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1.
Through studying biological and ecological characteristics ofTamarix L., we found wide adaptability to different ecological environment and high endurance of adversity. When planted in the edge of desert and periphery of oasis,Tamarix will act as excellent sand-fixing shrubs, improve ecological environment and play a positive role. However, introducingTamarix unreasonably will deteriorate the ecological environment and reduce biodiversity and play a negative role. Grasping the biological and ecological characteristics ofTamarix will do much to benefit further developing and utilizing of the resources  相似文献   

2.
Through studying biological and ecological characteristics of Tarnarix L., we foundwide adaptability to different ecological environment and high endurance of adversity. Whenplanted in the edge of desert and periphery of oasis, Tamarix will act as excellent sand-fixingshrubs, improve ecological environment and play a positive role. However, introducing Tamarixunreasonably will deteriorate the ecological environment and reduce biodiversity and play a nega-tive role. Grasping the biological and ecological characteristics of Tamarix will do much to benefitfurther developing and utilizing of the resources.  相似文献   

3.
为探讨城市湖泊中抗生素的污染分布特征和生态风险,以宁波月湖为研究对象,利用固相萃取、超高效液相色谱串联质谱法(HPLC-MS/MS)对月湖水体抗生素进行分析,并采用生态风险熵值法(RQ)和混合抗生素的风险法(MRQ)评价磺胺类、大环内酯类、喹诺酮类、β-内酰胺类、林可霉素(LIN)等10种抗生素的生态风险情况.结果表明:氨苄西林(AMS)的检出浓度最高,浓度变化范围在ND~382.0 ng/L;其次为头孢氨苄(LEX)、诺氟沙星(NOR)、磺胺间甲氧嘧啶(SMM)、LIN、阿奇霉素(AZM)、磺胺噻唑(STZ)、磺胺甲恶唑(SMX)、泰乐菌素(TYL)和磺胺嘧啶(SDZ),浓度范围分别为ND~283.0、ND~267.0、ND~219.0、31.50~209.0、ND~147.0、7.34~109.0、ND~104.0、ND~80.50和20.40~57.30 ng/L.月湖水体中10种目标抗生素的水平总体上高于自然湖泊,尤其β-内酰胺类和LIN在城市湖泊中广泛存在.生态风险评估的结果表明,LIN、TYL、SMX、NOR、AMS的生态风险值(RQ)值均大于1,具有高的生态风险;其余5种抗生素处于中或低的生态风险水平.本研究为城市湖泊抗生素生态风险问题的深入研究提供了一定的科学依据和基础.  相似文献   

4.
2020年是长江禁渔开局之年,三峡库区作为长江的重要生态屏障,其水生态环境健康对长江大保护的实施具有重要意义。本文于2020年8月、11月及2021年1月、4月在三峡库区干支流共设置19个断面探究浮游植物群落结构特征,并利用生物量、多样性指数、综合营养状态指数和浮游植物Q指数等多种评价方法评价三峡库区水生态健康并分析其影响因素。结果表明:(1)三峡库区共鉴定出浮游植物8门105属266种,年平均丰度为6.4×104 cells/L,年平均生物量为0.038 mg/L。不同季节优势种组成不同,变异直链藻(Melosira varians Agardh)、骨条藻(Sheletonema spp.)、脆杆藻(Fragilaria spp.)为全年优势种。(2)三峡库区共划分24个功能群,B、D、MP、S1、P、Y为优势功能群。RDA分析表明,电导率、总氮、化学需氧量、总磷、pH、总溶解性固体与三峡库区四季功能群呈现显著关系。(3)相较于丰度、生物量和多样性水质评价结果,浮游植物Q指数更适用于三峡库区水生态评价,显示三峡库区干流水生态环境总体较好,但春、夏两季支流浮游植物...  相似文献   

5.

