Abstract:

Investigations were conducted of species composition and abundance of vegetation in suburban agricultural region, Qianjiang, Hubei Province in 1996 and 2013, for the purpose of revealing trend of the temporalspatial variation of distribution of plant diversity in agricultural landscapes on the background of the development of intensive agriculture and urbanization. Results show that the plant diversity in the studied area as a whole displayed a declining trend from 1996 to 2013; in the cropland habitat, species richness dropped quite fast and species composition tended to be simplified, and even dominant species of the habitats, regardless of type, changed significantly, more in the semi-natural habitat than in the cropland habitat; but the two types of habitats did not differ much in number of agro-tolerant species. In the semi-natural habitat, species richness and species composition did not change much, but urbanization led to loss of some of the semi-natural habitats, which would pose a threat to the maintenance of species composition. These findings indicate that agricultural intensification affected plant diversity in the suburban agricultural landscape significantly. However, the impact was relatively not so strong in the semi-natural habitats as in the cropland habitats. Obviously the semi-natural habitats may play an important role in protecting agriculture landscape plant diversity. Therefore, for conservation of plant diversity in the suburban agricultural landscape, it is essential not only to lower the degree of agricultural intensification by adopting more environmentfriendly measures, but also to strengthen conservation of semi-natural habitats in the process of urbanization.

Key words: agricultural intensification, urbanization, plant diversity, semi-natural habitat, spatio-temporal variation