黄土丘陵沟壑区山地苹果林土壤干化及养分变异特征  

Desiccation and Nutrient Status of the Soil in Apple Orchards in Hilly-Gully Region of the Loess Plateau

作　　者：李青华 张静[1,2] 王力 王延平[1,2] LI Qinghua;ZHANG Jing;WANG Li;WANG Yanping(College of Resources and Environment, Northwest A＆F University, Yangling, Shaanxi 712100, China;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences ＆ Ministry of Water Resources, Yangling, Shaanxi 712100, China)

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100

出　　处：《土壤学报》2018年第2期503-514,共12页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(41390463;41530854;41741002);城市与区域生态国家重点实验室开放基金项目(SKLURE2016-2-4)资助~~

摘　　要：揭示不同树龄苹果林土壤剖面水分特征及土壤养分演变规律,探明土壤干化引起的养分失衡原因,对黄土高原丘陵沟壑区苹果林地土壤水分、养分科学管理以及果园合理施肥具有重要现实意义。以陕北米脂县为研究区,选取不同树龄山地苹果林为研究对象,分别测定了7 a、10 a、18a、25 a、30 a和41 a苹果林地0~1 000 cm土层土壤湿度和0~300 cm土层土壤有机质、全氮、全磷、碱解氮、速效磷、速效钾含量,分析测定了深度范围内土壤干化情况、各养分指标丰缺状况及其随种植年限和土层深度的变异特征及不同树龄苹果林地60~300 cm土层土壤水分与养分的相互关系。结果表明:黄土丘陵沟壑区不同树龄山地苹果林深层土壤均出现严重或强烈干化,0~1 000 cm土层平均土壤含水量随树龄增加呈先增加后降低再略有增加趋势。该地区不同树龄苹果林0~300 cm土层土壤有机质、全氮和碱解氮含量均处于极缺状态,全磷、速效磷含量较缺,速效钾含量中等。幼龄期果树土壤水分与有机质、全氮、碱解氮相关性显著,而盛果期及衰退期果树土壤水分与各养分含量相关性不显著。建议不同树龄果园除应采取蓄水保墒措施外,尤其应注重有机肥和氮肥投入,适当增施磷肥,可少施或不施钾肥。相较于由干化引起的养分失衡,该地区土壤干化问题更应引起关注。【Objective】Mizhi County is a hill-gully region, typical of the Loess Plateau, where drought and shortage in water supply is a major factor restraining sustainable and healthy development of apple orchards. At the same time, soil fertility or nutrient status is another affecting tree growth and fruit yield and quality. Therefore, it is essential to study variations of water regime and nutrient status in the soil profiles of apple orchards different in cultivation history, and hence to explore mechanism of soil desiccation leading to nutrient imbalance, in an attempt to provide certain theoretic basis for scientific management of soil water and nutrients, soil building and rational fertilization in apple orchards in hillgully regions of the Loess Plateau.【Method】Distribution of soil water content in soil profiles, 1 000 cm in depth and nutrient contents, including soil organic matter, total nitrogen, total phosphorus, alkaline nitrogen, available phosphorus and readily available potassium, in the 0～300 cm soil layer of the profiles in the apple orchards, 7, 10, 18, 25, 30 and 41 years old, were determined; soil desiccation degrees and soil nutrient status along the soil profiles were evaluated for analysis of their relationships with cultivation history of the orchards and depth of the soil layer, and relationship between soil water content and soil nutrient contents in the 60～ 300 cm soil layers of the apple orchards relative to cultivation history. 【Result】Results show that the soils of the orchards, regardless of cultivation history, all suffered severe or intense desiccation. Mean soil water content of the 0～1 000 cm soil layer increased first, then decreased and then slightly turned upwards again with age of the orchards. The content of organic matter, total nitrogen and alkaline nitrogen in the 0～300 cm soil layers of the orchards, regardless of age, was less than 6 g kg^-1、0.5 g kg^-1 and 30 mg kg^-1, respectively, all falling down to the level of extreme deficiency, whilst the contents

关 键 词：山地苹果林 土壤干化 干化指数 土壤养分 养分短缺 

分 类 号：S158.2[农业科学—土壤学]