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Species diversity is the core content of the Biodiversity Research, is a very important element in the Community ecology and the whole ecological studies, it can not only reflect the communities or habitats of species richness, diversity, spatial and temporal changes in characterization of the community and characteristics of the ecosystem and its succession laws, and also reflects the relationship between the different natural and geographical conditions and human factors and community. In this paper, the Henan section of the Yellow River Basin study area, four habitats with different interference strength in different landscape types (mountains, hills, plains), select (flood land, farmland, abandoned land, plantation land) type to Compositae study, 1 month of May 2010 -2011 season four field investigations, surveys Asteraceae species distribution patterns, abundance of features, from the time and space to summarize Compositae species diversity distribution pattern and its environmental interpretation, understand the watershed scales plant community structure characteristics and distribution pattern, and to explore the impact of human disturbance convection within Asteraceae species distribution patterns, and their indirect impact on farmland ecosystem, which reveals maintain natural ecosystems and efficient agro-ecosystems, harmony, stability, health and sustainable development, the role of the mechanism, seeking to maintain a stable, healthy, efficient and sustainable watershed landscape of human interference with the environment of the ecosystem response between the balance point. After investigation, watershed Total Compositae 54 species belonging to 24 genera and common species: Conyza canadensis (Conyza canadensis), drill-type Aster (the Aster subulatus), cocklebur (Artemisia capillaries) Yinchenhao (Artemisia capillaries) and the like. Moderate basin-scale replacement by community types and the effects of natural and anthropogenic disturbances in different seasons, and in the same season of different habitats, the Asteraceae species diversity index and evenness index showed a certain degree of variation. Can be found through the study of the variation of species diversity in the different seasons: With the seasons (spring - summer - fall - winter), flood land and the farmland species diversity index showed a obvious turn downward trend; For plantation and abandoned land, species diversity indices in the spring, summer, fall, did not change significantly, which may be associated with the age of the plantation, canopy density and abandoned land abandonment ages; of species evenness Index trends in four seasons with a variety index consistent. The Compositae species distribution and diversity of the different types of landscape change. The mountain landscape types, hilly landscape types, plain landscape types in both Conyza canadensis punch Aster two large and widely distributed throughout the study area. Mountain landscape types the Altai Gouwa spend (Heteropappus altaicus), Artemisia annua (Artemisia annua), South Mu Artemisia (Artemisia eriopoda) more common; the hilly landscape type in Artemisia annua, Bailian Artemisia (Artemisia sacrorum) more; Compositae species in the the plains landscape type in more Bidenspilosa, Bidens pilosa, Cephalanoplos (Cirsium setosum), cocklebur. From midstream to downstream order mountain - hilly - plains, with the change of landscape types, species diversity index first increased and then decreased. Mountain landscape type, due to the impact of the topography, flood land is narrow, kind of investigation affected lower species diversity index; hilly landscape type type over mountain landscape types and plains landscape type, topography complex landforms, light and heat resources than rich types of mountainous landscapes, by the interference intensity is higher than the low plains landscape types, so the hilly landscape types in species diversity index; the plains landscape types, because of the population density, the intensification of human activities and the harm caused by biological invasions, the diversity index decreased dramatically. The species composition of structural differences in the four habitat types, with different intensities of disturbance in the same landscape type is also great. Floodplain habitat is subject to human interference the smaller habitat types, most of species diversity index and evenness index were higher; farmland habitat types is subject to human disturbance, are subject to strong interference plants throughout the growing cycle. diversity index and evenness index is the lowest; abandoned land and plantation habitats to their abandoned and planting time as well as the surrounding environment. This shows that in the case of disturbance does not reach the the species maximum tolerated degree, Asteraceae species tends to be distributed in the interference under ambient conditions, but when the interference reaches a certain extent, beyond the maximum tolerance levels of the species, Asteraceae The distribution of the plant will fall.
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