【摘要】：干旱區(qū)典型草地土壤無(wú)機(jī)碳(soil inorganic carbon)的分布特征對(duì)于整個(gè)草地生態(tài)系統(tǒng)碳循環(huán)的研究具有重要的意義。本文基于新疆天山北坡8種典型草地剖面土壤無(wú)機(jī)碳含量的實(shí)測(cè)數(shù)據(jù),分析了天山北坡垂直帶草地類型與土壤類型的SIC分布特征及其影響因素,這對(duì)研究草地生態(tài)系統(tǒng)碳收支平衡和碳循環(huán)機(jī)制具有重要的意義。結(jié)果表明:(1)1m土層,高寒草甸、溫性山地草甸、溫性草甸草原、溫性草原、溫性荒漠草原、溫性草原化荒漠、溫性荒漠、低地鹽化草甸的SIC平均含量分別為:0.02、7.72、9.74、8.55、9.46、7.38、6.30、15.00 g·kg-1,其無(wú)機(jī)碳密度(SICD)分別為0.01、7.98、10.18、7.13、7.57、5.12、6.80、14.20 kg·m-2,平均SICD為7.37 kg·m-2,最大變異系數(shù)出現(xiàn)在0-20 cm土層。高寒草甸SIC含量及密度在土壤剖面上差異不明顯;溫性山地草甸SIC含量隨著土層深度的加深表現(xiàn)為先增后減的趨勢(shì),而其SICD則表現(xiàn)為逐漸增大的趨勢(shì),SIC主要儲(chǔ)存在50-100 cm,占0-100 cm土層的64.84%;其它6種草地SIC含量及密度隨著土層深度的加深表現(xiàn)為先增后減的趨勢(shì),主要分布在土層0-50 cm,所占0-100cm土層的50.04-75.87%。(2)不同土壤類型間的SIC分布差異明顯,高山草甸土與風(fēng)沙土SIC含量及密度隨著土層深度的加深無(wú)明顯變化。在0-70 cm土層灰棕漠土的SIC含量無(wú)明顯變化,但在底層70-100 cm SIC含量最低,而其SICD則表現(xiàn)為先增后減的趨勢(shì);鹽化草甸土的SIC含量與其SICD均隨著土層深度的加深表現(xiàn)為先增后減;隨著土層深度的加深黑鈣土、灰漠土、栗鈣土、鹽化草甸土、棕鈣土SIC含量表現(xiàn)為先增后減的趨勢(shì),而其SICD則表現(xiàn)為增加的趨勢(shì)。深度1m內(nèi),風(fēng)沙土、高山草甸土、黑鈣土、灰漠土、灰棕漠土、栗鈣土、鹽化草甸土、棕鈣土的平均SIC含量分別為:2.87、0.01、8.34、10.81、4.86、8.44、15.04、8.61 g·kg-1,SICD分別為:4.25、0.01、8.24、10.50、3.70、7.44、14.20、7.47kg m-2,平均SICD為7.18 kg·m-2。(3)pH與SIC含量在0-10 cm土層呈極顯著正相關(guān),在土層70-100 cm則達(dá)到極顯著負(fù)相關(guān);而與SICD在0-20 cm達(dá)到極顯著正相關(guān),20-50 cm呈顯著正相關(guān)。土壤容重與SIC含量在土層30-50cm達(dá)到顯著負(fù)相關(guān),土層50-100 cm達(dá)到極顯著負(fù)相關(guān);與SICD在表層0-5 cm呈顯著正相關(guān),而在土層70-100 cm則達(dá)到顯著負(fù)相關(guān)。在0-30、0-50 cm土層內(nèi)土壤SIC含量及SICD與年降水和海拔均呈負(fù)相關(guān)關(guān)系。(4)整個(gè)天山北坡0-30、0-50、0-100 cm土層SICD由西向東呈先增后減再增的趨勢(shì),均在精河低地鹽化草甸地區(qū)SICD達(dá)到最大,烏魯木齊南部與奇臺(tái)北部的高寒草甸SICD最低。
[Abstract]:The distribution characteristics of inorganic carbon (soil inorganic carbon) in typical grassland soils in arid area are of great significance for the study of carbon cycle in the whole grassland ecosystem. Based on the measured data of soil inorganic carbon content in eight typical grassland profiles on the northern slope of Tianshan Mountain, this paper analyzes the SIC distribution characteristics and influencing factors of grassland types and soil types in the vertical zone of the northern slope of Tianshan Mountain, which is of great significance to the study of carbon revenue and expenditure balance and carbon cycle mechanism in grassland ecosystem. The results showed that: (1) the average SIC contents of 1m soil layer, alpine meadow, warm mountain meadow, temperate meadow grassland, temperate desert steppe, temperate desert and lowland salinized meadow were 0.02, 7.72, 9.74, 8.5, 9.46, 7.38, 15.00 g kg-1, respectively. The inorganic carbon density (SICD) was 0.01, 7.98, 10.18, 7.13, 7.57, 6.80, 14.20 kg 路m -, respectively. The average SICD was 7.37 kg 路m-2, and the maximum coefficient of variation appeared in 0 脳 20 cm soil layer. There was no significant difference in SIC content and density in alpine meadow on soil profile, SIC content in warm mountain meadow increased at first and then decreased with the deepening of soil depth, while SICD increased gradually. SIC was mainly stored in 50 脳 100 cm, accounting for 64.84% of that in 0 脳 100 cm soil layer. The SIC content and density of the other six grasslands increased at first and then decreased with the deepening of soil depth, mainly distributed in the soil layer of 0 / 50 cm, accounting for 50.04 鈮，

本文編號(hào)：2506615