A Risk-Based Multi-Criteria Decision Analysis Approach to Evaluating Transboundary Water Development—The Case of Lower Mekong River Basin

The Lower Mekong River basin (LMB) covers the lower part of the Mekong river basin, including Laos, Thailand, Cambodia and Vietnam. Due to numerous pressures from high population growth and intensive hydropower development, the LMB has been facing significant challenges concerning its biodiversity and ecosystem. In 2017, Mekong River Commission (MRC), an intergovernmental organisation founded in 1995 among LMB countries, established the Council Study, which analysed the impacts of water development scenarios concerning the environmental, socioeconomic aspects of the LMB. This paper explores the nature of risks to the LMB water development and subsequently evaluates LMB’s water development scenarios described in the Council Study by using a multi-criteria decision analysis (MCDA) method. MCDA method has been widely applied in the field of water resource management in order to assist the decision-making process by systematically evaluating a certain number of alternatives against well-selected criteria through a preference rating scheme. By implementing a risk-based comprehensive assessment of the LMB transboundary water, this study provides insights into the impacts of the increasing risks to the ecosystem and human beings on the water development of the basin over time, which assists to change the awareness and the perspective toward humans’ risks and transboundary river ecosystem of decision-makers. This paper provides valuable recommendations for MRC to improve their policy concerning benefit-sharing scheme, water planning and risk mitigation strategies.

Building Long-term Mechanism of Water Conservancy Development Based on Trust in Rural Communities

Current situations of water conservancy development in China include:there is serious water shortage and pollution;total water reservoir capacity is large but most are dangerous reservoirs;water is widely distributed and directly serves the masses;business is comprehensive and many fields are involved;projects include public welfare and operating types;great regional difference and problems are varied;utilization methods are extensive and water environment is vulnerable.Based on these situations,this paper analyzes the public goods feature of water resource facilities and management mechanism,and points out that water conservancy development should not merely depend on the market force.Then,it discusses that the influence and trust of transformation period on the whole social members are requirements of new harmonious rural communities,and expounds the necessity of trust for building long-term mechanism for water conservancy development.Finally,it presents policy suggestions:trust is closely connected with benefits of every person,thus developing community trust should begin with every individual;building long-term mechanism for water conservancy development should rely on cultivating highly trust-based rural community shared values.

WATER RESOURCES DEVELOPMENT IN CHINA

The sustainable development of water resources is of vital importance to the maintenance of survival environment on which people rely for existence. A brief review is given on the characteristic features of water resources, the present status of water resources development and some major water conservancy projects under construction or in contemplation in China. Finally, the prospect of water resource development in

Still Water Runs Deep:On Practices of Innovative Development in People-to-People Diplomacy of Henan

In recent years,Henan sticks to the points of General Secretary Xi Jinping,makes full use of its rich resources and relations,makes efforts to deepen friendship with people around the world,promotes relations with foreign countries,pushes

Effects of hydroperiod duration on developmental plasticity in tiger frog （Hoplobatrachus chinensis） tadpoles

While developmental plasticity can facilitate evolutionary diversification of organisms, the effects of water levels as an environmental pressure on tiger frogs remains unclear. This study clarifies the relationship by studying the responses of tiger frog （Hoplobatrachus chinensis） tadpoles to simulated hydroperiods （i.e., constant low water levels, constant high water levels, increasing water levels, decreasing water levels, rapid changes in water levels and gradual fluctuations in water levels） in a laboratory setting. ANOVA analysis showed that none of the water level treatments had any significant effect on the total length, body mass, or developmental stages of H. chinensis tadpoles half way through development （11 days old）. Tadpoles raised in rapidly fluctuating water levels had protracted metamorphosis, whereas tadpoles raised under low and gradually fluctuating water levels had shortened metamorphosis. None of the water level treatments had a significant effect on the snout-vent length （SVL） or body mass of H. chinensis tadpoles at Gosner stage 42, or on the body mass of tadpoles at Gosner stage 45. However, the＇ tadpoles raised in high levels and rapidly fluctuating water levels, significantly larger SVL at Gosner stage 45, while ones under gradually fluctuating water levels had smaller SVL than the other groups. Time to metamorphosis was positively correlated with body size （SVL） at metamorphosis in H. chinensis tadpoles. H. chinensis tadpoles under constant low water level had the highest mortality rate among all the treatments （G-test）. Moreover, ANOVA and ACNOVA （with body length as the covariate） indicated that water levels had no significant effect on either the morphology （i.e. head length, head width, forelimb length, hindlimb length and body width） or the jumping ability of juvenile H. chinensis. These results suggest that the observed accelerated metamorphosis and high mortality of H. chinensis tadpoles under decreasing water level treatment was driven by density-induced physical interaetions among increasing conspeeifics.

