The Study Of Excavation Algorithm In Three-Dimensional Roadway Based On The Tetrahedral Mesh

Wetland is in the transition zone of terrestrial ecosystem (such as forest and grassland)and aquatic ecosystem (such as deep lakes and ocean); due to that, the unique ecosystem,which is different from terrestrial and aquatic ecosystems, has been formed. The wetland iswidely distributed all over the world and it has the great highest value economics, ecologyand society; except that the ecological functions of wetland which cannot be replaced bythe terrestrial and aquatic ecosystems. The area of wetland in China has reached10%of thearea of wetland on the world, which is the top of Asia and fourth place on the world;therefore China is a really huge country of the wetland resource.The protection of wetland is not valued for a long time in China and there are manyproblems in the protection of wetland. In China, there is not a speciallaw for the protectionof wetland, in the same time some provisions of the protection of wetland are too dispersiveand it is very difficult to coordinate those provisions; even, there are some provisions areunfavorable to the protection of wetland. In fact, the unreasonable development of thewetland causes the sharp cutoff of the natural wetland, the loss of wetland landscape, andthe decline of the environmental quality of wetland. Meanwhile, the excessive use of thenature resource takes the damage of the biodiversity and the decline of function of thewetland.Since China entered into the <ramsar convention on wetlands> in1992, how to protectand utilize the wetland resource became a new research subject in China. The basicapproach for solving the problems in the protection and utilization of the wetland is usingthe law to regulate the development, utilization, protection and management of the wetland.However, there are very few legal researches of wetland protection have been done inChina; even there is not a speciallaw for protecting the wetland. In2010, the CentralCommittee of China Association for Promoting Democracy proposed a motion, which wasthe suggestion for enacting and issuing the <Regulation for Wetland Protection>as early aspossible, at the third Session of the11th National Committee of the Chinese People’sPolitical Consultative Conference.In this article, the author revealed the crisis of wetlands protection in this countryaccording to the current situations of wetland protection in China and referred the researchfindings at home and abroad. In order to provide the useful suggestions for enacting and perfecting the special law of wetland protection in China, the author expounded the issuesrelate to the protection and legislation of wetland resource from the aspects of choice of theorder of law, the model of legislation, legislative justification range, legislative purposesand principles, and the perfection of law.