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FLake模式摩擦速度参数化方案改进及其高原典型湖泊应用评估
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作者 宋兴宇 文莉娟 +1 位作者 苏东生 杜娟 《高原山地气象研究》 2024年第3期109-119,共11页
目前一维淡水湖模式(Freshwater Lake Model,FLake)在全球各类气候模型和再分析资料算法中被广泛应用,但其在青藏高原典型湖泊鄂陵湖的湖温模拟中效果欠佳,主要是模式内计算感热和潜热通量的摩擦速度参数导致的,而将通用陆面模式(Commun... 目前一维淡水湖模式(Freshwater Lake Model,FLake)在全球各类气候模型和再分析资料算法中被广泛应用,但其在青藏高原典型湖泊鄂陵湖的湖温模拟中效果欠佳,主要是模式内计算感热和潜热通量的摩擦速度参数导致的,而将通用陆面模式(Community Land Model version 4.5,CLM4.5)湖模块计算的摩擦速度参数值替换进FLake后,能够提升FLake模拟效果。本文根据CLM4.5湖模式的摩擦速度参数化方案,从理查森数计算公式、层结稳定性条件、摩擦速度计算公式三个方面改进FLake摩擦速度参数化方案,以鄂陵湖观测站资料作为驱动场,利用MODIS地表温度数据和站点实际观测资料评估FLake改进后的模拟效果。结果显示:改进后FLake可以更好地模拟湖泊热力状况,特别是在每年湖温达到最大值后的降温阶段,模拟的湖表温度、湖泊内部不同深度处的温度和净辐射更加接近实际观测值。相比于升温期,降温期感热和潜热通量的模拟值增大,对应温度模拟值低于改进前,并更接近实际观测温度,降温期湖温和净辐射的模拟精度有明显改善。 展开更多
关键词 参数化方案 摩擦速度 湖温 湖模式 鄂陵湖
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ERA5-Land青藏高原湖冰特征误差分析及FLake模式改进
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作者 杨柳依依 文莉娟 +2 位作者 王梦晓 苏东生 董靖玮 《高原气象》 CSCD 北大核心 2024年第5期1125-1137,共13页
青藏高原上湖泊众多,其中大多数被季节性湖冰覆盖。湖冰对气候变化响应敏感,其生消过程会显著改变湖-气交换通量。而现有的高原湖冰长时间观测数据较少,需要利用湖冰再分析资料进行研究。但目前对ERA5-Land湖冰资料在高原的适用性及改... 青藏高原上湖泊众多,其中大多数被季节性湖冰覆盖。湖冰对气候变化响应敏感,其生消过程会显著改变湖-气交换通量。而现有的高原湖冰长时间观测数据较少,需要利用湖冰再分析资料进行研究。但目前对ERA5-Land湖冰资料在高原的适用性及改进方法还不甚清楚。因此,本文首先利用2010-2022年青海湖和鄂陵湖的湖冰观测数据,评估了ERA5-Land再分析资料对青藏高原典型湖泊湖冰特征的模拟能力。结果表明:ERA5-Land资料对青海湖和鄂陵湖的冰厚平均高估0.54~0.62 m,对封冻期天数高估约68 d·a^(-1)。其次对再分析湖冰数据误差来源进行分析,通过对比ERA5-Land和鄂陵湖观测资料及其各自驱动模式的模拟结果,得出误差主要来源于输出ERA5-Land湖冰数据的FLake一维湖泊模式。最后基于2010-2022年青海湖和鄂陵湖的MCD43A3地表反照率产品,利用其多年平均反照率和动态日均反照率改进了FLake模型,模拟冰厚平均偏差可分别减小85%和90%,封冻期天数的模拟偏差减小了约6d·a^(-1)和8d·a^(-1)。两种方法均可以改进FLake模型对湖冰的模拟效果,特别是对积雪覆盖时间较长的湖泊,动态反照率方法改进效果更明显。本研究揭示了ERA5-Land湖冰特征的主要误差来源为FLake模式中的湖冰反照率,并对该参数进行了改进,提高了模型对湖冰的模拟效果,可为提高ERA5-Land再分析湖冰数据在青藏高原典型湖泊的模拟精度提供参考。 展开更多
关键词 青藏高原 湖冰 ERA5-Land Flake模式 参数优化
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Evaluation of the WRF-Lake Model over Two Major Freshwater Lakes in China 被引量:1
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作者 Yuanyuan MA Yi YANG +1 位作者 Chongjian QIU Chenghai WANG 《Journal of Meteorological Research》 SCIE CSCD 2019年第2期219-235,共17页
This paper evaluates the performance of the Weather Research and Forecasting(WRF) model coupled with a lake scheme over the Lake Poyang and Lake Dongting regions. We choose several cases with different weather charact... This paper evaluates the performance of the Weather Research and Forecasting(WRF) model coupled with a lake scheme over the Lake Poyang and Lake Dongting regions. We choose several cases with different weather characteristics, including winter with/without precipitation and summer with/without precipitation, and conduct a series of experiments(without the lake model, with the default lake model, and with a calibrated lake model that adjusts the water absorption, extinction coefficients, and surface roughness length) for each case. The results show that the performance of the lake model is significantly affected by the weather conditions. For the winter with precipitation cases, the performance of the default lake model is even worse than without the lake model, but the calibrated lake model can obviously reduce the biases of 2-m temperature and dew-point temperature. Although the performance of the default and new calibrated models is intricate for other cases, the new calibrated model has prominent advantages for 2-m dew-point temperature. Moreover, a long-term simulation of five months also shows that the new calibrated coupled lake model performs better than the default one. These imply that the new calibrated coupled lake model is more suitable to be used in studies of the effects of Lake Poyang and Lake Dongting on regional weather and climate. 展开更多
关键词 atmosphere-lake coupled model lake Poyang lake Dongting calibration WEATHER characteristics
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A model study of the effect of weather forcing on the ecology of a meromictic Siberian lake 被引量:1
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作者 Igor G.PROKOPKIN Egor S.ZADEREEV 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第6期2018-2032,共15页
