首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
东营凹陷古近系古湖盆演化与水化学场响应   总被引:12,自引:2,他引:10  
陈中红  查明  刘太勋 《湖泊科学》2008,20(6):705-714
采用人工配制污水为实验用水进行室内水培实验,研究10种人工湿地中常见水生植物对氨氮和总磷的同化吸收能力,筛选出净化效果好的植物,构建植物组合,以单一植物为对照,研究植物组合对于提高氨氮、总磷净化效果的作用.结果表明:不同植物对氨氮、总磷的去除能力差别较大千屈菜(Lythrum salicaria)、菖蒲(Acorus calamus)、美人蕉(Cannindica)、达香蒲(Typha davidiana)对氨氮净化效果较好,初始浓度2969mg/L、15d后,去除率966%、98.6%、877%、95.1%美人蕉、凤眼莲(Eichhornia crssipes)、干屈菜、石菖蒲(Acorus tartarinowii)对TP净化效果较好,初始浓度4.44mg/L、15d后,去除率99.0%、546%、69.9%、36.7%千屈菜与石菖蒲的组合能同时提高氨氮与总磷的净化效果;美人蕉与干屈菜的组合、菖蒲与美人蕉的组合、菖蒲与千屈菜的组合、美人蕉与石菖蒲的组合能提高总磷的净化效果组合实验结果表明,适当的水生植物组合能提高氨氮与总磷的净化效果。  相似文献   

2.
人工湿地植物研究   总被引:193,自引:10,他引:193  
本文阐述了植物在人工湿地污水净化过程中作用及存在的若干问题,提出了研究人工湿地植物的一些设想,植物在人工湿地中起着非常重要的作用,不但直接摄取利用污水中的营养物质、吸收富集污水中的重金属等有毒有害物质;而且输送氧气到根区,提供根区微生物生长、繁殖和降解对氧的需求;还能维持和加强人工湿地系统内的水力学传输,但目前人工湿地植物的应用还存在着枯死衰退、杂草丛生和根系扩展较浅等问题,影响人工湿地的净化功能,通过对人工湿地植物生理生态特性如气体代谢、光合作用、逆境生理和相生相克等研究,筛选出优良植物种类,创造适宜人工生,将有利于发育发挥湿地植物功能,提高人工湿地污水处理能力。  相似文献   

3.
We present the process of developing a macrophyte based index (River Macrophyte Index – RMI) for assessing river ecological status, that would be applicable for rivers with moderate to high water alkalinity, flowing over low slope terrain. A reference value and boundary values were determined for five ecological classes. The relation between the developed index and two existing indices, the Reference Index (RI) and the Trophic Index of Macrophytes (TIM), and selected environmental variables was established. The RMI is based on species composition and abundance from 208 sampling sites being in reference or good hydromorphological conditions and differing in the catchment land use. The percentage of natural areas in the sub-catchment was used for classifying macrophyte taxa into 5 ecological groups. 65 plant taxa, of which 47 were identified as indicator taxa, were included in the analysis. To assess the ecological status of a river site, the presence of at least 3 indicator taxa is necessary, otherwise the assessment is considered inconclusive. RMI is expected to indicate multiple pressures on the river, including trophic level. The developed index and RI and TIM indices differed in relation to slope, distance to source and catchment size.  相似文献   

