运用ET-100根系生态监测系统进行紫花苜蓿根系特征研究

Characteristics of Medicago sativa Root System by Using ET-100 Root System Ecological Monitoring System

运用引进设备ET-100根系生态监测系统,对两种紫花苜蓿(15°缓坡1年生、35°陡坡5年生)根系进行定时观测,分析不同条件下紫花苜蓿的根系生长状况。结果表明:缓坡当年生紫花苜蓿侧根发生的主要部位在距地面12—36 cm之间,0—12 cm之间仅有少量侧根发生,43 cm以下几乎没有侧根发生,根系生物量、主根直径整体上表现为从土壤表层到深层逐渐递减;当年生紫花苜蓿根系监测前期(9月15日—10月15日)在距地面18—33 cm之间生长最快,后期(10月16日—11月15日)在距地面43—53 cm之间生长最快,根系总长度增加量前期较后期大,但根系表面积、体积增加量则是后期比前期大;陡坡5年生紫花苜蓿根系发达、形状分散、分布均匀,在距地面30—70 cm之间生长相对较快,根系平均直径前期为4.3 cm,后期为5.4 cm。

The paper made regular observation on the root system of two kinds Medicago sativa(annual Medicago sativa growing on 15° gentle slopes and 5-year old Medicago sativa growing on 35° steep slopes)and analyzed the growth of the root system under the different conditions by using the imported equipment ET-100 root system ecological monitoring system.The outcomes show that a)the main part of lateral root of current growth Medicago sativa of gentle slopes emerges at 12-36 cm to the ground surface,only a few lateral root grows at 0-12 cm and there is almost no lateral root growing below 43 cm.The biomass of root system and the diameter of main root decrease gradually from the soil surface to deep layer,b) During the earlier monitoring stage(from September 15 to October 5) of current growth Medicago sativa root system,the part of 18-33 cm to the ground surface growing is the fastest.In the later stage(form October 16 to November 15),the part of43- 53 cm to the ground surface growing is the fastest.The earlier stage increase of total length of root system is greater than that of the later stage,while the increase of root surface area and volume of the later.stage is greater than that of the earlier stage,c) The root system of 5-year old Medicago sativa growing on steep slopes is developed,dispersed shape,even distribution and faster growing of 30-70 cm part to the ground surface.The average diameter of root system is 4.3 cm in the earlier stage and 5.4 cm in the later stage.