在生命禁区抢险——记援藏干部马新国

2005年8月，日喀则地区定结县冰湖湖面明显扩大，并存在溃决险情。为确保安全，下游的群众已经撤出，住在临时搭建的帐篷里。为彻底消除冰湖对下游县城的威胁，确保群众安居乐业，发展县域经济，根据国家防总和自治区政府的指示精神，自治区防汛抗旱指挥部办公室决定对冰湖进行除险。     

水利工程建设中的遗产保护

从水工遗产保护的角度,详细介绍了旱涝灾后应急治理工程高邮境内里运河东堤沿线引水涵闸车逻闸除险加固过程中的建设方案、保护方案、施工工序、施工工艺等保护措施,以及水工遗产保护带来的效应,以期真正达到传承、保护、利用的目的 .     

岳城水库除险加固工程环境保护和水土保持管理体系及措施介绍

环境保护和水土保持措施对岳城水库除险加固工程建设而言,是非常重要的一项工件。加强施工过程中的环境保护和水土保持,是衡量一个国家级工程和文明工地综合素质的重要标准。简要介绍了除险加固工程中的环境保护和水土保持措施。     

基于土地利用/覆盖预测模型的昆仑山冰湖分布预测

开展冰湖时空分布预测研究，对预防冰湖溃决引发的灾害具有重要意义。基于GEE监督分类结果分析了2000～2020年昆仑山冰湖时空变化特征，探究了多准则CA-Markov、FLUS(Future Land Use Simulation)、PLUS(Patch-generating Land Use Simulation Model)3种土地利用/覆盖预测模型在冰湖预测中的适用性，得出最适宜昆仑山冰湖预测的模型，并基于此预测研究区未来冰湖变化趋势。结果表明：(1) 2020年，昆仑山地区冰湖数量及面积较2000年分别增长了39.25%和81.35%,冰湖空间分布呈现西多东少的特点。(2) 3种预测模型中，多准则CA-Markov模型在精度评价中表现最优，Kappa系数为0.86。(3)预测2025年冰湖面积及数量与2020年相比分别增加约6.54%、9.73%,2030年与2020年相比分别增加约14.59%、16.55%,未来昆仑山冰湖整体呈增长趋势，且东西部冰湖扩张差异将逐渐减小。     

兴安盟地区水库除险加固工程实施后的效益预测

介绍了兴安盟地区水库现状及水库除险加固工程建设情况，分析了水库除险加固工程实施前的效益，并对水库除险加固工程实施后的效益进行了预测。     

土坝上游坝址区清淤方法探讨

土坝上游坝址区清淤是水库除险加固施工中经常遇到的问题。本文根据临沂市三座大型水库除险加固的设计和施工经验，通过对土坝上游坝址区各种清淤方法的分析比较，提出了坝前无围堰水下清淤方法。并对其施工方法作了介绍。     

王宅水库除险加固工程质量控制与评价

基于层次分析和态势分析法,构建AHP-SWOT分析模型,对案例小型水库除险加固工程质量控制进行了分析,根据分析结果,提出采用W-T(应对威胁、克服劣势)防御性战略对王宅水库进行除险加固施工,同时基于模糊评价分析法,对除险加固施工后的工程质量进行了评价分析.结果表明:有35.2％的人对水库除险加固质量满意,水库总体除险加固施工质量基本符合要求.     

土坝上游坝址区清游方法探讨

土坝上游坝址区清淤是水库除险加固施工中经常遇到的问题。本文根据临沂市三座大型水库除险加固的设计和施工经验，通过对土坝上游坝区各种清淤方法的分析比较，提出了坝前无围堰水下清淤方法。并对其施工方法作了介绍。     

卢村水库大坝混凝土防渗墙施工与质量评析

日前混凝土防渗墙在安徽省水库大坝除险加固中应用较少。在卢村水库除险加固施工中，为了加强质量管理，确保工程质量，参建单位紧紧围绕质量目标，采取多种措施，在事前和事中对施工质量进行严格控制，取得了良好效果。从施工过程中的质量检查、检测结果和竣工检测结果综合分析，防渗墙施工质量总体较好，没有发生明显质量缺陷，达到了设计和规范要求。     

