沙埋与水分对科尔沁沙地主要固沙植物出苗的影响  

Effects of water supply and sand burial on seed germination and seedling emergence of three sand-fixing Artemisia plants in Horqin Sandy Land

作　　者：温都日呼[1] 王铁娟[1] 张颖娟[1] 吴芳芳[1] 

机构地区：[1]内蒙古师范大学生命科学与技术学院,呼和浩特010022

出　　处：《生态学报》2015年第9期2985-2992,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金(31160130);内蒙古自治区自然科学基金(2011MS0524);内蒙古师范大学科学研究基金项目(RCPY-2-2012-K-049)

摘　　要：蒿属半灌木乌丹蒿(Artemisia wudanica)、白沙蒿(A.sphaerocephala)、差不嘎蒿(A.halodendron)是科尔沁沙地的主要固沙植物。其中乌丹蒿和差不嘎蒿是科尔沁沙地的本土植物,白沙蒿为来自于库布齐沙漠、毛乌素沙地的飞播植物。设置了5个沙埋深度(0.5、1.0、1.5、2.0和3.0 cm)和4个水分梯度(86、171、257和342 m L,分别模拟每月25、50、75和100 mm的降雨量),以探讨3种植物幼苗出土对沙埋和水分的响应。结果表明,沙埋与水分均显著影响着3种蒿属植物的幼苗出土(P<0.001)。3种植物最适沙埋深度在0.5—1.5 cm范围内,萌发出土时适宜水量要高于当地种子萌发期的平均降水量(50 mm/月)。两种固沙先锋植物乌丹蒿和白沙蒿的种子出苗率均显著高于差不嘎蒿,乌丹蒿较白沙蒿也明显为高,尤其在水分缺乏时,表现出两种先锋植物种子出苗对干旱有更好的适应性。协方差分析表明,乌丹蒿幼苗死亡率显著高于白沙蒿和差不嘎蒿(P<0.05),在达到75 mm/月降水量时,3种植物的出苗较好,但不能满足乌丹蒿幼苗生长对水分的需求,而实际种子萌发期的降水量平均只有50 mm/月。因而降水的缺乏导致乌丹蒿种群更新出现问题,加之飞播植物的竞争,使得近几年科尔沁沙地较多乌丹蒿种群出现衰退。Semi-shrubs,Artemisia wudanica,A. halodendron and A. sphaerocephala,are major sand-fixing plants in Horqin Sandy Land. A. wudanica is a native pioneer species growing in shifting,semi-shifting sandy land and A.halodendron is the dominant species in semi-shifting,semi-fixed and fixed sand dunes. A. sphaerocephala,sown by aerial seeding to Horqin,was imported from Qubqi Desert and Mu Us Sandy Land as a sand-fixing pioneer plant. Seed germination and seedling establishment are critical to the recruitment of individuals into plant communities,and therefore studies on seed germination and seedling emergence characters of the three sand-fixing plants are of great significance to vegetation restoration in Horqin Sandy Land. Seedling emergence is closely related to sand burial depth and soil moisture in sandy land. In this study,five sand burial depths（ 0. 5,1. 0,1. 5,2. 0 and 3. 0 cm） and four water supply levels（ 86,171,257 and 342 m L） were adopted to investigate the responses of three plants to sand burial and water supply during seedling emergence. Water treatments are equivalent to mean monthly precipitation of 25,50,75 and 100 mm,respectively,and the average monthly precipitation during grass germination period（ late May to early June） in the study area is about 50 mm. The results showed that,sand burial depth and water supply quantity had significant effects onseedling emergence in three plants（ P 〈0. 001）. The optimum depth for three species was 0. 5—1. 5 cm,suitable water supply at seed germination stage was higher than local monthly precipitation level（ 171 m L,i. e. 50 mm per month）,which resulted in a very low emergence rate. Within the scope of water supply in this study,the emergence and germination rates were the highest at 342 m L（ 100 mm per month） in most conditions,and the highest rates in three species was all appeared at 342 m L water supply and 1. 5 cm burial depth,showing that water supply contributed to seed emergence from slightly deep soil. Seedling emergence rates o

关 键 词：沙埋 水分 种子萌发 幼苗出土 蒿属 

分 类 号：Q945[生物学—植物学]