| Tallgrass prairies and savannas are some of the most endangered ecological communities in Canada, with approximately 1 percent of their original extent remaining. Tallgrass communities once covered a significantpart of southern Ontario's landscape. Owing to degradation and destruction through urban development, agriculture, pollution and mismanagement, less than 3 percent of the original extent remains in the region, with most remnants existing in small, isolated patches. As these highly diverse communities themselves are rare and threatened, so too are many of the wildlife species which depend on these communities for their survival. Interest in conserving and restoring Ontario's tallgrass communities and their resident wildlife is on the rise in Ontario. However, forestland and agriculture land owned by private sectors would be impossible to restored as tallgrass prairie. Yet restoration on right –of-way would be fesible, and thereby would enhance the landscape diversity biodiversity.This project is testing the feasibility of deliberate establishment of native prairie-like vegetation on hydro rights-of-way in Southern Ontario, and specifically in the Region of Kichener-Waterloo, basing on the initiate study leading by Dr. Suffling, University of Waterloo. The experiment involves 64 main research plots, each 5 x 5m, established in 1996 at the Detweiler Transformer Station, Kitchener, Ontario. Plots are arranged in a factorial randomised block with 4 methods of site preparation (No Preparation, Fall Glyphosate herbicide [1% in water applied at 380l/ha], Spring Glyphosate herbicide and Fall & Spring Rototilling), as well as 4 methods of management (Burned, Mowed, and Mowed & Burned, and Unmanaged). Each experiment of 16 treatments was replicated 4 times. Principal Component Analysis (PCA) was employed to compare the process of temporal and spatial sucession using Compose and CANOCO program developed by Conell University, while biodiversity examined with Simpson Index and Shannon-veiner Index.The results show that Andropogon gerardii (Big bluestem) and Sorghastrum nutans (Indian grass) started to habitate in 1998. The coverage of big bluestem increases greatly in 2002 in treatment 5 Spring Glyphosate herbicide & Mowing, 6 tillage & fire, 7 spring herbicide & fire, 9 spring herbicide & no-land preparation, 10 spring herbicide & mowing& fire, 11 tillage& no-land preparation, 12 tillage &mowing, 16 tillage&fire&mowing.The outcome of PCA demonstrates that it is changing significantly in temporal process, which longest distant among the treatments in 1997, and shortest in 2002. Comparing the distances of different land preparation and managements, it is found that the gap among land preparation treatments is widest in 1997 and 1998, but getting closer in 2002, while it didn't showed significant difference among management treatment in 1997 and 1998, but lightly difference in 2002. These results reveal that in the first several years of restoration, land preparation is the crucial factors for the grass communities changing, which is faciliate to tallgrass species habitation, while due to lack of enough thatch layer, manaments method, i.g mowing and fire, are not affect the succession significantly. The result of biodiversity analysis aslo shows that both Simpson Index and Shannon-viener Index are significantly different between land preparations and none preparation. Biodiversities increase in all land preparation treatment. Conclusionly, spring herbicide and tillage can accelerate the prairie dominent species Andropogon gerardii and Sorgarstrum nutans to habitate and generate, and conversely resist the Europe species Poa pratensis to grow. Mowing dons't contribute evidently for the native species growing. Fall herbicide and fire help Solidago species to compete other species. In the first few year of restoration, land preparation will be more important than management such as fire, mowing to affect the construction of prairie community.
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