West End". Concentrations of SRP, the primary limiting nutrient, were higher on shallow reefs of the West End in 2001 compared to 1998. Stable nitrogen isotope ratios (δ^15N) of abundant reef macroalgae on both shallow and deep reefs of the West End in 2002 were significantly higher than baseline values in 1998, indicating an escalating impact of sewage nitrogen pollution over this timeframe. The increased nutrient concentrations and δ^15N enrichment of reef macroalgae correlated with blooms of the chlorophyte Chaetornorpha linum in shallow waters of Long Bay and Codium isthrnocladum and Caulerpa cupressoides on deep reefs of the West End. Sewage treatment systems adjacent to coral reefs must include nutrient removal to ensure that DIN and SRP concentrations, after dilution, are below the low thresholds noted for these oligotrophic ecosystems. 展开更多
关键词 MACROALGAE SEWAGE carbon NITROGEN PHOSPHORUS stable nitrogen isotopes EUTROPHICATION
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Biogeochemical conversion of sulfur species in saline lakes of Steppe Altai
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作者 BORZENKO Svetlana V. KOLPAKOVA Marina N. +1 位作者 SHVARTSEV Stepan L. ISUPOV Vitaly P. 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期676-686,共11页
The aim of the present research is to identify the main mechanisms of sulfur behavior in saline lakes in the course of time and followed transformations in their chemical composition. The influence of water on chemica... The aim of the present research is to identify the main mechanisms of sulfur behavior in saline lakes in the course of time and followed transformations in their chemical composition. The influence of water on chemical composition of biochemical processes involved in decomposition of organic matter was determined by the study of behavior of reduced forms of sulfur in lakes. The determination of reduced forms of sulfur was carried out by successive transfer of each form of sulfur to hydrogen sulfide followed by photometric measurements. The other chemical components were determined by standard methods(atomic absorption, potentiometric method, titration method and others). The salt lakes of the Altai steppe were studied in summer season 2013–2015. Analysis of the chemical composition of the saline lakes of Altai Krai has shown that carbonate-, hydrocarbonate-and chloride ions dominate among anions; sodium is main cation; sulfates are found in subordinate amounts. Reduced forms of sulfur occur everywhere: hydrogen and hydrosulfide sulfur S^(2-) prevail in the bottom sediments; its derivative—elemental S^0—prevails in the lakes water. The second important species in water of soda lakes is hydrosulfide sulfur S^(2-), and in chloride lakes is thiosulfate sulfur S_2O_2^(3ˉ). The lag in the accumulation of sulfates in soda lakes in comparison to chloride lakes can be explained by their bacterial reduction, followed by the formation and deposition of iron sulfides in sediments. In chloride lakes gypsum is a predominantly barrier for sulfates. 展开更多
关键词 saline lake sulfate reduction gypsum Altai
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Could Acid Sulfate Soils Be a Potential Environmental Threat to Estuarine Ecosystems on the South China Coast? 被引量:4
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作者 C. LIN (School of Geography, The University of New South Wales, Sydney, NSW 2052, Australia) 《Pedosphere》 SCIE CAS CSCD 1999年第1期53-59,共7页
Acid sulfate soils (ASS) contain considerable amounts of reduced sulfur compounds (mainly pyrite) which produce sulfuric acid upon their oxidation. ASS-derived environmental degradation widely occurs in the coastal lo... Acid sulfate soils (ASS) contain considerable amounts of reduced sulfur compounds (mainly pyrite) which produce sulfuric acid upon their oxidation. ASS-derived environmental degradation widely occurs in the coastal lowlands around the world, especially in the tropical and subtropical areas. The presence of ASS in the South China has been recognized but their distribution may be largely underestimated because the soil survey data concerning ASS are based on unreliable methods and techniques. ASS in the South China have been traditionally used for rice cultivation and this practice has been proved sustainable if appropriate improvement measures are adopted. Recently, the rapid economic growth in the region has resulted in intensified coastal development which frequently involves activities that may disturb ASS. Construction of roads, foundations and aquaculture ponds may cause the exposure of ASS to air and bring about severe environmental acidification. There is currently insufficient awareness of the problems among the researchers, policy-makers and land managers in the South China. More atteation must be paid to the possible ASSderived environmental degradation in order to ensure a sustainable development of the coastal lowlands in the South China region. 展开更多
