陕北黄土丘陵沟壑区14种植物的萌发特性

Seed Germination Characteristics of 14 species in the Hilly-gullied Loess Plateau of Northern Shannxi

在实验室条件下观测了陕北黄土丘陵沟壑区14种植物的萌发特性,结果发现：萌发率在80%以上的植物有杠柳、铁杆蒿和茭蒿;在60%-80%之间的物种有白羊草、紫丁香、阿尔泰狗娃花、大针茅、沙棘和猪毛蒿;长芒草为37.3%;小于20%的植物有达乌里胡枝子、刺槐、虎榛子和狼牙刺。14种植物的萌发时滞最短的为2 d,最长的为8 d;几乎所有植物种子达到T50的时间都在其萌发开始后的7 d以内,且大部分物种在萌发开始后的15 d完成总萌发量的90%;萌发持续时间最短的为6 d,有刺槐、狼牙刺、虎榛子、沙棘4种,最长的为猪毛蒿,达32 d。这些植物种子的萌发特性及生态适宜性决定了它们在陕北黄土丘陵沟壑区植被演替中的角色与地位。

A laboratory study was made on the germination characteristics of 14 species in the hilly-gullied region of Loess Plateau,North of shannxi,China.Results indicated that the germination rate of Periploca sepium,Artemisia gmelinii and Artemisia giraldii was over 80%,Bothriochloa ischaemum,Syringa oblata,Heteropappus altaicus,Stipa grandis,Hippophae rhamnoides and Artemisia scoparia was 60%80%,Stipa bungeana was 37.3%,while Cleistogenes caespitosa,Robinia psendoacacia,Sophora viciifolia,Ostryopsis davidiana was less than 20%.The shortest days of these species began to germinate was 2 d,the longest was 8 d,almost all the species with the day reaching 50% of the final germination amount was 7 d;most of the species reached 90% of the final germination amount within 15 days.The germination period of 4 species including R.psendoacacia,S.viciifolia,O.davidiana and H.rhamnoides was the shortest（6 d）,but the germination period of A.scoparia was 32 d.The role and status of these species in the vegetation succession was decided by their seed germination characterristics and ecological adaption in the hilly-gullied Loess Plateau of Northern Shannxi.