亚热带山顶灌草丛的性质及其生态,经济效益

亚热带山顶灌草丛多分布于林区“假林线”以上的平缓山顶和山脊.其面积虽小,但分布广泛;被地形因素分割为孤岛状的各个山顶灌草丛群落之间,植物种类组成差异甚大,从而构成了多样化的植物群落类型;从植物生活型的分析,可窥见各群落具有垂直地带性的特点,反映着我国亚热带地区海拔1000m左右地段的气候状况,但也反映山顶局部气候因素及火烧等人为干扰因素的影响,故具有半地带性的性质;亚热带山顶灌草丛是山地森林或山顶矮林逆向演替的产物,具有其次生性与相对稳定性,是一种特殊的、与地形因素有关的遍途演替顶极.山顶气候温凉,水分条件好,应尽可能因地制宜地发展针叶林或针阔混交林,局部地段在确保水土的前提下适当发展小规模的季节性放牧,并培植三叶草、苜蓿、草木樨及某些禾本科牧草,这是建立人工草场的良好处所.

THE CHARACTER,ECOLOGICAL AND ECONOMIC EFFICIENCY OF THE SUBTROPICAL HILLTOP FRUTICETA-HERBOSA COENOSIA

The subtropical hilltop fruticeta-herbosa coenosia are common in plain hilltops and ridges above pseudotimberline with small area but wide distribution in subtropic of South China.Due to topographical separation,the hilltop fruticeta-herbosaes each has special floristic composition,therefore they form various phytocoenosia. An analysis on lifeform of hilltop fruticeta-herbosa coenosia shows that they possess the characteristics of vertical zonation, which reflect the subtropical climate of an altitude of 1000 metres above sea level in South China and the influence of partial ecological factors and accidental factor such as fire on hilltop. So it has a semizonal community property.This type is an outcome of mountain woods or hilltop elfin forest regressive succession with secondary community character and relative stability. It is a very special disclimax affected by topography. With cool climate and sufficient humidity, in the main, it will be reforest. Livestocks can be seasonally herded on hilltop on as mall scale.Hilltop is good for growing herbages of Trifolium, Medicago, Melilotus and some species of Gramineae for grazing.Therefore it is suitable for building an artificial grassland. There are few studies on this subject before.