丘陵区用材林立体经营的初步研究

Three-dimensional Culture of Commercial Forests in a Hilly Region

为了探索丘陵区用材林立体经营模式，于1989年开始．在湖南省衡南县，开展了杉木幼龄林—山苍子—黄豆、杉木中龄林—绞股蓝、杉木中龄林—生姜、湿地松—棕榈—黄豆4个经营类型试验，进行了林中生态因子、小气候因子的测定，病虫害情况和土壤调查，6a的试验结果表明：4个经营类型都能改善林内的微域环境，提高土壤肥力．增强林分抵抗病虫害的能力，显著提高上层林木的生长量此外，立体经营在前期即能从中层树木和下层作物获得一定的经济效益，克服了传统林业生产周期长、早期无经济效益的缺点，能有效地发挥林业的练合效益.

The species disposition and structure types of some commercial forests in a hilly region of Hengnan county, Hunan province were studied from 1989 to 1994. Four three-dimensional culture types were formed. They are:young Chinese fir and Litsea cubeba and soy bean, middle Chinese fir and Gynostemma pentaphy llan, middle Chinese fir and ginger, Pinus elliottii and palm and soybean. The ecological factors and micro-climate factors were determined, and a survey of soil, plant diseases and insecl pests was conducted. Six years' experiments verified that each of the four culture types could improve the microclimate of the forests and the fertility of soil, enhance the stand's ability to resist diseases and insect pests, and raise the growth rate. Meanwhile, the three-dimensional culture types could make certain economic benefits from middle-level trees and lower-level plants in an earlier stage.