Water relation characteristics of the desert legumeAlhagi sparsifolia were investigated during the vegetation period from April to September 1999 in the foreland of Qira oasis at the southern fringe of the Taklamakan Desert, Xinjiang Uygur Autonomous Region of China. The seasonal variation of predawn water potentials and of diurnal water potential indicated thatAlhagi plants were well water supplied over the entire vegetation period. Decreasing values in the summer months were probably attributed to increasing temperatures and irradiation and therefore a higher evapotranspirative demand. Data from pressure-volume analysis confirmed thatAlhagi plants were not drought stressed and xylem sap flow measurements indicated thatAlhagi plants used large amounts of water during the summer months. Flood irrigation had no influence on water relations inAlhagi probably becauseAlhagi plants produced only few fine roots in the upper soil layers. The data indicate thatAlhagi sparsifolia is a drought-avoiding species that utilizes ground water by a deep roots system, which is the key characteristic to adjust the hyper-arid environment. Because growth and survival ofAlhagi depends on ground water supply, it is important that variations of ground water depth are kept to a minimum. The study will provide a theoretical basis for the restoration and management of natural vegetation around oasis in arid regions.

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6.
《国际泥沙研究》2016,(2):110-119
Rivers play an important role in people's living and agricultural production, however, intense human activities have broken the original ecological balance, and affected structures and functions of the river ecosystem. To restore the damaged river ecosystem back to a healthy status, effective ecological restoration measures need to be implemented. The main problems that the damaged rivers face are either the locally altered hydrological processes affected by construction of hydraulic facilities, or the deterioration of water quality resulted from pollution emissions, or both. In this study, ecological restoration techniques of the rivers affected by engineering control or pollution are reviewed respec-tively. In addition, three kinds of methods, i.e. physical, chemical and biological–ecological methods are introduced in details for the rivers affected by water pollution. At present, the development of river restoration techniques shows the following trends: 1) the scale of ecological restoration is becoming larger; 2) ecological restoration measures are required to meet multiple objectives; and 3) the man-agement of water environment is changing from water quality management to aquatic ecosystem management.  相似文献   

7.
The spreading of bacteria of the genusAeromonas in intensive fish rearing tanks was analyzed during one year. Lysotyping has established epidemiologic correlations between the strains ofAeromonas isolated from the aquatic environment and those of clinical (human) origin.

Dédié à Wolfgang Geiger  相似文献   

8.
Abstract

Maintaining and restoring the ecological integrity of floodplains remains a priority for many Australian federal and state government agencies. The Murray-Darling Basin Authority (MDBA) introduced the Proposed Basin Plan 2012, the Australian government’s latest basin-scale water planning instrument to promote a healthy, working river system. The proposal seeks to limit surface water (consumptive) use to 10 873 GL year-1 on a long-term average. The controversy prompted by this proposed reduction has underscored a need for rigorous and transparent modelling of ecological benefits. In this paper, we investigate the likely ecological outcomes of the proposal for Yanga National Park, one of the most significant environmental assets in the Murray-Darling Basin, using a decision support system. Our results indicate that the proposal will increase the inundation extent with a 33% (or 7000 ha) increase in median flood. The increase in inundation would improve the hydrological conditions in most wetlands in terms of the frequency and duration of events and inter-flood dry periods and enhance the habitat quality for a range of biota, though benefits are not distributed evenly across the wetland.
Editor D. Koutsoyiannis; Guest editor M. Acreman

Citation Wen, L. and Saintilan, N., 2014. Linking local ecological outcomes with basin-wide water planning: a case study of Yanga National Park, an important Australian inland forested wetland. Hydrological Sciences Journal, 59 (3–4), 904–915.  相似文献   

9.
现代分子生物学技术为蓝藻的生物多样性研究提供了更多信息和证据.单细胞蓝藻——双囊藻属(Geminocystis)是2009年从集胞藻(Synechocystis)分离出来的新属.2017年5月从青海湖的封闭子湖——月牙湖采集分离到一株单细胞蓝藻藻株,16S rRNA基因序列显示此藻株和双囊藻的藻种显示出最高的相似性,都在97%以上,并且在分子系统树聚为一束.此株的细胞结构以及超微结构显示,细胞纵轴具有窝式结构以及类囊体不规则的排列等双囊藻属所具有的特征.双囊藻是我国蓝藻的新报道纪录属,本研究还对双囊藻的分类和生态进行了讨论.  相似文献   

