$ ^{*} $ Note: The shading in the legends represents the tree coverage rates (0-100%) per 1km square. Source: Geographical Survey Institute, Chiba University

considered to have continued due to the massive amount of nitrogen deposition, while there was an outflow of sulfur, considered to have accumulated in soil in the past from the atmosphere, to mountain streams. However, the situation at the moment will not directly affect human health and ecosystems.

Thus, the damages caused by acid deposition in Japan is still unclear at the moment. Impacts of acid deposition may become apparent in the future if the current level of acid deposition continues, since its impacts are considered to appear after a long time in general.

(b) Dust and sandstorms (DSS)

In recent years, the dust and sandstorms (DSS) that blow over from China and Mongolia have increased their scale, and China, South Korea, Japan and other nations share a common interest in dealing with such enlarged DSS. Although DSS had been considered as a natural phenomenon, there are indications that recent occurrences are influenced by anthropogenic factors, including overgrazing and the expansion of farmlands, and beginning to gain attention as a transboundary environmental issue.

## C Marine environment

In order to assess and monitor the conditions of the chronological change of the marine environment around Japan, Japan conducts marine environment monitoring programs, systematically collecting comprehensive data on water quality and bottom sediments and aquatic organisms. In FY2007 Japan conducted supplementary research in the western part of the Japan Sea that was researched in FY2004. The result showed higher concentrations of organotin and brominated flame retardant (specific indicator substance for organotin pollution source) were detected in the sediment compared to research results of the general offshore sea area. However, as a result of a simple risk assessment, a judgment was made that it will not affect human health. Japan will continue to conduct regular monitoring to see if any significant changes in the pollution condition should emerge.

In recent years, further deterioration of the environment and scenery including degradation of coastal functions and the ecosystem and the intensification of securing safe vessel navigation and damage to fisheries caused by marine litter including those originating from overseas has been pointed out.

## D Forest

The world’s forests now occupy approximately 30% of the earth’s surface, approximately 4 billion hectares. There has been a decrease of about 7.32 million hectares per year on average from 2000 to 2005, after taking out adjusting for the increased areas (about one fifth of Japan’s national land area). Particularly, African, South American and Southeast Asian from Asian region forests, where the tropical forests are located, have suffered a significant reduction in their size (Figure2-2). This deforestation and deterioration has serious impacts on global warming and loss of biodiversity.

Conversion to agricultural land, such as plantation development, an increase in non-traditional slash-and-burn agriculture, overharvesting of timber for fuel and forest fire are stated as causes of deforestation. In addition to these factors, inappropriate timber harvesting including illegal logging has caused deterioration of forests and all these factors have combined to make deforestation into a major issue.

## E Desertification

Desertification is defined by the United Nations Convention to Combat Desertification in Those Countries Experiencing Serious Drought and/or Desertification, Particularly in Africa as “the degradation of land in arid areas.” Arid areas occupy approximately 41% of the