We used a Lake Shira numerical model to estimate the response of the ecosystem of a saline meromictic lake to variations in weather parameters during the growing season. The sensitivity analysis of the model suggests ... We used a Lake Shira numerical model to estimate the response of the ecosystem of a saline meromictic lake to variations in weather parameters during the growing season. The sensitivity analysis of the model suggests that compared to other external(nutrient inflows) and internal(spring biomasses of food-web components) factors, weather parameters are among the most influential for both mixolimnetic(phyto-and zooplankton) and monimolimnetic(purple sulfur bacteria, sulfur reducing bacteria and hydrogen sulfide) food-web components. Calculations with different weather scenarios shows how changes in the water temperature and mixing depth af fect mixolimnetic and monimolimnetic food-web components and the depth of the oxic-anoxic interface in a meromictic lake. When weather forcing stimulates an increase in the biomass of food-web components in the mixolimnion, it produces cascading effects that lead to three results: 1) a higher content of detritus in the water column; 2) a higher content of hydrogen sulfide in the monimolimnion; 3) raising of the oxic-anoxic interface closer to the water-air surface. This cascading effect is complicated by the negative correlation between two light dependent primary producers located at diff erent depths—phytoplankton in the mixolimnion and purple sulfur bacteria at the oxic-anoxic interface. Thus, weather conditions that stimulate higher phytoplankton biomass are associated with a higher detritus content and lower biomass of purple sulfur bacteria, a higher content of hydrogen sulfide and a shallower oxic-anoxic interface. The same weather conditions(higher wind, lower cloud cover, and lower air temperature) promote a scenario of less stable thermal stratification. Thus, our calculations suggest that weather parameters during the summer season strongly control the mixing depth, water temperature and the mixolimnetic food web. An effect of biogeochemical and physical interactions on the depth of the oxicanoxic interface is also detectable. However, intra-and interannual climate and weather effects will be more important for the control of meromixis stability. 展开更多
关键词 meromictic lake numerical model WEATHER FORCING sensitivity analysis stratifi CATION FOOD web
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Modelling Chorabari Lake outburst flood, Kedarnath, India 被引量:2
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作者 Mohammd RAFIQ Shakil Ahmad ROMSHOO +1 位作者 Anoop Kumar MISHRA Faizan JALAL 《Journal of Mountain Science》 SCIE CSCD 2019年第1期64-76,共13页
In this study, the Glacier Lake Outburst Flood(GLOF) that occurred over Kedarnath in June 2013 was modeled using integrated observations from the field and Remote Sensing(RS). The lake breach parameters such as area, ... In this study, the Glacier Lake Outburst Flood(GLOF) that occurred over Kedarnath in June 2013 was modeled using integrated observations from the field and Remote Sensing(RS). The lake breach parameters such as area, depth, breach, and height have been estimated from the field observations and Remote Sensing(RS) data. A number of modelling approaches, including Snow Melt Runoff Model(SRM), Modified Single Flow model(MSF), Watershed Management System(WMS), Simplified Dam Breach Model(SMPDBK) and BREACH were used to model the GLOF. Estimations from SRM produced a runoff of about 22.7 m3 during 16–17, June 2013 over Chorabari Lake. Bathymetry data reported that the lake got filled to its maximum capacity(3822.7 m3) due to excess discharge. Hydrograph obtained from the BREACH model revealed a peak discharge of about 1699 m3/s during an intense water flow episode that lasted for 10–15 minutes on 17 th June 2013. Excess discharge from heavy rainfall and snowmelt into the lake increased its hydrostatic pressure and the lake breached cataclysmically. 展开更多
关键词 GLACIER lake OUTBURST FLOOD GIS modelLING Snow Melt RUNOFF Kedarnath GLACIER lake
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Interaction between Downslope and Alongslope Processes on the Margins of Daihai Lake,North China:Implication for Deltaic Sedimentation Models of Lacustrine Rift Basin 被引量:12
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作者 YU Xinghe LI Shunli +3 位作者 CHEN Bintao TAN Chengpeng XIE Jing HU Xiaonong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期932-948,共17页
