广东省柑桔园土壤养分肥力研究

掌握土壤养分肥力状况,是制定施肥策略的基础。本研究采集了广东省柑桔主产区果园土壤样本70个,分析了土壤有机质和N、P、K、Ca、Mg、S、Fe、Mn、B、Zn含量,评价土壤养分肥力现状并探讨其时空变化概况。结果显示:目前柑桔园土壤主要障碍因素是低镁缺硼及钾、钙、镁养分不平衡;与20世纪80年代末相比,土壤有效磷、锌、钾和氮含量有较大提高,有效钙含量降低,其余养分变化不大。土壤钙、镁含量在低水平上渐趋于相对平衡,而钾、镁不平衡状态仍然存在,甚至有所加剧;柑桔园土壤pH及多个中微量元素之间存在显著或极显著正相关关系。建议在柑桔果园增施镁、硼肥及石灰或其它碱性肥料,减施磷肥。

Soil Nutrient Fertility in Citrus Orchards of Guangdong Province

Knowing the soil nutrient fertility is the basis to formulate a suitable fertilization strategy.Seventy soil samples in citrus orchards in Guangdong province were colleted,and N,P,K,Ca,Mg,S,Fe,Mn,B and Zn level was analyzed.Soil nutrient fertility status and its temporal variation in the citrus orchards were researched.The main soil constrains in citrus orchards were low Mg,B deficiency and unbalanced among K,Ca and Mg.Compared with late(1980's),P,Zn,K and N level rose greatly,Ca content decreased,and the other nutrients still remained similar level at present.Ca and Mg tended to be balanced at low level,however,unbalance between K and Mg was still present and even more severe.Significant positive correlations were shown between soil pH and nutrients.It was suggested that more Mg,B,lime or other alkaline fertilizer and less P be used in citrus orchards.