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1.
<正>济南七十二名泉冠甲天下,其中尤以趵突、黑虎最为著名,在两大名泉的附近尚有漱玉泉、九女泉、金虎泉、任泉和五莲泉等泉水50余处。老济南府城的南护城河把这些泉串联了起来,形成了一个活的水系,为济南平添了一道亮丽的风景。特别是严冬时节,喷涌的泉水更为这个北方城市带来了无限活力。我很有幸,家就在这条水系旁边,步行到黑虎泉10分钟,到趵突泉15分钟。我常对人开玩笑  相似文献   

2.
藻类植物的cpDNA结构复杂,普遍缺失反向重复序列IR,且存在IR的藻类植物种类的cpDNA也有IR变短退化迹象.藻类植物的cpDNA包含的基因一般比高等植物要多,编码能力更强.藻类植物cpDNA全序列的测定方法主要是Fosmid文库构建,配合使用Long-PCR技术.该文对国内外有关藻类植物叶绿体基因组结构、叶绿体编码基因、叶绿体基因组在藻类系统发育中的应用以及藻类植物叶绿体基因组的提取和序列测定方法等进行综述,为藻类植物的系统发育和叶绿体起源以及功能基因组学的研究提供理论依据.  相似文献   

3.
藻类植物是最简单的光合营养(自养)有机体,经过长期的发展演化,形成了现代丰富多彩的藻类世界.藻类植物分布广泛,适应性很强,但多数藻类植物个体较小,因此往往不大引人注目,特别是淡水藻类,容易被人们忽视.不过,淡水藻类在自然界和人类生活中的作用是非常重要的.  相似文献   

4.
于2004年3月至2005年3月,首次对北京怀沙河、怀九河自然保护区的藻类植物进行实地调查研究,通过对区内10个采样点360余份水生藻类植物标本鉴定、统计,分析了该区藻类植物的区系组成、藻类时空分布特点.研究表明,该区共分布有藻类植物9门105属226种,其中以硅藻、蓝藻、绿藻3门为主,并有少量裸藻、甲藻、黄藻、红藻、金藻等分布;藻类植物由于受水体化学物质组成和物理性质的影响,各采样点及不同月份的种类组成和数量均有差异.怀九河源头的物种丰度和硅藻多度均最大,洞台、黄坎丝状蓝藻占优势,怀柔水库绿藻占优势;在时间分布上,7月物种丰度和藻类多度最大.通过对区内藻类分布规律及大量污染指示藻类的分析表明,该保护区的水体已经受到了一定程度的污染.  相似文献   

5.
正大名鼎鼎的娘子关,位于晋冀交接的山西省平定县境内。此关坐落于太行山腹,扼守三晋门户,地势极为险要,被誉为"天下第九关",相传是为纪念唐代平阳公主率兵驻守此地而得名。娘子关上风云激荡,历代为兵家必争之地,历史文化气息厚重,而关下的娘子关村碧水飞瀑,泉水潺潺,家家有流水,处处涌山泉,却是一派江南水乡似的安静平和,正可谓"楼头古戍楼边寨,城外青山城下河"。此地正是一处藻类植物采集的好去  相似文献   

6.
我国江河、湖海众多,海岸线长,藻类植物种类繁多,产量丰富。淡水中也有一定数量的藻类植物生存。藻类植物与人类之间有许多直接和间接的关系。 (一)藻类植物与渔业的关系在各种水域中生长的藻类,都直接或间接是鱼类的饵料,其中尤以小型藻类为佳。所有的鱼苗都以藻类与浮游动物为食,当浮游动物缺乏时,它们就只吃藻类。某些杂食性鱼类也偏食藻类,如(?)鱼(PHoxinus)。非洲鲫鱼、遮目鱼也主要以藻类为食料。当人们对池塘中施加肥料时,藻类能够大量繁殖,如绿球藻目(纤维藻、栅藻、小球藻等  相似文献   

