Investigation of inner-basin variation: Impact of large reservoirs on water regimes of downstream water bodies     

Xue Dai  Zhongbo Yu  Guishan Yang  Chong-Yu Xu  Rongrong Wan 《水文研究》2021,35(5):e14241

Large dams and reservoirs alter not only the natural flow regimes of streams and rivers but also their flooding cycles and flood magnitudes. Although the effect of dams and reservoirs has been reported for some vulnerable locations, the understanding of the inner-basin variation with respect to the effects remains limited. In this study, we analyse the Three Gorges Dam (TGD) built on the Changjiang mainstream (Yangtze River) to investigate the dam effect variations in the system of interconnected water bodies located downstream. We investigated the effect of flow alterations along the downstream river network using discharge time series at different gauging stations. The river–lake interactions (referring to the interactions between the Changjiang mainstream and its tributary lakes i.e. the Dongting and Poyang lakes) and their roles in modifying the TGD effect intensity were also investigated in the large-scale river–lake system. The results show that the water storage of the tributary lakes decreased after the activation of the TGD. Severe droughts occurred in the lakes, weakening their ability to recharge the Changjiang mainstream. As a consequence, the effect of the TGD on the Changjiang flow increase during the dry season diminished quickly downstream of the dam, whereas its impact on the flow decrease during the wet season gradually exacerbated along the mainstream, especially at sites located downstream of the lake outlets. Therefore, when assessing dam-induced hydrological changes, special attention should be paid to the changes in the storage of tributary lakes and the associated effects in the mainstream. This is of high importance for managing the water resource trade-offs between different water bodies in dam-affected riverine systems.  相似文献   

新疆S214公路台特玛湖干涸湖盆段风沙危害及防治     

蔡东旭  李生宇  王海峰  俞祥祥  王世杰  徐新文 《中国沙漠》2020,40(1):1-11

新疆S214（考干-米兰，考米线）公路位于库鲁克塔格沙漠东南缘，穿越台特玛湖干涸湖盆。由于该区气候干旱，风力强劲，沙源丰富，流动沙丘广布且快速移动，风沙危害对公路运输构成严重威胁。通过对风沙环境和风沙危害定位观测和土壤水盐特征系统调查，确定了风沙危害极为严重的公路区段，提出了合理的风沙防护措施及防沙体系结构。结果表明：该区具有明显的单风向风况，主要盛行ENE和NE风，偶有反向风沙活动，起沙风频率、输沙势、输沙率极高，属于高能-大比率风能环境；受土壤水分、盐分含量影响，地表紧实度差异较大，部分地段为极疏松的沙层，部分地段为紧实的盐壳；S214公路风沙危害防护区段为K4+900~K18+200，设计建造的阻-固-输相结合的机械-植物复合防沙体系，防沙效果明显，保障了道路安全运营。这一强风沙、高盐区公路防沙体系建设模式可为类似环境地区工程防沙提供借鉴。  相似文献   

Simulations of the Impact of Lakes on Local and Regional Climate Over the Tibetan Plateau     

Lingjing Zhu  Xin Liu  Lei Tian  Qunhui Zhang 《大气与海洋》2018,56(4):230-239

ABSTRACT

Because of the high elevation and complex topography of the Tibetan Plateau (TP), the role of lakes in the climate system over the Tibetan Plateau is not well understood. For this study, we investigated the impact of lake processes on local and regional climate using the Weather Research and Forecasting (WRF) model, which includes a one-dimensional physically based lake model. The first simulation with the WRF model was performed for the TP over the 2000–2010 period, and the second was carried out during the same period but with the lakes filled with nearby land-use types. Results with the lake simulation show that the model captures the spatial and temporal patterns of annual mean precipitation and temperature well over the TP. Through comparison of the two simulations, we found that the TP lakes mainly cool the near-surface air, inducing a decreasing sensible heat flux for the entire year. Meanwhile, stronger evaporation produced by the lakes is found in the fall. During the summer, the cooling effect of the lakes decreases precipitation in the surrounding area and generates anomalous circulation patterns. In conclusion, the TP lakes cool the near-surface atmosphere most of the time, weaken the sensible heat flux, and strengthen the latent heat flux, resulting in changes in mesoscale precipitation and regional-scale circulation.  相似文献   

Lakes of the Jom-Bolok Volcanoes Valley in the East Sayan Mts., Baikal region     

Shchetnikov  Alexander  Bezrukova  Elena V. 《地理学报(英文版)》2019,29(11):1823-1840

Journal of Geographical Sciences - This article describes the lake basins of the Jom-Bolok volcanic region in the East Sayan (the largest manifestation of the Holocene eruptions in Central Asia)....  相似文献   

Biogeochemistry of dissolved carbon,major, and trace elements during spring flood periods on the Ob River     

Sergey N. Vorobyev  Oleg S. Pokrovsky  Larisa G. Kolesnichenko  Rinat M. Manasypov  Liudmila S. Shirokova  Jan Karlsson  Sergey N. Kirpotin 《水文研究》2019,33(11):1579-1594

