江西省油茶林地不同母岩土壤养分限制因子研究

摘要

The nutrient factors in main soils from oil tree forest land of Jiangxi Province were assessed by employing the systematic approach developed by Agro Services International and selecting sorghum as the indicating plant in order to evaluate the nutrient status and limiting factors. The results of soil testing showed that the four oil tree forest land soils were low in organic matter. Nitrogen ( N) , phosphorus (P) and potassium ( K) were severely deficient, but the available sulfur ( S) and iron ( Fe) were sufficient, the deficiency of calcium (Ca) , magnesium (Mg) , boron (B) , zinc (Zn) and molybdenum (Mo) were rather common. In the tested Camellia oleifera forest land soils, the larger capacity of adsorption and fixation belonged to sulfur (S) , copper(Cu) in quaternary red soil (JXD) and to phosphorus (P) , zinc (Zn) in Phyllite soil (JXQ) , while the capacity of adsorption and fixation of phosphorus ( P) , sulfur ( S) , boron ( B) , manganese ( Mn) in Sandstone soil (JXS) and copper (Cu), zinc (Zn) in granite soil (JXH) were weak. The results of pot experiment showed that the limiting factors and the nutrient deficient degree of granite soil were in the order of P > N > K > B (JXH); the limiting factors and the nutrient deficient degree of sandstone soil were in the order of N>P>K>Mn>Mo>Zn>Cu>B (JXS); the limiting factors and the nutrient deficient degree of phyllite soil were in the order of P > N > K > Mo > B > Cu > Zn (JXQ); the limiting factors and the nutrient deficient degree of quaternary red soil were in the order of P > N > K ( JXD). So phosphorus ( P) , nitrogen ( N) and potassium ( K) were the main nutrient limiting factors of oil tree forest land soils in Jiangxi Province, and then followed by zinc (Zn) , boron ( B) and molybdenum (Mo). The next field experiment should focus on the balanced fertilization of nitrogen (N), phosphorus (P), potassium (K), boron (B), zinc (Zn) , and molybdenum (Mo). Moreover, much attention should be paid to the supplement of calcium (Ca) and magnesium (Mg).%为评价江西省油茶林地不同母岩土壤养分状况及其主要限制因子,采用土壤养分系统研究法(ASI),以高粱为指示作物,对该省主要油茶林地土壤养分因子进行了测定与分析.土壤养分测定结果表明:供试油茶林地土壤中有机质的含量均较低,N、P、K元素严重缺乏,Ca、Mg、B、Zn、Mo等元素普遍缺乏,而S、Fe的含量丰富；供试土壤对养分的吸附能力显示:第四纪红壤对S、Cu和千枚岩类土壤对P、Zn的吸附固定量大,而砂岩类土壤对P、S、B、Mn和花岗岩类土壤对Cu、Zn的吸附固定量小.盆栽试验结果阐明:花岗岩类土壤养分限制因子及其亏缺程度的排序为P＞N＞K＞B；砂岩类土壤养分限制因子及其亏缺程度的排序为N＞P＞K＞Mn＞Mo＞Zn＞Cu＞B；千枚岩类土壤养分限制因子及其亏缺程度的排序为P＞N ＞K＞Mo＞B ＞Cu ＞Zn；第四纪红壤类土壤养分限制因子及其亏缺程度的排序为P＞N＞K.由此,P、N、K是江西省油茶林地土壤的主要养分限制因子,其次为Zn、B、Mo.文中还提出:下一步的田间试验应致力于N、P、K、B、Zn、Mo的平衡施肥,还应重视补充Ca与Mg元素.