Soil nitrogen in relation to quality and decomposability of plant litter in the Patagonian Monte, Argentina
| Autor: | Carrera Analía Lorena, Vargas Dariana Noé, Campanella María Victoria, Bertiller Mónica Beatriz, Sain Claudia Leticia, Mazzarino María Julia |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2005 |
| Předmět: |
PERENNIAL GRASSES
geography geography.geographical_feature_category Ecology Perennial plant Plant Science Evergreen Plant litter Biology N MINERALISATION Shrubland EVERGREEN SHRUBS Plant ecology Plant life-form Agronomy CIENCIAS AGRÍCOLAS Botany Litter Ecosystem DECOMPOSITION RATE CONSTANTS Otras Ciencias Agrícolas PHENOLIC COMPOUNDS LIGNIN |
| DOI: | 10.1007/s11258-005-5322-9 |
| Popis: | In two consecutive years, we analysed the effect of litter quality, quantity and decomposability on soil N at three characteristic sites of the Patagonian Monte. We assessed (i) concentrations of N, C, lignin and total phenolics and the C/N ratio in senesced leaves as indicators of litter quality of three species of each dominant plant life form (evergreen shrubs and perennial grasses), and (ii) N, and organic-C concentrations, potential N-mineralisation and microbial-N flush in the soil beneath each species. Rate constants of potential decomposition of senesced leaves and N content in decaying leaves during the incubation period were assessed in composite samples of the three sites as indicators of litter decomposability. Further, we estimated for each species leaf-litter production, leaf-litter on soil, and the mass of standing senesced leaves during the senescence period. Senesced leaves of evergreen shrubs showed higher decomposability than those of perennial grasses. Leaf-litter production, leaf-litter on soil, and the mass of standing senesced leaves differed significantly among species. The largest variations in leaf-litter production and leaf-litter on soil were observed in evergreen shrubs. The mass of standing senesced leaves was larger in perennial grasses than in evergreen shrubs. Nitrogen, organic C and potential N-mineralisation in soil were higher underneath evergreen shrubs than beneath perennial grasses, while no significant differences were found in microbial-N flush among life forms. The initial concentrations of C, N and total phenolics of senesced leaves explained together 78% of the total variance observed in the dry mass loss of decaying leaves. Litter decomposition rates explained 98%, 98%, 73%, and 67% of the total variance of soil N, organic C, net-N mineralisation, and microbial-N flush, respectively. We concluded that leaf-litter decomposition rates along with leaf-litter production are meaningful indicators of plant local effects on soil N dynamics in shrublands of the Patagonian Monte, and probably in other similar ecosystems of the world dominated by slow growing species that accumulate a wide variety of secondary metabolites including phenolics. Indicators such as C/N or lignin concentration usually used to predict litter decomposability or local plant effects may not be adequate in the case of slow growing species that accumulate a wide range of secondary metabolites or have long leaf lifespan and low leaf-litter production. Fil: Carrera, Analía Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Vargas, Dariana Noe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Campanella, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Bertiller, Monica Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Sain, Claudia Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Mazzarino, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|