title: Ecophysiological and foliar nitrogen concentration responses of understorey Acacia spp. and Eucalyptus sp. to prescribed burning.
abstract: Eucalyptus spp. is a dominant tree genus in Australia and most Eucalyptus spp. are canopy dominant species. In Australian natural forests, Eucalyptus spp. commonly are associated with understorey legumes which play a crucial role for ecological restoration owing to their nitrogen (N) fixing ability for replenishing the soil N lost after frequent prescribed burning. This study aimed to explore to what extent physiological responses of these species differ 7 and 12 years after last fire. Two most common understorey Acacia spp., Acacia leiocalyx and A. disparrima, as well as one non-leguminous Eucalyptus resinifera, were studied due to their dominance in the forest. Both A. leiocalyx and A. disparrima showed higher carbon (C) assimilation capacity, maximum photosynthetic capacity, and moderate foliar C/N ratio compared with E. resinifera. A. leiocalyx showed various advantages compared to A. disparrima such as higher photosynthetic capacity, adaptation to wider light range and higher foliar total N (TNmass). A. leiocalyx also relied on N2-fixing ability for longer time compared to A. disparrima. The results suggested that the two Acacia spp. were more beneficial to C and N cycles for the post burning ecosystem than the non-N2-fixing species E. resinifera. A. leiocalyx had greater contribution to complementing soil N cycle long after burning compared to A. disparrima.
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry, South China Agricultural University, Guangzhou, 510642, People's Republic of China.
authors.forename: Ling
authors.initials: L
authors.lastname: Ma
authors.forename: Xingquan
authors.initials: X
authors.lastname: Rao
authors.forename: Ping
authors.initials: P
authors.lastname: Lu
authors.forename: Shahla Hosseini
authors.initials: SH
authors.lastname: Bai
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Xu
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Chen
authors.forename: Timothy
authors.initials: T
authors.lastname: Blumfield
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
mesh_terms: D000045:Acacia / Q000737:chemistry*; D000393:Air Pollutants / Q000032:analysis*; D001315:Australia; D017753:Ecosystem; D005052:Eucalyptus / Q000737:chemistry*; D005390:Fires; D016468:Forestry / Q000379:methods; D008027:Light; D009584:Nitrogen / Q000032:analysis*; D010788:Photosynthesis / Q000502:physiology; D018515:Plant Leaves / Q000737:chemistry*; D012987:Soil; D014197:Trees
chemical_list: D000393:Air Pollutants; D012987:Soil; D009584:Nitrogen