7.
为了探究新疆北部主要地区(乌鲁木齐、阿勒泰、伊犁)湿地鼓藻类植物多样性分布规律及其特征,该研究通过文献查阅和标本采集鉴定等方式收集数据,采用G F指数方法进行物种多样性分析,利用Person相关分析和冗余分析(RDA)分析其与环境因子的关系,为新疆湿地鼓藻类植物资源的调查和淡水藻类多样性研究提供基本资料。结果表明:(1)研究区域共有鼓藻类植物189种,隶属于1门1纲2目6科18属;其中鼓藻科(Desmidiaceae)为优势科,有154种,占总种数的81.48%;优势属为鼓藻属(Cosmarium Corda ex Ralfs)、角星鼓藻属(Staurastrum Ralfs)和新月藻属(Closterium Nitzsch),共有137种,占总种数的72.49%。(2)阿勒泰地区鼓藻类植物的DFDGDF G值均最高,分别为2.6213、2.0828、0.5095。(3)研究区域鼓藻类植物的种类数量分布为:阿勒泰地区>乌鲁木齐及周边地区>伊犁地区,纬向因素的变化趋势较经向更明显。(4)Person相关分析显示,影响阿勒泰地区鼓藻类植物物种多样性的主要因子是大气温度,影响乌鲁木齐及周边地区是大气温度、电导率和经度,伊犁地区则与环境指标未显出相关性。(5)RDA分析表明, pH和大气温度是影响鼓藻类植物物种多样性和组成的主要因素。研究认为,新疆北部主要地区湿地鼓藻类植物存在较明显的地理分布差异,物种数呈现北多南少,东多西少的分布规律,其物种多样性和组成分布与环境因子存在一定的相关性,但不同地区、不同属类的鼓藻类植物与环境因子的相关性存在差异。  相似文献   

8.
根状物     
藻类植物没有根、茎、叶的分化 ,营固着生活的藻类植物是具有类似根、茎、叶的枝状体 ,植物体下部是分枝的根状物 ,根状物可以使藻体牢固地固着在海底的岩石上 ,如海带、石花菜的根状物。根状物实属假根 ,人们习惯称这些藻类植物的假根为根状物。根状物@张卫忠$滨州市第六中学!山东滨州256651  相似文献   

9.
汾河源头周丛藻类植物群落结构特征   总被引:3,自引:0,他引:3  
冯佳  谢树莲 《生态科学》2007,26(5):408-414
基于对汾河源头流域周丛藻类植物群落进行的生态调查,共鉴定出周丛藻类植物24属47种,分别隶属于蓝藻(Cyanophyta)、红藻(Rhodophyta)、黄藻(Xanthophyta)、硅藻(Bacillariophyta)和绿藻(Chlorophyta)5个门。汾河源头流域的周丛藻类群落主要有5类,即颤藻群落(Oscillatoria community)、刚毛藻群落(Cladophora community)、无隔藻群落(Vaucheria community)、水绵-双星藻群落(Spirogyra-Zygnema community)和串珠藻群落(Batrachospermum community)。文章还对该地区的周丛藻类群落的种类组成、结构特征等进行了研究,分析了该流域中不同海拔梯度的变化对周丛藻类群落种类数的影响。结果表明海拔对周丛藻类植物的生长影响不明显,周丛藻类植物种数与水流速度之间存在负相关性。通过对周丛藻类植物种类组成、群落结构特征的研究,为汾河源头流域的环境保护和生物资源保护提供基础资料。  相似文献   

10.
藻类植物浅说刘家熙藻类植物为自养的原植体植物。其特征是一般具光合作用色素,能行光合作用,制造养分供本身需要。生殖器官为单细胞构造,植物体无根、茎、叶的分化。藻类植物生态习性多种多样,但绝大多数是水生的,也有少数是气生的。生于水中的藻类,又因水中含盐分...  相似文献   

11.
The Great Artesian Basin is an aquifer system that underlies a large area of north-eastern Australia. The spring wetlands in the Great Artesian Basin are of conservation significance because they provide habitat for endemic species including fish, invertebrates and plants. Since European settlement massive quantities of water have been artificially extracted through bores, reducing spring-flows. Records of the springs of the Queensland section of the Great Artesian Basin (excluding Cape York Peninsula) were compiled from a range of historical sources. Most remaining active springs were visited and surveyed, the physical attributes of the springs described and their current status determined. Recharge springs occur in areas where the evidence suggests the basin is recharged by rainfall and 93% of the original 245 spring-groups in these areas are still active. Discharge springs occur in sections of the Basin down-gradient of the recharge areas and only 36% of the original 300 spring-groups in these areas have at least some springs that are still active. The capping of bores could provide a partial restoration of artesian pressure and enhance spring flows. Of the active spring-groups surveyed 26% have suffered major or total damage as a result of excavation of the wetlands. An emerging threat is the use of exotic grasses as ponded pastures, which have the ability to dominate the habitat of spring wetlands. The potential impacts of other threats including those associated with stock, exotic animals and fire are also discussed. Mitigating these threats requires a conservation strategy that seeks to protect remaining springs with high conservation values.  相似文献   

