title: Recovery of macrobenthos in defaunated tropical estuarine sediments.
abstract: In the estuarine environment, hypoxia and/or anoxia have become a major cause of benthic defaunation and are strongly associated with increased eutrophication. Mesoscale field experiments were carried out to examine the recolonization and recovery time of macrobenthos after defaunation. Azoic sediments were achieved by covering four areas with polyethylene sheeting. Temporal changes and depth distribution of macrobenthos within the defaunated sediments were compared with those in undisturbed natural sediments at the same site. Within 3 days, annelids appeared as the first immigrants. After 153 days, the process of recovery had not yet been completed in terms of species richness. Whereas diversity and evenness showed no significant differences between treatments during the entire experiment, multivariate analyses proved that differences between treatments were still significant 93 days after the start of the experiment.
authors: Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros s/n, Dois Irmãos 52171-900, Recife-PE, Brazil. monica.botter@db.ufrpe.br
authors: Mônica L
authors: ML
authors: Botter-Carvalho
authors: Paulo V V C
authors: PV
authors: Carvalho
authors: Paulo J P
authors: PJ
authors: Santos
mesh_terms: D000818:Animals; D000845:Annelida / Q000254:growth & development / Q000502:physiology; D001938:Brazil; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005618:Fresh Water; D019015:Geologic Sediments / Q000737:chemistry*; D007448:Invertebrates / Q000145:classification / Q000254:growth & development / Q000502:physiology*; D008386:Marine Biology / Q000379:methods*; D015999:Multivariate Analysis; D020959:Polyethylene / Q000737:chemistry; D012623:Seawater; D013997:Time Factors; D014329:Tropical Climate
chemical_list: D020959:Polyethylene