湖泊渔业可持续发展的生态学基础及一个范例

从渔业与环境兼顾的角度出发作者认为湖泊渔业可持续发展的生态学理论基础是渔业生态学和渔业湖沼学. 前者是一门较为成熟的学科研究渔业对象的种群生态学渔产潜力最佳放流密度和规格以及科学的捕捞策略等. 后者研究渔业对湖泊生态系统生物多样性和水质的影响并确定最佳的渔业规模和渔业方式但尚未提出令人满意的理论和完善的实验方法今后应予充分重视. 长江中下游草型湖泊因为其优良的水资源和丰富的生物资源而成为我国内陆水体发展优质高效渔业的重要基地. 以湖北一个浅水草型扁担塘渔业实践为例作者着重强调生态学管理的如下方面1) 沉水植被是草型湖泊优质高效渔业持续发展的基础必须在合理利用的同时加以保护优化甚至重建使生物量和覆盖率保持和达到一定水平. 2) 食物链网的基础环节是渔业对象生长和繁衍的物质基础, 必须进行培育保护以提高其生产力从而为提高渔业产量打下物质基础. 3) 合理放养与捕捞策略是湖泊渔业生态系统良性循环的可靠保证应使高价值的种群规模保持较大水平的输出.     

Modeling uncertainties of reservoir flushing simulations

Every dam or barrage construction affects the watercourse and the retention of sediment that previously was carried by the river, which can lead to siltation of the reservoir and obstruction of water intakes over time, reducing their capacities. However, the information available regarding the effect of sediment and drawdown parameters, sediment management at reservoirs, as well as different equational approaches, is scarce. The current research aims to evaluate the effect of parameters associated with numerical modeling of sediment management in reservoirs considering scenarios with different drawdowns, transport equations, sediment size distributions, and thickness of the initial sediment layer. The case study of the Aimorés Hydropower Plant (HPP) is used, applying the Delft3D-FLOW model for two-dimensional modeling. All parameters influenced the volume of mobilized sediment, among which the initial layer thickness was the parameter that resulted in the greatest changes in simulated results. In general, the results show that the uncertainties in the input parameters outweigh the uncertainties between the techniques, which found large variations in results when evaluating the use of different transport equations. These results indicate the importance of proper estimation of model parameters for predicting effects with accuracy and the need for such studies before planning and management operations are evaluated to avoid environmental harm and energy waste.     

《长春市城市总体规划》图集的编辑制作

简要阐述了用MapGIS、CoreIDRAW两种软件结合制作《长春市城市总体规划》图集的设计、编制方法,采用图层模式有效管理地图集的数据．根据实践得出了一些经验和技巧。     

我国数字领海建设问题的几点思考

阐述了我国“数字领海(含专属经济区)”建设的重要性与迫切性;介绍了“数字领海”系统的功能、基本特征、技术支撑体系、信息采集方法、信息管理方法及信息更新方法;指出了“数字领海”系统建设中应注意的若干问题。     

甘肃省地震局高性能计算系统

高性能计算是现代科学研究、工程技术开发和大规模数据处理的关键支撑技术,在地震系统发挥着日益重要的作用。甘肃省地震局高性能计算集群系统由60个节点、采用40 GB InfiniBand网络互连组成,峰值计算速度达9.2万亿次/秒。作为地震系统重要的科技服务平台之一,为地震反演、数据分析、数值模拟等领域以及科研创新平台提供高性能计算环境。     

Development of a distributed hydrological model to facilitate watershed management

To facilitate precise and cost-effective watershed management, a simple yet spatially and temporally distributed hydrological model (DHM-WM) was developed. The DHM-WM is based on the Mishra-Singh version of the curve number method, with several modifications: The spatial distribution of soil moisture was considered in moisture updating; the travel time of surface runoff was calculated on a grid cell basis for routing; a simple tile flow module was included as an option. The DHM-WM was tested on a tile-drained agricultural watershed in Indiana, USA. The model with the tile flow module performed well in the study area, providing a balanced water budget and reasonable flow partitioning. The daily coefficient of determination and Nash-Sutcliffe coefficient were 0.58 and 0.56, for the calibration period, and 0.63 and 0.62 for the validation period. The DHM-WM also provides detailed information about the source areas of flow components, the travel time and pathways of surface runoff.

EDITOR A. Castellarin; ASSOCIATE EDITOR F.-J. Chang     

Natural flood management,land use and climate change trade-offs: the case of Tarland catchment,Scotland

A distributed hydrological model (WaSiM-ETH) was applied to a mesoscale catchment to investigate natural flood management as a nonstructural approach to tackle flood risks from climate change. Peak flows were modelled using climate projections (UKCP09) combined with afforestation-based land-use change options. A significant increase in peak flows was modelled from climate change. Afforestation could reduce some of the increased flow, with greatest benefit from coniferous afforestation, especially replacing lowland farmland. Nevertheless, large-scale woodland expansion was required to maintain peak flows similar to present and beneficial effects were significantly reduced for larger “winter-type” extreme floods. Afforestation was also modelled to increase low-flow risks. Land-use scenarios showed catchment-scale trade-offs across multiple objectives meant “optimal” flood risk solutions were unlikely, especially for afforestation replacing lowland farmland. Hence, combined structural/nonstructural measures may be required in such situations, with integrated catchment management to synergize multiple objectives.