Chapter ３　Water Environment Measure

　In closed water area such as Inner-bay and inland-sea which have contamination source around big city, the accomplishment of environment base is lower compared to other water area. In addition, substances such as nitrogen and phosphorous are inflow to the ocean which leads nutrient enrichment.
　There are many areas in the world where red tide due to nutrient enrichment emerges. Moreover, there are several areas where lack of oxygen emerges due to worsening of bottom sediment which leads to blue tide. To prevent these issues, it requires water quality conservation measure in closed water area. River water into the ocean contains less minerals because rain water doesn't remain in the land due to deforestation around the river of upper stream. When such river water goes into the ocean, seaweed in the ocean reduces due to lack of minerals in brackish waters. As a result, that leads sea desert. Seaweeds absorb nitrogen and phosphorous as fertilizer and contribute to water purification. Thus, the reduction of seaweeds facilitates nutrient enrichment which leads to red tide.
　Various coast areas are reside in a landfill to obtain industrial and transport area during high economic growth period. As a result wetland and seaweed bed disappeared. In such coast areas, it needs to conserve the remained wetland・seaweed bed as well as facilitate to recover damaged wetland・seaweed bed by projects based on natural recovering law and dredging.
　Also, in ocean where significantly worse bottom sediment, improvement of environment for living things and suppression of nutrient enrichment is carried out by dredging and overlaying sand.

　Daily wastewater and industrial water from river basin and city in coast are satisfied certain water quality standard because high advanced wastewater treatment facilities are installed due to the rise of the environment awareness and tightening of regulations of flow water quality. However, since river flow standard didn't regulate nitrogen and phosphorous and non point contamination matters increases, nutrient salts flow into the ocean thus that leads ocean contamination, nutrient enrichment, and red tide.
　Moreover, from increase of natural disaster due to abnormal climate and ruin forest, waste are into the ocean. Also, when industry accidents emerge, harmful matters go into the ocean. Therefore, various contamination matters go into the ocean, which leads ocean contamination and nutrient enrichment.
　As the measure, prevention contamination matter equipments should be installed in mouth of rivers or brackish waters, that reduce the amount of contamination matters to the ocean. In addition, it should facilitate the growth of seaweeds which leads the prevention of sea deserts. By these measures, Eco system of the ocean is conserved and we can get back rich ocean.

Prevention of contaminated water inflow

　In coast areas such as closed water area and inner bay, farming for fish and shellfish are conducted so it requires clean ocean.
　The feeds for faming fish, antibacterial agent, fish droppings can be the direct contamination source.
　At city development in coasts, harbor development and bridge piers works for trafic network construction, contamination water emerge which damage toward farming and fishery.
　As the measures, it enables to conduct ocean pollution prevention by installing CarbonFiber pollution prevention system around the contamination source.

Double contamination prevention system by CarbonFiber

　As the measure of red tide, reduction of nutrient salts can suppress nutrient enrichment. In the location before inflow to the ocean, it is important to facilitate water purification in wastewater treatment facility, rivers, lakes, and marshes and prevent inflow of nutrient enrichment. However, it is difficult to avoid non point source pollution, it is necessary to conduct direct measure in the ocean. In coast area, by getting back wetland and natural seashore natural purification function and recovering seaweed bed, organisms and seaweed can facilitate nutrient salts absorption. As the base, it is effective to install CarbonFiber artificial Kombu (MiraKombu). MiraKombu can facilitate the growth of seaweed and aquatic livings, as well as develop sea forest. Due to bioaffinity, various microorganisms and aquatic livings, shellfish such as ascidians and oysters live near MiraKombu. In addition, kombu and seaweed grows. By living things which live near CarbonFiber, Eco system in the ocean has good balance, which leads the reduction of nutrient enrichment as well as suppression of red tide.

Measure for red tide

　Tideland is located between the ocean and land, and it is fundamental place for food chain of Eco system and circulation of nutrient salts・matters. Moreover, tideland plays important rule for the place to live, water purification function, and organism production and transport place for foods. Thus, bad condition of tideland leads water purification issues.
　Tideland recovery should be conducted in both land area and ocean area. In land area, it should plant salt resistance plants or seaside plants absorbing nutrient salts. In tideland, for food circulation, crabs and shellfish should be grown, while fishes are in the ocean. This chain "organism circulation purification function" improves water purification.

　Tideland recovering technologies are following.
　　・Plant purification
　　・Shellfish effect
　　・Water purification by microorganisms attached to CarbonFiber
　　・Submerged breakwater
　　・Overlaying sand

　Seaweed bed works for living, hiding, and feeding place for young fish. Moreover, it becomes fishery place of abalones, turban shells, and sea eggs, as well as functions as water purification. Seaweed beds are classified depending on the plants such as Zostera marina, Sargassum, and Arame.
　However, currently, seaweed beds have disappeared due to nutrient enrichment, red tide, rising sea temperature, and harmful animals. That affect serve effect on Eco system in ocean.
　
　By recovering seaweed beds, it can achieve water purification and conservation of Eco system in the ocean that leads rise of fishery amount.
Seaweed bed recovering technologies are following.
　　・Development of seaweed grow place
　　・Planting seaweed
　　・Artificial seaweed by CarbonFiber which leads water purification and offers living place for seaweed.

 Artificial seaweed bed system by CarbonFiber （CFMA CarbonFiber Make Water Method Association）

Seaweed recovering by artificial CarbonFiber seaweed bed