紫胶林-农田复合生态系统的蚱总科昆虫多样性

Diversity of Tetrigoidea Insects in Lac-Plantation-Farmland Ecosystem

在云南绿春县采用网扫法调查紫胶林-农田复合生态系统稻田、旱地、天然紫胶林和人工紫胶林4个不同土地利用生境的蚱总科昆虫群落。共采集蚱606头,隶属于6科33种;其中蚱科、刺翼蚱科和短翼蚱科物种丰富。运用ACE方法对物种丰富度估计的结果表明:调查中实际采集到的蚱类物种接近物种丰富度估计值的90%。紫胶林-农田复合生态系统蚱类物种多度分布符合对数正态分布,分布模型为S(R)=8exp-(0.2R)2[χ2=0.688<χ2(4,0.05)=8.488;R2=0.623],显示出该生境利于蚱类的生存。不同土地利用生境蚱类物种多样性不同:稻田蚱类物种丰富度和多样性最高,旱地和人工紫胶林次之,天然紫胶林多样性最低。一些蚱对于不同土地利用生境具有明显的选择性,有7种蚱(IndVal≥0.5,P<0.05)能作为该系统内不同土地利用生境的指示物种:贡山柯蚱、宽顶瘤蚱、云南瘤蚱和圆肩悠背蚱是稻田的指示物种,短背扁角蚱和长跗波蚱是天然紫胶林的指示物种,而上思庭蚱是人工紫胶林的指示物种。在紫胶林-农田复合生态系统中,蚱比蝗虫能够更好地反映土地管理对昆虫多样性的影响。运用IndVal指数进行指示物种筛选比单独依靠物种个体数更科学。

Tetrigoidea insect assemblages were investigated by sweep netting in paddy field,dry land,natural forest,and plantation forest in lac-plantation-farmland ecosystem in Lüchun County,Yunnan Province.A total of 606 specimens were collected,representing 33 species in 64 families of Tetrigoidea,among which insects of Tetrigidae,Scelimenidae and Metrodoridae were more abundant.According to the estimators of Chao1,the captured species were nearly 90% of the estimate value of species richness.The species abundance distribution in the agroforestry ecosystem fitted Log-normal model well,and the model was S（R）=8exp-（0.2R）2（χ2=0.688χ2（4,0.05）= 8.488;R2=0.623）,indicating fine environment for the Tetrigoidea insects.The species diversity of Tetrigoidea insects differed across the four habitats.The Tetrigoidea species richness and diversity in paddy field were highest;those in dry land and in plantation forest were moderate,while those in natural forest were lowest.Some Tetrigoidea insects preferred some habitats to the others,and there were seven indicator species（IndVal≥0.5,P0.05） in the different land-use habitats in the agroforestry ecosystem.Coptotettix gongshanensis,Thoradonta lativertex,T.yunnana and Euparatettix circinihumerus were indicators for paddy filed,Flatocerus brachynotus and Bolivaritettix longitarsus were indicators for natural forest,and Hedotettix shangsiensis was indicator for plantation forest.In lac-plantation-farmland ecosystem,Tetrigoidea insects reflected the effect of land management on insect biodiversity better than that of grasshoppers.It is more reasonable to identify bioindicator by IndVal index than only by individual numbers.