Daihai Lake, a modern lacustrine rift basin, located in Inner Mongolia, North China, serves as an important modern analog for understanding deltaic depositional processes in an active rift setting. Two of the deltas ... Daihai Lake, a modern lacustrine rift basin, located in Inner Mongolia, North China, serves as an important modern analog for understanding deltaic depositional processes in an active rift setting. Two of the deltas (Yuanzigou delta and Bulianghe delta) on the margins of Daihai Lake were surveyed to compare and contrast stacking patterns using aerial photographs, field trenching and sediment sampling. Shallow cores and trench data collected from the margins of Daihai Lake indicate that a variety of depositional processes have been active since Daihai Lake formed. Two 3-D sedimentation models which employ chronostratigraphic correlation technique were generated. The chronostratigraphic sedimentation models predict and represent the architectures and sand-body continuity of sediments. Stratigraphical coincidence of the broad sheeted drifts and channel erosion suggests a coupling between downslope and alongslope processes. Distributary mouth bars are prevalent in the front of deltas on steeper slopes due to the dominance of down-slope flows. On the contrary, the along-slope currents favor the development of distal bar deposits with sheeted sandbodies on gentle depositional slopes. This study provides an insight into the architecture of complex sedimentary facies associated with highlighting key differences between downslope flows and alongslope currents. The distribution of sand within these deltas is of particular interests, with applications in understanding the architecture of hydrocarbon reservoirs formed in lacustrine rift basin. 展开更多
关键词 downslope flows alongslope currents architectural element spatial extension model Daihai lake
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History, development and characteristics of lake ecological models 被引量:1
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作者 XuFL TaoS 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期255-263,共9页
This paper provides some introductory information on the history, development, and characteristics of various lake ecosystem models. The modeling of lake ecological processes began to gain importance in the early 1960... This paper provides some introductory information on the history, development, and characteristics of various lake ecosystem models. The modeling of lake ecological processes began to gain importance in the early 1960s. There are a number of models available today, with varying levels of complexity to cope with the variety of environmental problems found in lake environments, e.g. eutrophication, acidification, oxygen depletion, wetland management, heavy metal and pesticide pollution, as well as hydrodynamic problems. In particular, this paper focuses on lake eutrophication and wetland models, as well as addressing strategies appropriate for the design and development of reliable lake ecological models. 展开更多
关键词 lake ecosystem eutrophication model wetland model pollution model
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Formation Conditions and Sedimentary Model of Over-Flooding Lake Deltas within Continental Lake Basins: An Example from the Paleogene in the Jiyang Subbasin, Bohai Bay Basin 被引量:3
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作者 WANG Jian CAO Yingchang +1 位作者 LIU Huimin GAO Yongjin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第1期270-284,共15页
A large quantity of drilling core, paleontology, geochemistry and geophysics data revealed several features of the Jiyang subbasin during the deposition of the Ekl-ES4x members: (1) the paleotopography of the gentl... A large quantity of drilling core, paleontology, geochemistry and geophysics data revealed several features of the Jiyang subbasin during the deposition of the Ekl-ES4x members: (1) the paleotopography of the gentle slope belt had an extremely low gradient; (2) the paleoclimate frequently alternated between dry and wet periods in a generally arid setting; (3) there was strong weathering around the periphery of the basin; (4) the lake was very shallow; (5) the lake level frequently rose and fell; and (6) the sedimentary environment of the gentle slope belt was an over- flooding lake. All of these factors provided favorable geological conditions for the development of an over-flooding lake delta. The lithologies of the continental over-flooding lake delta deposits are complex and diverse. The compositional maturity is moderate to low, and the grain size distribution curves and sedimentary structures indicate the presence of both gravity and traction currents. The sedimentary microfacies associations consist of a combination of ordered superposition of flood channels, distributary channels and