互花米草群落功率最大化倾向

Maximizing empower of Spartina alterniflora community

植物新种进入新区域后,通过扰动或搅局,改变生态系统的结构,形成有特色的自组织生态系统,趋向新条件下的功率最大化.本文应用能值分析的方法,分别对苏北互花米草生态系统和光滩生态系统进行能值分析和系统评估.结果表明:互花米草生态系统每年能值产出比光滩生态系统高1.52E+18sej.能值密度是光滩的4.72倍,基础能值产出率约为光滩生态系统的5倍.互花米草生态系统能更有效地利用能量,增加系统内部的能值贮存,实现系统内部的功率最大化.互花米草入侵某区域滩涂后,通过自组织促使整个互花米草生态系统趋于功率最大化,充分发挥生态服务功能,但由于其繁殖扩散过快,导致种群爆发,产生了一系列负面效应,如抑制本土物种、侵占航道、危害贝类养殖等.

When a new plant species is introduced to a new district,its disturbance could alter the structure of original ecosystem,resulting in the formation of a distinctive self-organized ecosystem to develop the maximizing empower under the new situation.In this paper,an emergy analysis method was made on the two ecosystems Spartina alterniflora salt marsh and mudflat in North Jiangsu.Compared with the mudflat,S.alterniflora ecosystem had a 1.52E ＋ 18 sej higher annual total emergy output,4.72 times of emergy density,and about 5 times of base emergy yield ratio.S.alterniflora ecosystem could use the energy more efficiently to increase its emergy storage and to realize it self＇s empower maximizing.After invading into a tidal flat ecosystem,S.alterniflora via self organization could promote the ecosystem to achieve empower maximizing,and to full play its ecological services.However,too fast propagation and spread could induce a series of negative effects,such as inhibiting native plants,trenching on sea-route,and endangering the seashells breeding,etc.