小型水库除险加固工程施工关键部位的质量控制

本文结合肥西县小型水库除险加固工程设计与施工状况，探讨了小型水库除险加固过程中关键部位的质量控制要点，对当前同类工程项目建设有借鉴意义。     

洪泽湖混合流数值模拟

本文通过构造一个二维开边界数值模式，对不同风情及出入湖流量组合情况下的洪泽湖混合流流态进行模拟研究，探讨其混合流特征。     

Feeding Ecology of Lake Whitefish in Lake Huron

We determined diet composition, feeding strategy, prey size, and effects of prey type on food weight and energy in stomachs for lake whitefish Coregonus clupeaformis in Lake Huron during 2002–04. Age-0 lake whitefish (73–149 mm TL) ate mainly large-bodied cladoceran zooplankton in the summer (July–mid September). Medium lake whitefish (≤ 350 mm TL excluding age-0) generally ate softbodied macroinvertebrates, especially Chironomidae larvae and pupae, in the spring (mid May-June). Zooplankton, if eaten, were generally most important in the summer. Molluscs were generally a minor part of medium lake whitefish diets. Large lake whitefish (> 350 mm) mainly ate molluscs, particularly quagga mussels (Dreissena bugensis), despite geographic differences in mussel abundance. Large-bodied crustaceans (Diporeia spp., Mysis relicta, Isopoda) were a minor part of large lake whitefish diets. Lake whitefish demonstrated a flexible feeding strategy, with individual specialization on some prey and generalized feeding on others. The size of benthic prey (Diporeia spp., Chironomidae, and Dreissena spp.) eaten increased with fish size and influenced the energetic value of prey for medium and large lake whitefish. The type of prey eaten affected the food and energy intake differently for each size class of lake whitefish. Age-0 lake whitefish that ate mainly zooplankton had more food and energy in stomachs than fish eating shelled prey or other macroinvertebrates. On the other hand, food weight in stomachs did not differ across prey groups for medium fish, but energy in stomachs was lowest for fish that ate shelled prey. For large lake whitefish, there was no difference in food weight or energy in stomachs for different prey groups.     

Maturity Schedules of Lake Trout in Lake Michigan

We determined maturity schedules of male and female lake trout (Salvelinus namaycush) in Lake Michigan from nearshore populations and from an offshore population on Sheboygan Reef, which is located in midlake. Gill nets and bottom trawls were used to catch lake trout in fall 1994 and 1995 from two nearshore sites and Sheboygan Reef. Each lake trout was judged immature or mature, based on visual examination of gonads. Probit analysis, coupled with relative potency testing, revealed that age-at-maturity and length-at-maturity were similar at the two nearshore sites, but that lake trout from the nearshore sites matured at a significantly earlier age than lake trout from Sheboygan Reef. However, length at maturity for the nearshore populations was nearly identical to that for the offshore population, suggesting that rate of lake trout maturation in Lake Michigan was governed by growth rather than age. Half of the lake trout males reached maturity at a total length of 580 mm, whereas half of the females were mature at a length of about 640 mm. Over half of nearshore males were mature by age 5, and over half the nearshore females matured by age 6. Due to a slower growth rate, maturity was delayed by 2 years on Sheboygan Reef compared with the nearshore populations. Documentation of this delay in maturation may be useful in deciding stocking allocations for lake trout rehabilitation in Lake Michigan.     

Potential Strategies for Recovery of Lake Whitefish and Lake Herring Stocks in Eastern Lake Erie

Lake Erie sustained large populations of ciscoes (Salmonidae: Coregoninae) 120 years ago. By the end of the 19^th century, abundance of lake whitefish (Coregonus clupeaformis) had declined drastically. By 1925, the lake herring (a cisco) population (Coregonus artedii) had collapsed, although a limited lake herring fishery persisted in the eastern basin until the 1950s. In the latter part of the 20^th century, the composition of the fish community changed as oligotrophication proceeded. Since 1984, a limited recovery of lake whitefish has occurred, however no recovery was evident for lake herring. Current ecological conditions in Lake Erie probably will not inhibit recovery of the coregonine species. Recovery of walleye (Sander vitreus) and efforts to rehabilitate the native lake trout (Salvelinus namaycush) in Lake Erie will probably assist recovery because these piscivores reduce populations of alewife (Alosa psuedoharengus) and rainbow smelt (Osmerus mordax), which inhibit reproductive success of coregonines. Although there are considerable spawning substrates available to coregonine species in eastern Lake Erie, eggs and fry would probably be displaced by storm surge from most shoals. Site selection for stocking or seeding of eggs should consider the reproductive life cycle of the stocked fish and suitable protection from storm events. Two potential sites in the eastern basin have been identified. Recommended management rocedures, including commercial fisheries, are suggested to assist in recovery. Stocking in the eastern basin of Lake Erie is recommended for both species, as conditions are adequate and the native spawning population in the eastern basin is low. For lake herring, consideration should be given to match ecophenotypes as much as possible. Egg seeding is recommended. Egg seeding of lake whitefish should be considered initially, with fingerling or yearling stocking suggested if unsuccessful. Spawning stocks of whitefish in the western basin of Lake Erie could be utilized.     

