アメリカにおける「サスティナブル・アグリカルチャー」の理解 : カリフォルニア州の実状から

Abstract

California is one of the most developed agricultural states in the United states of America. However the agriculture of California is far different from other states. Today, California's agriculture has the following distinguishing features; 1. crops grown are very diversified, 2. many of them are intensive, 3. yields per acre are considerably high, 4. the intensive and high yield crops are grown mainly in small and family farms, which account for more than sixty percent of total nummber of farms in the State. And, such featured California's agriculture is quite dependent on the followings; 1. replete irrigation systems, 2. large sized agricultural machine and facility systems, 3. massive inputs of petroleum energy and chemicals (fertilizers and agricultural medicines), 4. hiring of foreign cheap labours. However, california's agriculture has been so in pursuit of such "modern and economic systems" as above mentioned that it is seriously suffered from various problems. Main problems are as follows; 1. increase in the cost of irrigating, 2. accumlation of salt and selanium in the farmland's soil, 3. solidification of soil, 4. soil, water, air and agricultural product pollution with chemicals (fertilizers and agricultural medicines), 5. confusion of ecosystem in and around the area, 6. increase of the real wage for the foreign labours. In addition to the above mentioned problems, another point is the decrease of farmland coming from urbanization. Today, in California, many people share a concern with new agricultural systems which have good effects upon the environment, food safety, farm-worker safety, farm business, regional economy, and production cost, and will be formed through improvement of the current agricultural system. From the viewpoint of research and extension, this new agricultural systems should be approached broadly, such as from agronomy, soil and water sciences, entomology, animal science, engineering, genetics, food sciences, rural medical science, and agricultural economics. Such new agricultural systems as above mentioned are called generally "Sustainable agriculture" which was emerged in California. Objectives of the paper are to take a general view of California's agriculture and to understand "Sustainable agriculture" in detail and systematcally.