黄河三角洲海岸侵蚀现状及原因分析

阐述了黄河三角洲海岸侵蚀的现状及其特征,从自然因素和人为因素分析了海岸线侵蚀的原因。     

洞庭湖区枯水季节河流悬移质输沙量演变分析

为了确保各项水利工程建设对泥沙资料使用精度要求,同时优化泥沙测次,节约生产成本,对枯季河流含沙量进行分析,具有十分重要意义。本文以洞庭湖区南咀水文站的枯季悬移质输沙量变化进行分析。     

海水网箱养殖对沉积环境的影响

海水网箱养殖过程中未被生物摄食的饵料、养殖生物的排泄物及代谢物将对海底沉积环境产生一系列直接或间接的影响。主要污染物包括有机质、化学制剂和营养盐等。沉积物污染会造成溶解氧含量降低、沉积物中硫化物增加以及海底沉积速率增加,导致底栖生物群落发生变化,甚至底栖动物绝迹。部分网箱养殖的污染物质进入沉积环境后在生物、化学和物理作用下释放到海水中,造成二次污染。有些还会通过食物链富集威胁人类健康。     

城市湿地公园建造中底泥重金属生态影响及治理研究

城市湿地公园作为水体改造、水质提升、环境优化的重要载体．在城市生态环境建设中发挥着重要作用。本文以城市湿地公园营建过程的原水体底泥为研究对象,综述城市水体污染物的来源、特性和底泥中重金属污染研究,建议将污水截流、底泥控制和资源化、封装运输等工程和技术运用到水体的疏浚清淤．旨在为城市水体污染治理和湿地公园营建提供科学依据。     

河流泥沙数学模型的研究分析

泥沙数学模型是预测水沙运动和河床演变的重要手段之一。对一维数学模型、二维数学模型的基本原理、计算方法、关键技术处理等方面分别进行研究,分析黄河泥沙数学模型的应用,指出泥沙数学模型的发展方向。     

去除沉淀物树脂结构的试验研究

本介绍了离子交换树脂去除水中污染沉淀物的方法，提出了树脂结构对去除效果的影响，以及合成树脂工艺过程中相关参数的分析。     

当代和清代黄河治理比较研究

清代人民在二百多年治理黄河的实践中积累了丰富的经验和治河技术,但也有沉重的教训值得深思和借鉴。通过对清代黄河治理的思考,提出了当今黄河治理的策略。     

南方丘陵地区降雨径流和泥沙输出特征

在南方丘陵地区选择了2个小流域。进行野外9场降雨事件径流量、泥沙量随时问变化的试验。结果表明：受季节差异影响，不同月份径流量差异明显；低强度的降雨，当降雨过程停止后，径流流量反而有增大的趋势，强度较大的降雨。在中间时段降雨停止后。径流流量仍保持在一个稳定的值；在连续的低强度降雨后土壤含水量已经接近饱和，当遇到大强度的降雨后，地表径流在径流中所占比例较大；降雨量与悬浮泥沙含量相关程度较高。最大悬浮泥沙含量出现时间明显落后于径流流量出现峰值的时间。下降幅度要比径流流量下降幅度大。     

Changes in freshwater sediment microbial populations during fermentation of crude glycerol

BackgroundThis work studied how the exposure to an unusual substrate forced a change in microbial populations during anaerobic fermentation of crude glycerol, a by-product of biodiesel production, with freshwater sediment used as an inoculum.ResultsThe microbial associations almost completely (99.9%) utilized the glycerol contained in crude glycerol 6 g L⁻¹ within four days, releasing gases, organic acids (acetic, butyric) and alcohols (ethanol, n-butanol) under anaerobic conditions. In comparison with control medium without glycerol, adding crude glycerol to the medium increased the amount of ethanol and n-butanol production and it was not significantly affected by incubation temperature (28 °C or 37 °C), nor incubation time (4 or 8 d), but it resulted in reduced amount of butyric acid. Higher volume of gas was produced at 37 °C despite the fact that the overall bacterial count was smaller than the one measured at 20 °C. Main microbial phyla of the inoculum were Actinobacteria, Proteobacteria and Firmicutes. During fermentation, significant changes were observed and Firmicutes, especially Clostridium spp., began to dominate, and the number of Actinobacteria and Gammaproteobacteria decreased accordingly. Concentration of Archaea decreased, especially in medium with crude glycerol. These changes were confirmed both by culturing and culture-independent (concentration of 16S rDNA) methods.ConclusionsCrude glycerol led to the adaptation of freshwater sediment microbial populations to this substrate. Changes of microbial community were a result of a community adaptation to a new source of carbon.How to cite: Paiders M, Nikolajeva V, Makarenkova G, et al. Changes in freshwater sediment microbial populations during fermentation of crude glycerol. Electron J Biotechnol 2021;49. https://doi.org/10.1016/j.ejbt.2020.10.007     

Effect of water and sediment regulation on lower Yellow River

According to the results of the water and sediment regulations of the Yellow River in year 2002-2007, the effect of erosion and deposition on the lower reaches, the amount and distribution of erosion and deposition in the river mouth area, the adjustment of river regime, the effect of river regulation projects and changes of flowing capacity of the channel are analyzed. It is revealed that the water and sediment regulation is efficient to reduce deposition and improve the flowing capacity and the conditions of sediment transport.