关键词 acid sulfate soils environmental degradation PYRITE
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Analysis of ecological effects of comprehensive treatment in the Tarim River Basin using remote sensing data 被引量:4
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作者 Tan Kelong Wang Xiaofeng Gao Huijun 《Mining Science and Technology》 EI CAS 2011年第4期519-524,共6页
Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel... Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel of the Tarim River Basin.The results of our investigation show that the ecological environment in the Green Corridor of the main channel of the Tarim River Basin has conspicuously improved from 2002 to 2004.These improvements show up largely in such aspects as an increase in the rate of vegetation cover,a reduction in desertification land areas and a weakening in the intensity of sandy and the salinized land.On the other hand,the cultivated area in the Tarim River Basin significantly increased from 2002 to 2004.The rate of growth in cultivated areas during this period was significantly higher than that from 1999 to 2002.The increase in the use of irrigation resulting from the substantial increase in cultivated areas has a long-term potential restraining effect on the restoration of ecological functions of the Tarim River. 展开更多
关键词 Ta-rim River Basin Cultivated land changes Water transportation Ecological effect Remote sensing
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Relationship between Water and Vegetation in the Ejina Delta 被引量:1
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作者 YU Jingjie WANG Ping 《Bulletin of the Chinese Academy of Sciences》 2012年第1期68-75,共8页
Water is the foundation of an arid ecological system, as the quantity and quality of surface water and groundwater determine its structure and function. The study on the relationship between water and ecosystem is the... Water is the foundation of an arid ecological system, as the quantity and quality of surface water and groundwater determine its structure and function. The study on the relationship between water and ecosystem is the basis of ecosystem protection. Taking the Ejina delta, an extremely arid area located downstream of the Heihe River in northwestern China, as an example, this article gives an overviewe of the study in three aspects: (1) the groundwater table and salinity dynamics and their driving factors, (2) the groundwater depth and salt threshold of natural vegetation ecosystem, and (3) the impact evaluation of ecological flow control on Ejina natural vegetation. The authors point out the importance of the research into the relation between water and ecosystem and its key difficulties and weakness, and put forward strategies for promoting the study processes. 展开更多
关键词 Chinese inland river extremely arid region envrionmental flow control natural vegetation groundwater environment
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Long-term ecological interactions between nutrient and phytoplankton community in the Changjiang estuary 被引量:9
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作者 江涛 俞志明 +2 位作者 宋秀贤 曹西华 袁涌铨 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期887-898,共12页
Both nitrate((NO_3)^-) and soluble reactive phosphate((PO_4)^(3-)) concentration in the freshwater end-member at the mouth of the Changjiang River have increased dramatically since the 1960s.Within the same period in ... Both nitrate((NO_3)^-) and soluble reactive phosphate((PO_4)^(3-)) concentration in the freshwater end-member at the mouth of the Changjiang River have increased dramatically since the 1960s.Within the same period in the sea area,with surface salinity>30,(NO_3)^-concentration has shown an obvious increase,(PO_4)^(3-) has not changed greatly and dissolved reactive silica((SiO_3)^(2-)) has deceased dramatically.An examination of the elemental ratio of(NO_3)^-to(PO_4)^(3-) at the mouth of the Changjiang River did not show a systematic trend from the 1960s to 2000s largely because both nutrients increased simultaneously.In comparison,the elemental ratio of dissolved inorganic nitrogen(DIN) to(PO_4)^(3-) in surface seawater,with salinity>22,has shown a clearly increasing trend.Furthermore,an overall historical change of the(SiO_3)^(2-):(PO_4)^(3-) ratio has undergone a reverse trend in this area.Based on the changes of(SiO_3)^(2-):(PO_4)^(3-) and DIN:(PO_4)^(3-) ratios,we can conclude that an overall historical change of(SiO_3)^(2-):DIN ratio has decreased in this area from the 1950-1960s to 2000s.The argument that phytoplankton productivity in the Changjiang estuary has been enhanced by increasing nutrient input from the riverine transport was supported by these results.A comparative study analyzing the shift of phytoplankton composition from the mid-1980s to 2000s was also made.The results indicated that the average yearly percentage of diatom species in the Changjiang estuary has decreased from 84.6% during 1985-1986 to 69.8% during 2004-2005.Furthermore,the average yearly percentage of diatom abundance in the Changjiang estuary decreased from 99.5% during to 75.5% over the same time period,while the abundance of dinoflagellates has increased dramatically,from 0.7% to 25.4%. 展开更多
