Pulling Resistance and Modeling of Dominant Plants in Limestone Mining Spoils

摘要

In South Taiwan, staged open-cut mining method was adopted for industry of limestone mining. Such improper cutting method results in a large area of original plantation removal, creates a large volume of spoils, and consequently, causes serious impact on the ecological environment of the entire mining area. The vegetated hill slope always possesses a layer of topsoil for capable protection against soil erosion to stabilize the slope of a certain extent. To mitigate the influence of the improper mining activity, we improve the overall environment by vegetation with dominant plants in the local area. After vegetating treatment and succession, the important woody dominant plants are Dense-flowered False-nettle (Boehmeria densiflora Hook. & Arn.), Roxburgh sumac (Rhus javonica L. var. roxburghiana. DC.) and Pluchea (Pluchea carolinensis (Jacq.) G. Don) in South-Taiwan limestone spoil area. The roots of plants could be restraining the occurrence of shallow landslides because of mechanical reinforcing force of roots, and friction of roots-soil binding. These three plants were selected to obtain root-strength model from pulling resistance. The statistical regression analysis was performed to formulate the relationships of pulling resistance of root system (Pr), the growth characteristics of plants and field site environment with the testing results. Good regression relationships were obtained, thus, that served as an economical vegetation material at mining waste dumping area.