入侵藤本薇甘菊对酸性土壤的适应性  

The Adaptation of Mikania micrantha to Acid Soil

作　　者：胡亮[1,2] 邓太阳 张庆生 李鸣光[2] HU Liang;DENG Taiyang;ZHANG Qingsheng;LI Mingguang(Geography and Planning School, Sun Yat-Sen University, Guangzhou 510275, China;State Key Laboratory of Biocontrol, Sun Yat-Sen University, Guangzhou 510275, China;Greening Committee of Bao'an District, Shenzhen 518101, China; 4. Wildlife Management Department of Shenzhen, Shenzhen, 518048, China)

机构地区：[1]中山大学地理科学与规划学院,广东广州510275 [2]中山大学有害生物控制与资源利用国家重点实验室,广东广州510275 [3]深圳市宝安区绿化委员会,广东深圳518101 [4]深圳市野生动植物保护管理处,广东深圳518048

出　　处：《生态环境学报》2016年第9期1439-1445,共7页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(30370243);宝安生态防护林防治薇甘菊试验的效益监测项目

摘　　要：有害藤本植物薇甘菊(Mikania micrantha)原产中南美洲,现已对我国华南地区的植被和生态造成了严重危害。了解薇甘菊对非生物环境因子的适应性是对其进行科学治理的基本前提之一。华南地区以酸性土壤为主,而铝毒害是酸性土壤环境中植物生长的重要限制因子。为揭示薇甘菊对土壤pH条件及铝毒的适应性,本研究对比了薇甘菊在不同土壤pH环境下的萌发和生长情况;比较分析了薇甘菊3个不同种群和其他5种植物种子在不同浓度铝离子胁迫(0、0.5、1和2 mmol?L^(-1))下的种子萌发和幼苗生长;测定了深圳内伶仃岛薇甘菊及其他19种本地不同生活型植物茎干中3种微量元素(铝、锰和铁)的含量。结果表明,(1)薇甘菊种子在pH值为3.6~7.9的土壤环境中都能正常萌发,种子萌发率随土壤pH值的升高而逐渐降低;薇甘菊幼苗在pH值为4.3的条件下生长最佳,幼苗苗高、叶数、根数和根长都显著高于其他处理梯度。(2)当Al^(3+)浓度不高于2 mmol?L^(-1)时,薇甘菊种子的萌发率无显著组间差异,与对照植物相比也没有显著差异;但薇甘菊不同种群之间的差异明显,尤其是在幼苗存活率上。(3)薇甘菊茎干中铝(655.3 mg?kg^(-1))和铁(309.9 mg?kg^(-1))的含量均为20种受试植物中的最高值,分别是其余19种对照植物平均值的11.5倍和3.3倍;锰含量(469.4 mg?kg^(-1))仅次于鸭脚木,是其余19种植物平均值的2.7倍。以上结果表明薇甘菊对土壤酸碱度有较广的生态幅,对土壤铝离子毒害具有一定的耐受和富集能力,且铝离子毒害未影响薇甘菊对其他离子的吸收,因此对酸性土壤有较强的适应性。薇甘菊对酸性土壤的适应性有利于其成功入侵华南地区,而该区域土壤酸化的加剧可能进一步加重薇甘菊的潜在危害。Mikania micrantha is one of the world’s worst invasive plants. It is now widespread in the tropics and south subtropics ofChina. Here we try to reveal the adaptation of M. micrantha to acid soil and aluminum toxicity by a set of experiments. Seedgermination rate and seedling growth of M. micrantha in soil with different pH values were tested; seed germination rates andseedling mortalities of M. micrantha and other 5 weeds under different Al3+ stresses (0, 0.5, 1 and 2 mmol?L-1) were compared; andthe contents of three microelements (Al, Mn and Fe) in the stems of M. micrantha and other 19 species were compared. The resultsshowed that: (1) M. micrantha seeds could germinate in soil with pH values of 3.6~7.9 and its seedlings grew best in soil with pHvalue of 4.3. Its seed germination rate declined with increasing soil pH value. (2) The germination rate of M. micrantha seeds was notsignificantly different among groups when the concentration of Al3+ was not higher than 2 mmol?L-1. Seedling mortality indicatedthat Al-tolerance of M. micrantha was not significantly higher than the other tested species. However, the diffenence among M.micrantha populations is obvious, especially in seedling survival rate. (3) The content of Al in the stem of M. micrantha was thehighest (655.3 mg?kg-1), 11.5 times of the mean value of the other 19 tested plants. The content of Fe was also the highest (309.9mg?kg-1), 3.3 times of the mean value of the other 19 tested palnts. The content of Mn (469.4 mg?kg-1) was 2.7 times of the meanvalue of the other 19 tested plants. We concluded that M. micrantha has a wide ecological amplitude of soil pH. It is an Al-tolerantplant. The adaptability of M. micrantha to acidic soil was favorable to its successful invasion in southern China. The exacerbated soilacidification in southern China may increase the risk of this species.

关 键 词：薇甘菊 铝毒 土壤PH 种子萌发 幼苗生长 微量元素 

分 类 号：Q948.113[生物学—植物学]