sheet sands. The delta exhibits a weak foreset seismic reflection. The over-flooding lake delta deposits are laterally extensive. The sandstone content is high, and the individual sandstone beds are thin. The flood channel and distributary channel deposits exhibit evidence of bifurcation and lateral migration. The distribution of the sandbodies and the oxidation color of the mudstones provide evidence of cyclic deposition. The paleoclimate was the dominant factor controlling the development of the over-flooding lake delta. Due to the frequently alternating wet and dry paleoclimates, the over-flooding lake delta is characterized by the development of a broad upper plain and a lower delta plain. The upper delta plain is characterized by flood channel deposits, whereas the lower delta plain is represented by distributary channel deposits. The transition zone is characterized by the interaction of flood channels and distributary channels. Due to fault activity, the sandbodies of the over-flooding lake delta were juxtaposed against hydrocarbon source rocks, which was favorable for the development of lithologic reservoirs or structural-lithologic reservoirs. The lower delta plain deposits comprise the most favorable reservoirs. 展开更多
关键词 Jiyang subbasin continental basin over-flooding lake delta sedimentary model oil andgas exploration
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Evaluation of SWAT Model performance on glaciated and non-glaciated subbasins of Nam Co Lake, Southern Tibetan Plateau, China 被引量:1
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作者 Muhammad ADNAN KANG Shi-chang +3 位作者 ZHANG Guo-shuai Muhammad Naveed ANJUM Muhammad ZAMAN ZHANG Yu-qing 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1075-1097,共23页
This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau... This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau, two subbasins having catchment areas of 59 km^2 and 388 km^2, respectively. The scores of examined evaluation indices(i.e., R^2, NSE, and PBIAS) established that the performance of the SWAT model was better on the monthly scale compared to the daily scale. The respective monthly values of R^2, NSE, and PBIAS were 0.94, 0.97, and 0.50 for the calibration period while 0.92, 0.88, and -8.80 for the validation period. Glacier melt contribution in the study domain was simulated by using the SWAT model in conjunction with the Degree Day Melt(DDM) approach. The conjunction of DDM with the SWAT Model ensued improved results during both calibration(R^2=0.96, NSE=0.95, and PBIAS=-13.49) and validation (R^2=0.97, NSE=0.96, and PBIAS=-2.87) periods on the monthly time scale. Average contribution(in percentage) of water balance components to the total streamflow of Niyaqu and Qugaqie subbasins was evaluated. We found that the major portion(99.45%) of the streamflow in the Niyaqu subbasin was generated by snowmelt or rainfall surface runoff(SURF_Q), followed by groundwater(GW_Q, 0.47%), and lateral(LAT_Q, 0.06%) flows. Conversely, in the Qugaqie subbasin, major contributor to the streamflow(79.63%) was glacier melt(GLC_Q), followed by SURF_Q(20.14%), GW_Q(0.13%), and LAT_Q(0.089%). The contribution of GLC_Q was the highest(86.79%) in July and lowest(69.95%) in September. This study concludes that the performance of the SWAT model in glaciated catchment is weak without considering glacier component in modeling; however, it performs reasonably well in non-glaciated catchment. Furthermore, the temperature index approach with elevation bands is viable in those catchments where streamflows are driven by snowmelt. Therefore, it is recommended to use the SWAT Model in conjunction with DDM or energy base model to simulate the glacier melt contribution to the total streamflow. This study might be helpful in quantification and better management of water resources in data scarce glaciated regions. 展开更多
关键词 SWAT model NAM Co lake DEGREE-DAY MELT model Streamflow HYDROLOGICAL Response Unit
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Modeled response of talik development under thermokarst lakes to permafrost thickness on the Qinghai-Tibet Plateau 被引量:3
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作者 Feng Ling QingBai Wu +1 位作者 FuJun Niu TingJun Zhang 《Research in Cold and Arid Regions》 CSCD 2014年第6期521-530,共10页
