苏干湖盐沼湿地盐角草和海韭菜种群空间格局及其关联性

Spatial pattern and interspecific association of Salicornia europaea and Triglochin maritima populations in salt marsh of Sugan Lake

植物种群的空间格局及其关联性是其在群落中地位与生存能力的外在表现,反映了种群的生态调控能力及环境可塑性机制。在小苏干湖湿地,根据土壤含盐量大小选择轻度盐化区、中度盐化区和重度盐化区3个试验样地,应用点格局分析方法,研究了小尺度上盐角草(Salicornia europaea)和海韭菜(Triglochinmaritima)种群的分布格局及其空间关联性。结果表明:随土壤盐分增加,盐角草种群空间格局呈现出“随机分布—聚集、均匀分布—聚集分布”为主的转变;海韭菜种群由聚集分布为主转变为随机分布;二者空间关联性以负相关和不相关为主,种间关系由竞争转向无明确关系。苏干湖湿地土壤盐分的空间分布差异对植物种群的空间分布格局及其关联性影响显著,植物种群自身特性、种内种间关系以及环境条件等综合作用引起了湿地群落优势物种的更替。

The spatial pattern and association of plant population are the external manifestation of its position and survival ability in the community,which reflects ecological regulation ability and environmental plasticity mechanism of the population.In the Sugan Lake wetlands,three plots were selected with different soil salinity,including light salt zone,moderate salt zone,and heavy salt zone.The point pattern analysis method was used to study the distribution pattern and spatial association of Salicornia europaea and Triglochin maritima populations at small scale.The results showed that,with increasing soil salinity,the spatial pattern of S.europaea population exhibited a transformation of“random distribution-aggregation,uniform distribution-aggregation distribution”,while T.maritima population changed from aggregation distribution to random distribution.The spatial association between those two populations was mainly negatively correlated or non-correlated.Moreover,the interspecific relationship changed from competition to no definite relationship.The spatial distribution of soil salinity in Sugan Lake wetland significantly affected the spatial distribution pattern and interspecific association of plant populations.The replacement of dominant species in wetland community was influenced by plant population characteristics,interspecific relationships,and environmental conditions.