Risk Analysis And Eco-economic Losses Evaluation Of Water Hyacinth In Fujian Province

Water hyacinth(Eichhornia crassipes),which is originated from South America, has invaded the five continents such as Africa, Asia, North America, Oceania, Europe, is one of the top ten world's vicious weeds. In 1901, water hyacinth was introduced into China as one kind of pig feed, causing China's economic losses 10.0 billion annually. Water hyacinth has been distributed in North, East, Central and South China's at the end of the late 20th century, including 19 provinces (autonomous regions and municipalities). It seems to be an increasing number of the river blockage is caused by the spreading water hyacinth, which affects the shipping, aquaculture, hydropower, agricultural irrigation seriously and reducing the water quality and the mining of water resources; the accumulation of heavy metals disorders the well-balanced elements circulation; and provides the habitat for bacteria, which is harmful to animals and plants and human health. In Fujian, water hyacinth spread over 25% of the fresh. This is not only causes great troubles to the shipping, aquaculture, hydropower, agricultural irrigation, but also brings a threat to the biological survival potentially, causing enormous ecological and economic loss.This study aims to combine the biological characteristics of water hyacinth with its distribution in other countries or regions of the world. Making assessment of the economic losses caused by water hyacinth invasion in Fujian province and making an overview of water hyacinth control or the integrated prevention and comprehensive utilization of water hyacinth.This study is divided into five parts, the first part is the document commentary of the pest risk analysis, the assessment of economic loss on pest, the ecological and economic assessment of the loss caused by water hyacinth; The second part describes the biological characteristics of water hyacinth, the distribution of water hyacinth in the world and its adverse effects; the third section looks at the introduction of the Australian weed risk assessment system and makes the use of it to assess the risk of water hyacinth in Fujian; the fourth part aims to estimate the economic losses of water hyacinth in Fujian ; The fifth part is the water hyacinth protection and the integrated utilization.Among them, the third and fourth sections are the main parts of the study and also the parts of the main result of this study. The third section uses the Australian weed water hyacinth evaluation system to assess the risk in Fujian, which scores 23 points, the sub-environment system scores 12, agricultural system scores 3 points. According to Australian weed risk assessment system ,we can divide the risk into three levels:To accept import(<1 score);Reject import(>6 scores); Further assess whether the species as potential invaders(1～6 socres).Thus, we can be told that water hyacinth is the strictly restricted access weeds, which tends to belong to the environmental weeds, while it needs the further assessment to decide whether it is belong to the agricultural weeds. The fourth section, with the reference to the present documents, looks at the protection methods and cost control of water hyacinth, the spreading area of water hyacinth in Fujian, the indirect economic losses accounting of the environmental impact, etc., making the assessment of the economic losses on the water hyacinth invasion of Fujian, which results in approximately 1.04 billion yuan.