|SCHOONOVER, JON - Southern Illinois University
|WILLIARD, KARL - Southern Illinois University
Submitted to: Environment and Natural Resources Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/24/2016
Publication Date: 9/12/2016
Citation: Nelson, A.M., Schoonover, J.E., Williard, K.W. 2016. Nutrient dynamics and decomposition of riparian Arundinaria gigantea (Walt.)Muhl. leaves in southern Illinois. Environment and Natural Resources Research. 6(3):106-115.
Interpretive Summary: The leaf litter quality and quantity from the plants in the areas adjacent to streams (riparian zones) can influence soil nutrient dynamics and stream productivity. When leaves fall, they add nutrients to soils through decomposition and to streams as direct external inputs. The quantity and quality of the nutrients are dependent on leaf composition both before and after the leaf falls and the subsequent decomposition conditions. The volume and composition of fallen leaves from giant cane [Arundinaria gigantea (Walt.) Muhl.] stands in Southern Illinois were measured and analyzed. Leaf litter was collected from five established canebrakes monthly over one year and a decomposition study was conducted over 72 weeks. Live leaves, freshly senesced leaves, and decomposed leaves were analyzed for carbon and nitrogen content. The quantity of leaf litterfall biomass peaked in November at twice the monthly average volume for all but one site, indicating a resemblance to deciduous leaf fall patterns. Though canebrakes may deposit a lower annual litter load, the leaves dropped year round as opposed to the predominantly fall deposition of deciduous trees in the forests. Therefore, giant cane supplies nutrients throughout the year to both the soil and the adjacent stream. Because giant cane may supply nutrients to macroinvertebrates for a longer period of time and year round, it should be considered in multispecies riparian buffers.
Technical Abstract: Leaf litter quality and quantity can influence soil nutrient dynamics and stream productivity through decomposition and serving as allochthonous stream inputs. Leaf deposition, nitrogen (N)-resorption efficiency and proficiency, and decomposition rates were analyzed in riparian stands of Arundinaria gigantea (Walt.) Muhl. in southern Illinois for the first time. Leaf litter was collected from five established canebrakes monthly over one year and a decomposition study was conducted over 72 weeks. Live leaves, freshly senesced leaves, and decomposed leaves were analyzed for Carbon (C) and N content. Leaf litterfall biomass peaked in November at twice the monthly average for all but one site, indicating a resemblance to deciduous leaf fall patterns. Nitrogen and carbon levels decreased 48% and 30%, respectively, between live leaves and 72 weeks following decomposition. High soil moisture appeared to slow decomposition rates, perhaps due to the creation of anaerobic conditions. Cane leaves have low resorption proficiency and nutrient-use proficiency, suggesting that these riparian canebrakes are not N limited.