Effects of experimental nitrogen additions on plant diversity in tropical forests of contrasting disturbance regimes in southern China.
Responses of understory plant diversity to nitrogen (N) additions were investigated in reforested forests of contrasting disturbance regimes in southern China from 2003 to 2008: disturbed forest (with harvesting of understory vegetation and litter) and rehabilitated forest (without harvesting). Experimental additions of N were administered as the following treatments: Control, 50 kg N ha(-1) yr(-1), and 100 kg N ha(-1) yr(-1). Nitrogen additions did not significantly affect understory plant richness, density, and cover in the disturbed forest. Similarly, no significant response was found for canopy closure in this forest. In the rehabilitated forest, species richness and density showed no significant response to N additions; however, understory cover decreased significantly in the N-treated plots, largely a function of a significant increase in canopy closure. Our results suggest that responses of plant diversity to N deposition may vary with different land-use history, and rehabilitated forests may be more sensitive to N deposition.
Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510160, China.
Xiankai
X
Lu
Jiangming
J
Mo
Frank S
FS
Gilliam
Guirui
G
Yu
Wei
W
Zhang
Yunting
Y
Fang
Juan
J
Huang
D000393:Air Pollutants / Q000633:toxicity*; D044822:Biodiversity; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D009584:Nitrogen / Q000032:analysis / Q000633:toxicity*; D063245:Plant Development; D010944:Plants / Q000145:classification / Q000187:drug effects*; D014197:Trees / Q000145:classification / Q000187:drug effects* / Q000254:growth & development; D014329:Tropical Climate
D000393:Air Pollutants; D009584:Nitrogen