摘要
通过对黄土高原地区旱作土壤与灌溉土壤综合考察、矿化培养实验与土壤、雨水分析,表明旱作土壤养分平均含量均低于灌溉土壤,其中有机质、全氮、碱解氦、有效磷的平均含量均属低水平,速效钾含量较高。旱作土壤可为作物利用的养分主要来源于土壤矿化、大气沉降和肥料投入。耕层土壤矿化氨量为每hm ̄277.1~116.9kg。每年每hm ̄2随降水进入土壤的氮量为4.52~10.60kg。1991年黄土高原旱作土壤施用化肥总量为47.50×10 ̄4t,平均每hm ̄2施入养分84.15kg,肥沃旱作土壤为153.30kg,均低于灌溉土壤。旱作土壤施用化肥比例为N:P_2O_5:K_2O=1.000:0.420:0.034。大力提高化肥投入量是旱作土壤农业增产的主要途径。
The field investigite,soil culture experment,soil analysis have been applied in this paper tostudies the nutrient content and nutrient supply of dry-farming soils。 The results from the studyshowed that soil nutrient average contents of the dry-farming soils has lower then of the irrigate soils。The nutrient source of dry-farming has comed from air nutrient down into soils,and soil nutrient min-eralization, and applied fertilizers。The nitrogen mineraliza of plough horizon has be 77.1~116. 9 kg。ha ̄(-1).The rainfall nitrogen down into soils has be 4.52~10. 60 kg· ha ̄(-1)·yr ̄(-1)·Applied fertilizershas be 53.55~153.30 kg· ha ̄(-1)·yr ̄(-1)·The fertilizer ratio N :P_2O_5:K_2O is 1.000:0.420:0.034。
出处
《西北大学学报(自然科学版)》
CAS
CSCD
1995年第2期117-122,140,共7页
Journal of Northwest University(Natural Science Edition)
关键词
旱作土壤
养分含量
养分供给
化肥投入
土壤
dry-farming soil
nutrient content
nutrient supply
applied fertilizer