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1.
湖沼学是研究内陆水体的多学科整合科学——兼论我国湖沼学发展面临的挑战与机遇 总被引：1，自引：0，他引：1
湖沼学是研究内陆水体的多学科交叉综合性科学,自从Forel F.A.于1892年首次对湖沼学做出定义以来已有近130年历史.湖沼学的主要分支学科包括地质湖沼学(包括古湖沼学)、物理湖沼学、化学(生物地球化学)湖沼学和生物湖沼学.湖沼学的关键自然属性是通过跨学科的整合,从水生态系统水平综合分析相关过程与机理,并对生态系统变化进行预测.因此,湖泊学也是支撑水资源与生态系统保护、管理与修复的核心科学.然而,目前我国湖沼学发展面临分支学科发展不平衡、研究碎片化等问题,而人类活动加剧和气候变化对内陆水体生态系统的影响及管理对策是湖沼学研究面临的挑战与机遇.我国湖沼学研究亟需围绕人类活动、气候变化的影响,重点开展以下几个方面的工作:1)水动力与水文地貌特征变化及其环境生态效应; 2)营养盐和有机质生物地球化学循环及其环境生态效应; 3)食物网结构与功能; 4)外来入侵物种的影响与控制对策; 5)与水环境有关的传染病防治; 6)地表水生态评价; 7)生态系统演变机理与退化生态系统修复等. 相似文献
2.
广东流溪河水库湖沼学变量的时空动态特征 总被引：16，自引：7，他引：9
流溪河水库县位于北回归线上的大型山谷型水库,是一座典型的热带-亚热带过渡区水体.为了解该水库的特点,于2006年对水库的水文、营养盐状况及相关理化因子进行了逐月监测,对其主要的湖沼学变量的季节动态和空间分布进行了分析,探讨了湖沼学特征和生态过程的主要驱动因子.流溪河水库全年表层水温在14.9-31.6℃之间,水柱热分层开始于3月初,一直持续到12月,呈单循环混合模式.水库的水动力学主要受降水和水库用水的影响,2006年全年降雨量为2960mm,平均水力滞留时间长170d;降雨量集中在丰水期(4-9月),导致丰水期水力滞留时间短(65d),丰水期与枯水期水文水动力季节性差别显著,水文水动力学变化剧烈.2006年全年湖泊区的TN、TP、Chl.a、SD的平均值分别为0.66mg/L,0.016mg/L,2.2mg/m3,3.1m,指示该水库为贫中营养型水体.N/P的质量比为41:1,DIN/DIP的质量比为78:1,说明该水库浮游植物生长在强烈的磷限制性水体中,较高的N/P比是由流域中热带-亚热带红壤中营养盐组成特点所决定.营养盐、透明度和叶绿素a等变量的分布具有明显的时空异质性,丰水期初期(4-5月)营养盐浓度显著地高于其它月份,说明地表径流是输送营养盐入库的主要途径;沿入库河流至水库大坝方向,营养盐和Chl.a具有递减规律,即:河流区>过渡区>湖泊区.受季风的影响,丰水期的降水集中加上水库的本身形态是导致流溪河水库湖沼学特征呈显著的季节性和空间梯度的关键因素. 相似文献
3.
A major goal of paleolimnological studies is the quantification of past environmental conditions. This is accomplished by
computing transfer functions relating organism assemblages to environmental factors. The environmental data are typically
comprised of a point sample of water chemistry and other environmental parameters that are collected at the same time as a
surface sediment sample. We explore whether the year of sampling of the environmental variables affects the parameterization
of organism-environment relations, in particular chironomids, ostracodes and diatoms. Canonical correspondence analyses revealed
that the year of sampling is of secondary importance when relating the organism assemblages to environmental variables, but
only with the major explanatory variables. A chironomid-inferred bottom water temperature partial least squares transfer function
revealed similar performance statistics between the years. Taxon optima and tolerances were computed for both years using
weighted averaging, and the results are comparable. A paired t-test computed on the proxy-inferred bottom water temperature values indicated that the results between the 2 years are not
statistically different. The results of this study provide guarded optimism that the methodology of estimating transfer functions
as currently applied is not entirely determined by the particular year when the data were collected, although more case studies
are needed. 相似文献
4.