10.
The Niwot Ridge and Green Lakes Valley (NWT) long-term ecological research (LTER) site collects environmental observations spanning both alpine and subalpine regimes. The first observations began in 1952 and have since expanded to nearly 300 available datasets over an area of 99 km2 within the north-central Colorado Rocky Mountains that include hydrological (n = 101), biological (n = 79), biogeochemical (n = 62), and geographical (n = 56) observations. The NWT LTER database is well suited to support hydrologic investigations that require long-term and interdisciplinary data sets. Experimentation and data collection at the NWT LTER are designed to characterize ecological responses of high-mountain environments to changes in climate, nutrients, and water availability. In addition to the continuation of the many legacy NWT datasets, expansion of the breadth and utility of the NWT LTER database is driven by new initiatives including (a) a catchment-scale sensor network of soil moisture, temperature, humidity, and snow-depth observations to understand hydrologic connectivity and (b) snow-albedo alteration experiments using black sand to evaluate the effects of snow-disappearance on ecosystems. Together, these observational and experimental datasets provide a substantial foundation for hydrologic studies seeking to understand and predict changes to catchment and local-scale process interactions.  相似文献   

11.
Urban stormwater runoff discharged through sewer systems into streams causes flush spills of water and pollutants in the receiving water. To make the right decisions in future plannings of the very costly rehabilitation of sewer systems, a solid ecological data base on the critical parameters of sewer overflows is badly needed. Therefore, we designed a laboratory flume which was operated in circular flow mode (to ensure adaptation of the test organisms) and in flow-through mode during the simulation of sewer overflows (to allow a proper evaluation of population loss by drift). Examples on the behaviour during the adaptation phase and the population loss during the exposure to flush spills of water and/or a mixture of sewage and clean water of a benthic invertebrate (Gammarus pulex) demonstrate the potential of the flume to identify critical parameters of sewer overflows at quasireal-world-conditions. We found clear evidence for synergetic effects since the exposure to high flow and sewage caused higher population loss ofGammarus than the sum of population loss at exposure to only high flow or only sewage. Population loss considerably depended on the availability of refugial space: if the interstices of the gravel in the flume were silted, this loss was higher than at open interstices. Only ten minutes of movement of the material forming the flume bottom reduced the population ofGammarus to about 60 or 50% of its initial size. Hence, our data strongly suggest that the characteristics of the receiving stream (refugial space, bed stability) play an important role for the potential ecological impact of a sewer overflow. Changes of stream morphology and/or creation of refugial space plus an appropriate technical solution for overflow treatment may be less costly and more effective than a large-scale technical project. Thus, the stream itself should be a major element in future management decisions.  相似文献   

12.
Abstract

Ecological flow needs (EFN) frameworks incorporate a range of ecologically-relevant hydrological variables based on prior knowledge of river regime characteristics. However, when applied in cold regions, these approaches have largely ignored the influence of winter ice cover and the spring freshet on hydrological regimes: key components of river systems in cold regions with important direct effects on water quality, aquatic habitat and ecology. Here, we combine a review of the published literature on cold-regions hydrology and hydro-ecology with available hydrometric information for sites across Canada, a major cold-region country, to explore phenomena unique to these systems. We identify several ecologically-relevant hydrological measures (i.e. annual ice on/off dates, ice-cover duration, spring freshet initiation, peak water level during river ice break-up), pairing these with established metrics for incorporation into an enhanced suite of indicators specifically designed for cold regions. This paper presents the Cold-regions Hydrological Indicators of Change (CHIC), which can provide the basis for the assessment of EFN and climate change assessments in cold-region river ecosystems.
Editor Z.W. Kundzewicz; Guest editor M. Acreman

Citation Peters, D.L., Monk, W.A., and Baird, D.J., 2014. Cold-regions Hydrological Indicators of Change (CHIC) for ecological flow needs assessment. Hydrological Sciences Journal, 59 (3–4), 502–516.  相似文献   

13.
崔旭  张兵  何明霞  夏文雪  王义东  赵勇 《湖泊科学》2021,33(6):1675-1686
生态补水是维持和改善白洋淀生态环境的重要途径.为研究生态补水对白洋淀水环境的影响,分别在补水前与补水后采集淀水、河水及地下水样品,分析区域地表水和地下水水化学特征.结果表明:(1)白洋淀补水前、后地表水与地下水的水化学组成中Na+为主要阳离子,补水后阴离子以HCO3-为主,淀区南部地表水电导率高;补水后地表水与地下水Ca2+、Mg2+和HCO3-浓度显著增加,水体电导率降低.(2)补水前地下水为Na-HCO3型水,地表水主要为Na-Cl·SO4及Na-Cl·HCO3类型;补水后地表水与浅层地下水向Ca·Mg-HCO3型演化,深层地下水水化学类型基本保持不变.(3)生态补水使白洋淀水位升高,淀区水面积增大,缓解了水资源短缺的问题;同时也使浅层地下水水化学组成发生改变,而深层地下水暂未受到影响.生态补水后,受稀释和混合作用的影响,水体Na+、Cl-和SO42-浓度显著下降,Ca2+、Mg2+及HCO3-浓度增加.在白洋淀生态补水中应"先治污,后补水",以减少补水过程中污染物向淀区的运移,还应注意区域地下水位上升过程中的阳离子交换及水岩相互作用,为合理调配生态补水及改善白洋淀生态环境提供科学依据.  相似文献   

