Multiple nutrients limit litterfall and decomposition in a tropical forest.
To explore the importance of 12 elements in litter production and decomposition, we fertilized 36 1600 m(2)-plots with combinations of N, P, K, or micronutrients (i.e. B, Ca, Cu, Fe, Mg, Mn, Mo, S, Zn) for 6 years in a lowland Panamanian forest. The 90% of litter falling as leaves and twigs failed to increase with fertilization, but reproductive litter (fruits and flowers) increased by 43% with N. K enhanced cellulose decomposition; one or more micronutrients enhanced leaf-litter decomposition; P enhanced both. Our results suggest tropical forests are a non-Liebig world of multiple nutrient limitations, with at least four elements shaping rates of litterfall and decomposition. Multiple metallomic enzymes and cofactors likely create gradients in the break down of leaf litter. Selection favours individuals that make more propagules, and even in an N-rich forest, N is a non-substitutable resource for reproduction.
Kaspari
Michael
M
EEB Graduate Program, Department of Zoology, University of Oklahoma, Norman, OK 73019-0235, USA. mkaspari@ou.edu
Garcia
Milton N
MN
Harms
Kyle E
KE
Santana
Mirna
M
Wright
S Joseph
SJ
Yavitt
Joseph B
JB
D002482:Cellulose / Q000378:metabolism; D017753:Ecosystem; D005308:Fertilizers; D018977:Micronutrients / Q000494:pharmacology; D009584:Nitrogen / Q000494:pharmacology; D010758:Phosphorus / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D014197:Trees / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D014329:Tropical Climate
D005308:Fertilizers; D018977:Micronutrients; D010758:Phosphorus; D002482:Cellulose; D009584:Nitrogen; D011188:Potassium