Diel vertical migration of the copepod Calanus sinicus before and during formation of the Yellow Sea Cold Bottom Water in the Yellow Sea

To understand the effects of the Yellow Sea Cold Bottom Water （YSCBW） on the diel vertical migration （D- VM） of the copepod Calanus sinicus, we surveyed vertical distribution of C. sinicus at a fixed station in the Yellow Sea before （spring） and during （summer） formation of the YSCBW. Cold water （〈10℃） was observed in the bottom layer when the water column was thermally stratified in summer, but the water column was thermally well-mixed in spring 2010. Samples were collected from five different layers at 3-h intervals using an opening-closing net. Adult females （1-155 ind./m3） showed a clear normal DVM pattern throughout the entire water column in spring, whereas adult males did not migrate. DVM of copepodite V （CV） individuals was not clear, but the maximum abundance of CI-CIV occurred consistently in the upper 10-20 m layer, where there was a high concentration of chlorophyll-a （Chl-a） （0.49-1.19μg/L）. In summer, weak DVM was limited to cold waters beneath the thermocline for adult females （〈30 ind./m3）, but not for adult males. The maximum abundance of CI-CIV also occurred consistently in the subsurface layer （20-40 m） together with high concentrations of Chl-a （0.81-2.36 μg/L）. CV individuals （1-272 ind./m3） moved slightly upward noc- turnally to the near-surface layer （10-20 m）, where the average temperature was 25.74℃, but they were not found in the surface layer （0-10 m; 28.31℃）. These results indicate that the existence of the YSBCW affected food availability at depth and the vertical temperature distribution, leading to variation in the amplitude and shape of stage-specific vertical distributions （CI to adults） in C. sinicus before and during the formation of cold waters in the Yellow Sea during the study period.

黄河三角洲微咸水灌溉对水稻产量的影响

如何提高黄河三角洲微咸水利用率,节约淡水资源是黄河三角洲盐碱地水稻产业发展的关键问题之一。以多个水稻品种为材料,比较了不同盐度、不同发育时期微咸水灌溉下产量相关性状的变化。结果表明,全生育期3 g/L和5 g/L盐度的微咸水灌溉均影响水稻产量,其中3 g/L微咸水灌溉主要影响了穗粒数和千粒重,而5 g/L微咸水灌溉影响是多方面的;全生育期3 g/L微咸水灌溉产量降低约10%,而5 g/L微咸水灌溉减产超过40%。在插秧返苗期3 g/L微咸水浇灌会降低成苗率,但一定程度上提高水稻的耐盐能力,降低盐胁迫对水稻产量的影响。相对其他时期,仅在分蘖期进行5 g/L微咸水灌溉对水稻产量的影响相对较小;孕穗灌浆期用微咸水灌溉严重影响水稻灌浆。因此,在当地淡水资源短缺的情况下,可以考虑在返苗期和分蘖期使用3 g/L的微咸水进行灌溉,但要适当增加该单位面积内苗数,缓解因成苗率降低造成的产量损失,而分蘖期可以适当采用高盐度微咸水灌溉,但不宜超过5 g/L,孕穗灌浆期微咸水盐度应严格控制在3 g/L以下。黄河三角洲地区微咸水资源的利用能够充分节约淡水资源,具有较好的经济和生态效益。

