南方水田地区自然条件极为复杂,河流湖泊錯综分布,丘陵山地起伏重叠,耕地分散,坡陡田小,道路狭窄,陆路交通极为不便。除长江、珠江及几个较大湖泊地区有少数連片田块之外,一般水田在平原三、五亩为多数;丘陵山区水田田块則更小,一、二亩占很大比例。 这一地区水田土壤质地多属粘砂和粘壤质水稻土,在长期潴育之下,土壤物理机械属性变化幅度 The natural conditions in the southern paddy fields are extremely complicated. The rivers and lakes are intricately distributed, the hills and valleys overlap, the arable land is scattered, the steep slopes are small, the roads are narrow, and land transportation is extremely inconvenient. In addition to the Yangtze River, the Pearl River and several larger lakes there are a few contiguous plots, the general paddy fields in the plains three or five acres for the majority; hilly hills paddy fields are smaller, one or two acres account for a large proportion. Soil paddy field in this area mostly belong to sticky sand and clay loamy paddy soil, in the long-term retention, soil physical and mechanical properties of the magnitude of change