Ecology Of Fine Roots Of Casuarina Equisetifolia Plantation On Coastal Sand

Casuarina equisetifolia, introduced abroad into China in 1950s, has been showing good adaptability and high productivity. It play an important role in wind break and sand fixation, ameliorating ecological environment and offering timber along the southeast coast in China. To some extent, it has become one of the irreplaceable plantations in protecting plantation, particularly on the wind gap site. However, littoral situated at the area where terrene marched with ocean, the gigantic change of climate here is easily result in disaster weather, typhoon, rainstorm, storm tide, drought and water logging raid the seashore and around area, as well as the jamming, made the ecological condition in this area is weak. The unreasonable management and the bad influences of nature factors led to single component and irrational structure of Casuarina equisetifolia forest belt, and result in aging early, stunting young, and low-value and low-effectiveness in preventing. This exerts negative influences for the sustainable development of coastal protection forest system. Many researchers focus their studies on the rational structure and function of sustainable coastal protection forest of Casuarina equisetifolia, try to reveal the contributing factors to cause low-value and low-effective forest and probe into its mechanisms. All these studies put scientific basic for rational management for sustainable coastal protection forest of Casuarina equisetifolia, and meet the demand of the construction of coastal prevent system project.Although great number of relative studies have reported that fine roots play an important role in nutrient cycling and energy flow in forest ecosystems, studies at home lag behind theirs for two or three decades and have no adequate understanding of the role. Casuarina equisetifolia which is planted on the coastal sand can endure drought, barren and struggle against salt and alkali. These functions are surely related to its biology characteristic, especially fine roots characteristic. On the other hand, roots, especially fine roots' absorption of water and nutrient will subsequently affect above-ground growth. This research carried out an systemic discuss on fine roots ecology based on the actuality that pay much more attention to above-ground while less to below-ground. The research was carried out from January 2005 to January 2006 at Chihu protection forest farm, Hui'an Country and Chishan protection forest farm, Dongshan Country, Fujian by using sequential soil core method to observe the following aspects: (1) the standing crops of fine-roots biomass, nutrient and energy, their seasonal dynamics and changes with age; (2) fine roots distribution; (3) net productivity, turnover and decomposition of fine roots; (4) nutrient and energy return and release from fine roots during decomposition. From this study, we get these results as follows:...