12.
The water quality needs of groundwater ecosystems are rarely considered. It is currently assumed that water quality guidelines for surface waters will also protect groundwater ecosystems and their fauna, but this assumption has not been tested. The aim of this study is to determine whether water quality guidelines specifically for groundwater ecosystems are needed and to provide a preliminary risk assessment for groundwater ecosystems in Australia. In the absence of sufficient toxicity data for true groundwater fauna, 48–96 h LC50 data for groundwater-dwelling invertebrate orders (e.g., Crustacea, Rotifera) are used as a surrogate and were compared, using Species Sensitivity Distribution (SSD) curves, to a full suite of surface taxa (including fish, insects, and algae). SSD curves were derived for a range of pesticides previously detected in Australian groundwaters and were fitted using the Burr Type III distribution. Significant differences in the sensitivities of surface and groundwater taxa to Atrazine and Chlorpyrifos were detected, indicating surface water quality guidelines are not always suitable to protect or best manage groundwater ecosystems. Water quality guideline values derived from the SSDs highlighted a significant threat of contamination to groundwater ecosystems from agricultural chemicals. Clearly water quality guidelines specifically for groundwater ecosystems are needed.  相似文献   

13.
1. A survey of thirty-two rheocrene springs in central Pennsylvania revealed that, Like Gammarus in lakes and streams, Gammarus minus is absent from springs with pH <6.0 and conductivity <25μS cm?1 (total range in pH = 4.6–7.7, and in conductivity = 14–411 μS cm?1). 2. In ten springs G. minus density was positively correlated with Ca2+ and Mg2+ hardness, but not with pH, unless three springs with either an exceptionally high velocity or extremely high densities of the potentially competing snail Fontigens nickliniana were omitted. 3. Adults were larger in the springs with few or no large predators than in those with more predators. In all ten springs, adult dry mass was unrelated to spring pH and ionic content, but brooding female dry mass covaried positively with Ca2+ and Mg2+ hardness in the five predator-poor springs. 4. Body water, Na and Ca contents and body mass/length ratios varied independently of spring pH and ionic content. Water content was inversely correlated with fat content, but even when expressed as a percentage of fat-free wet mass, it was unrelated to water chemistry. 5. In juveniles, males and non-brooding females, fat content varied independently of spring pH and ionic content, but in brooding females it was correlated with alkalinity and Ca2+ and Mg2+ hardness. The cost of reproduction in brooding females may have been a factor here; they had significantly lower per cent fat than did non-brooding females. Juvenile fat content did not differ significantly among spring populations, whereas adult fat content did. The per cent fat of brooding females covaried positively with body size among springs, and this was marginally true for non-brooding females, as well. The residuals of brooding female per cent fat against dry mass were not related to water chemistry. 6. Brood size (number of embryos in a brood) and brood mass varied significantly among populations, but independently of spring pH and ionic content. Both covaried positively with maternal body size among springs. The residuals of these relationships were unrelated to water chemistry, as was the percentage of females brooding. 7. G. minus from a pH 6 spring survived better and lost less body mass in acidic soft water than did those from a pH 7.6 spring. However, although G. minus has apparently been able to adapt (or acclimate) to pH 6 water it has failed to adapt to more acidic waters. A physiological or structural constraint may be involved because this species has probably had ample opportunity to evolve resistance to dilute acidic water. This hypothesis is consistent with the threshold effect observed: above pH 6 G. minus shows very little evidence of osmotic or metabolic stress, but beiow pH 6 viable populations apparently cannot survive at all. However, the gradual linear decrease in population density of G. minus with decreasing alkalinity and Ca2+ and Mg2+ hardness suggests that other factors may also be involved (e.g. a decrease in food quality).  相似文献   