4.
Macrophyte community diversity and composition respond to ecosystem conservation and local environmental factors. In this study, we developed a multidimensional diversity framework for macrophyte communities, including the taxonomic and functional alpha and beta diversity. We used the framework to explore the relationships among water level regimes and these diversity parameters in a case study of China's Baiyangdian Lake. Analysis of indicators of hydrologic alteration divided the water level from 1959 to 2019 into four regimes (dry, <6.42 m; low, 6.42–7.23 m; medium, 7.23–8.19 m; high, >8.19 m). Alpha and beta diversity were significantly higher in the medium regime than in the low and high regimes. Redundancy analysis indicated that the maximum water depth significantly affected taxonomic alpha diversity, and total nitrogen (TN) and chemical oxygen demand (COD) concentration significantly affected functional alpha diversity, respectively. Mantel tests showed that TN, Secchi depth (SD), and water depth in the high water level regime significantly increased the total beta diversity and turnover components. TN was the main factor that increased total taxonomic beta diversity. Water level regime mainly influenced interspecific relationships by changing the TN and COD concentration. The water level should be maintained between the medium and high water level regimes to promote restoration of the macrophyte community and improve ecosystem stability. The biodiversity evaluation framework would provide a deeper insight into the hydrological process management for restoration of aquatic macrophyte communities in shallow lakes.  相似文献   

5.
Aquatic macrophytes produce large amounts of organic matter and have an essential structuring role in floodplains. This process highlights the importance of this community to aquatic biodiversity maintenance. We investigated the role of a flood disturbance on the response of macrophyte assemblages in regional and local structuring in the Upper Paraná River floodplain. Plant species were recorded before (November 2006) and after (March 2007) an uncommon increase in water level caused by the El Niño South Oscillation, which is considered a disturbance. Samples were taken in lakes and backwaters located in the floodplain and connected to three distinct rivers (that differentiate three sub-systems). Species richness and the assemblage structure of macrophyte patches underwent significant changes after the flood disturbance, depending on the specific sub-system (rivers) to which the lakes were connected. In addition, flood disturbance had a strong impact on community organization at the local scale. However, regionalization with respect to sub-systems remained significant after the flood disturbance. Our results emphasize the importance of connection to the river on macrophyte community composition and richness, and suggest that flood events in the Upper Paraná River floodplain disrupt community organization only at fine (local) scales.  相似文献   

6.
Variation in habitat structure provided by macrophytes is regarded as one of the determinants of macroinvertebrate species composition in lentic ecosystems, but mechanisms underlying this relationship appear to be confounded with site-specific factors, such as physicochemical factors, epiphyton and composition of the vegetation. To better understand the relationship between structural complexity of a macrophyte stand and its macroinvertebrate assemblage composition, it is essential to determine the ecological role of different components of habitat structure for the phytomacrofauna. Using artificial structures as macrophyte mimics, representing three growth forms (stems, broad-leaved, finely dissected) and three structure surface areas (0.1, 0.2, 0.3 m2), a full factorial field experiment was conducted in a series of drainage ditches. We investigated if macroinvertebrate assemblages colonizing the structures were affected by an increase in macrophyte structure surface area, structural complexity, or by a combination of both, and if the observed patterns were consistent among sites differing in physicochemical and habitat characteristics. Assemblages were characterized both in terms of taxonomic and functional composition, because we expected that non-taxonomic aggregation of species into functional categories would give a different insight in habitat complexity-macroinvertebrate relationships in comparison to approaches based on the taxonomic assemblage composition. Ditch intrinsic factors, in part reflected in the periphyton on the structures, explained the major proportion of the variance in both the taxonomical macroinvertebrate assemblages and functional groups among structures. Contrary to our expectation, patterns in the taxon-based and functional dataset resembled each other. Only a minor contribution of growth form to the explained variance was observed in the taxonomical dataset, whilst differences in functional composition were unrelated to habitat structure. In conclusion, processes operating on larger spatial scales overrode the micro-scale effects of habitat structural complexity and surface area on macroinvertebrates.  相似文献   

