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在广州的赤红壤上进行六种农作制的五年试验表明,所有衣作制的氮平衡均盈余,其中水稻连作的农作制氮盈余较少,而含豆科作物者尤其是牧草大绿豆混播及双季稻冬种绿肥盈余最多,后者年亩增加氮素约10kg;各农作制氮盈余的原因是具有较高的氮肥效率和土壤全氮量显著增加。磷平衡在所有农作制中皆为亏损;磷肥效率低,多数衣作制投入的磷约有1/3移至耕层以下。钾平衡在含水稻的衣作制中亏损艮大,旱作者接近平衡或盈余;钾亏损的原因是含水稻的农作制钾的淋失量大,平均达投入的44％:土壤经种植五年后钾含量一般只能维持原有水平。养分平衡状况表明,供试六种衣作制中,油一茨和牧草混豆科作物两个农作制最有利于养分平衡,亏损较少,其次是油—稻和稻—肥两个农作制亦较有利于养分平衡。试验还说明稻秆和豆科作物基秆回田是维持农作制中氮平衡、钾平衡的重要手段。
A five-year trial of six cropping systems on latosolic red soil in Guangzhou showed that all crop yields had a surplus of nitrogen balances, of which crop continuous cropping with rice had less nitrogen surplus and those with leguminous crops, especially pasture grass Mung bean mixed sowing and double cropping rice winter most of the green manure surplus, the latter increase about 10kg of nitrogen per kilogram; each crop nitrogen surplus is due to higher nitrogen efficiency and soil total nitrogen increased significantly. Phosphorus balance is a loss in all cropping systems; the efficiency of phosphate fertilizers is low, and about one-third of the phosphorus input from most garment systems goes below plow. Potassium balance in the rice-containing rice system deficit burgundy, dry close to balance or surplus; potassium loss is due to rice-containing rice crop leaching loss of large, an average of 44% of the input: the soil after planting five After years of potassium content generally only maintain the original level. Nutrient balance shows that the two cropping system for the test six kinds of oil, fertilizers and fodder mixed leguminous crops two farming system most conducive to nutrient balance, less loss, followed by the oil - rice and rice - fertilizer two farmers The system is also more conducive to nutrient balance. The experiment also showed that rice straw and leguminous crops straw back to the field is an important means to maintain nitrogen balance and potassium balance in farming system.