Several pressure sensors were deployed in a small lake to determine its storage change. It could be shown that a deep enough deployment and an averaging over a time interval of 1 hour and 5 measuring points allowed for a measurement of 1 or 2 kg/m2 (i.e. 2 mm of water column) of changes in the storage on the scale of the lake size. This accuracy for the lake storage could not be achieved by other methods, especially if conditions were difficult, e.g. snowfall, or in cases when precipitation was small. Finally, the pressure measurement - originally intended to roughly determine the water level - turned out to be a direct measurement of water mass in the lake, which was the proper magnitude for exchanges between atmosphere and lake. Hence the measurement of lake storage could become an interesting approach even for meteorological measurements, such as precipitation and evaporation on a water surface. 相似文献
5.
《Limnologica》2021
This contribution tells the history of the limnological institutes, which were founded at the shores of Lake Constance. The history starts in the late 19th century examining the scientific and personal background of two institutes, the “Anstalt für Bodenseeforschung” in Konstanz-Staad (no longer existing) and the “Institut für Seenforschung und Seenbewirtschaftung” in Langenargen, both founded in 1919/1920. It follows the turbulent history of the institutes during the early 20th century, the 3rd Reich, and the Federal Republic of Germany and examines their competition until their unification in 1970. A third institute, the precursor of the current Limnological Institute of the University of Konstanz was founded in 1948 in the small Black Forest village Falkau, and moved to Konstanz in 1970. In addition, the role of leading limnologists of their time, e.g. Max Auerbach, Reinhard Demoll, Hans-Joachim Elster and August Thienemann in founding and shaping these institutes is described. 相似文献
6.
《Limnologica》2020
As an essential component of lotic habitats, aquatic insects have commonly been used as bio-indicators of the ecological integrity of lotic habitats. However, recent large-scale declines have given rise to concerns about freshwater ecosystems functioning correctly. During three consecutive years, we surveyed Wadi Cherf, Upper Seybouse, Algeria, and employed the size-frequency distribution of head capsule width to sketch the life history of Oligoneuriopsis skhounate, an Ibero-Maghrebian endemic mayfly, whose distribution and ecology are not so well-known known. O. skhounate exhibited a seasonal univoltine summer cycle with growth and development taking place during the warmest period of the year (late spring to early autumn). The absence of nymphs during winter and the presence of last instar nymphs from July to November suggested a lengthy egg diapause, following the aestivo-autumnal emergence and reproduction. The study also raises the issue of freshwater biodiversity conservation in North Africa by highlighting the case of O. skhounate, acting as an indicator species of important but vulnerable aquatic ecosystems. 相似文献
7.
A survey of the modern physical setting of Lake El’gygytgyn, northeastern Siberia, is presented here to facilitate interpretation
of a 250,000-year climate record derived from sediment cores from the lake bottom. The lake lies inside a meteorite impact
crater that is approximately 18 km in diameter, with a total watershed area of 293 km2, 110 km2 of which is lake surface. The only surface water entering the lake comes from the approximately 50 streams draining from
within the crater rim; a numbering system for these inlet streams is adopted to facilitate scientific discussion. We created
a digital elevation model for the watershed and used it to create hypsometries, channel networks, and drainage area statistics
for each of the inlet streams. Many of the streams enter shallow lagoons dammed by gravel berms at the lakeshore; these lagoons
may play a significant role in the thermal and biological dynamics of the lake due to their higher water temperatures (>6°C).
The lake itself is approximately 12 km wide and 175 m deep, with a volume of 14.1 km3. Water temperature within a column of water near the center of this oligotrophic, monomictic lake never exceeded 4°C over
a 2.5 year record, though the shallow shelves (<10 m) surrounding the lake can reach 5°C in summer. Though thermally stratified
in winter, the water appears completely mixed shortly after lake ice breakup in July. Mean annual air temperature measured
about 200 m from the lake was −10.3°C in 2002, and an unshielded rain gage there recorded 70 mm of rain in summer of 2002.
