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191.
The loss of yields from agricultural production due to the presence of pests has been treated over the years with synthetic pesticides, but the use of these substances negatively affects the environment and presents health risks for consumers and animals. The development of agroecological systems using biopesticides represents a safe alternative that contributes to the reduction of agrochemical use and sustainable agriculture. Microalgae are able to biosynthesize a number of metabolites with potential biopesticidal action and can be considered potential biological agents for the control of harmful organisms to soils and plants. The present work aims to provide a critical perspective on the consequences of using synthetic pesticides, offering as an alternative the biopesticides obtained from microalgal biomass, which can be used together with the implementation of environmentally friendly agricultural systems.  相似文献   
192.
Environmental Science and Pollution Research - Pesticides might increase the production of reactive oxygen species (ROS). Dicamba (DIC) and 2,4-dichlorophenoxyacetic acid (2,4-D) are auxinic...  相似文献   
193.
Environmental Science and Pollution Research - In this work, it was analyzed the behavior of three commercial activated carbons with different textural and chemical properties to adsorb...  相似文献   
194.
Environmental Science and Pollution Research - Microplastics (MPs) are widely recognised as a contaminant of emerging concern in the marine environment. This work provides original data of the...  相似文献   
195.
Environmental Science and Pollution Research - A new set up of the integral mechanistic BIO_ALGAE model that describes the complex interactions in mixed algal-bacterial systems was developed to...  相似文献   
196.
介绍了循环序批式活性污泥反应器的工艺流程及设计参数、调试和运行情况,分析探讨了系统运行中出现的一些问题。稳定运行期间的检测结果表明,反应器对COD和NH3-N具有较好的去除效果,平均去除率分别达到86.2%和92.1%,但对TP的去除率有待提高。  相似文献   
197.
鲢鱼放养控制北京城市河湖水华试验研究   总被引:2,自引:1,他引:1  
介绍了利用鲢鱼控制北京城市河湖水华的试验研究,通过不同放养密度(0、17、51和103 g/m3)的现场围隔试验,对鲢鱼放养对水体水质和浮游生物的影响进行了分析.研究结果表明,鲢鱼放养使有鱼围隔中浮游生物量极低,从而使浮游植物基本不受浮游动物影响,而直接受鱼类影响;同时,中等密度(51 g/m3)的鲢鱼放养使水华蓝藻和微小藻的生长均得到了有效抑制,使藻类生物量最低.  相似文献   
198.
This paper introduces an integrated water management model at the industrial park level. It suggests four approaches to water management: first, direct water reuse among users; second, water reuse among users by blending with freshwater; third, water reuse between users and a wastewater treatment plant; and fourth, groundwater recharge by reclaimed wastewater or other feasible applications in order to optimize the overall water efficiency. The model results in a comprehensive management methodology for optimizing water resources within an industrial park, seeking potential water reuse among industries, and incorporating the size and cost of reclaimed wastewater delivery systems. A case study is employed to test the model’s feasibility. An economic analysis of the optimized water use network is also carried out, showing the potential water and cost savings.  相似文献   
199.
应用核磁共振技术找水是核磁共振技术应用的新领域,核磁共振找水是一种直接探测地下水的地球物理方法。本文介绍了在贫水地区一个指定范围内探测地下水例子。比较所做的三个僚共振测点的工作结果,确定出含中水情况较好部位,配合做了率对四极测探,其工作结果指示出一低阻区域,是地下水富集带。在设计的钻井位置钻探探打出了优质 下水,验证了核磁共振找水方法的推断结果。在对该磁共振找水方法研究和实践的基础上,指出:核磁共  相似文献   
200.
To achieve a safe and reliable drinking water supply, water producers need to manage a large range of risks regarding both water quality and quantity. A risk management approach where risks are systematically identified and handled in a preventive manner is promoted by the World Health Organization and supported by researchers and drinking water experts worldwide. Risk assessment is an important part of such a management approach, and a variety of tools for risk assessment are described in the literature. There is, however, little knowledge of how drinking water risk assessment is performed in practice, including which tools that are actually used. This study investigates the use of risk assessment tools, and the approach to risk management, on a local level in the Swedish water sector. It is based on interviews with key persons from a targeted selection of water producers. We find that the application of tools as well as the approach to risk assessment and management differs considerably between the water producers. The tools most frequently used are mainly the ones promoted or required by Swedish national organizations. Although many of the water producers have done some kind of risk assessment, most have not implemented a risk management approach. Furthermore, their knowledge of the concepts of risk and risk management is often limited. The largest challenge identified is to prioritize risk assessment, so that it is actually performed and then used as a basis for managing risk in a systematic way.  相似文献   
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