长期定位试验土壤钾素肥力变化及其对不同测钾方法的响应  

Change of Soil Potassium Fertility in Long-Term Located Field Experiment and Comparison of Different Methods to Measure Potassium Change in Soil

作　　者：孙海霞[1,2] 王火焰[1] 周健民[1] 杜昌文[1] 陈小琴[1] 钦绳武[1] 

机构地区：[1]土壤与农业可持续发展国家重点实验室中国科学院南京土壤研究所,南京210008 [2]中国科学院研究生院,北京100049

出　　处：《土壤》2009年第2期212-217,共6页Soils

基　　金：中科院创新工程重要方向项目(KSCX2-YW-N-002);国家自然科学基金项目(NSFC40201027)资助

摘　　要：土壤K素肥力因长期施肥管理可能会发生变化。本文以土壤K素肥力相对较高的河南封丘16年长期定位试验土壤为研究对象,分析比较了不同施肥处理对土壤K素肥力的影响,以及常规速效K、缓效K、全K和两种四苯硼钠法等土壤测K方法对土壤K素变化的响应能力。16年K肥施用量和作物吸K量的差值表明,不施K土壤K素发生耗竭,任何肥料都不施的CK处理K耗竭较少,为K 28.5 kg/(hm^2·a),而不施K的NP处理中K的耗竭速率较高,为CK处理的5.2倍,所有施K土壤中由于作物吸K量小于K肥施用量,表现为土壤K素盈余,其中不施P或N的NK和PK处理K素盈余最高,分别达K 207和190.5 kg/(hm^2·a),平衡施用化肥或有机肥土壤K的盈余较少,为K 31.5～63.0 kg/(hm^2·a)。不同土壤测K方法反映的16年前后土壤K素变化与以上理论值均有差异,醋酸铵法、沸硝酸法、两种四苯硼钠法和碱熔法反映的7个不同施肥处理K素变化的回收率(测定值与理论值的比率)平均值分别为39%、51%、66%、71%和176%,7个施肥处理回收率的变异系数5种方法分别为103%、74%、36%、30%和141%。回收率偏离估计值较大并且不稳定,说明土壤常规测K方法(速效K、缓效K和全K)不能够准确地反映土壤K素肥力的变化,而四苯硼钠法较常规方法可以较准确地反映土壤K素变化。Soil potassium fertility could probably be changed by long-term fertilization managcmcnt. Effect of 16-year different fertilization treatments on the change of potassium fertility in soil of a long-term field experiment located in Fengqiu County, Henan Province, China was studied in this paper. Five soil K testing methods （1 mol/L NH4OAC method, 1 mol/L boiling HNO3 method, total potassium method and two kinds of sodium tetraphenylboron （NaTPB） methods） were compared with regards to their ability to recover K change in soils. The results of soil K balance based on 16-year K input of fertilization and K removal by crop harvest showed that soil K depletion occurred in the soils without input of fertilizer K. K depletion rate of NP （apply nitrogen and phosphorus fertilizers） treatment was 5.2 time as that oftbe CK （without fertilizer） treatment which was K 28.5 kg,/（hm^2 ·a）. For all the other 5 treatments with fertilizer K applied, soil K got positive balance because that the amount of K applied was higher than the amount K removed by crops. The higher soil K accumulation rates were found in the NK （apply nitrogen and potassium fertilizers） and PK （apply phosphorus and potassium fertilizers） treatment, that was K 207 and 190.5 kg/（hm^2 ·a）, respectively. While the K accumulation rates in soils treated with balanced fertilizers were comparatively lower, which ranged from K 31.5 to 63.0 kg/（hm^2·a）. The change of soil K measured by 5 soil testing methods differred from the estimated value calculated by soil K balance and the mass of the topsoil in the field. The average recovery rate （ratio of value determined to the value estimated） of change of soil K of 7 fertilizers treatment determined by 5 methods （lmol/L N H4OAC method, 1 mol/L boiling HNO3 method, two kinds of NaTPB methods and total potassium method ） were 39%, 51%, 66%, 71% and 176%, respectively. The variation coefficient of the recovery rate of the above 5 methods were 103%, 74%, 36%, 30% and 141%, respective

关 键 词：潮土 长期定位试验 K测定方法 四苯硼钠 

分 类 号：S151.95[农业科学—土壤学]