广西三江县北部以黄牛为转化动力的生态农业模式

Ecological Agriculture Model with Cattle as Transformation Power in Mountainous Area of Nothern Sanjiang County,Guangxi

该模式的生产路线是：草→黄牛→（牛栏肥料＋牛役＋牛肉）→粮食（主要是大米）＋鱼＋蔬菜＋棉花＋蓝靛等，将草转化为肉、粮食、鱼、蔬菜和布衣，黄牛是转化的动力，简称为“黄牛模式”，产生良好的经济、社会和生态效益。比较一些专家提倡在中国南方亚热带山地经营“以草换肉”的论述更深一层；与北方草原地带畜牧业生产模式通过牛、羊等，将草转化为肉和毛皮为最终产品不同；与中国南方广大平原农区传统农业生产模式：草→牛（主要是水牛）→（牛役＋牛肉＋纯牛粪）→大米等的生产路线比较，形同而意广。“黄牛模式”利用亚热带山地的草坡是常绿阔叶林地带的次生产物，资源有限，产量不稳定，草质量低。养牛只能小型分散、圈、放养结合。该模式是开放性系统，长期生产过程中对草资源的利用只索取无回归，系统失调，生产力下降。在典型的山地，它仍不失为一种有效的生态农业模式。因此必需根据系统中各个环节的性质和特点进行改良，才能提高生产力和经济效益。

The production line of the model works as: grass→cattle→(cattle pen manure+power cattle+beef)→grain(mainly rice)+fish+vegetable+cotton+indigo, etc. Cattle is the power of transforming grass into food and clothing. It is refered to as “Cattle model”. The model gives good economic,social and ecological benefits. It has deeper meaning than the model of “exchange meat with grass” proposed by specialists for subtropical mountainous area in south China. It is different from the model of transforming grass into meat and leather through cattle and sheep in north China,and it has wider meaning than the model, grass→water buffalo→(power buffalo+beef+cow dung)→rice, in the plain area of south China.The “cattle model” utilizes the limited mountainous grass resources of secondary forest forming from subtropical evergreen broad leave forest, Those grassland are low in quality and unsteady in yield. Cattle are raised in the combination way of small sized and scattered grazing and breeded in pen, which is an open system of unsustainable production.Therefore,measures of improvement must be taken for increasing the production capacity and economic benefit of the grass land and for the sustainable development of mountainous eco agriculture according to the characteristics of each link in the system.