Seasonal Variation in Leaf Litter Nutrient Concentrations of Valdivian Rainforest Trees (original) (raw)
Related papers
RESORPTION EFFICIENCY DECREASES WITH INCREASING GREEN LEAF NUTRIENTS IN A GLOBAL DATA SET
Ecology, 2005
To investigate effects of green-leaf nutrient status on senesced-leaf nutrient concentrations and resorption efficiency, we developed a database of nitrogen (N) and phosphorus (P) concentrations in green and senesced leaves from 92 published studies. We fit power functions (i.e., [nutrient] sen ϭ A [nutrient] ) separately for N and P. The database B gr encompassed 297 perennial species of different life-forms. Across these divergent species and conditions, a major control on senesced-leaf nutrient concentration was green-leaf nutrient status; nutrient concentrations in senesced leaves were positively associated with green-leaf nutrient concentrations (r 2 values from 51% to 84%). Within-species variation as well as species differences contributed to the overall variation in nutrient concentrations. Moreover, N and P resorption efficiency decreased, respectively, with increased N and P green-leaf status; fitted power functions indicated that a disproportionate amount of nutrient remained in senesced leaves of higher green-leaf nutrient status. Functional relationships between nutrient concentrations in senesced and green leaves were indistinguishable for evergreen and deciduous species, but evergreens tended to have lower concentrations in both senesced and green leaves. General relationships (across species and environments) between senesced-and green-leaf nutrient concentrations and broad, intraspecific variation in nutrient concentrations suggest that variation in resorption efficiency and proficiency could be a result (and not necessarily a cause) of species sorting across fertility gradients.
2005
Extensive variation in fractional resorption of mineral elements from plant leaves is still not fully understood. In multi-species forest stands, species leaf fall phenology and leaf constitution may significantly modify the timing of nutrient return to the soil and overall plant nutrient loss. We studied leaf fall and nutrient loss kinetics, and leaf composition in three natural, temperate, deciduous broadleaf forest stands to determine the role of timing of leaf abscission and nutrient immobilization in cell walls on nutrient resorption efficiency of senescing leaves. Nitrogen (N), phosphorus and potassium contents decreased continuously in attached leaves after peak physiological activity during mid-season. Changes in nutrient contents of attached leaves were paralleled by decreases in nutrient contents in freshly fallen leaf litter. In different species and for different nutrients, resorption of nutrients from senescing leaves proceeded with different kinetics. The maximum nutrient resorption efficiency (the fraction of specific nutrient resorbed from the leaves at the end of leaf fall) did not depend on the mid-seasonal nutrient concentration. Species with earlier leaf fall resorbed leaf nutrients at a faster rate, partly compensating for the earlier leaf fall. Nevertheless, the litter-mass weighted mean nutrient contents in leaf litter were still larger in species with earlier leaf fall, demonstrating an inherent trade-off between early leaf fall and efficient nutrient resorption. This trade-off was most important for N. Losses of the non-mobile nutrients calcium and magnesium were unaffected by the timing of leaf fall. There was large variation in the maximum N resorption efficiency among species. Correlations among leaf chemical variables suggested that the maximum N resorption efficiency decreased with the increasing fraction of cell walls in the leaves, possibly due to a greater fraction of N occluded in cell wall matrix. We conclude that species leaf fall phenology and leaf chemistry modify the timing and quantities of plant nutrient losses, and that more diverse forest stands supporting a spectrum of species with different phenologies and leaf types produce litter with more variable chemical characteristics than monotypic stands.
Canadian Journal of Botany, 2001
We examined 90 dry tropical tree species growing on contrasting soil types (relatively infertile Ultisol and more fertile Inceptisol) for leaf traits such as leaf habit, specific leaf mass (SLM, leaf dry mass per leaf area), leaf chemistry (nutrient concentrations and C/N ratios), and nutrient resorption. Across the species, SLM ranged from 4.06 to 15.74 mg·cm -2 in mature leaves and from 2.60 to 15.12 mg·cm -2 in senesced leaves. Mature leaf N and P concentrations varied from 0.86% to 4.11% and 0.13% to 0.21%, respectively. Senesced leaf N concentrations varied from 0.49% to 1.90% and P from 0.04% to 0.47%. Resorption efficiencies varied from 26% to 83% (mean = 58.32% ± 1.20%) for N and from 16% to 80% (mean = 49.57% ± 1.48%) for P indicating that the woody species of dry tropical environments resorbed different nutrients in substantial amounts to support new growth. Deciduous species had greater resorbed nutrient pools and resorption efficiencies than evergreen species. Compared with the nutrient-rich environment, species from the nutrient-poor environment had a lower resorbed P pool and lower resorption efficiencies for N and P, but had similar N and P concentrations in mature leaves. Resorption efficiencies for C, N, and P were generally correlated, suggesting that the resorbed C pool acted as a vehicle for mobilizing nutrients, especially N. Species with a low or high C/N ratio in senesced leaf and a low or high N resorption efficiency occurred in both nutrient-poor and nutrient-rich environments, as well as among deciduous and evergreen leaf habits, indicating individualistic adaptations to optimize the efficiency of nutrient resource use and conservation of the dry tropical woody vegetation.
