关键词: 水稻, 适宜播期, 知识模型, 专家系统

Abstract: Cordgrasses (Spartina spp.), perennial plant species belonging to genus Spartina of Family Graminoae, mainly grow in coastal salt and muddy intertidal flats. In this paper, the recent progresses in assessing cordgrass ecological functions and population expansion controlling were reviewed. As alien invasive species, cordgrass species, on one hand, were now threatening local biodiversity and further influencing social-economic sustainable development in many regions and countries. On the other hand, they played important roles in preventing coastal erosion and accelerating silt deposition, and this positive function should be emphasized especially under the condition of future sea level rising resulted from global warming. Among the ecological measures of controlling cordgrass expansion, chemical herbicide can eliminate large area of cordgrass community rapidly, but with possible side effects of soil pollution. Physical measures are too costly to be appropriate to large community. Biocontrol looks promising, but it does not work well until now and it will cause secondary biological invasion. Moreover, 3S (GPS, RSand GIS) technology, mathematical models of population growth and dispersal, and long-term monitoring systems have been employed in smooth cordgrass monitoring and controlling. We finally proposed several suggestions on how to strengthen fundamental research for ecological control and how to assess cordgrass ecosystem benefits.

Key words: Rice, Suitable sowing date, Knowledge model, Expert system