摘要
为探讨稀土尾矿区人工培育苔藓的可行性及其关键影响因素,选择赣南典型的稀土尾矿,通过室内苔藓培育实验,研究土壤含水量和光照强度对稀土尾矿区苔藓生长发育的影响及其快速培育的可行性。结果表明:1)毛口藓(Trichostomum brachydontium)、卷叶毛口藓(Trichostomum involutum)、扭叶丛本藓(Anoectangium stracheyanum)、纤枝短月藓(Brachymenium exile)等苔藓植物种在稀土尾矿植被恢复过程中具有良好的适应性;2)土壤含水量和光照强度对稀土尾矿苔藓植物的覆盖度、植株密度及生物量的变化有显著影响。土壤水分含量是苔藓植物生长发育的最主要影响因素,接种后保持近地表土壤湿润是人工培育成功的关键;3)在稀土尾矿培育苔藓植物的最佳条件组合是地表土壤水分含量28%~30%+光照强度5900 lx,苔藓覆盖度在培育50 d后超过60%,在70 d达到100%;低水分(5%~8%)条件下,各光照强度苔藓植物均无法正常生长发育。综上,苔藓植物可作为稀土尾矿矿区生态修复的物种。
[Background]A large number of mine tailings have been generated by the excessive mining of rare earth ores.These tailings are characterized by low acidity,poor water storage capacity,low nutrient content,and high contents of rare earth and heavy metal elements,which seriously restrict the growth of plants.Biological soil crusts(BSCs)(associations of soil particles with mosses,fungi,algae,cyanobacteria,or lichens)are distributed extensively in South China,which can adapt to the arid and barren environment.Therefore,it may be used as an option for ecological restoration of mine tailings.However,limited information is available about the growth and influencing factors of artificial cultured BSCs in rare earth tailings.[Methods]Indoor incubation experiments of BSCs in the rare earth tailings were conducted to investigate the development characteristics of BSCs artificially cultivated in the rare earth tailings.Nine experimental treatments with 5 replications,including two factors(e.g.light intensity and soil water content)and three levels were randomly arranged.During the cultivation period(from November 2019 to July 2020),the coverage,plant density,and biomass of BSCs were dynamically monitored.The coverage,plant density,and biomass of cultivated BSCs were further statistically analyzed by univariate multivariate analysis of variance of a general linear model.[Results]1)The indoor incubation experiment showed that the coverage of BSCs reached 100%in 80 d,and the plant density was more than 54.8 plants/cm 2 in 140 d,under the condition of high moisture(28%-30%).No significant differences in plant coverage and density existed among different light intensities.2)Also under the condition of high moisture,significant differences in moss biomass were observed among different light intensities in a decreasing order as follows:86.79 mg/cm 2(at a medium light intensity of 5900 lx),70.15 mg/cm 2(at a high light intensity of 5900 lx),and 36.18 mg/cm 2(at a low light intensity of 1900 lx)(P<0.05).Under the conditions of medium soil moisture(13%-15%)plus medium light intensity,the coverage of BSCs was 54.07%,which was significantly higher than those under the conditions of medium soil moisture plus high light intensity and medium soil moisture plus low light intensity(P<0.05).Under the conditions of low soil moisture(5%-8%),BSCs could not grow and develop normally under all light intensities.[Conclusions]The obtained results indicate that BSCs could be used as a measure of ecological restoration in the rare earth tailings mining areas.Several moss species such as Trichostomum brachydontium,Trichostomum involutum,Anoectangium stracheyanum,and Brachymenium exile have good adaptability in vegetation restoration of rare earth tailings.Soil moisture is the most important factor affecting the development of BSCs.The optimal conditions for the growth of BSCs in rare earth tailings are soil water content of 28%-30%and light intensity of 5900 lx.
作者
沈发兴
郑太辉
段剑
胡瑞
喻荣岗
SHEN Faxing;ZHENG Taihui;DUAN Jian;HU Rui;YU Ronggang(Jiangxi Provincial Key Laboratory of Soil Erosion and Prevention,Jiangxi Academy of Water Science and Engineering,330029,Nanchang,China;College of Forestry,Jiangxi Agricultural University,330045,Nanchang,China)
出处
《中国水土保持科学》
CSCD
北大核心
2022年第4期136-144,共9页
Science of Soil and Water Conservation
基金
江西省土壤侵蚀与防治重点实验室开放研究基金“基于草本-苔藓复合体的土质工程创面生态恢复技术”(KFJJ202004)
江西省水利科技项目“生物结皮的水土保持效益及其人工快速培育技术”(201921YBKT05)
江西省博士后择优资助项目“生物结皮覆盖下红壤侵蚀劣地水沙异源及侵蚀响应”(2019KY49)
江西省水利科技项目“江西省典型堤防植草护坡生态控高技术研究与示范”(201922ZDKT10)。
关键词
稀土尾矿
苔藓植物
土壤含水量
光照强度
生物量
rare earth tailings
bryophytes
soil moisture content
illumination intensity
biomass
