Assessment For Plants Along The Route Impacted By Freeway Construction

Construction of the freeway destructs seriously the ecological environment along the route. And the plants can mostly indicate the condition of the environment. Therefore, researching the physiological and biochemical indexes of the plants impacted by freeway construction, on the one hand, can select the plants which have prevalent fastness by intimidated in freeway construction, on the other hand, can establish effective index measuring system about destructs and resume of ecological environment, which will support theoretically for the afforestation and ecological reconstruction of the freeway. Before researching the relationship, it is need to know how to select the ecological, physiological and biochemical indexes of the plants to reflect the influence to the plants by construction of the freeway. The related studies were conducted in four monitored plots (three polluted plots and one compared plot) on the way of the construction of Suizhou-Yueyang freeway in April, 2006 and April, 2007 to these problems. The main results were as follows:1. Among the six physiological and biochemical indexes of the plants that this thesis presents, the activation of NR is most sensitive index to the impact by freeway construction, While the activation of SOD and the content of chlorophyll is the most stable index to the impact by freeway construction. By Making principal component analysis to the six physiological and biochemical indexes, the indexes which have strong impact on the first principal component are the content of chlorophyll, the activation of NR, the photosynthetic and the respiration. Because these four indexes are related to getting and using resource (the light and the NO3"). The indexes which have strong impact on the second principal component are the activation of SOD and the content of dissoluble protein. Because these two indexes are related to the physiological and biochemical movement. When assessing the plants' physiological and biochemical change impacted by freeway construction, it can select the activation of NR(the first principal component) and the activation of SOD(second principal component) for research,but unnecessary to measure all six parameters.2. Taking fifteen kinds of plant in the quadrat of Qianchang which suffered by the heaviest freeway construction impact in this study for example, the poor resistance species include Robinia pseudoacacia L. and other eight kinds of species. The pollution prevention species include Melia azedarach L. and other five kinds of species. Obviously, the Melia azedarach L. is the best pollution prevention species in this study and It can be used to afforest and ecological reconstrustion of the freeway. Whereas other pollution prevention species, if their seeds can be easily got, can be used to afforest and ecological resconstruction of the freeway. In addition, The poor resistance species Robinia pseudoacacia L. can be firstly used as the sample for construction impact research, while the other poor resistance species can also be used as the sample for construction impact research when combining other ecologcal paraments. When assessing the plants along the rout impacted by freeway construction, the poor resistance species should firstly be selected as the sample for construction impact research, while the pollution prevention species should be used to afforestation and ecological reconstruction of the freeway.