Effect of Human Activities on Overall Trend of Sedimentation in the Lower Yellow River,China

The Yellow River has been intensively affected by human activities, particularly in the past 50 years, including soil–water conservation in the upper and middle drainage basin, flood protection in the lower reaches, and flow regulation and water diversion in the whole drainage basin. All these changes may impact sedimentation process of the lower Yellow River in different ways. Assessing these impacts comprehensively is important for more effective environmental management of the drainage basin. Based on the data of annual river flow, sediment load, and channel sedimentation in the lower Yellow River between 1950 and 1997, the purpose of this paper is to analyze the overall trend of channel sedimentation rate at a time scale of 50 years, and its formative cause. It was found in this study that erosion control measures and water diversion have counteractive impacts on sedimentation rate in the lower Yellow River. Although both annual river flow and sediment decreased, there was no change in channel sedimentation rate. A regression analysis indicated that the sedimentation in the lower Yellow River decreased with the sediment input to the lower Yellow River but increased with the river flow input. In the past 30–40 years, the basin-wide practice of erosion and sediment control measures resulted in a decline in sediment supply to the Yellow River; at the same time, the human development of water resources that required river flow regulation and water diversion caused great reduction in river flow. The former may reduce the sedimentation in the lower Yellow River, but the reduction of river flow increased the sedimentation. When their effects counterbalanced each other, the overall trend of channel sedimentation in the lower Yellow River remained unchanged. This fact may help us to better understand the positive and negative effects of human activities in the Yellow River basin and to pay more attention to the negative effect of the development of water resources. The results of this study demonstrate that, if the overuse of river water cannot be controlled, the reduction of channel sedimentation in the lower Yellow River cannot be realized through the practice of erosion and sediment control measures.     

城市污水处理厂在工业污水管理中的地位

本文探讨了污水处理厂与源处理之间的相互影响和制约关系，目的是为有关部门进行水环境管理及做出科学决策提供依据．     

Agricultural recycling of treatment-plant sludge: a case study for a vegetable-processing factory

The present study evaluated the possibility of using the sludge produced by a vegetable-processing factory in agriculture. The sludge was amended with a soil mixture (i.e., a mixture of sand, soil, and manure) and was applied at 0, 165, 330, 495 and 660 t/ha to promote the growth of cucumbers. The effects of various sludge loadings on plant growth were assessed by counting plants and leaves, measuring stem lengths, and weighing the green parts and roots of the plants. We also compared heavy metal uptake by the plants for sludge loadings of 330, 495, and 660 t/ha with various recommended standards for vegetables. Our results showed that plant growth patterns were influenced to some extent by the sludge loadings. In general, the number of leaves, stem length, and dry weight of green parts exhibited a pronounced positive growth response compared with an unfertilized control, and root growth showed a lesser but still significant response at sludge loadings of 165 and 330 t/ha. The sludge application caused no significant increase in heavy metal concentrations in the leaves, though zinc (Zn) and iron (Fe) were found at elevated concentrations. However, despite the Zn and Fe accumulation, we observed no toxicity symptoms in the plants. This may be a result of cucumber's tolerance of high metal levels.     

微动力接触氧化法处理军营生活污水示范研究

将改变传统的机械充氧方式,通过增加水体与空气的接触面积,延长接触时间,进行自然充氧应用于微动力接触氧化法处理生活污水上。重点研究跌水曝气与接触氧化的耦合关系、停留时间与曝气量的耦合关系,形成跌水曝气接触氧化微动力分散式污水处理技术,研究微动力接触氧化挂膜规律和快速挂膜方法。并通过对技术参数的优化,在达到溶氧要求的同时,简化设计,提高其与后续工艺的对接性,降低工艺难度。     

Urban development and resource endowments shape natural resource utilization efficiency in Chinese cities

Improving the efficiency with which natural resources are utilized is an indispensable for achieving sustainable development and carbon neutrality. By analyzing the utilization efficiency of energy, water, and land, we established a comprehensive natural resource utilization efficiency index (NRUEI). We then calculated the 2016 index for 165 cities in China, and investigated what caused it to vary. We found three main results: (1) the NRUEI varied greatly across China and there were significant positive correlations between urban energy utilization efficiency (EUE), water utilization efficiency (WUE) and land utilization efficiency (LUE); (2) the NRUEI showed a significant positive correlation with a city's population size, economy (Gross Domestic Product (GDP)), and the level of urban social development (GDP per capita); (3) cities in East China have the highest natural resource utilization efficiency, while cities in Northeast China have the lowest. These results indicate that China's increasing urban development is associated with rising natural resource utilization efficiency and that the city's endowment of natural resources is an important factor affecting that efficiency. Further, the results showed that the determinants of a city's NRUEI differed in large and small cities. Lastly, our results suggest that improving EUE is key for improving NRUEI in urban China, and different efficiencies can be improved intertwined. A major takeaway of this study is that there is great potential for improving natural resource utilization efficiency in Chinese cities and we include city-specific suggestions for efficiency improvements.     

浅谈南阳市滨水型新农村生态建设

在滨水型新农村建设现状问题透析和生态农村理论与规划技术策略解读的基础上,对滨水型新农村建设规划的思路进行论述,从技术层面提出高效、和谐的理想农村形态,归纳得出具体的综合指导原则框架。     

莫斯科城市固体废弃物综合利用产业化概述

作者在多次参观考察莫斯科固体废弃物综合利用公司及其综合利用系列产品，并阅读了大量技术资料的基础上，初步总结了该公司固体废物综合利用形成产业化的经验，供我国环保同行借鉴参考。     

Remediation of s-triazines contaminated water in a laboratory scale apparatus using zero-valent iron powder

Atrazine, propazine and simazine were tested separately and in mixture by batch procedure in a laboratory-constructed apparatus. 3.75 l of a buffered s-triazines pesticide solution was treated at room temperature by 325-mesh zero-valent iron powder (ZVIP) (20 g/l). High performance liquid chromatography was used to separate by-products and study the decline in the pesticide’s concentrations. Results obtained show that the order of degradation was simazine, atrazine and then propazine. The half-lives (t_1/2) of the s-triazines pesticides are, respectively, 7.4, 9.0 and 10.6 min when they are treated separately, and 9.8, 11.2 and 13.7 min when they are treated together under the same conditions. The final by-product obtained after 50 min of contact of simazine with ZVIP shows a shift to longer wavelength in its UV spectrum. A similar phenomenon is shown for atrazine and propazine. Identical primary by-products are produced and subsequently degraded to 4,6-(diamino)-s-triazine, which seems to be the major by-product of the reductive treatment process. Pathways for the degradation of the studied s-triazines by ZVIP are proposed.     

污泥膨胀对MBR的影响试验研究

近年来,膜生物反应器(MBR)在废水处理领域得到了广泛的研究和应用,一般研究认为,膜的高效分离作用可以将微生物全部截留在反应器中,从而避免污泥膨胀对系统运行造成的不良影响。本文通过实验分析了膨胀污泥对MBR中污染物的去除效率。     

论鹤岗市生态环境利用与保护

对鹤岗市生态资源与环境现状进行分析;论述了生态环境保护与利用的重要意义;提出加强生态环境保护与利用的措施与对策。