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巴西于五十年代开始发展人工造林,至1960年方始有林业院校,1967年全国有人工林34.76万公顷,至1982年,全国人工林发展到431万公顷,增长10倍多。过去纸浆为进口国,现已为输出国,全国年产钢360万吨,40%用人工林烧炭作能源炼钢。发展林业的历史虽较短,但林木的生长水平及营林的技术措施,均达到当前世界第一流的水平。我们于1983年9—10月间,实地考察了戈亚斯州的巴西利亚、米纳斯吉拉斯州的具洛奥里藏特、圣埃斯皮里托州的维多利亚、圣保罗州的包鲁以及巴拉那州的库里提巴等5个州内的4个公司和2个林业研究站,考察地区的地理位置约为南纬16—25°,西经40—49°,4个林业(农林)公司共有林地面积260,500公顷,其中95%左右为单一的巨桉(Eucalyptus grandis)林,人员共7200人,林木每公顷的年生长量一般为30—40立方米,较高的可达50—60立方米,3年生的优势单株,胸径18.8厘米,每年采伐更新约为4000公顷,生产木材586万立方米,经济效益很高。巴西林木大面积速生丰产的原因,除气候(热带至亚热带)、土壤(沙壤土至沙土)等自然条件优越外,注重树种改良及营林技术,也是重要的因素。
In the 1950s, Brazil began to develop artificial afforestation. Until 1960, forestry institutions began to grow. In 1967, there were 349,700 hectares of man-made forests nationwide. By 1982, the growth of man-made forests nationwide had reached 4.31 million hectares, an increase of more than 10 times. In the past, pulp was an import country and now it is an exporter. The country produces 3.6 million tons of steel a year, and 40% uses plantation charcoal for energy production. Although the history of forestry development is relatively short, the growth of forest trees and technical measures for forest management have all reached the best in the world. In September-October 1983, we visited Brasilia in the state of Goias, Cerro Lloreuti in the Minas Gerais, Victoria in the State of Espirito Santo, Bauru and Curitiba in Parana, and four forestry research stations in two states. The geographical location of the study area is about 16-25 ° S, 40-49 ° W, and 4 The forestry (agriculture and forestry) company has a total area of 260,500 hectares of forest land, of which about 95% is a single Eucalyptus grandis forest and employs 7,200 people. The annual growth of forest trees per hectare is generally 30-40 cubic meters, Up to 50-60 cubic meters, the advantages of 3-year-old single plant, DBH 18.8 cm, annual harvesting updates about 4000 hectares, 5860000 cubic meters of wood production, high economic benefits. The reasons for the rapid and large-scale yield of Brazil’s forest trees are important factors in addition to natural conditions such as climate (tropical to subtropical) and soil (sandy loam to sandy soil), with emphasis on tree species improvement and silviculture.