14.
Yin  Yu  Li  Wanchun  Yang  Xiangdong  Wang  Sumin  Li  Shijie  Xia  Wielan 《中国科学:地球科学(英文版)》2001,44(1):316-323

Living ostracod and hydrochemical samples were collected synchronously from more than 50 lakes and small water body in the eastern edge area of the Tibetan Plateau, Northern Tibetan, Southern Tibet and mid-Tibet. The comparison of the adult body length ofLimnocythere inopinata and hydrochemical parameters of their habitats shows that a quantitative relationship exists between the adult body length and salinity expressed as conductivity. An empirical formula to reconstruct paleosalinity is suggested first and applied to salinity reconstruction of CE-2 core from Cuoe Lake, Tibet. The method is verified by comparing its outcome with results of other environment reconstruction methods.

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15.
The EU Water Framework Directive demands the protection of the functioning and the structure of our aquatic ecosystems. The defined means to realize this goal are: (1) optimization of the habitat providing conditions and (2) optimizing the water quality. The effects of the measures on the structure and functioning of the aquatic ecosystems then has to be assessed and judged. The available tool to do this is 'monitoring'. The present monitoring activities in The Netherlands cover target monitoring and trend monitoring. This is insufficient to meet the requirements of the EU. It is, given the EU demands, the ongoing budget reductions in The Netherlands and an increasing flow of unused new ecological concepts and theories (e.g. new theoretical insights related to resource competition theory, intermediate disturbance hypothesis and tools to judge the system quality like ecological network analysis) suggested to reconsider the present monitoring tasks among governmental services (final responsibility for the program and logistic support) and the academia (data analyses, data interpretation and development of concepts suitable for ecosystem modelling and tools to judge the quality of our ecosystems). This will lead to intensified co-operation between both arena's and consequently increased exchange of knowledge and ideas. Suggestions are done to extend the Dutch monitoring by surveillance monitoring and to change the focus from 'station oriented' to 'area oriented' without changing the operational aspects and its costs. The extended data sets will allow proper calibration and validation of developed dynamic ecosystem models which is not possible now. The described 'cost-effective' change in the environmental monitoring will also let biological and ecological theories play the pivotal role they should play in future integrated environmental management.  相似文献   

16.
统计分析了青藏高原不同区域水体环境表层沉积物陆相介形类的属种分布特征,探讨了介形类在不同水环境下(盐度、pH值及水深)对生态环境的响应.结果显示,青藏高原现生介形类共计21属67种,其中Candona candidaIlyocypris bradyiEucypris inflataLimnocythere dubiosaLimnocythere inopinataParacypricerus angulataLeucocytherella sinensisLeucocythere mirabilis为青藏高原地区的常见种.湖泊、河流、洼地和湿地4类水体环境中,湖泊中介形类最为丰富,达19属62种;青藏高原东北部(祁连山和柴达木盆地)、北部(昆仑山)、西部和南部不同区域的介形类常见种存在较大差异,可能是区域海拔、pH值和盐度综合作用的结果.淡水和微咸水环境介形类属种数量较咸水及盐湖中丰富,分别有17属41种和13属42种,Limnocythere dubiosa (0.52~90.6 g/L)和Leucocythere mirabilis(0.51~174.63 g/L)在淡水、咸水及盐湖中均有出现,适应盐度范围较广;pH值在8.0~10.0范围内介形类属种多样性最丰富,表明大部分介形类具有嗜碱性的特征;青藏高原陆相介形类属种多样性随水深的增加而降低,浅湖(0~15 m)中介形类属种最为丰富,达到17属52种,其中Candona candida(0.2~80 m)和Leucocythere dorsotuberosa(0.3~110 m)从滨湖至深湖区均有分布,二者均具有较大的水深适应范围.  相似文献   