Permafrost thickness under identical climates in cold regions can vary significantly because it is severely affected by climate change, topography, soil physical and thermal properties, and geothermal conditions. This... Permafrost thickness under identical climates in cold regions can vary significantly because it is severely affected by climate change, topography, soil physical and thermal properties, and geothermal conditions. This study numerically in- vestigates the response of ground thermal regime and talik development processes to permafrost with different thicknesses under a thermokarst lake on the Qinghai-Tibet Plateau. On the basis of observed data and information from a representative monitored lake in the Beiluhe Basin, we used a heat transfer model with phase change under a cylindrical coordinate system to conduct three simulation cases with permafrost thicknesses of 45 m, 60 m, and 75 m, respectively. The simulated results indicate that increases in permafrost thickness not only strongly retarded the open talik formation time, but also delayed the permafrost lateral thaw process after the formation of open talik. Increasing the permafrost thickness by 33.3% and 66.7% led to open talik formation time increases of 83.66% and 207.43%, respectively, and resulted in increases in the lateral thaw duration of permafrost under the modeled thermokarst lake by 28.86% and 46.54%, respectively, after the formation of the open taliks. 展开更多
关键词 permafrost thickness thermokarst lakes talik development lateral thaw modeling
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A COUPLING THREE DIMENSIONAL BAROCLINIC MODEL OF BIWA LAKE AIR-WATER SYSTEM
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作者 Zhang Limin Pu Peimin(Nanjing Institute of Geography & Limnology, Academia Sinica, Nanjing 210008People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第3期76-83,共8页
A numerical model coupling atmosphere with hydrodynamics is set up in this paper, and is applied in the experimental study of Lake Biwa. Some results are obtained as : (1) whatever (SSW) in sunimer or (NNW) in winer, ... A numerical model coupling atmosphere with hydrodynamics is set up in this paper, and is applied in the experimental study of Lake Biwa. Some results are obtained as : (1) whatever (SSW) in sunimer or (NNW) in winer, there exists a positive wind-stress curl over a lake; (2) in summer the positive wind-stress curi plays an important role to form circulation in a lake and produces a special temperature field corresponding to circulation, lower in the deep water, higher in the shallow water; (3) in summer, the hypothesis of initial horizontal inhomogeneous water temperature has little effiect on the results of simulation, and (4) in winter,there is no obvious circulation formed in the lake. 展开更多
关键词 air-water coupling model lake Biwa numerical simulaton
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Sedimentary Characteristics and Models of Paleo-salt Lake During Paleocene and Eocene in the Jiangling Depression of Central China
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作者 WANG Chunlian LIU Chenglin +3 位作者 XU Haiming YU Xiaocan XIE tengxiao ZHENG Yinghe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期253-253,共1页
1 Sedimentary Characteristics of Paleo-salt Lake In early sedimentary stages of Shashi formation,because of drought climate and the concentration of lake,a set of salt strata of hundreds of meters is developed in the ... 1 Sedimentary Characteristics of Paleo-salt Lake In early sedimentary stages of Shashi formation,because of drought climate and the concentration of lake,a set of salt strata of hundreds of meters is developed in the tension 展开更多
关键词 ROCK Sedimentary Characteristics and models of Paleo-salt lake During Paleocene and Eocene in the Jiangling Depression of Central China
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Thermodynamic Model of Uranium and Arsenic Accumulation in Saline Lakes
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作者 Olga GASKOVA Vitaly ISUPOV +1 位作者 Alexander VLADIMIROV Stepan SHVARTSEV 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期135-136,共2页
1 Introduction The attractiveness of Shaazgai-Nuur Soda Lake(pH9.2-9.4)as an alternative metal source is explained by the high concentration of dissolved uranium(~1 mg/l)due to the location of water drainage territory... 1 Introduction The attractiveness of Shaazgai-Nuur Soda Lake(pH9.2-9.4)as an alternative metal source is explained by the high concentration of dissolved uranium(~1 mg/l)due to the location of water drainage territory within the Tsagan- 展开更多
关键词 saline lakes URANIUM ARSENIC SORPTION thermodynamic model CALCITE goethite.
