摘要
本研究采用空间代替时间的方法,以天然草地作为对照,分析了内蒙古阴山北麓农牧交错带两种不同类型的草原(荒漠草原和典型草原)中的农田及3个不同恢复年限(5年、15年和20年)弃耕地的土壤理化性质,并采用主成分分析法对土壤质量进行综合评价。研究发现,弃耕后,土壤含水率、饱和导水率、毛管孔隙度、非毛管孔隙度、土壤有机碳、全磷、有效磷含量增加;土壤容重、硝态氮、铵态氮、全氮含量逐渐降低;土壤最大持水率指标在荒漠草原呈上升趋势,在典型草原下降;毛管持水率、田间持水率无显著变化(P>0.05);弃耕后,荒漠草原土壤pH降低,典型草原pH升高。基于统计分析的土壤质量得分表明,影响荒漠草原土壤质量的主要因素为土壤有机碳、非毛管孔隙度、容重、全氮,其土壤质量综合得分高低依次为天然草地>弃耕5年>弃耕20年>弃耕15年>农田,影响典型草原土壤质量的主要因子是pH、容重、饱和导水率、有机碳,其综合得分高低依次为天然草地>弃耕15年>弃耕20年>弃耕5年>农田。荒漠草原样地中,农田、弃耕地的土壤质量得分均低于平均水平,典型草原样地中弃耕15、弃耕20年、天然草地的土壤质量得分高于平均水平。由此可知,自发恢复有利于弃耕地的恢复。本研究结果表明,弃耕20年足以使典型草原弃耕地恢复至天然草地状态,但荒漠草原土壤尚未达到其最高土壤质量,需要使用更长的时间进行恢复,且针对荒漠草原与典型草原区需要制定不同的弃耕地土壤质量恢复策略。
This study used the method of substituting time with space,analyzing soil physicochemical properties between abandoned croplands(5,15 and 20 years)and farmland in the desert and typical grassland in the Northern Piedmont of Yinshan Mountain,Inner Mongolia.Natural grassland was used as a control.Soil quality was evaluated using principal component analysis.Results showed the following:with increased duration since abandonment,soil water content,saturated hydraulic conductivity,capillary porosity,non-capillary porosity,soil organic carbon,total phosphorus and available phosphorus increased;soil bulk density,the content of nitrate-nitrogen,ammonium-nitrogen and total nitrogen gradually decreased with increased duration since abandonment;maximum water holding capacity increased in desert grassland and decreased in typical grassland;capillary water holding capacity and field water holding capacity did not change significantly.As the duration of recovery increased,soil pH of desert grassland soils decreased but increased in typical grassland soils.Statistical analyses demonstrated that soil organic carbon,non-capillary porosity,bulk density,and total nitrogen were the main factors affecting desert grassland soil quality.Natural grassland had the highest soil quality,followed by abandoned croplands for 5 years,15 years,and 20 years,and farmland.Organic carbon,pH,bulk density,and saturated hydraulic conductivity were the main factors influencing soil quality in typical grasslands and the typical grassland comprehensive score was as follows:natural grassland>abandoned croplands for 15 years>abandoned croplands for 20 years>abandoned croplands for 5 years>farmland.In desert grassland samples,soil quality of farmland and abandoned land were lower than the average soil quality,while the soil quality scores of abandoned croplands for 15 years,and 20 years,and natural grassland,were higher than the average soil quality in the typical grassland samples.Therefore,passive restoration(without any intervention)is proposed as an effective strategy for grassland restoration in abandoned croplands.The results of our study indicate that 20 years is sufficient time to restore crops in typical steppes,but more time may be needed in desert steppes.For abandoned land,we must develop different strategies for restoring soil quality for desert grasslands and typical grasslands.
作者
乌云嘎
郑佳华
李邵宇
邢佳庆
赵天启
乔荠瑢
张峰
张彬
王占海
赵萌莉
Wuyunga;ZHENG Jiahua;LI Shaoyu;XING Jiaqing;ZHAO Tianqi;QIAO Jirong;ZHANG Feng;ZHANG Bin;WANG Zhanhai;ZHAO Mengli(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Hohhot 010019,Inner Mongolia,China;Key Laboratory of Grassland Resources,Ministry of Education,Inner Mongolia Agricultural University,Hohhot 010019,Inner Mongolia,China;Hulunbuir Agricultural and Animal Husbandry Technology Extension Centre,Hulunbuir 021008,Inner Mongolia,China)
出处
《草业科学》
CAS
CSCD
北大核心
2024年第3期548-560,共13页
Pratacultural Science
基金
内蒙古自然基金项目(2020ZD03)
现代牧区草地高效生产与家畜优化利用技术研发与示范(2021ZD0044)。
关键词
弃耕恢复
荒漠草原
典型草原
农田
土壤物理性质
土壤化学性质
土壤健康
abandoned land restoration
desert steppe
typical steppe
farmland
soil physical properties
soil chemical properties
soil healthy