7.
Artificial surfaces, characterized with intensive land-use changes and complex landscape structures, are important indicators of human impacts on terrestrial ecosystems. Without high-resolution land-cover data at continental scale, it is hard to evaluate the impacts of urbanization on regional climate, ecosystem processes and global environment. This study constructed a hierarchical classification system for artificial surfaces, promoted a remote sensing method to retrieve subpixel components of artificial surfaces from 30-m resolution satellite imageries(Globe Land30) and developed a series of data products of high-precision urban built-up areas including impervious surface and vegetation cover in Asia in 2010. Our assessment, based on multisource data and expert knowledge, showed that the overall accuracy of classification was 90.79%. The mean relative error for the impervious surface components of cities was 0.87. The local error of the extracted information was closely related to the heterogeneity of urban buildings and vegetation in different climate zones. According to our results, the urban built-up area was 18.18×104 km2, accounting for 0.59% of the total land surface areas in Asia; urban impervious surfaces were 11.65×104 km2, accounting for 64.09% of the total urban built-up area in Asia. Vegetation and bare soils accounted for 34.56% of the urban built-up areas. There were three gradients: a concentrated distribution, a scattered distribution and an indeterminate distribution from east to west in terms of spatial pattern of urban impervious surfaces. China, India and Japan ranked as the top three countries with the largest impervious surface areas, which respectively accounted for 32.77%, 16.10% and 11.93% of the urban impervious surface area of Asia. We found the proportions of impervious surface and vegetation cover within urban built-up areas were closely related to the economic development degree of the country and regional climate environment. Built-up areas in developed countries had relatively low impervious surface and high public green vegetation cover, with 50–60% urban impervious surfaces in Japan, South Korea and Singapore. In comparison, the proportion of urban impervious surfaces in developing countries is approaching or exceeding 80% in Asia. In general, the composition and spatial patterns of built-up areas reflected population aggregation and economic development level as well as their impacts on the health of the environment in the sub-watershed.  相似文献   

8.
9.
Susanne Schneider   《Limnologica》2007,37(4):281-289
Ecological optima and ranges of submerged macrophytes are, amongst other factors, assumed to be influenced by ecoregion and flow velocity. In order to test the influence of ecoregion within Europe, species indicator values of three European macrophyte river trophic indices were compared to each other. Species indicator values of the United Kingdom (UK), French and German bioindication methods are significantly correlated with each other. The most obvious difference between the three indicator systems is the number of included indicator taxa. Two species exhibit major differences in indicator values: Callitriche hamulata has a broader ecological amplitude in Germany and France than in the UK, where it is restricted to oligotrophic rivers, while Ranunculus fluitans has a broad ecological amplitude in the UK, whereas the species is restricted to eutrophic rivers in Germany and France.

In order to test if current velocity has an influence on macrophyte trophic indicator qualities, species indicator values of a river (Trophic Index of Macrophytes, TIM) and a lake macrophyte trophic index (Macrophyte Index, MI), both of them applicable in Bavaria, Germany, were compared to each other. Species indicator values are significantly correlated. The most important difference is that different species are included in lake and river indicator lists. Only approximately 60% of the total species are used in both TIM and MI. Three species exhibit a major difference in ecological optima between rivers and lakes: Ranunculus circinatus has a broader ecological amplitude in rivers whereas the species is restricted to eutrophic lakes, Myriophyllum spicatum and Nuphar lutea show the opposite reaction.  相似文献   


10.
近几十年来,在入湖营养盐增加,水质持续下降,藻类生物量逐年升高及水位大幅波动下,洱海沉水植物群落演替速度加剧.2016年7月调查显示:洱海沉水植被退化严重,物种数量显著低于近期(2011年)历史水平,分布面积较有记录的历史最高水平(1980s)下降超过70%,优势物种由1960s的海菜花(Ottelia acuminata)、蓖齿眼子菜(Stuckenia pectinata)和大茨藻(Najas marina)等转变为微齿眼子菜(Potamogeton maackianus)、金鱼藻(Ceratophyllum demersum)以及苦草(Vallisneria natans).沉水植物群落在浅水区(0~2.5 m)主要遭受了浮叶植物细果野菱(Trapa maximowiezii)过度生长带来的生境胁迫,在中等水深区(2.5~4 m)面临微齿眼子菜和金鱼藻的过度生长导致的群落结构的单一化影响,而在深水区(>4 m)面临着面积萎缩的风险,这些严重抑制了沉水植物清水稳态效应的发挥.通过对比洱海典型湖湾洱滨村水域沉水植物群落结构在恢复与优化前后的变化,发现洱滨村水域各水深区间沉水植物群落各项多样性指标与恢复物种的丰度均显著提升.因此,我们总结提出了针对洱海典型富营养湖湾沉水植被恢复和管理的建议和对策,以期为后续进一步开展洱海生态系统恢复相关工作提供依据.  相似文献   