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Application of Bayesian regularized BP neural network model for analysis of aquatic ecological data—A case study of chlorophyll-a prediction in Nanzui water area of Dongting Lake 被引量:5
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作者 XU Min ZENG Guang-ming +3 位作者 XU Xin-yi HUANG Guo-he SUN Wei JIANG Xiao-yun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期946-952,共7页
Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of t... Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of the network were obtained. After the selection of input variables using stepwise/multiple linear regression method in SPSS i1.0 software, the BRBPNN model was established between chlorophyll-α and environmental parameters, biological parameters. The achieved optimal network structure was 3-11-1 with the correlation coefficients and the mean square errors for the training set and the test set as 0.999 and 0.000?8426, 0.981 and 0.0216 respectively. The sum of square weights between each input neuron and the hidden layer of optimal BRBPNN models of different structures indicated that the effect of individual input parameter on chlorophyll- α declined in the order of alga amount 〉 secchi disc depth(SD) 〉 electrical conductivity (EC). Additionally, it also demonstrated that the contributions of these three factors were the maximal for the change of chlorophyll-α concentration, total phosphorus(TP) and total nitrogen(TN) were the minimal. All the results showed that BRBPNN model was capable of automated regularization parameter selection and thus it may ensure the excellent generation ability and robustness. Thus, this study laid the foundation for the application of BRBPNN model in the analysis of aquatic ecological data(chlorophyll-α prediction) and the explanation about the effective eutrophication treatment measures for Nanzui water area in Dongting Lake. 展开更多
关键词 Dongting lake CHLOROPHYLL-A Bayesian regularized BP neural network model sum of square weights
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Development and application of a two-dimensional water quality model for the Daqinghe River Mouth of the Dianchi Lake 被引量:12
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作者 CHEN Qiuwen TAN Kui +1 位作者 ZHU Chuanbao LI Ruonan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期313-318,共6页
Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi L... Water quality models are important tools to support the optimization of aquatic ecosystem rehabilitation programs and assess their efficiency. Basing on the flow conditions of the Daqinghe River Mouth of the Dianchi Lake, China, a two-dimensional water quality model was developed in the research. The hydrodynamics module was numerically solved by the alternating direction iteration (ADI) method. The parameters of the water quality module were obtained through the in situ experiments and the laboratory analyses that were conducted from 2006 to 2007. The model was calibrated and verified by the observation data in 2007. Among the four modelled key variables, i.e., water level, COD (in CODcr), NH4+-N and PO43-P the minimum value of the coefficient of determination (COD) was 