Abstract The growing population of the world, which leads to increased production and consumption, result in an significent increase in solid wastes. This increase threatens environmental are human heath and harms the economics of countriesTo counteraction these negative outcomes, both the supply of wastes to the country's economy and the less use of natural resources can be considered. In this study, studies focus on the evaluation of industrial wastes in the geotechnical engineering are examined and discussed.

Abstract Fish like most seafood is a very rich source of protein and plays an important role in food security as a source of food for millions of people Worldwide. In many developing countries like Cameroon, fish is mainly for direct human consumption. This paper shows case lessons learnt from the field and generates discussion to further highlight existing challenges and opportunities to reach scale and impact of fish marketing  in Mbalmayo, Cameroon. As key findings, the study determined the typology of Fish market which varied from Smoked, dried, fresh life and dead fish, the sources of fish Sold in Mbalmayo markets which come from the river Nyong, the market actors (both men and women), the cost and price of fish sold in the markets and finaly the fish marketing chain and distribution channel.

Abstract  The purpose of this study was to consider the present status and challenges of aquatic animals inhabiting low-lying plains and mountainous regions in Japanese rural areas and to propose future conservation measures. My conclusions are as follows. On low-lying plains where modernizing agriculture such as farmland consolidation is developed, the development project is pointed out the problems from the viewpoint of the conservation of aquatic animals. My preference is for the irrigation water system to be pipelined and the drainage water system to be open channel. As for the drainage network, year-round water flow and the use of natural materials for canal beds are very important. Mountainous regions have suffered from depopulation, and maintaining terrace paddy fields has been difficult. To use agriculture to fulfill multiple functions, I propose zoning into agricultural land management areas, grass and forest management areas, and native forest areas. Appropriate adaptive management is required both on low-lying plains and mountainous regions. Additionally, it is significant to conserve aquatic animals in the watershed. The components of the watershed include farm ponds, dam reservoirs, lakes, flood control basins, paddy fields, rice terraces, rivers, irrigation canals, and drainage canals. It is also important to ensure water flow in the artificial systems around the paddy fields throughout the year. Using springs and groundwater during non-irrigation seasons is effective and efficient both on low-lying plains and in mountainous regions.