Changes in the benthic protozoan community during succession of a mangrove ecosystem in Zhanjiang, China

Abstract

The protection and restoration of mangrove ecosystems depend on understanding the interaction between benthic organisms and mangrove succession. Although benthic protozoa are important in such ecosystems, protozoan community dynamics have seldom been studied during the mangrove succession. The benthic protozoa of a mangrove chronosequence that included a primary community (unvegetated shoal), an early community (Avicennia marina), a middle community (Aegiceras corniculatum), and a late community (Bruguiera gymnorrhiza + Rhizophora stylosa) were investigated to determine the changes in the benthic protozoan community during a mangrove succession at Zhanjiang, China. A total of 62 benthic protozoa taxa belonging to three classes, 26 orders, and 38 families were recorded. The abundance of benthic protozoa decreased significantly during mangrove succession, while species richness and diversity changed irregularly. Hierarchical clustering indicated that the distribution of the benthic protozoa closely corresponded with the mangrove successional stages. Further analyses indicated that the changes in the benthic protozoan community with mangrove succession were associated with the changes in total sediment nitrogen content and especially with vegetation characteristics, including plant height and crown breadth. The decline in the abundance of benthic protozoa during mangrove succession may be explained by the deterioration of benthic protozoan microhabitats. However, determining whether these or other factors are responsible for the change in the benthic protozoan community during mangrove succession will require additional research.

Dominant protozoan species in rhizosphere soil over growth of Beta vulgaris L . in Northeast China

“…The soil ciliate has been identified with the non-flooded Petri dish method with pre-dried then reactivated resting cysts of the ciliates [14]. This method was applied for estimating the species richness of benthic protozoan community in a mangrove site [15], of testate amoebae species from moss samples collected at high altitude Himalayan region [16], and of ciliate species in soil samples collected in Brazil and China [17]. Commonly only the ones that can survive after drought storage and can revive will be counted.…”

Identifying trait‐based tolerance to sediment dynamics during seedling establishment across eight mangrove species

“…While the impact of abiotic drivers such as salinity and inundation on seedling establishment has been studied for numerous mangrove species (Ball and Pidsley 1988;Ye et al 2005;Krauss et al 2008), impact of mechanical disturbance from sediment dynamics has only been quantified for two mangrove species, namely the pioneer species Avicennia alba and Sonneratia alba (Balke et al 2013; but see Cao et al 2018;Redelstein et al 2018 for saltmarsh species). Natural forest expansion as well as restoration often take place at the forest fringe where seedlings are exposed to mechanical disturbance from tides, waves, and sediment dynamics (Balke et al 2011(Balke et al , 2013Chen et al 2018). The latter can result in sediment accretion or erosion, with an order of magnitude of 1 cm d À1 in the pioneer zone (Hu et al 2020), and strongly affect seedling survival (Terrados et al 1997;Ellison 1999).…”