0.69, indicating the model performed reasonably well. The developed model was then applied to simulate the water quality changes at a downstream cross-section assuming that the designed restoration programs were implemented. According to the simulated results, the restoration programs could cut down the loads of COD and PO43-P about 15%. Such a load reduction, unfortunately, would have very little effect on the NH4^+-N removal. Moreover, the water quality at the outlet cross-section would be still in class V (3838-02), indicating more measures should be taken to further reduce the loads. The study demonstrated the capability of water quality models to support aquatic ecosystem restorations. 展开更多
关键词 two-dimensional water quality model parameter estimation restoration program evaluation Dianchi lake
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基于LMDI模型的土地利用碳排放时空差异及影响因素研究——以洞庭湖区为例 被引量:2
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作者 谭洁 刘琴 +2 位作者 唐晓佩 谭雪兰 刘沛 《地域研究与开发》 CSSCI 北大核心 2024年第1期160-166,共7页
运用碳排放系数法和对数平均迪氏指数(LMDI)模型,对1996—2020年洞庭湖区土地利用变化、土地利用碳排放时空差异及其影响因素进行分析。结果表明:(1)土地利用变化整体呈现出“三增三减”特征,建设用地和未利用地的变化程度较为显著,水... 运用碳排放系数法和对数平均迪氏指数(LMDI)模型,对1996—2020年洞庭湖区土地利用变化、土地利用碳排放时空差异及其影响因素进行分析。结果表明:(1)土地利用变化整体呈现出“三增三减”特征,建设用地和未利用地的变化程度较为显著,水域和草地次之,耕地和林地的变化程度最小。(2)总净碳排放量呈不断上升趋势,碳排放高值区由中部转向西、东、南部,土地利用碳足迹压力指数始终大于1,以0.54的年均增幅不断上升。(3)人均GDP、单位GDP用地面积和单位土地碳排放强度是影响土地利用碳排放的主要因子,人均GDP和单位GDP用地面积分别成为促进和减缓洞庭湖区碳排放量增长的主要因素。 展开更多
关键词 土地利用 碳排放 时空演变 影响因素 LMDI模型 洞庭湖区
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Analysis on Vegetation Succession Model and Process under Groundwater Exploitation in Subei Lake Watershed
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作者 WANG Cun-liang LI Ying +2 位作者 ZENG Lei ZHAO Gui-zhang YANG Feng 《Meteorological and Environmental Research》 2012年第10期56-59,共4页
[Objective] The study aimed to analyze vegetation succession process under groundwater mining conditions in Subei Lake watershed. [ Method] A succession model for vegetation and burial depth of groundwater level was c... [Objective] The study aimed to analyze vegetation succession process under groundwater mining conditions in Subei Lake watershed. [ Method] A succession model for vegetation and burial depth of groundwater level was constructed based on field survey, and it was used to pre- dict the vegetation succession rules and process according to the changes in burial depth of groundwater level in Subei Lake watershed under groundwater exploitation. [ Result~ In Subei Lake watershed, aquatic vegetation was most closely related to burial depth of groundwater level, fol- lowed by mesophytic vegetation, while psammophilous and xerophytic vegetation did not have obvious relation with burial depth of groundwater lev- el. When burial depth of groundwater level was small, dominant plants grew well, but they grew worse or died with the increase in burial depth of groundwater level. As the groundwater level fell constantly, burial depth of groundwater level went up, and vegetation succession would occur grad- ually from aquatic vegetation to mesophytic and xerophytic vegetation, from Carex L. and Iris ensata Thunb shoaly land to Achnatherum splendens shoaly lands, from Salix psammophila shrubs to Artemisia desterorum Spreng and Caragana korshinskii shrubs, and from Populus simonii to Salix matsudana. [Condusion] The research could provide scientific references for studying the relationship between groundwater resources and ecological environment in Subei Lake basin. 展开更多