14.
Misasa, which is well known for its radon hot springs, is a historical town located in Tottori Prefecture, Japan. The presence of the hot springs is noted in an 1164 entry in town records. The presence of radioactivity in the hot springs was recognized in 1914. Since ancient times, the spring water has been believed to be healthful. The town of Misasa has 90 radon hot spring sources, yielding a total volume of 3,000 tons of spring water a day. The concentration of 222Rn in the spring water ranges from 17.4 to 9,361 Bq per liter. A series of cancer mortality studies on the radon hot springs were conducted through the collaboration of scientists scattered throughout different Japanese cities. At present, no definite evidence has been discovered that indicates an increase of cancer mortality in the Misasa radon hot spring area. Even a lower risk was found for stomach cancers in both radon and no-radon hot springs.  相似文献   

15.
1. We examined species–environment relationships and community concordance between aquatic bryophytes and insects in boreal springs. We sampled bryophytes (Marchantiophyta and Bryophyta), benthic macroinvertebrates and environmental variables in 138 springs in Finland, spanning a latitudinal gradient of 1000 km. Macroinvertebrates were subdivided into two groups: Ephemeroptera, Plecoptera, Trichoptera and Coleoptera (EPTC taxa) and chironomid midges (Diptera; Chironomidae). Our aim was to test whether EPTC taxa could be used as surrogates in biodiversity surveys and bioassessment for the two less-well known organism groups, chironomids and bryophytes.
2. Bryophyte assemblages were clearly differentiated along gradients in thermal conditions and water chemistry (pH, conductivity). Chironomids and EPTC were also differentiated in relation to thermal conditions and, to a lesser extent, physical habitat variables, but were only weakly associated to spring water chemistry. Chironomid and EPTC assemblages were more concordant with each other than with bryophytes, but all concordances were relatively weak.
3. Our results suggest that even if the overall compositional patterns of the three taxonomic groups were significantly concordant, the relative importance of environmental drivers underlying their community compositions differed strongly. The results thus imply that spring bryophytes and insects are relatively poor surrogates for each other. The proportion of spring specialists was highest in bryophytes, promoting their primacy for spring bioassessment and biodiversity conservation. We suggest that adequate variation in water chemistry be assured to protect spring bryophyte biodiversity, whereas preserving the physical variation of springs is more important for macroinvertebrates.  相似文献   

16.
矿泉水是地下水从含水层中经长期与岩石相互作用形成、富含有益于人体的丰富矿物质和微量元素的一类顶级饮用地下水资源.在水资源污染严重而且生态环境不断恶化的今天,基于新的科技认知手段重新认识矿泉水的生态和健康效应,具有重要意义.黑龙江省五大连池风景区拥有着五大连池旅游疗养业赖以生存和发展的优质矿泉水资源,并且被应用于医疗和保健方面已有百余年历史,但是面临着资源量减少、环境污染等问题的威胁.本文主要针对五大连池矿泉水的形成过程、分布规律、水化学和微生物特征及其健康效应等进行综合评述,侧重其微生物特征的研究进展,提出了未来五大连池矿泉的研究展望.为了更好地保护和利用五大连池矿泉水,建议五大连池周边农场发展绿色生态农业,减少化肥的施用;在开发旅游和疗养资源的同时,要严格建立污染风险的评估和管控体系,减少“新型”环境污染物对地质生态环境的可能污染.  相似文献   