17.
基于洱海水生态特征的流域最大日负荷总量控制   总被引:1,自引:1,他引:0  
基于洱海水生态历史数据及现状资料,采用概率密度分布曲线法及水生生物基准相结合的方式计算洱海总氮(TN)、总磷(TP)、高锰酸盐指数(COD_(Mn))和氨氮(NH_3-N)的控制目标,目标值分别为0.36、0.026、4和0.28 mg/L.再根据该水质目标,得到洱海的最大日负荷(TMDL)总量.TMDL总量采用线性规划法计算,其中污染物响应系数矩阵通过MIKE 21二维水质模型计算所得.安全容余(MOS)则通过一阶误差分析法确定.经过一系列的计算,最终确定洱海的TMDL总量控制计划.计算结果表明,洱海TN、TP、COD_(Mn)和NH_3-N的TMDL总量分别为2005.989、149.671、19258.844和1348.119 kg/d,其MOS所占比例分别为6.152%、5.570%、4.380%和5.021%,表明洱海农业面源污染为该流域主要的污染形式,其允许最大排放量约占全部允许排放量的90%左右.  相似文献   

18.
Temporal sequential analyses of the hydrological observational data in the Tarim Basin over the last forty years revealed an annual increase of 2× 107m3 in the water quantities at the three headstreams of the upper courses and an annual decrease of 3 × 107m3 in the water flow from Alaer, which is on the upper main stream. A prediction of the trends indicates that there can be severe situations under which intermittent water interceptions occur. By means of approximate estimations on vegetative water consumption through phreatic evaporation combined with a quota assessment, the ecological water demands required to maintain the ecological environment in the mainstream area over the three different targeted years of 2005, 2010 and 2030 are defined as standing at 31.86 × 108m3, 36.27 × 108m3 and 41.04 × 108m3 respectively. Ecological fragility indexes are established on the basis of the selection of environmental sensitivity factors. Rational evaluations give proof that the lower reaches of the mainstream have already turned into zones where their ecological environments are gravely damaged. Multi-objective optimization should be conducted and protective schemes be framed within the threshold limits of the bearing capacities of water resources and the environment  相似文献   

19.
Summary The amount of 10 and 11 amino acids respectively has been estimated in (a) a complete specimen ofAbramis brama; (b) muscles ofSalmo irideus; (c) Tubifex sp.

6. Mitteilung (im Druck) siehe C. r. XXIIe Congr. Chimie industr. (Barcelona) 1949. 5. Mitteilung (im Druck) siehe Verh. Schweiz. naturf. Ges. (Lausanne), 1949.  相似文献   

20.
《Marine pollution bulletin》2008,56(10-12):407-414
The EU Water Framework Directive demands the protection of the functioning and the structure of our aquatic ecosystems. The defined means to realize this goal are: (1) optimization of the habitat providing conditions and (2) optimizing the water quality. The effects of the measures on the structure and functioning of the aquatic ecosystems then has to be assessed and judged. The available tool to do this is ‘monitoring’. The present monitoring activities in The Netherlands cover target monitoring and trend monitoring. This is insufficient to meet the requirements of the EU. It is, given the EU demands, the ongoing budget reductions in The Netherlands and an increasing flow of unused new ecological concepts and theories (e.g. new theoretical insights related to resource competition theory, intermediate disturbance hypothesis and tools to judge the system quality like ecological network analysis) suggested to reconsider the present monitoring tasks among governmental services (final responsibility for the program and logistic support) and the academia (data analyses, data interpretation and development of concepts suitable for ecosystem modelling and tools to judge the quality of our ecosystems). This will lead to intensified co-operation between both arena’s and consequently increased exchange of knowledge and ideas. Suggestions are done to extend the Dutch monitoring by surveillance monitoring and to change the focus from ‘station oriented’ to ‘area oriented’ without changing the operational aspects and its costs. The extended data sets will allow proper calibration and validation of developed dynamic ecosystem models which is not possible now. The described ‘cost-effective’ change in the environmental monitoring will also let biological and ecological theories play the pivotal role they should play in future integrated environmental management.  相似文献   

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