乌兰布和沙漠天然白刺种群及主要伴生种种间关联性研究

采用2×2列联表，运用方差比率法（VR）、χ²统计量检验、联结系数（AC）和共同出现百分率（PC）等指标，以关联测度指标（OI、DJ、JI）为参考，对内蒙古自治区乌兰布和沙漠天然白刺（Nitraria tangtorum）种群及其伴生种的种间关联性进行分析，结果表明：天然白刺种群内8个主要物种总体关联性表现为无关联。在全部的28个种对中，15个种对表现为正联结，13个种对间表现为负联结。种对中除白刺–沙蒿表现为显著负联结外，其他种对间联结性均不显著。主要物种白刺与草本，草本与草本之间趋向独立分布。通过对天然白刺种群总体以及种间的关联性研究，为构建稳定的沙漠植物群落、恢复重建沙漠地区的植被、改善沙漠地区生态格局提供理论指导。

Interspecific Associations of Natural Nitraria tangtorum Population and Its Main Companion Species in Ulanbuh Desert

A series of techniques including the variance analysis (VR), χ²-test, the association co-efficient（AC）, the percentage of co-ocurrenc (PC) consulting the association indices（OI、DJ、JI）were used together with a 2×2 contingency table to analyze the interspecific associations of natural Nitraria tangtorum population and its main companion species in Ulanbuh Desert Inner Mongolia. Result: In the natural Nitraria tangtorum population，the association of 8 dominant species showed no correlation. By the calculation results, in the all 28 species-pairs, there are 15 species-pairs which revealed positive association, and 13 species-pairs revealed negative association. Most of the species-pairs revealed little significant association except Nitraria tangtorum–Artemisia ordosica. Nitraria tangtorum–Artemisia ordosica revealed significant negative association.. Nitraria tangtorum-herbage and other herbaceous species-pairs distributions trend to be independent. The result is very important to construct steady desert plant community, reconstruct desert plant community and regulate ecological pattern in theory.