Detailed knowledge of the flood period of Arctic rivers remains one of the few factors impeding rigorous prediction of the effect of climate change on carbon and related element fluxes from the land to the Arctic Ocean. In order to test the temporal and spatial variability of element concentration in the Ob River (western Siberia) water during flood period and to quantify the contribution of spring flood period to the annual element export, we sampled the main channel year round in 2014–2017 for dissolved C, major, and trace element concentrations. We revealed high stability (approximately ≤10% relative variation) of dissolved C, major, and trace element concentrations in the Ob River during spring flood period over a 1‐km section of the river channel and over 3 days continuous monitoring (3‐hr frequency). We identified two groups of elements with contrasting relationship to discharge: (a) DIC and soluble elements (Cl, SO₄, Li, B, Na, Mg, Ca, P, V, Cr, Mn, As, Rb, Sr, Mo, Ba, W, and U) negatively correlated (p < 0.05) with discharge and exhibited minimal concentrations during spring flood and autumn high flow and (b) DOC and particle‐reactive elements (Al, Fe, Ti, Y, Zr, Nb, Cs, REEs, Hf, Tl, Pb, and Th), some nutrients (K), and metalloids (Ge, Sb, and Te), positively correlated (p < 0.05) with discharge and showed the highest concentrations during spring flood. We attribute the decreased concentration of soluble elements with discharge to dilution by groundwater feeding and increased concentration of DOC and particle‐reactive metals with discharge to leaching from surface soil, plant litter, and suspended particles. Overall, the present study provides first‐order assessment of fluxes of major and trace elements in the middle course of the Ob River, reveals their high temporal and spatial stability, and characterizes the mechanism of river water chemical composition acquisition.  相似文献   

Impact of environmental factors on bacterial communities in floodplain lakes differed by hydrological connectivity     

《Limnologica》2016

We analysed total bacterial number and mean volume of cells at three sites in each of ten floodplain lakes in the Middle Basin of the Biebrza River, North-Eastern Poland to test bacterioplankton communities change according to the distance to the river. The composition of the bacterial communities was determined by fluorescent in situ hybridization method. Total number of bacteria in the lakes ranged from 4.0 to 7.48 cells × 10⁶ mL⁻¹ with dominance by Actinobacteria, the contribution of which was positively correlated with water level. Old river channels (side-arms) featured Alpha- and Gammaproteobacteria. The community of Betaproteobacteria was limited by concentration of dissolved organic carbon. Archaea, in spite of a minor role (<3.65% of DAPI-4′,6-diamidino-2-phenylindole) in the communities, showed a positive relation to floodplain lake isolation. Multivariate analysis demonstrated that bacterioplankton in riverine lakes was similar to that in rivers, while lakes with limited water exchange showed a similarity to fertile lakes. Water level and nutrients were among the factors determining bacterial community structure.  相似文献   

应用EOS/MODIS资料监测河西内陆河下游水库湖泊水域的变化   总被引：3，自引：0，他引：3  

杨兰芳 《干旱气象》2005,23(1):49-53

利用EOS/MODIS资料,对2004年春季至秋季间分布在甘肃省河西境内的2个面积最大的水库———红崖山水库、双塔水库和位于内蒙古额济纳旗的东、西居延海湖泊的水体面积进行监测计算,并与近年同期平均值进行了对比分析,结果表明疏勒河、石羊河及黑河流域下游的水库湖泊水体面积都有不同程度的减小。  相似文献   

Breeding in the freshwater crayfish paranephrops planifrons white   总被引：2，自引：2，他引：0  

C. L. Hopkins 《新西兰海洋与淡水研究杂志》2013,47(1):51-58

The breeding cycle of female Paranephrops planifrons is described. The incubation of eggs and young takes place between April and December and covers about 25–26 weeks. The winter population contains some apparently adult females which do not breed. The number of eggs laid increases with the size of the parent, and in the population studied varied from some 20 to 30 eggs at 17 mm carapace length to 150 eggs at 30 mm carapace length. After hatching the young pass through two moults while still attached to the parent.  相似文献   

Notes on laboratory rearing of juvenile spiny lobsters,jasus edwardsii (hutton) (crustacea: Decapoda: Palinuridae)     

Craig B. Kensler 《新西兰海洋与淡水研究杂志》2013,47(1):71-75

Post‐puerulus specimens of Jasus edwardsii (Hutton) have been successfully reared in the laboratory from the puerulus stage for periods of up to 12 months. The spiny lobsters were reared in concrete‐asbestos tanks measuring 2.4m × 37cm × 23cm. The tanks were supplied with a continuous flow of sea water and provided with constant aeration. Empty shells of paua (Haliotis iris Martyn) and rocks from the intertidal zone provided cover within the tanks.

Fresh mussel (Mytilus sp.) was preferred to all other foods tried in feeding experiments. The animals were fed every second day on opened mussels, and occasionally on fresh fish. The juveniles “grazed” actively on the calcareous algae (Corallina officinalis L.) present on the rocks.

The animals were extremely sensitive to pollution. To reduce pollution risks all sediments were removed from each tank, as the interstices between them were found to harbour uneaten food particles. Any uneaten foods were siphoned out every second day and each tank was thoroughly cleaned every six to eight weeks.

From a total of over 3,300 animals collected since November 1965, over 800 are presently being reared in the laboratory and various aspects of their ecology studied. The first step in raising larger adult sizes from juvenile stages in the laboratory is clearly possible.  相似文献   

Limnology of Opal Lake     

D. J. Forsyth  A. L. MacKenzie 《新西兰海洋与淡水研究杂志》2013,47(3):279-283

Opal Lake, a cold, acid lake on the central volcanic plateau of the North Island, New Zealand, had an average pH of 4.3 and was highly eutrophic. The biota was less diverse than in neighbouring near‐neutral waters. Macrophytes were rare; phytoplankton were mainly represented by the Chlorophyceae, and there were only 4 zooplankton species. The mean standing crop of macroinvertebrates was 6240 per square metre; this was higher than in other eutrophic lakes in the region and comprised more than 98% chironomid larvae represented by 4 species. Molluscs were absent. The fauna was more diverse than in more acid lakes of the .central volcanic plateau.  相似文献