17.
Interest in climate change effects on groundwater has increased dramatically during the last decade. The mechanisms of climate‐related groundwater depletion have been thoroughly reviewed, but the influence of global warming on groundwater‐dependent ecosystems (GDEs) remains poorly known. Here we report long‐term water temperature trends in 66 northern European cold‐water springs. A vast majority of the springs (82%) exhibited a significant increase in water temperature during 1968–2012. Mean spring water temperatures were closely related to regional air temperature and global radiative forcing of the corresponding year. Based on three alternative climate scenarios representing low (RCP2.6), intermediate (RCP6) and high‐emission scenarios (RCP8.5), we estimate that increase in mean spring water temperature in the region is likely to range from 0.67 °C (RCP2.6) to 5.94 °C (RCP8.5) by 2086. According to the worst‐case scenario, water temperature of these originally cold‐water ecosystems (regional mean in the late 1970s: 4.7 °C) may exceed 12 °C by the end of this century. We used bryophyte and macroinvertebrate species data from Finnish springs and spring‐fed streams to assess ecological impacts of the predicted warming. An increase in spring water temperature by several degrees will likely have substantial biodiversity impacts, causing regional extinction of native, cold‐stenothermal spring specialists, whereas species diversity of headwater generalists is likely to increase. Even a slight (by 1 °C) increase in water temperature may eliminate endemic spring species, thus altering bryophyte and macroinvertebrate assemblages of spring‐fed streams. Climate change‐induced warming of northern regions may thus alter species composition of the spring biota and cause regional homogenization of biodiversity in headwater ecosystems.  相似文献   

18.
Springs are spatially restricted and insular ecotones. In the Alps, topography enhances this isolation. Springs are to a certain extent inhabited by organisms which are adapted to the relatively constant environmental conditions in springs. We examined thirty-six springs in eight different areas in the Swiss National Park (SNP) to understand if the macroinvertebrate assemblages of high-elevation springs are isolated or interconnected communities. We quantitatively and qualitatively sampled the macroinvertebrate assemblages of the springs and monitored environmental parameters. The similarity of the macroinvertebrate assemblages of the springs within and the dissimilarities between the different areas were relatively high; a clear spatial isolation was not evident. The differences of macroinvertebrate assemblages in different areas were explained by substrate parameters: springs in areas at lower altitudes were characterized by organic substrates and many water mite species. High-elevation springs were characterized by coarse inorganic substrates and Trichoptera of the genus Drusus. For spring conservation, it is important to decide on an individual basis if the loss of a single spring will have severe consequences for spring biodiversity.  相似文献   

19.
Degradation of groundwater-dependent ecosystems has raised a need for their restoration, but ecological responses to restoration are largely unknown. We evaluated the effectiveness of spring restoration using data from near-natural, restored, and human-impacted springs, the major impact being degradation of spring hydrology by forest drainage. We used both taxonomic (bryophytes, macroinvertebrates, and leaf-decomposing fungi) and functional (leaf breakdown) measures of restoration success. We expected that by reducing surface water input, restoration will improve spring hydrology and place spring ecosystems in a trajectory towards more natural conditions. Restored springs were thermally more stable than impacted springs and the contribution of surface water was greatly reduced. Bryophytes were more abundant in restored than in impacted springs but did not differ among restored and natural springs. Similarly, macroinvertebrate communities differed between restored and impacted springs whereas no difference was detected between restored and natural sites. Species diversity and functional attributes showed weaker responses to restoration. Our results suggest that restoration enhances spring habitat quality, and the first signs of biodiversity enhancement were also detectable only a few years post-restoration. Restoration clearly bears great promise as a conservation tool for the protection of this valuable component of regional freshwater biodiversity.  相似文献   

20.
Benthic macroinvertebrate communities were studied and environmental variables were measured in six rheocrene springs in Cantabria, northern Spain. Principal component analysis revealed two different spring types according to their physical and chemical characteristics. Springs from group A (GA) had higher temperature and conductivity, while springs in group B (GB) had higher values of pH, altitude, mean water velocity, percentage of boulders and coarse particulate organic matter. Total number of invertebrate taxa and individuals were not different between GA and GB springs. However, Shannon diversity index was significantly higher for GB springs. Analysis of similarities (ANOSIM) and non-metric multidimensional scaling (NMDS) analysis indicated that invertebrate assemblages from GA and GB springs were different. The snails Theodoxus fluviatilis and Bythinella sp., and the amphipod Echinogammarus spp. had higher densities in GA springs, whereas ephemeropterans, plecopterans, trichopterans and chironomids were more important in GB springs. Higher water velocities in GB springs interacting with predation by Echinogammarus tarraconensis may be responsible for the observed patterns on invertebrate community structure and composition. The taxonomic resolution limited our ability to detect crenobiontic taxa. Sampling aquatic, semi-aquatic and semi-terrestrial habitats are needed to account for the biodiversity patterns of spring habitats.  相似文献   

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