11.
Controlling factors for the occurrence of littoral macrophyte species were investigated in Lipno Reservoir (area: 46.5 km2; zmean: 6.6 m; zmax: 22 m; water residence time: 0.6 yr), a dam impoundment with moderately fluctuating water level (amplitude up to 4 m) which is used for hydropower and downstream flow augmentation. The options of supporting littoral macrophyte growth for improving the reservoir's ecological potential were evaluated according to the European Water Framework Directive's definitions. Macrophytes were examined at 115 sites, each 50 m long, along the whole reservoir perimeter at regular 1 km intervals. Sites were surveyed for their phytocoenology, shore morphometry, pedological characteristics of substrate, transparency of water, and anthropogenic impacts. Most of the sites were characterised by a wide eulittoral zone with a tenuous cover of terrestrial hydrophilic, amphibious, and/or emergent macrophytes and a low proportion of silt, clay, and organic fractions in the substrate. Infralittoral submerged and floating-leaved macrophytes were restricted to a few sites within the mouths of the main and side tributaries where transparency was maintained by clear inflow water independent of reservoir pool fluctuations. Water transparency was low (1-2 m) compared to annual changes of water level (2 to >3 m). Multivariate statistical analysis (DCA, CCA) confirmed relationships between the occurrence of macrophyte species and morphological and substrate characteristics of the shore. Improvement of macrophyte cover and establishment of vital infralittoral zones requires improvements in water transparency and changes in reservoir operation, i.e., limiting the range of water level fluctuation to less than ca. 1 m.  相似文献   

12.
The effect of regional and local ground water circulation systems on the Heat Flow Density (HFD) field is demonstrated by two examples from Switzerland, one near St. Gall in an area at the northern border of the Alps, and the other northwest of Zurich along the eastern end of the Jura mountains. Detailed HFD maps of both areas slow pronounced high heat flow zones which are attributed to discharge of subsurface water which has migrated laterally over several 10 km. Seepage velocities on the order of several mm/yr have been calculated. Geothermal information is not available about the infiltration zones where low HFD values are expected. Geochemical and isotopic analysis of water samples from springs and drillholes indicates the recharge zones and demonstrates the effect of extensive regional systems. These results indicate that in regions with significant topographic relief HFD mapping can be seriously biased if drillholes are positioned in valleys which correspond to discharge areas with relatively high HFD, whereas the low heat flow zones remain undetected.  相似文献   

13.
The distribution and abundance of macrophytes, land-use beyond the riparian zone, characteristics of the riparian zone and selected channel properties have been studied in 9 streams flowing through an agricultural landscape in the north-eastern part of Slovenia. The streams studied supported a rich macrophyte community. Altogether, 53 plant taxa were observed on 93 km of the streams. Canonical correspondence analysis indicated that 10 out of the 11 parameters examined significantly influenced macrophyte distribution. Of these, substrate characteristics and riparian vegetation type were the most influential. Species composition analysis revealed that the majority of species indicated moderate nutrient load while, in the more strongly modified reaches, species indicating eutrophic conditions, i.e. Myriophyllum spicatum and different species of genus Potamogeton, were more abundant.  相似文献   

