林下植被对寒温带兴安落叶松林土壤磷形态及有效性的影响  

Effects of Understory Vegetation on Soil Phosphorus Morphological and Availability in Larix gmelinii Forest in the Cold Temperate Zone

作　　者：朱正青 满秀玲[1] ZHU Zhengqing;MAN Xiuling(School of Forestry,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学林学院,哈尔滨150040

出　　处：《水土保持学报》2024年第2期339-350,363,共13页Journal of Soil and Water Conservation

基　　金：国家重点研发计划项目(2021YFD2200405)。

摘　　要：[目的]由于大兴安岭寒温带兴安落叶松林下植被差异较大,其土壤理化性质也有较大差异,研究不同林下植被兴安落叶松林土壤磷形态变化特征及有效性,为科学评价寒温带森林土壤磷素供给水平及磷循环研究提供科学数据。[方法]选取大兴安岭寒温带4种林下植被兴安落叶松林(兴安杜鹃-落叶松林、杜香-落叶松林、苔草-落叶松林和苔藓-落叶松林)为研究对象,于2022年6,8,10月采集0-5,5-10,10-20 cm土层土壤样品,采用Hedley磷分级法测定土壤不同形态磷含量。[结果](1)观测期间4种林下植被兴安落叶松林土壤活性磷(H 2 O-Pi、NaHCO_(3)-Pi、NaHCO_(3)-Po)和中等活性磷(NaOH-Pi、NaOH-Po)在6-10月总体呈降低趋势,中等活性磷含量占全磷的30.08%~52.80%,且中等活性磷均表现出无机磷含量高于有机磷含量。兴安杜鹃-落叶松林和杜香-落叶松林0-20 cm土层活性磷、中等活性磷含量均高于苔草-落叶松林和苔藓-落叶松林。苔草-落叶松林土壤稳定性磷(HCl-Pi、HCl-Po、residual-P)均显著高于其他3种落叶松林,且稳定性磷占全磷的58.86%~65.81%。(2)4种林下植被落叶松林土壤全磷(TP)、有效磷(AP)和磷活化系数(PAC)在6-10月变化范围分别为391.81~1081.02,7.34~83.90 mg/kg和1.62%~7.76%,兴安杜鹃-落叶松林和杜香-落叶松林土壤AP含量和PAC高于另外2种落叶松林,表现出较高的磷有效性;而苔草-落叶松林和苔藓-落叶松林在8,10月5-10,10-20 cm土层则出现供磷不足现象。(3)土壤含水率是兴安杜鹃-落叶松林和杜香-落叶松林土壤磷的主要影响因素,可溶性碳是苔草-落叶松林的主要影响因素,而铵态氮对苔藓-落叶松林影响较大。[结论]林下植被对兴安落叶松林土壤磷形态及磷有效性有显著影响,兴安杜鹃-落叶松林和杜香-落叶松林土壤活性磷组分、中等活性磷组分及有效磷含量较高,磷活化系数均在2.00%以上;而苔草-落叶松林土壤稳定[Objective]Due to the large differences in understorey vegetation and soil physicochemical properties of Larix gmelinii forest in the cold temperate zone of the Rreater Khingan Mountains,the characteristics and availability of soil phosphorus morphological changes of Larix gmelinii forest under different forests were studied,so as to provide scientific data for scientific evaluation of soil phosphorus supply level and phosphorus cycle in the cold temperate zone forest.[Methods]Four kinds of understory vegetation in the cold temperate zone of the Greater Khingan Mountains,namely,Larix gmelinii forest(Rhododendron simsii-Larix gmelinii forest,Rhododendron tomentosum-Larix gmelinii forest,Carex schmidtii-Larix gmelinii forest and Moss-Larix gmelinii forest)were selected as the research objects.Soil samples from the 0-5 cm,5-10 cm and 10-20 cm soil layer were collected from June,August and October 2022.Hedley phosphorus classification method was used to determine the phosphorus content of different forms in soil.[Results](1)During the observation period,soil active phosphorus(H_(2)O-Pi,NaHCO 3-Pi,NaHCO_(3)-Po)and medium active phosphorus(NaOH-Pi,NaOH-Po)of the four understorey vegetation Larix gmelinii forest showed a decrease trend from June to October,and the content of medium active phosphorus accounted for 30.08%to 52.80%of total phosphorus.The content of inorganic phosphorus was higher than that of organic phosphorus.The content of active phosphorus and medium active phosphorus in 0-20 cm soil layer of Rhododendron simsii-Larix gmelinii forest and Rhododendron tomentosum-Larix gmelinii forest were higher than those of the Carex schmidtii-Larix gmelinii forest and Moss-Larix gmelinii forest.The soil stability phosphorus(HCl-Pi,HCl-Po,and residual-P)in the Carex schmidtii-Larix gmelinii forest was significantly higher than that in the other three larix forests,and the stable state phosphorus accounted for 58.86%~65.81%of the total phosphorus.(2)Soil total phosphorus(TP),available phosphorus(AP)and phosphorus activ

关 键 词：大兴安岭 落叶松林 土壤磷形态 活性磷 有效磷 

分 类 号：S714[农业科学—林学]