【摘要】 通过对四种植被类型的高山草甸土CO₂释放量的测定,可以看出:土壤呼吸作用强度因植被类型的不同而有区别,其中以金露梅灌丛土壤的呼吸作用为最高,杂类草草甸土壤的呼吸作用为低,呼吸作用有明显的昼夜变化,白天高于夜间,并以表层土为高,随土壤深度的加深而递减。四种植被的土壤呼吸作用与土壤微生物的数量和生化活性、土壤酶活性等均有不同程度的相关性;呼吸作用与土壤中的全氮、pH、代换量、有机质、速效钾和水解氮均有显著的相关性,与全钾和氮碳比相关性不显著。更多还原

【Abstract】 The soil samples were collected from Haibei alpine meadow ecosystem research station. The types of vegetation are Kobresia humilis meadow, Dasiphora fruticosashrub, Elymmus nutans meadow, and Forbs meadow. Depth of sampling soil were 0—10 cm, 10—20 cm, 20—40 cm, and 40—60 cm. Data of respiratory intensity showed in table 1.Experimental results showed that intensity of soil respiration varied with the types of vegetation and presented a noticeable diurnal and nocturnal fluctuation, the diurnal respiration was stronger than nocturnal one. Data also showed that the intensity of soil respirations varied with the depth of soil. The highest respiration intensity occurred in the surface layer and gradually diminished with the increased of the soil depth.Soil respiration in four types of vegetation was correlated with the number and activity of microorganisms, enzymic activities, and soil temperature respectively. Significant correlation could be found between the soil respirations and the total N, pH. cation-exchange capacity, organic matter, available K, hydrolyzable N respectively.更多还原