14.
高效净化氮磷污水的湿地水生植物筛选与组合   总被引:14,自引:2,他引:12  
抚仙湖流域未进行生态修复的磷矿废弃地面积142&#215;10^4m^2,对磷矿废弃地污染物流失量和区域内径流污染物含量进行调查观测,并提出磷矿废弃地水污染防治对策.富磷矿石剖面和堆土场在风化作用和降雨淋溶作用下,大量氟、磷等元素释放,造成磷矿区内地表径流和地下渗流污染结合实测的磷矿废弃地面积和土柱淋溶实验得到的污染物淋溶量,估算得到磷矿废弃地每年F和TP的淋溶流失量为60.65t/a和2734t/a,随地表径流迁移进入抚仙湖的F和TP分别为22.58t/a和7.27t/a由此可见,磷矿开采是抚仙湖的一个持久污染源,对湖泊营养化演变进程起了推动作用。  相似文献   

15.
We examined the distribution of submerged and emergent macrophyte species and the entire macrophyte community within and between five lake types (highland reservoirs, alkali lakes, large shallow lakes, small to medium sized shallow lakes, marshes) in the Pannon Ecoregion, Hungary. The lowest submerged, emergent and total species richness was found in alkali lakes. The highest submerged macrophyte richness was in small to medium sized lakes, while the highest emergent macrophyte species richness was in reservoirs, small to medium sized lakes, and marshes. The values of within-lake type beta diversity were generally lower than the values of alpha diversity, especially for submerged macrophytes, indicating between site homogeneity in species composition within the lake types. Emergent macrophyte communities contributed the most to within and between lake type diversity and total (gamma) diversity. Canonical correspondence analyses showed that the main environmental variables which influenced the distribution of submerged macrophytes were conductivity, Secchi transparency and water nitrogen contents. For emergent macrophytes conductivity, lake width, altitude and water depth proved to be the most influential variables. Our results contribute to the knowledge of large-scale distribution of macrophytes in the Pannon Ecoregion and to the identification of conservation value of lakes using macrophytes. The results support the importance of small lakes and artificial lakes in the conservation of macrophyte diversity compared to large and natural lakes in the Pannon Ecoregion.  相似文献   

16.
为重建湖泊水生植被,改善太湖局部水域水质,在太湖康山湾示范区两个大型围隔进行了两种类型水生植物重建.通过2010年8月-2011年8月的现场采样及分析测定发现,人工控制条件下,浮叶植物荇菜和菱以及沉水植物马来眼子菜的重建效果较好,在其生长季节具有较高的覆盖度;研究表明,控制风浪及提高透明度是恢复水生植被的前提;植被重建区沉水植物氮、磷含量与浮叶植物差别不大,但浮叶植物重建区水体氮、磷浓度的控制比沉水植物重建区好;从经济及水环境效益角度来看,太湖敞水区的沿岸带由于风浪的控制比较困难,恢复水生植被时,应选择浮叶植物荇菜、菱、沉水植物马来眼子菜等抗风浪能力强的物种.本研究为太湖敞水区沿岸带的生态恢复方案制定提供了理论依据.  相似文献   

17.
Floristic surveys, vegetation mapping, and detailed transect analyses rendered a macrophyte flora of 14 native and five alien taxa of flowering plants in the River Erft, a contributory of the River Rhine in Northrhine-Westphalia. Water temperatures of this river do not fall below 10 °C all the year round, for reasons of geothermically heated water discharged from nearby opencast mining areas. Macrophyte stand structures, composed of the neophytes Azolla filiculoides and Lemna minuta (floating) and Myriophyllum aquaticum, Egeria densa, and Vallisneria spiralis (rooted in the muddy or sandy ground of the river) are described and the ecological requirements of these taxa are characterized. The alien species can be seen as elements that increase the α-diversity of the aquatic vegetation of the River Erft. They do not replace any of the native species, even if shifts in the competition dynamics occur. The colonization by neophytes of the abnormally warmed River Erft can be appreciated as paradigmatic for trends in the macrophyte vegetation of medium-sized rivers in Central Europe when climate-related or discharge-based heating of the waterbody occurs and propagules of alien plants imported by waterfowl or – more important – plants from aquarium waste will find suitable places of existence and spread.  相似文献   

