纪家林场桉树LH1无性系人工林土壤养分研究

Study on Soil Nutrients of LH1,Eucalyputs urophylla×E.tereticornis Plantation in Jijia Forest Farm

为掌握雷州半岛桉树LH1无性系林的土壤养分概况,探索不同整地方式对土壤养分的影响,研究以全垦、开沟、挖穴3种整地方式造林,采用"5穴综合法"进行土壤取样,分析评价了LH1无性系林的土壤pH值、有机质、碱解N、速效P、有效K等11个养分指标,以及各指标与不同整地方式之间的关系。结果表明,LH1无性系碱解N较缺乏,土壤有机质,速效P、有效K处于中等水平,交换性Ca、Mg含量皆低于临界值,微量元素Zn 丰富,Cu、Mn适中,B较缺乏;不同整地方式对除土壤pH值外的其它10种养分指标的影响显著(P<0.05),开沟方式土壤中有机质、主要营养元素N、P、K,以及中量元素Ca、Mg的含量,都要高于挖穴和全垦的整地方式,桉树经营上可以利用开沟的方式营林,以增加土壤养分;整地方式对土壤中不同微量元素影响作用也很显著,并且在不同土层上表现不同。土壤养分指标之间既有促进作用,也有拮抗作用,与整地方式紧密相关;生产上可以针对微量元素B缺乏的现状,适量增加微量元素Mn或降低Mg来加以改善。

In order to master the soil nutrient condition of LH1,Eucalyputs urophylla×E.tereticornis clonal platation in Leizhou Peninsula and explore the impact of different land preparation methods on soil nutrient content,soil samples were collected by"five hole comprehensive method",and 11 nutrient indexes such as soil pH value,organic matter,alkali hydrolyzed N,available P and effective K,etc,were analyzed and evaluated,as well as the relations between the above indexes and the three preparation methods,namely,full cultivation,trenching and hole digging,that set up for afforestation in the study.The results showed that in soil the content of alkali hydrolyzed N is deficient,and the content of available P and effective K were in the middle level.The content of exchangeable Ca and Mg was lower than the critical value,the trace elements Zn was rich,Cu and Mn were moderate,and B was deficient.Different land preparation methods is significantly associated with all soil indexes except pH value(P<0.05).The content of organic matter,main nutrient elements N,P,K,and medium elements Ca and Mg in soil of preparation method trenching,are higher than the methods of digging holes and full cultivation.Eucalyptus management can use the way of trenching to increase soil nutrients.The effect of land preparation on different microelements in the soil is also significant,and the performance is different in different soil layers.Both promoting effect and antagonistic effect exist between soil nutrient indexes,that are closely related to land preparation methods.In production,increasing Mn or reducing Mg to improve the situation of lack of trace element B.