Nitrogen dry deposition to Lake Superior and Lake Michigan

Nitrate (NO₃^?) levels in Lake Superior have increased from historic levels of about 5?μM to its current concentration of about 25?μM. The atmosphere makes a substantial contribution to the nitrogen budgets for Lake Superior and Lake Michigan. This study provides a more well-defined estimate of nitrogen dry deposition rates derived from the measurement of over-water concentrations, and in situ meteorological measurements, which were input into the Resistance Model. We obtained a nitrogen dry deposition rate of [(3.41?±?2.26)?×?10⁷?kg?N/yr; (5.90?±?3.91)?kg?N/ha/yr] over Lake Michigan, and [(1.54?±?1.06)?×?10⁷?kg?N/yr; (1.87?±?1.27)?kg?N/ha/yr] over Lake Superior. Nitric acid (HNO₃), which originates from the combustion of fossil fuels, contributes 84% of the total nitrogen dry deposition to Lake Michigan; and 66% to Lake Superior. Ammonia (NH₃), which originates from agricultural activities and gasoline combustion, is the second highest contributor of nitrogen dry deposition to both lakes: contributing 13% to Lake Michigan and 32% to Lake Superior. The nitrogen dry deposition is approximately 68% of the nitrogen wet deposition over Lake Superior, and approximately 80% of wet deposition over Lake Michigan. The over-water dry deposition velocity of HNO₃ and NH₃ were also evaluated. We obtained morning deposition velocities of 0.099?cm/s for NH₃ and 0.095?cm/s for HNO₃; and afternoon values of 0.137?cm/s for NH₃ and 0.132?cm/s for HNO₃. Another key finding is that the atmospheric concentrations of nitrogen compounds near Lake Michigan and Lake Superior have decreased since 2003.     

太湖梅梁湾、贡湖套网格风生流数值模拟

对太湖梅梁湖、贡湖湖流进行套网格数值模拟。根据1998年8月太湖富营养化水质监测水文物理资料,绘制出梅梁湖、贡湖各站点位置分布图和其流速大小和方向。模拟计算与实测结果吻合较好,证明其套网格数值模型的建立是合理和有效的。分析结果表明,太湖各水域流速相差很大,近岸区域流速高于远岸区域,存在明显的近岸流。但流速值不大,即梅梁湖、贡湖和大太湖的水体交换量不大,通过流场分布可初步判断污染物质在水体中的扩散与迁移情况。     

Spatial Patterns in PCB Concentrations of Lake Michigan Lake Trout

Most of the PCB body burden in lake trout (Salvelinus namaycush) of the Great Lakes is from their food. PCB concentrations were determined in lake trout from three different locations in Lake Michigan during 1994–1995, and lake trout diets were analyzed at all three locations. The PCB concentrations were also determined in alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), bloater (Coregonus hoyi), slimy sculpin (Cottus cognatus), and deepwater sculpin (Myoxocephalus thompsoni), five species of prey fish eaten by lake trout in Lake Michigan, at three nearshore sites in the lake. Despite the lack of significant differences in the PCB concentrations of alewife, rainbow smelt, bloater, slimy sculpin, and deepwater sculpin from the southeastern nearshore site near Saugatuck (Michigan) compared with the corresponding PCB concentrations from the northwestern nearshore site near Sturgeon Bay (Wisconsin), PCB concentrations in lake trout at Saugatuck were significantly higher than those at Sturgeon Bay. The difference in the lake trout PCB concentrations between Saugatuck and Sturgeon Bay could be explained by diet differences. The diet of lake trout at Saugatuck was more concentrated in PCBs than the diet of Sturgeon Bay lake trout, and therefore lake trout at Saugatuck were more contaminated in PCBs than Sturgeon Bay lake trout. These findings were useful in interpreting the long-term monitoring series for contaminants in lake trout at both Saugatuck and the Wisconsin side of the lake.     

GPS?RTK?技术在青海湖容积测量中的应用

随着? GPS?的快速发展,RTK?测量技术也日益成熟,并逐步在测绘中得到应用.分析? GPS? RTK?技术在第一次水利普查青海湖容积测量中的应用,就? GPS? RTK?技术在水下地形测量中数据处理方法和野外测量优势进行探讨.在青海湖容积测量中的应用说明,RTK?技术改变了水下地形测量的作业模式,真正实现高精度、高效率,减轻了劳动强度,经过不断发展和完善,RTK?技术将改变测绘领域其他如控制测量、纵横断面测量、施工放样等的手段.     

魏源湖赋

荆楚古邑,宝庆隆中。乙卯降魔,治水劈山,扼河兴湖,名弘魏源。彰群贤壮志,汗青碧湖;酬先哲宏愿,水映金潭。登高远眺,雪峰逶迤,资水蜿蜒;凌空俯瞰,黛镜平铺,翡玉精嵌。南北隽秀,西洋江、小沙江,江湖连环;东西妖娆,白马山、九龙山,山峦迭嶂。高州温泉,闻名遐迩,荷田钟乳,玲珑剔透,