五个物种 40/25/20/10/5 → D = 0.7250，1/λ = 3.64 占比 0.40、0.25、0.20、0.10、0.05 得 λ = Σpᵢ² = 0.2750，Gini–Simpson D = 0.7250——随机抽两个个体有 72.5% 概率属于不同物种。倒数 1/λ ≈ 3.64，相当于约 3.6 个等丰度物种。{"result":"D = 0.7250 (Gini–Simpson) from S=5 species, N=100. Dominance λ = 0.2750, reciprocal 1/λ = 3.6364 (effective species), Simpson evenness = 0.7273. Weak dominance — abundance spread across taxa.","metadata":{"input":{"richness":5,"totalN":100},"result":{"richness":5,"totalN":100,"proportions":[0.4,0.25,0.2,0.1,0.05],"lambda":0.275,"giniSimpsonD":0.725,"reciprocal":3.6364,"evenness":0.7273,"interpretation":"Weak dominance — abundance spread across taxa","method":"λ = Σpᵢ²; D = 1−λ; 1/λ; E = (1/λ)/S"}}}
优势群落 90/5/5 → D = 0.1850，λ = 0.8150 一个优势类群占 90%、两个稀有种各 5%：λ = 0.8150、D = 0.1850——随机抽两个个体通常为同一物种。1/λ ≈ 1.23 个等效物种，尽管 S = 3 仍接近单优势种。{"result":"D = 0.1850 (Gini–Simpson) from S=3 species, N=100. Dominance λ = 0.8150, reciprocal 1/λ = 1.227 (effective species), Simpson evenness = 0.409. Strongly dominated — one taxon holds ≥ 80% of the probability mass.","metadata":{"input":{"richness":3,"totalN":100},"result":{"richness":3,"totalN":100,"proportions":[0.9,0.05,0.05],"lambda":0.815,"giniSimpsonD":0.185,"reciprocal":1.227,"evenness":0.409,"interpretation":"Strongly dominated — one taxon holds ≥ 80% of the probability mass","method":"λ = Σpᵢ²; D = 1−λ; 1/λ; E = (1/λ)/S"}}}