TY - JOUR
T1 - Species-soil associations, disturbance, and nutrient cycling in an Australian tropical rainforest
AU - Gleason, Sean Michael
AU - Read, Jennifer
AU - Ares, Adrian
AU - Metcalfe, Daniel
PY - 2010
Y1 - 2010
N2 - Resource availability and disturbance are important factors that shape the composition, structure, and functioning of ecosystems. We investigated the effects of soil fertility and disturbance on plant-soil interactions and nutrient cycling in a diverse tropical rainforest. Our goal was to determine how common soil specialisation is among species and how plant-soil interactions affect ecosystem functioning in the presence of disturbance. Most species (59 ) showed significant fidelity to either fertile (basalt) or infertile (schist) soils. Obligate schist specialists (six species) contributed 39 and 37 to total stand-level basal area and aboveground net primary productivity, respectively. High nutrient use efficiency of schist specialists reduced the rates of within-stand nutrient cycling through the production of nutrient-poor plant tissues and litter. Although forests on schist soils had higher basal area and similar rates of productivity to forests on basalt, uptake of Mg, K, P, and N were markedly less on schist than on basalt, particularly after a cyclone disturbance. Stands on schist soils were also less affected by the cyclone and, as a result, contributed less (ca. 50 ) Mg, K, P, and N inputs to the forest floor (via litterfall) than stands on basalt soils. System openness (i.e. the risk of nutrient loss) from cyclone-affected basalt forests was minimised by high rates of uptake following disturbance and large effective cation exchange capacities of soils. Soil-plant-disturbance interactions are likely to engender different fitness-enhancing strategies on fertile and infertile soils, possibly leading to the development and/or maintenance of diversity in rainforests.
AB - Resource availability and disturbance are important factors that shape the composition, structure, and functioning of ecosystems. We investigated the effects of soil fertility and disturbance on plant-soil interactions and nutrient cycling in a diverse tropical rainforest. Our goal was to determine how common soil specialisation is among species and how plant-soil interactions affect ecosystem functioning in the presence of disturbance. Most species (59 ) showed significant fidelity to either fertile (basalt) or infertile (schist) soils. Obligate schist specialists (six species) contributed 39 and 37 to total stand-level basal area and aboveground net primary productivity, respectively. High nutrient use efficiency of schist specialists reduced the rates of within-stand nutrient cycling through the production of nutrient-poor plant tissues and litter. Although forests on schist soils had higher basal area and similar rates of productivity to forests on basalt, uptake of Mg, K, P, and N were markedly less on schist than on basalt, particularly after a cyclone disturbance. Stands on schist soils were also less affected by the cyclone and, as a result, contributed less (ca. 50 ) Mg, K, P, and N inputs to the forest floor (via litterfall) than stands on basalt soils. System openness (i.e. the risk of nutrient loss) from cyclone-affected basalt forests was minimised by high rates of uptake following disturbance and large effective cation exchange capacities of soils. Soil-plant-disturbance interactions are likely to engender different fitness-enhancing strategies on fertile and infertile soils, possibly leading to the development and/or maintenance of diversity in rainforests.
UR - http://www.springerlink.com/content/m895qg708106g201/fulltext.pdf
U2 - 10.1007/s00442-009-1572-2
DO - 10.1007/s00442-009-1572-2
M3 - Article
SN - 0029-8549
VL - 162
SP - 1047
EP - 1058
JO - Oecologia
JF - Oecologia
IS - 4
ER -