关键词 EUTROPHICATION NUTRIENTS phytoplankton community Changjiang estuary
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Lake-margin ecosystems of saline lakes of the Borzya group(Zabaikalsky Krai, Russia) during the initial filling phase
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作者 Evgenia P.GORLACHEVA Gazhit Ts.TSYBEKMITOVA +4 位作者 Alexey V.AFONIN Natalya A.TASHLIKOVA Ekaterina Yu.AFONINA Alexey P.KUKLIN Natalia V.SALTANOVA 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期871-878,共8页
This article presents the results of hydrochemical and hydrobiological studies of shallow saline lakes of the Borzya group(Zabaikalsky Krai, Russia) at the initial filling phase. The lake-margin ecosystems of the stud... This article presents the results of hydrochemical and hydrobiological studies of shallow saline lakes of the Borzya group(Zabaikalsky Krai, Russia) at the initial filling phase. The lake-margin ecosystems of the studied lakes are characterized by varying degrees of salinity from polyhaline to brine water. Cyclical variations of meteorological conditions and high salinity determined that the compositions of the aquatic organisms are specific, mostly between stenohaline and euryhaline species, the quantities are low, and the community structures are simple. 展开更多
关键词 saline lakes HYDROCHEMISTRY WEEDS ZOOPLANKTON ZOOBENTHOS
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An Ecological Survey of Limoniastrum guyonianum: A Halophyte Native Tree in Arid Zones of Algeria
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作者 Chaff Mohammed El Habib Selkh Chouaib Bensoltane Ahmed 《Journal of Life Sciences》 2017年第7期333-340,共8页
In arid and semi-arid regions soil salinity is a constraint for the development of plants and a threat to balance food in these soils some species are threatened with extinction. Two natural constraints drought and sa... In arid and semi-arid regions soil salinity is a constraint for the development of plants and a threat to balance food in these soils some species are threatened with extinction. Two natural constraints drought and salinity have altered the ecosystem stability, but it has always conditions more or less favorable to the existence of a spontaneous flora adapted to the climatic and edaphic stress. The aim of this study is to describe a halophyte native tree and its climatic and edaphic requirements, it is a case of Limoniastrum guyonianum. According to this survey L. guyonianum, grows well under high temperature, insolation and evaporation and low rainfall and humidity. The species tolerate the soil basic pH, salinity, calcareous and do not need the organic matter and chlorure ions There are some morphological adaptations in the L. guyonianium to the several conditions as the length of the root and cylindrical shapes of the leaves and their extraction of salt. 展开更多
关键词 ARID SALINITY CLIMATIC EDAPHIC Limoniastrum guyonianum
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Coupling relation between water and salt in irrigation area on a catchments scale
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作者 WANG Rang-hui ZHAO Zhen-yong +1 位作者 ZHANG Hui-zhi NING Hu-sen 《Journal of Environmental Science and Engineering》 2009年第1期1-5,共5页
Water resource is the important factor for sustainable development in Weigan River catchments in western China. Based on ecological hydrology principles, the coupling relation between water and salt is monitored and a... Water resource is the important factor for sustainable development in Weigan River catchments in western China. Based on ecological hydrology principles, the coupling relation between water and salt is monitored and analyzed. The water quality for irrigation in oasis ecosystem has a larger variable range in arid area, which depending on the input water resource and underground water mineralization degree and water chemical component on the catchments scale, the water and salt coupling is decided by the climate condition and soil feature and vegetation characteristics as well as human activity. Meanwhile, temporal and spatial change between water and salt is quite complicated. The environmental management should be paid attention to considering in irrigation area in the catchments. 展开更多
关键词 water and salt relation catchment scale environmental management arid area
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