Abstract:

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=0.688<χ²(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,P<0.05) 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.

Key words: agroforestry ecosystem, indicator species, IndVal index, Tetrigoidae, species abundance, agricultural land uses, Kerria spp.