植被细根对典型黑土土壤抗蚀性的影响  

Effect of Vegetation Fine Root on Soil Anti-erodibility in Typical Black Soil Region of China

作　　者：李彦[1] 谷会岩[2] 陈月明 Li Yan;Gu Huiyan;Chen Yueming(Chinese Society of Forestry,Beijing 10091,P.R.China;Northeast Forestry University)

机构地区：[1]中国林学会,北京100091 [2]东北林业大学

出　　处：《东北林业大学学报》2020年第7期81-85,共5页Journal of Northeast Forestry University

基　　金：“十三五”国家重点研发计划项目(2018YFC0507003)。

摘　　要：在松嫩平原东北部、小兴安岭西麓的黑龙江省克山农场(东经125°7′40″~125°37′30″,北纬48°11′15″~48°24′7″)内,选择立地条件相近的樟子松(Pinus syvestris var.mongolica)人工林、水曲柳(Fraxinus mandshurica)人工林、水曲柳樟子松人工混交林(7水3樟)和以黄花蒿(Artemisia annua)、苔草(Carex tristachya)为优势种的天然草地为试验地,选择耕地作为对照试验地,在每个试验地内分别设置20 m×20 m的样地3块;在每块样地内沿1条对角线均匀机械布设3个样点,按照不同土壤深度(h)范围(0<h≤20 cm、20 cm<h≤40 cm)分层采集原状土用于抗蚀指数测定;在每块样地中沿2条对角线机械布设9个取样点,采集细根样品,测定细根的长度和根表面积;经植被细根的质量密度、根长密度、根表面积密度和土壤抗蚀指数的测定与计算,分析植被细根对黑土土壤抗蚀性的影响。结果表明:①研究的4种类型植被的细根组成中均以径级(d)0<d≤1 mm根系为主,乔木植被细根的质量密度、根长密度、根表面积密度均明显大于草地植被,下层土壤中差异更显著(P<0.05),显著提高了土壤的抗蚀性。②乔木植被主要是通过改变下层土壤(20 cm<h≤40 cm)中细根特征提高土壤的抗蚀性,而阔叶人工林、针阔混交林则主要是通过影响0<d≤1 mm径级细根特征提高其土壤的抗蚀性。建议:将植被0<d≤1 mm径级的细根特征作为科学评价黑土区植被保水固土能力的指标。The study was conducted in Keshan Farm of Heilongjiang Province(125°7′40″-125°37′30″E,48°11′15″-48°24′7″N).Pinus syvestris var.mongolica plantation,Fraxinus mandshurica plantation,mixed F.mandshurica and P.syvestris var.mongolica plantation(ratio of 7∶3)with similar site conditions and natural meadow dominated by Artemisia annua and Carex tristachya were selected as field experiment site.Three plots(20 m×20 m)were set up in each experiment site.Three soil samples were distributed in each plot following one diagonal according to uniform mechanical layout,soil samples,their natural structure preserved intact,were collected from 0<h≤20 cm and 20 cm<h≤40 cm,respectively,and tested for soil anti-erodibility index.Nine fine root samples were distributed in each plot following two diagonal,fine root sample were collected,and length and surface area were measured.Effect of fine root on black soil anti-erodibility were analyzed after measuring and calculating the weigh density,root length density,root surface density of fine root and soil anti-erodibility index.The results showed that:(1)In the four types of soil and water conservation vegetation,0-1 mm diameter root system is the main part of fine roots.The root weight density,root length density and root surface area density of the three arbor vegetation were higher than that of the grassland vegetation,and the difference was significant in the subsoil(P<0.05),and soil anti-erodibility promoted significantly;(2)Arbor vegetation can significantly enhance soil anti-erodibility through improving fine roots feature in subsurface soil(20 cm<h≤40 cm),and broadleaf plantation and mixed broadleaf-conifer can dramatically enhance soil anti-erodibility through improving fine roots feature in surface soil(0<d≤1 mm).Fine root features at 0<d≤1 mm diameter was proposed as evaluation index for calculated soil and water conservation capacity of vegetation in black soil region.

关 键 词：黑土 水土保持 植被 土壤侵蚀 根系特征 

分 类 号：S714.7[农业科学—林学]