18.
Natural ponds are perceived as spatially and temporally highly variable ecosystems. This perception is in contrast to the often-applied sampling design with high spatial but low temporal replication. Based on a data set covering a period of six years and 20 permanently to periodically inundated ponds, we investigated whether this widely applied sampling design is sufficient to identify differences between single ponds or single years with regard to water quality and macrophyte community composition as measures of ecosystem integrity.In our study, the factor “pond”, which describes differences between individual ponds, explained 56 % and 63 %, respectively, of the variance in water quality and macrophyte composition. In contrast, the factor “year” that refers to changes between individual years, contributed less to understand the observed variability in water quality and macrophyte composition (10 % and 7 % respectively, of the variance explained). The low explanation of variance for “year” and the low year-to-year correlation for the single water quality parameter or macrophyte coverage values, respectively, indicated high but non-consistent temporal variability affecting individual pond patterns.In general, the results largely supported the ability of the widely applied sampling strategy with about one sampling date per year to capture differences in water quality and macrophyte community composition between ponds. Hence, future research can be rest upon sampling designs that give more weight to the number of ponds than the number of years in dependence on the research question and the available resources. Nonetheless, pond research would miss a substantial amount of information (7 to 10 % of the variance explained), when the sampling would generally be restricted to one year. Moreover, we expect that the importance of multiple-year sampling will likely increase in periods and regions of higher hydrological variability compared to the average hydrological conditions encountered in the studied period.  相似文献   

19.
Inlay Lake is the second largest natural lake in Myanmar. Located in Shan State, in the eastern part of the country, it is a known biodiversity hotspot. The lake is negatively affected by an increasing local human population and rapid growth in both agriculture and tourism. In recent decades, several studies have listed faunistic and floristic groups in Inlay Lake, but there is still a general lack of knowledge about the aquatic macrophyte and phytoplankton community composition and abundance, and their interactions. To fill this knowledge gap, field surveys of biological and physical and chemical parameters were carried out in the period 2014–2017. They show that Inlay Lake is a shallow, clear water and calcareous lake, with nutrient concentrations indicating mesotrophic-eutrophic conditions. However, close to the shore, nutrient concentrations are generally higher, reflecting pollution from inflowing rivers, shoreline villages and floating gardens. Both the richness and abundance of aquatic macrophytes in Inlay Lake were high, with several species forming extensive stands in most of the lake over the whole survey period. Total phytoplankton and cyanobacterial biomass were low, but cyanobacteria included toxin-producing strains of Microcystis, suggesting that cyanobacterial and total phytoplankton biomass need to be kept low to avoid potentially harmful cyanobacterial blooms. Submerged macrophyte abundance and phytoplankton biomass were inversely correlated in the heavily vegetated northern lake area. Our survey suggests a great importance of the submerged macrophytes to the general water quality and the clear water state in Inlay Lake. Maintaining high macrophyte abundances should therefore be a goal in management strategies, both for Inlay Lake and other lakes in Myanmar. It is highly desirable to include macrophytes and phytoplankton in the lake monitoring in Myanmar.  相似文献   

20.
人工湿地植物的选择   总被引:66,自引:1,他引:65  
本文阐述了植物在人工湿地中的作用和选择人工湿地植物的一些原则,并分析了人工湿地在我国的应用前景.植物在人工湿地中起着非常重要的作用,不但可以去除污染物质,维持湿地环境,而且具有生态美学和经济价值;选择了人工湿地植物应考虑植物的适应性、耐污能力、净化能力、根系、经济和观赏价值以及物种间的合理搭配.最后指出,人工湿地技术在我国有广阔的应用前景.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号