桂东南花岗岩崩岗土壤界限含水率空间变异及影响因素

界限含水率是土壤水理性质的重要参数,可表征土体状态随含水量变化而变化的能力,与崩岗土体稳定性密切相关,对预测降雨和崩岗侵蚀关系具有重要意义。本研究选取桂东南区活动型、半稳定型和稳定型3种花岗岩崩岗为研究对象,分析各崩岗土壤界限含水率空间变异规律并利用通径分析揭示其影响因素。结果表明:崩岗各部位土壤界限含水率在空间上存在差异,活动型和半稳定型崩岗土壤液塑限在崩壁上部有最大值(液限分别为54.45%和57.08%,塑限分别为32.84%和34.04%),洪积锥顶部有最小值(液限分别为35.39%和30.72%,塑限分别为21.92%和20.23%);稳定型崩岗崩壁下部土壤液塑限最小(液限为33.78%,塑限为22.47%);随着崩岗发育逐渐稳定,各部位土壤界限含水率总体呈增加趋势。黏粒、有机质、总孔隙度和毛管孔隙度与土壤液塑限及塑性指数呈极显著正相关关系,其中,总孔隙度对土壤液塑限的影响最显著。总孔隙度、黏粒、有机质、毛管孔隙度对界限含水率变化起主导作用,总孔隙度、黏粒和毛管孔隙度分别是土壤液塑限、塑性指数和液性指数的主要影响因子。此研究结果可进一步明确崩岗侵蚀危害并确定高侵蚀风险部位,为崩岗危害预防与治理提供相关理论支撑。

土壤类型及含水量对花蓟马蛹期发育及羽化的影响

基于花蓟马Frankliniella intonsa(Trybom)偏好土壤内化蛹的习性,研究不同土壤及含水量对花蓟马化蛹及羽化的影响,以期为花蓟马蛹控制技术提供重要依据。采集黏土、壤土和沙土3种土壤并在105℃条件下烘干,在3种土壤中添加纯水至其含水量达到3.00%、5.00%、10.00%、15.00%、20.00%和25.00%,随后将花蓟马老熟2龄若虫引入不同类型及含水量的土壤,观察其化蛹与羽化。土壤类型及含水量均显著影响了花蓟马的羽化,且2种因素之间交互作用显著(P<0.05)。在所有供试土壤中,随着土壤含水量的增加,花蓟马羽化率表现出先升高后降低的趋势。其中,花蓟马在含水量为10.00%沙土中羽化率最高,可达77.50%;在黏土中,当土壤含水量为15.00%时,花蓟马羽化率最高达63.33%;而在壤土中,当土壤含水量为15.00%和20.00%时,花蓟马的羽化率最高,分别为50.00%和47.50%。此外,研究发现花蓟马的羽化高峰在15.00%含水量的沙土中出现在第4天,而在其他含水量沙土以及所有含水量的黏土和壤土中其羽化高峰为第3天。土壤类型与含水量共同制约着花蓟马的化蛹及羽化,田间可以通过控制土壤湿度来干预花蓟马的化蛹及羽化。

甲状腺激素脱碘酶在孕哺期十溴联苯醚(BDE 209)暴露致子代小鼠神经发育毒性中的潜在作用

研究孕哺期BDE209暴露对母鼠胎盘和子代脑组织甲状腺激素脱碘酶（deiodinase,DI）基因表达的影响,及其在子鼠神经发育毒性效应中的作用。将75只雌性昆明小鼠随机分为对照组、低剂量组和高剂量组,暴露BDE20910 d后,与雄鼠合笼,每组选取怀孕时间相近（相差不过2 d）的8只母鼠孕期持续染毒至子鼠断乳。采用实时荧光定量PCR检测孕17～18 d胎盘、出生后60 d子鼠脑组织3种类型脱碘酶基因相对表达,利用Morris水迷宫评价出生后60 d子鼠学习记忆能力,测量第2、16、30和60天子鼠体重,观察孕哺期BDE 209暴露对子代生长发育的作用。结果显示,BDE 209对子鼠出生时体重未见明显影响,出生后30 d,高剂量BDE 209暴露组雌性子鼠体重显著低于对照组子鼠体重（p〈0.05）,而低、高剂量暴露组雄性子鼠体重均显著低于对照组子鼠体重（p〈0.05,p〈0.01）,出生后60 d,BDE 209对子鼠体重影响不明显。BDE 209暴露能够显著延长出生后60 d雌、雄性子鼠逃避潜伏期（p〈0.05或p〈0.01）。BDE209暴露显著降低母鼠胎盘中3种类型脱碘酶（主要是DI-3）基因表达（p〈0.05或p〈0.01）,同时,BDE 209暴露可诱导出生60 d后雄性子鼠脑组织中DI-1基因表达（p〈0.05或p〈0.01）,抑制雄性子鼠脑组织中DI-3基因表达（p〈0.05）,BDE 209暴露对出生后60 d雌鼠脑组织脱碘酶未见明显影响（p〉0.05）。研究结果表明,孕哺期BDE209暴露可能通过影响母鼠胎盘组织脱碘酶（特别是DI-3）基因表达,导致子鼠神经发育毒性效应-学习记忆能力障碍。