土坝涵管新型滚动式放水控制设施设计

贵州省20世纪50～70年代修建的大部分小型水库,其放水控制设施大多采用木塞堵涵管(或卧管)口的方式,目前木塞都已腐烂但又不易找到大直径木料来更换,因此对这些放水控制设施进行改造已成为迫在眉睫的问题.为此,设计了一种新型的涵管(或卧管)滚动式放水工艺,成功解决了困扰土坝涵管(或卧管)放水运行中的问题.

高压老空积水下侧小煤柱掘进防治水技术

阐述了在高压老空积水下侧留小煤柱掘进时,采取集中探放水、掘进中探放水相结合,套管控制放水量防治水技术,有效地消除了积水威胁,积累了防治高压老空积水的技术经验。

Co-benefits of Local Air Pollutants and Greenhouse Gas Reduction Achieved by Hydropower Development in Xizang(Tibet) Autonomous Region, China

Hydropower development in Xizang(Tibet) Autonomous Region plays a vital role in co-control of local air pollutants and greenhouse gas(GHG) in China. According to emission factors of local air pollutants and GHG of coal-fired power industry in different hydropower service regions, we estimate the effect and synergy of local air pollutants and GHG reduction achieved by hydropower development in Tibet, examine the main factors constraining the effect and synergy, using correlation analysis and multiple regression analysis. The results show that: 1) During the period from 2006 to 2012, the effect of local air pollutants and GHG reduction achieved by hydropower development in Tibet decreased as a whole, while the synergy increased first and decreased afterwards. 2) The effect and synergy of local air pollutants and GHG reduction achieved by hydropower development in Tibet vary significantly across different hydropower service regions. The effect based on emission levels of Central China power grid(CCPG) and Northwest China power grid(NCPG) was more significant than that based on emission level of national power grid(NPG) from 2006 to 2012, and the synergy based on emission levels of CCPG and NCPG was also more significant than that based on emission level of NPG from 2010 to 2012. 3) The main factors constraining the effect and synergy based on emission levels of NCPG and CCPG included SO2 removal rate and NOx removal rate, the effect and synergy based on emission level of NPG was mainly influenced by net coal consumption rate. 4) Transferring hydropower from Tibet to NCPG and CCPG, and substituting local coal-fired power with hydropower can greatly help to co-control local air pollutants and GHG, transform the emission reduction pattern of the power industry and optimize energy structure.

Field experiments on greenhouse gas emissions and nitrogen and phosphorus losses from rice paddy with efficient irrigation and drainage management

Greenhouse gas emissions,nitrogen and phosphorous losses through ammonia volatilization,leaching and surface drainage from rice paddy under efficient irrigation and drainage were analyzed based on field experimental data in order to reveal the eco-environmental impacts of efficient irrigation and drainage on rice paddy.The results showed that total methane emission from rice paddy under the controlled irrigation was reduced by more than 80% and total nitrous oxide emission increased by 15.9% compared with flooding irrigation.Seasonal comprehensive global warming potentials(GWP) of methane and nitrous oxide were 62.23 gCO2 m-2 for rice paddy under the controlled irrigation,reduced by 68.0% compared with flooding irrigation.Due to large reduction in seepage and surface drainages,nitrogen and phosphorous losses through leaching were reduced by 40.1% and 54.8%,nitrogen and phosphorous losses through surface drainage were reduced by 53.9% and 51.6% from rice paddy under efficient irrigation and drainage compared with traditional irrigation and drainage.Nitrogen loss through ammonia volatilization was reduced by 14.0%.Efficient irrigation and drainage management is helpful to mitigate greenhouse gases emission,nitrogen and phosphorus losses and their pollution on groundwater and surface water.

Analysis of the Water Environmental Capacity of Zhongba-Nyingchi Section of the Yarlung Tsangpo River

The Yarlung Tsangpo River,the longest river in Tibet,houses most of the population and economy in Tibet Autonomous province.Under the rapid development of economy and society in Tibet,the pollution in the Yarlung Tsangpo River basin has rapidly increased.Evaluating water quality and water environmental capacity is needed for water resource management in Tibet.This study used a single factor evaluation method to evaluate water quality of the Zhongba-Nyingchi section of the Yarlung Tsangpo River based on measured data of CODcr, NH3-N and TP in the study area.Based on these data,determinations of ideal water environmental capacity, emissions of pollutants and remaining water environmental capacity of the study area were made by a one-dimensional steady water quality model under either section-head control or cross-section control.The data indicate that most of the monitoring sections in the study area experienced good water quality.The three pollutants all had large remaining water environmental capacity generally,but TP exceeded state levels in the two upstream functional areas,and levels above state standards of CODcr and TP were found in several calculation cells of the two downstream functional areas.Therefore,emissions of pollutants need to be reduced to protect the water environment quality of the Yarlung Tsangpo River.