外源竹炭对土壤硝酸根离子的吸附效应  

Bamboo char adsorption efficiency on soil nitrate anions

作　　者：沈泉 沈颖[1,2] 徐秋芳[2] 王炀波 

机构地区：[1]浙江省长兴县林业局,浙江长兴313100 [2]浙江农林大学环境与资源学院,浙江临安311300

出　　处：《浙江农林大学学报》2014年第4期541-546,共6页Journal of Zhejiang A&F University

基　　金：国家科技重大水专项子课题专题(2008ZX07101-006-06)

摘　　要：生物质炭巨大的活性表面,可吸附土壤中的硝酸根等阴离子养分.采用竹炭作为试验材料,以自然土壤和人为耕作土壤为试验土壤,用硝酸钾溶液浇施模拟施肥,通过离子色谱测定浇施后所得滤液中硝酸根离子的含量,分析竹炭对土壤中硝酸根离子的吸附效果.试验设计如下：自然土壤加入的竹炭百分比为0,1％,2％,3％,4％（竹炭直径＜1 mm）,耕作土壤加入的竹炭百分比为0,1％,3％,5％（竹炭直径为1～2 mm）,2种竹炭颗粒（1～2 mm和＜1 mm）比较试验时加入的竹炭量为3％.结果表明：土壤中加入竹炭对硝酸根离子的吸附有一定的作用,前2次淋洗表现为吸附作用随着竹炭比例的增加而增强,但只有加入的竹炭量超过3％后,吸附效果没有显著提高（P＞0.05）.在加入等量（3％）竹炭时,前2次淋洗时颗粒直径为1～2 mm的竹炭吸附效果好于＜1 mm的竹炭,细粒与对照没有差异,第3次淋洗时竹炭处理与对照差异显著（P＜0.05）,但不同颗粒之间差异消失.竹炭的施入比例和颗粒直径均能影响其对土壤中阴离子的吸附效果.建议生产上采用3％比例、颗粒直径为1～2 mm的竹炭,以减少硝酸根离子的淋失.Biochar with a huge active surface area can absorb anions, such as nitrate, in soils. To test adsorp tion efficiency of bamboo char on nitrate anions of soils, two types of soils （natural and cultivated） and two sizes of bamboo char particles [ 1-2 mm with bamboo char percentages of 0（control,ck）, 1%, 3%, and 5% and 〈 i mm with percentages of 0 （ok）, 1%, 2%, 3%, and 4% ] were used. For comparison of the two particle sizes, the 3% bamboo char treatment was utilized. A potassium nitrate solution （KNO3） was mixed in the soil and then leached with ion-free water. After, the NO3- concentration was determined with ion chromatography. Resuits showed no significant increase in absorption capacity efficiency （P 〉0.05） for soils with more than 3% bamboo char. For the first two leachings, when soils treated with equivalent amounts of bamboo charcoal （3%） were compared to ck, the soil with the 1-2 mm size bamboo char had a significantly higher （P 〈 0.05） absorption capacity for nitrate anions than the 〈 1 mm and ck. During the third leaching, significant differences （P 〈 0.05） were observed between ck and soils with bamboo char （both 〈1 mm and 1-2 mm size）. Thus, absorption efficiency of anions was related to both proportion and particle diameter of bamboo charcoal with 3% bamboo char at 1-2 mm diameter being the most economical rate to reduce soil nitrate leaching.

关 键 词：土壤学 竹炭 吸附作用 硝酸根离子 颗粒直径 比例 

分 类 号：S156.2[农业科学—土壤学]