关键词 Subei lake watershed GROUNDWATER VEGETATION Succession model Succession process China
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基于氡同位素的平原湖荡枯水期湖水地下水补排通量
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作者 卢小慧 吴潮峰 +6 位作者 龚绪龙 王梦瑶 王磊 张海涛 卫岩曈 严子豪 武鑫 《湖泊科学》 EI CAS CSCD 北大核心 2024年第3期939-950,共12页
水是人类生存之源,而湖荡被称为地球之“肾”,是河湖水系连接的关键缓冲节点,与人类生存和发展息息相关。长三角平原水系众多,河流纵横,天然湖泊与人工沟渠遍布,平原湖荡湖水与周边地下水的水力联系较为频繁,而地下水对湖泊水均衡贡献... 水是人类生存之源,而湖荡被称为地球之“肾”,是河湖水系连接的关键缓冲节点,与人类生存和发展息息相关。长三角平原水系众多,河流纵横,天然湖泊与人工沟渠遍布,平原湖荡湖水与周边地下水的水力联系较为频繁,而地下水对湖泊水均衡贡献尚不明确,对平原湖荡地下水赋存和运移规律的认识不足。本研究以苏州吴江区元荡湖为研究对象,选取氡同位素作为湖水和地下水水力交换过程的示踪剂,建立氡箱模型,揭示元荡湖不同区段与地下水的水力联系过程和补给关系,并通过水位动态验证分析湖水—地下水交互关系。枯水期元荡湖水位和氡浓度空间分布特征指示研究区内地下水向湖水排泄,其中以湖泊西侧较为明显,地下水入流补给的氡为7.137×10^(6)Bq/d,输入量源项占比为90%,地下水流入量为4540.801 m^(3)/d,地下水每日流入量对元荡湖水量的贡献率为2.551%。参数敏感性分析结果表明,风速与地下水^(222)Rn活度为特别敏感参数,取值差异较大时会导致计算误差急剧增大,改善测点布置和提高模型参数精度能有效提高模型计算结果的准确性和可靠程度。借助氡同位素示踪方法,建立湖泊氡箱模型,是研究平原湖荡内地下水补、径、排特征的有效方法。本研究在一定程度上加深了对平原湖荡区域水量均衡的认识,有助于了解平原湖荡水均衡和水循环机制,为平原湖荡水资源开发利用与环境保护提供数据支撑。 展开更多
关键词 氡同位素 湖泊氡箱模型 地下水 湖水 水力交换 元荡湖
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苏北高邮湖菹草(Potamogeton crispus)生长衰亡过程对水质与浮游植物群落的影响
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作者 张鑫 张又 +7 位作者 蔡平 刘荣坤 黎明杰 张晖 高俊峰 钱宝 蔡永久 燕文明 《湖泊科学》 EI CAS CSCD 北大核心 2024年第6期1681-1693,共13页
为探究菹草(Potamogeton crispus)生长、衰亡期对生态环境的效应,本文以南水北调东线源头调蓄湖泊——高邮湖为研究区域,通过分析湖泊水质及浮游植物群落随菹草生长衰亡过程的变化情况,揭示高邮湖菹草暴发下水环境状况变化。结果表明:... 为探究菹草(Potamogeton crispus)生长、衰亡期对生态环境的效应,本文以南水北调东线源头调蓄湖泊——高邮湖为研究区域,通过分析湖泊水质及浮游植物群落随菹草生长衰亡过程的变化情况,揭示高邮湖菹草暴发下水环境状况变化。结果表明:在菹草生长期水体透明度明显提高,且总氮浓度有较大程度的下降;而在菹草衰亡期,菹草生物量越高的区域水质越差。菹草在生长期对水环境起到一定的净化效果,而菹草衰亡降解会造成水质恶化。菹草生长期浮游植物密度和生物量显著低于衰亡期,生长期菹草高、中生物量区的浮游植物密度和生物量低于低生物量区,而在菹草衰亡期高、中生物量区的浮游植物密度和生物量高于低生物量区。冗余分析结果表明,pH、溶解氧、氨氮、硝态氮、总磷、高锰酸盐指数是菹草生长衰亡过程影响浮游植物群落结构的主要环境因子。分段结构方程模型模拟结果表明,菹草生物量可对浮游植物生物量产生直接效应,也可以通过改变环境因子对浮游植物生物量产生间接效应。 展开更多
关键词 沉水植物 植物腐烂 群落结构 冗余分析 分段结构方程模型 高邮湖
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陆相坳陷湖盆细粒沉积岩岩相类型及成因——以松辽盆地晚白垩世青山口组为例 被引量:3
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作者 孟庆涛 胡菲 +2 位作者 刘招君 孙平昌 柳蓉 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第1期20-37,共18页
页岩油是目前非常规油气研究的热点与难点。细粒沉积岩岩相类型及成因分析是页岩油“源储”特征研究及“甜点”预测的有效途径。松辽盆地青山口组细粒沉积广泛发育,是页岩油富集的有效层段。本文通过岩性、矿物成分、有机质丰度与沉积构... 页岩油是目前非常规油气研究的热点与难点。细粒沉积岩岩相类型及成因分析是页岩油“源储”特征研究及“甜点”预测的有效途径。松辽盆地青山口组细粒沉积广泛发育,是页岩油富集的有效层段。本文通过岩性、矿物成分、有机质丰度与沉积构造4个参数,将松辽盆地青山口组细粒沉积岩划分为6种岩相:高有机质泥纹层黏土质页岩(A)、中高有机质含细粉砂纹层长英质页岩(B)、中低有机质含粗粉砂纹层长英质页岩(C)、低有机质层状粉砂岩(D)、低有机质层状介形虫灰岩(E)和低有机质层状白云岩(F)。进一步从水动力学与有机质富集方面探讨了不同岩相类型的成因,并建立了相应的沉积模式。具体为:在风暴浪基面之下的静水、咸水环境、高湖泊生产力背景中,浮游藻类与黏土絮状物均匀悬浮沉降,形成贫富有机质黏土质纹层,沉积A岩相;在正常浪基面之下的相对静水(浪基面附近局部动荡)、半咸水环境、高湖泊生产力背景中,三角洲径流与洪流带来的细粉砂颗粒继续向湖盆中央搬运,经均匀悬浮沉降形成长英质纹层,间歇期悬浮沉降形成黏土质纹层,形成B岩相;正常浪基面之下,洪水携带粉砂级颗粒,顺着水下分流河道搬运至外前缘,以稳定性浊流的形式进入前三角洲,随流速逐渐降低,分异形成粗粉砂—细粉砂纹层,间歇期悬浮沉降形成黏土质纹层,形成C岩相;正常浪基面之下,三角洲前缘早期沉积物在阵发性浊流的作用下,滑塌至较深水区,形成D和E岩相;于正常浪基面与风暴浪基面之间,在相对干燥的气候背景下的咸水环境中,形成F岩相。 展开更多
关键词 陆相坳陷湖盆 细粒沉积 岩相 成因模式 页岩油 松辽盆地 青山口组
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