Research On Leaf Nutrition Diagnosis Of Economic Forest In Southernloess Plateau

Mineral nutrition is the foundation to plant growth, yield formation and quality improving. To ensure the relative balance of plant nutrients was a important part of fertilization reasonable, but nutrition diagnosis is the scientific basis for fertilization reasonable. Therefore, this study established Diagnosis and Recommendation Integrated System and Deviation from Optimum Percentage through the study of actual investigation and sampling analysis. And this study provided a scientific basis of fertilization rational forest and high yield through diagnosised it. Main results are as follows:(1) This paper identified leaf nutrient appropriate value range and DRIS parameter of four main economic forest in the southern Loess Plateau, According to DRIS exponent classification norms, and obtained the appropriate DRIS index ranges of Zanthox ylum bumgeanum Maxim, Juglans regia, Diospyroskaki and Armeniaca vulgaris Lam leaf N, P, K, Ca, Mg, Mn, Fe, Cu, Zn and other elements.(2) The standard deviation, coefficient of variation, NII and∑DOP of leaf mineral nutrition elements have shown that the low-yield park was greater than the high-yield park. This indicated the nutrient value of the high forest is relatively stable, but low-yield forest there is a big difference in the nutrient elements.(3) Four main forest nutrient situation: the most Ca element lacking is in Zanthox ylum bumgeanum Maxim forest, followed by P, Zn, K, Mg, Mn, Fe and other elements, N elements could satisfy the basic needs of the tree's growth or excess; The most K element lacking is in Juglans regia forest, followed by Mn, Fe, N and other elements, Mg elements could satisfy the basic needs of the tree's growth or excess; The most Ca element lacking is in Diospyroskaki forest, followed by N, Mg, K, Zn and other elements, Fe elements could satisfy the basic needs of the tree's growth or excess; The most Ca element lacking is in Armeniaca vulgaris Lam forest, followed by Fe, Mn and other elements, P elements could satisfy the basic needs of the tree's growth or excess.(4) It should be focused on using the fertilizer containing P, Zn, Ca elements in ShanXi Hancheng region. It should be focused on using the fertilizer containing N, K, Fe, Zn elements in HuangLong region. It should be focused on using the fertilizer containing Ca elements in FuPing region.(5) DRIS and DOP diagnosis result were much the same, they apply to economic forest leaf nutrition diagnosis.