Response of Herbaceous Vegetation Communities in Terraces of Ecological Isolation Zones in the Mountain Red Soil Area

Abstract

Through a sample survey of the research area of the Yunnan Agricultural University (YAU) Research Base in Malong Jiuxian County, we summarized the types of herbaceous vegetation communities in the terraces of the ecological isolation zone of the area, analyzed the species’ importance value, Patrick index, Simpson index, Shannon-wiener index, and Pielou index, and then explored the different patterns (annual and two-years artificial sowing patterns and natural secondary community patterns) under three different slope positions at the top, middle and bottom of the slope. The results indicated that: 1) there were 34 species of vascular plants, 15 families, and 32 genera in the study area, including one family, one genus, and one species of Ferns, and 14 families, 31 genera, and 33 species of Dicotyledons, mainly in the Asteraceae Bercht. & J. Presl, Poaceae Barnhart, and Fabaceae Lindl. Among them, 26 species and 11 families of vegetation were at the top of the slope, mainly Asteraceae Bercht. & J. Presl; 23 species and 13 families in the middle, with the most significant proportion of Asteraceae Bercht. & J. Presl; 30 species and 13 families at the bottom, mainly Asteraceae Bercht. & J. Presl, Poaceae Barnhart, Fabaceae Lindl., and Rosaceae Juss. 2) the species importance value of Asteraceae Bercht. & J. Presl was the largest in the study area; Artemisia, Imperata cylindrica (L.) Beauv., Miscanthus Sinensis Anderss., Bidens Pilosa L., Erigeron acris L., and Galium odoratum (L.) Scop. were the dominant species. 3) low diversity, good stability, and high evenness index of herbaceous vegetation communities planted artificially in one year; the herbaceous community with better species diversity and lower stability and decreased evenness index in the two-year artificial planting than in the one-year artificial planting; one-year natural secondary herbaceous communities with low diversity index and poor richness index; two-year natural secondary herbaceous communities had better diversity and high species richness index, but decreasing evenness. In the configuration of the ecological isolation zone community of the mountain red soil should be paid to select faster-growing species that are not easily replaced by playing the role of ecological isolation.