民勤绿洲边缘2种生境红砂种群分形特征及影响因素  

A study of fractal properties of spatial distribution of Reaumuria soongorica population and its influencing factors in Minqin Oasis Fringe

作　　者：付贵全 徐先英[1,2] 徐梦莎[3] 孟源源[4] 赵鹏[2] 刘江[1] 

机构地区：[1]中国林业科学研究院,民勤治沙综合试验站,民勤733000 [2]甘肃省治沙研究所,荒漠化与风沙灾害防治国家重点实验室培育基地,兰州730070 [3]中国林业科学研究院,国家林业局泡桐研究开发中心,郑州450003 [4]浙江农林大学,环境与资源学院,临安311300

出　　处：《生态学报》2016年第18期5768-5776,共9页Acta Ecologica Sinica

基　　金：国家重点基础研究发展计划(2012CB723203);国家自然科学基金资助项目(41161006);国家科技支撑项目(2012BAD16B0203);甘肃省青年基金(1308RJYA081);甘肃省沙生植物保护利用科技创新团队资助项目(1207TTCA002)

摘　　要：以民勤绿洲边缘丘间低地和梭梭林固定沙丘2种生境下红砂种群为研究对象,采取空间替代时间和分形维数(计盒维数、信息维数和关联维数)研究了红砂种群的结构特征和空间格局的分形特征,并对其影响因素做了主成分分析,研究结果表明:(1)红砂种群在丘间低地生境下,主要集中在龄级Ⅰ,更新较好;在固定沙丘生境下,主要集中在龄级Ⅲ,更新受到很大的限制。(2)与梭梭林固定沙丘生境下相比,丘间低地生境下红砂种群个体间竞争较弱,但占据和利用空间能力较强且格局强度较大。红砂种群的计盒维数和信息维数对种群的个体数量、更新状况和分布情况反映灵敏,而且关联维数在干旱地区有其特定的生态学意义,即只表示种群竞争的强弱。(3)分形维数不仅与群落结构(密度、幼体数量等)有关,还与生境因子有关。主成分分析表明,土壤结皮类型是红砂种群格局分形维数的第一主成分,土壤含水量、土壤全盐量分别是第二和第三主成分,这三个主成分的累计贡献率为80.002%。(4)建议在防风固沙和植被恢复时,丘间低地生境下可以通过增大红砂Ⅰ小龄级个体的密度来提高整体的防风固沙能力和幼苗的成活量,但在梭梭林固定沙丘生境下如何提高红砂Ⅰ小龄级个体的成活率是保护和利用红砂的关键。Selecting the two ecological habitats （interdunal depression and fixed dunes） of the Minqin oasis fringe as our study area, the chronosequence method, fractal dimension （including box-counting dimension, information dimension and correlation dimension） analyses, and principal component analysis were used to study the population structure and spatial heterogeneity of Reaumuria soongorica, as well as the primary factor influencing these characteristics. The results were as follows：（1） R. soongorica individuals in the interdunal depression, which were mainly in age class Ⅰ, regenerated more readily than those of age class Ⅲ growing on the fixed dunes. （2） The intraspecific competition within R. soongorica was not intense in the interdunal depression, but the population occupied and utilized relatively larger ecological spaces here and exhibited higher levels of spatial heterogeneity when compared to those in the fixed dunes habitat. In addition, the box-counting dimension and information dimension methods were sensitive to individual number, renewal ability, and spatial pattern, while the correlation dimension was often used to illustrate the potential for intraspecific competition in arid regions. （3） Besides community structure （which includes the population density and seedling abundance）, environmental factors affected the fractal dimensions. The principal component analysis suggested that soil crust type was the primary principal affecting the fractal dimension, followed by soil water content and soil salt content, which together accounted for 80.002% of the variance within the fractal dimension. （4） When these ecological projects （such as windbreak, sand-fixation, and vegetation rehabilitation） were conducted, it was advised that the windbreak, sand-fixation, and survival rate of seedlings were improved by increasing the individual density of R. soongorica plants in age class Ⅰ growing in the interdunal depression. Thus, strategies for facilitating increase in the surviv

关 键 词：红砂种群 生境 格局 分形特征 民勤绿洲边缘 影响因素 

分 类 号：Q948.1[生物学—植物学]