End of winter snow water equivalent on the lake was approximately 110 mm in May 2002. Analysis of NCEP reanalysis air temperatures
(1948–2002) reveals that the 8 warmest years and 10 warmest winters have occurred since 1989, with the number of days below
−30°C dropping from a pre-1989 mean of 35 to near 0 in recent years. The crater region is windy as well as cold, with hourly
wind speeds exceeding 13.4 m s−1 (30 mph) typically at least once each month and 17.8 m s−1 (40 mph) in winter months, with only a few calm days per month; wind may also play an important role in controlling the modern
shape of the lake. Numerous lines of evidence suggest that the physical hydrology and limnology of the lake has changed substantially
over the past 3.6 million years, and some of the implications of these changes on paleoclimate reconstructions are discussed.
This is the second in a series of eleven papers published in this special issue dedicated to initial studies of El'gygytgyn Crater Lake and
its catchment in NE Russia. Julie Brigham-Grette, Martin Melles, Pavel Minyuk were guest editors of this special issue. 相似文献
8.
9.
Limnology of Two Antarctic Epishelf Lakes and their Potential to Record Periods of Ice Shelf Loss 总被引：1，自引：0，他引：1
James A. Smith Dominic A. Hodgson Michael J. Bentley Elie Verleyen Melanie J. Leng Steven J. Roberts 《Journal of Paleolimnology》2006,35(2):373-394
George VI Ice Shelf is the largest ice shelf on the western side of the Antarctic Peninsula and its northern margin marks
the southern most latitudinal limit of recent ice shelf retreat. As part of a project to reconstruct the long-term (Holocene)
history of George VI Ice Shelf we studied two epishelf lakes impounded by the ice shelf at Ablation Point, on the east coast
of Alexander Island. These lakes, Moutonnée and Ablation, are stratified water bodies with a lower marine layer and an upper
freshwater layer. To determine if their sediment records could be used to detect past changes in the presence or absence of
the ice shelf it was necessary to describe their present-day limnology and sedimentology. We measured water column chemistry
and sampled the water column and sediments of the lakes along vertical and horizontal transects. We analysed these samples
for diatoms, stable isotopes (δ18O, δ2H, δ13CDIC, δ13Corg), geochemistry (TOC, TN, C/N ratios) and physical sedimentology (grain-size). This was supplemented by chemical and biological
reference data from the catchments. Results showed that the water columns of both lakes are nutrient limited and deficient
in phytoplankton. Benthic productivity is low and decreases with depth. Comparison of water column chemistry with an earlier
survey shows a net increase in the thickness of the freshwater layer in Moutonnée Lake between 1973 and 2001, which could
indicate that George VI Ice Shelf has thinned during this period. However, a similar trend was not observed in Ablation Lake
(5 km to the north) and an alternative explanation is that the changes are a seasonal phenomena. Data from the surface sediment
transects identified a number of proxies that respond to the present day stratification of the water column including diatom
species composition, stable isotopes and geochemistry, particularly in Moutonnée Lake. Collectively these data have been used
to develop a conceptual model for determining past ice shelf configuration in epishelf lakes. Specifically, periods of past
ice shelf loss, and the removal of the ice dam, would see the present stratified epishelf lake replaced by a marine embayment.
It is suggested that this change would leave a clear signature in the lake sediment record, notably the deposition of an exclusively
marine biological assemblage, increased ice rafted debris and δ13Corg values that are indicative of marine derived organic matter.
These authors contributed equally to this work 相似文献
10.
中国科学院南京地理与湖泊研究所 《湖泊科学》2007,19(4):357-358
2007年4月25日起太湖梅梁湾暴发了大规模藻类水华暴发时间比过去提前近1个月.根据中国科学院太湖湖泊生态系统国家野外科学观测研究站的监测,5月2日梅梁湾所有测点藻类叶绿素a含量全部超过40μg/L,其中三山-鼋头渚水域达179μg/L;5月27日的卫星影像图片显示,太湖北部的竺山湾和贡湖湾以及整个西部湖区均发生了大面积的蓝藻水华;随后5月28日晚,无锡贡湖湾口南泉水厂发生污水团进入水厂取水口恶化水源水质事件,给人民的日常生活带来了短暂的影响. 相似文献