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中国沙漠 ›› 2007, Vol. 27 ›› Issue (6): 1000-1006.

• 生物土壤与生态 • 上一篇    下一篇

科尔沁沙地人工林下结皮发育对表土特性影响的研究

郭轶瑞; 赵哈林; 赵学勇; 左小安; 罗亚勇   

  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2007-11-20 发布日期:2007-11-20

Crust Development and Its Influences on Soil Physicochemical Properties in Artificial Forest of Horqin Sand Land

GUO Yi-rui; ZHAO Ha-lin; ZHAO Xue-yong; ZUO Xiao-an; LUO Ya-yong   

  • Received:1900-01-01 Revised:1900-01-01 Online:2007-11-20 Published:2007-11-20

摘要: 通过野外取样和室内分析相结合,对科尔沁沙地不同生长年限人工林下土壤结皮的理化性质及结皮发育对表层土壤特性的影响进行了初步研究。结果表明,3 a、15 a生杨树林下分别发育了物理结皮、地衣结皮和苔藓结皮,15 a、25 a生樟子松林下均发育了苔藓结皮,结皮的厚度、紧实度、水分、粘粉粒含量及全效、速效养分等随物理结皮向苔藓结皮的发育依次增加。同时,结皮的存在增加了其下层土壤颗粒组成中的极细沙和粘粉粒含量,富集了结皮下土壤的有机质、全N、全P、速效N、速效P等养分,而且结皮对下层土壤的这些影响作用从物理结皮、地衣结皮到苔藓结皮呈逐渐增长的趋势。同一结皮下土壤粘粉粒含量、养分含量在0—5 cm范围内由表及里呈递减趋势,但均高于对照无结皮层相对应的值。25 a生樟子松林下发育的苔藓结皮及其下层土壤的理化状况明显优于其他人工林下结皮的情况。

关键词: 科尔沁沙地, 杨树林, 樟子松林, 结皮发育, 土壤理化性质

Abstract: Soil crust is a common and widespread phenomenon in desert areas all over the world thanks to its extraordinary ability to survive desiccation and extreme temperatures,high pH and salinity. Despite its unassuming appearance,biological soil crusts play a significant role in desert ecosystems,including involvement in the process of formation,stability and fertility of soil,preventing soil erosion by water or wind,increasing the possibility of vascular plant colonization,and being responsible for the stabilization of sand dunes. The present paper taking Horqin Sand as the research region,by field sampling,the soil crust sample under different ages of artificial forest were collected,and its physical and chemical properties were analyzed,in which the mechanical composition,bulk density,soil nutrient elements,organic matter,pH,EC and CaCO3 content of the crust and soil(0\_2.5 cm and 2.5\_5 cm under crust)were included.The result revealed that 3-year-old and 15-year-old Populus simonii forest,15-year-old and 25-year-old Pinus sylvestris var. mongolica plantation were respectively developed soil crust,lichen crust and moss crust. The thickness,packing degree,water content,silt and clay content,total and available nutrients of crusts are gradually increasing along with the crust development succession. Meanwhile,crust enhanced the physical characters and chemical properties of the soil under it,on an increase trend from Populus simonii forest to mongolica plantation,from soil crust to moss crust. Of the same forest,the above parameters in 0-2.5cm soil layer were higher than that of 2.5-5cm soil layer and the contrast. The result also showed that the physical characters and chemical properties of moss crust which under 25-year-old mongolica plantation were prior to others,and so does the 0-5cm soil layer under it.

Key words: Horqin Sand Land, Populus simonii forest, Pinus sylvestris var. mongolica plantation, crust development, physical and chemical properties