红树林凋落物生产及其归宿

Abstract

红树林具有很高的凋落物生产量,其生产量受到纬度、潮汐、海水盐度以及气象参数等多方面因素的影响,并且表现出明显的季节性变化规律。红树林凋落物有4条主要归宿:一部分被底栖动物摄食,主要是蟹类和腹足类;一部分被微生物直接分解;还有一部分以可溶性有机物或是以植物组织的形式输出到毗邻生态系统;余下的则以难分解的或是合成物质的形式进入到红树林底质。国内关于红树林凋落物的研究很多只从定性的角度揭示红树林凋落物的归宿,而缺少定量的实验研究,因而对凋落物各归宿的相对重要性缺乏正确认识。以前的一些研究忽视了底栖动物的作用,未来的研究应该更加注重红树林生态系统的开放性,定量研究凋落物的归宿,关注底栖生物在红树林凋落物周转过程中的作用,本文期待为正确揭示红树林凋落物的真实归宿提供思路。

Mangrove forest has high productivity of litterfall,which is affected by latitude,tide,seawater salinity,and meteorological parameters,and presents an obvious seasonal variation pattern.The mangrove litterfall has four fates,i.e.,(1) ingested by benthic fauna,mainly crabs and gastropods,(2) directly decomposed by microorganisms,(3) exported to other adjacent ecosystems in the forms of dissoluble organic matter or fresh plant parts such as leaves or propagules,and(4) deposited into mangrove sediments in the forms of less soluble or synthesized materials.The previous studies on the mangrove litterfall in China were mostly qualitative rather than quantificational,and thus,lacked in well understanding the relative importance of the each fate.Furthermore,some of the previous studies ignored the roles of benthic fauna.It was proposed that in the future studies,more attention should be paid to the openness and dynamic natures of mangrove ecosystem,the quantificational tracing of the fates of mangrove litterfall,and the roles of benthic fauna in the turnover of mangrove litterfall.