秆粪肥在赤红壤中的矿化研究

STUDY ON HUMIFICATION AND MINERALIZATION OF DIFFERENT KINDS OF STALK-DUNG FERTILIZERS IN LATORED SOIL

采用十一种有机物肥进行矿化研究，肥效试验设高、中、低化肥水平比较．结果表明：（１）不同肥料对玉米苗期干物重的影响是：粪肥＞化肥＞秆肥．施入６２ｄ，土场总碳量是，施粪肥的比对照高１．３７倍，施秆肥的高１．２４倍，单施化肥的反比对照下降１４．３％。当然，不同秆粪肥的肥效也不完全一样．（２）在南方高温多雨的条件下，秆粪肥施入土壤后的分解是很快的，尤其是施后的第一个月，其分解速率杠肥平均为４３．４％；粪肥为３５．４％．秆肥中分解最快的是玉米秆，最慢的是甘蔗渣，分解速率分别为５０．１％和２３．４％；粪肥中分解最快的是鸡粪，最慢的是鸭粪，分解速率分别为５５．７％和２１．５％．一个月后分解速率则明显下降．秆粪肥在土壤中的分解一直延缓到三年以后。（３）施后第一年的腐殖化系数，秆肥为２．５４３×１０（－３）－４．３１９×１０（－３），其中番薯藤的最大，黄豆秆的最小；粪肥的除鸡粪和猪粪较小外，牛、鸭粪的达４×１０（－３）以上。一年以后便逐年明显减小．

Eleven kinds of organic fertilizers were studied. The effects of the fertilizers were compared among high, medium and low application rates. The results were as follows:i)The effect of different kinds of fertilizers on the dry weight of maize seedlings was the highest for dung followed by inorganic fertilizer and then by stalk. On the sixty-second day of the growing period,the total carbon content in the dung fertilized soil was 2.37 times and in stalk fertilized soil was 2. 24 times as much as that in non-fertilized soil,while in inorganic fertilized soil the total carbon content decreased by 14. 3%. The fertilizer efficiency were also different among the different kinds of stalk-dung fertilizers.ii)Under rainy and high temperatuer conditions in southern China the decomposition rate of the stalk-dung fertilizer was high after fertilization,especially in the first mouth. The decomposition rates were 43. 4% for stalk and 35. 4% for dung on the averages. Among the different kinds of stalk,the decomposition rates were the highest for maize stalk and the lowest for bagasse and the rates of them were 50. 1% and 23. 4%,respectively. Among the different kinds of dung, the decomposition rates were the highest for chicken dung and the lowest for duck dung and the rates of them were 55. 7%and 21. 5%, respectively. After one month's application the decomposition rate of any kinds of organic fertilizers decreased markedly. The decomposition of the fertilizers lasted for more than three years.iii)In the first year, the humification coefficient varied from 2. 543×10(-3) to 4. 139 ×10(-3) among different kinds of stalk after fertilization. The highest was for sweet potato vines and the lowest was for soybean stalks. The coefficient varied from 1. 979×10(-3)to 4. 246×10(-3) among different kinds of dung. The humification coefficient was relatively lower in chicken dung and pig dung but in cow dung it was higher than 4×10(-3).The coefficient decreased apparently after fertilization for one year. The decreased rates differed among the different kinds of the fertilizers.