Biotropica, 2011
The influence of environmental gradients on the foliar nutrient economy of forests has been well documented; however, we have little understanding of what drives variability among individuals within a single forest stand, especially tropical forests. We evaluated inter-and intra-specific variation in nutrient resorption, foliar nutrient concentrations and physical leaf traits of nine canopy tree species within a 1-ha secondary tropical rain forest in northeastern Costa Rica. Both nitrogen (N) and phosphorus (P) resorption efficiency (RE) and proficiency of the nine tree species varied significantly among species, but not within. Both N and P RE were significantly negatively related to leaf specific strength. Green leaf N and P concentrations were strongly negatively related to leaf mass per area, and senesced leaf nutrient concentrations were significantly positively related to green leaf nutrient concentrations. This study reveals a strong influence of physical leaf traits on foliar nutrient and resorption traits of co-occurring species in a secondary wet tropical forest stand.
Autumn nutrient resorption and losses in four deciduous forest tree species
Forest Ecology and Management, 2006
Nutrient resorption prior to leaf senescence is an important mechanism of nutrient conservation in forest tree species. However, despite the abundance of literature on the subject, inter-specific comparison of common temperate tree species is complicated by both the variability of resorption efficiency, which is affected by many environmental factors, and methodological differences between the studies, especially in relation to measurements of nutrient losses. This study compares the autumn nutrient resorption and nutrient losses via throughfall and litterfall of N, P, K, S, Mg, Ca, Cu, Fe and Mn in adjacent 40-year-old stands of Quercus robur L., Tilia cordata Mill., Fraxinus excelsior L. and Betula pendula Roth. In addition, the relative susceptibility of leaves to leaching was studied in the laboratory. For all species and elements, except K in ash stands, nutrient losses via throughfall were considerably lower than the losses via litterfall during the sampling period (from the end of August to the middle of October). Nutrient amounts in the throughfall were mostly governed by the susceptibility of the respective species to foliar leaching, which was highest in ash trees, but also depended on nutrient amounts in the pre-senescent leaves. K showed the highest losses via throughfall among the studied elements, 30% of the green leaf content being lost in the ash stand and 8-11% in the other stands. Ash also showed considerable throughfall losses (9-19% of green leaf content) of S, Mn, Mg, Ca and P, while the corresponding losses of these elements in other species were lower in relation to the nutrient content of their foliage. Species with higher amounts of nutrients in the green leaves tended to have higher amounts of nutrients in their litter, but this tendency was not observed for all species and elements. Nutrient resorption efficiency, calculated on leaf area basis, differed among species and was highest for N (ranging from 36% in ash to 69% in birch), P (from 37 in ash to 59% in lime), K (from 38% in ash to 51% in lime) and S (from 31% in ash to 48% in birch). Fe and Cu were the most efficiently withdrawn micronutrients (the amounts resorbed ranging from 7-10% in lime to 20-37% in the other species).
Polish Journal of Ecology, 2008
Gallery forests in Central Black Sea Region are dominated by Platanus orientalis L. The studies were performed in four sites (Mert River, Adalar, Kurupelit and Taflan Regions) located in V-shaped river valleys and differing with soil conditions. Nutrient concentrations were measured in green and senescent leaves in selected sympatric tree species. Foliar nutrient resorption efficiency (RE; as the ratio of the resorbed amounts of nutrient losses during the leaf senescence to its prior amount deposited in the leaves) and proficiency (RP; the level to which nutrient content per unit leaf mass, mg g–1, has been reduced in senescent leaves) were examined in several sympatric species. The high nitrogen resorption efficiency (N-RE) (62%) were found in Hedera helix L., while the lowest (40%) – in Salix alba L. The phosphorus resorption efficiency (P-RE) ranged between 35% (Rubus discolor Weithe and Nees) and 50% (S. alba) and that of potassium (K-RE) ranged between 49% (S. alba) and 62% (Ro...
Plant and Soil, 2006
The extent to which plant communities are determined by resource availability is a central theme in ecosystem science, but patterns of small-scale variation in resource availability are poorly known. Studies of carbon (C) and nutrient cycling provide insights into factors limiting tree growth and forest productivity. To investigate rates of tropical forest litter production and decomposition in relation to nutrient availability and topography in the absence of confounding large-scale variation in climate and altitude we quantified nutrient fluxes via litterfall and leaf litter decomposition within three distinct floristic associations of tropical rain forest growing along a soil fertility gradient at the Sepilok Forest Reserve (SFR), Sabah, Malaysia. The quantity and nutrient content of small litter decreased along a gradient of soil nutrient availability from alluvial forest (most fertile) through sandstone forest to heath forest (least fertile). Temporal variation in litterfall was greatest in the sandstone forest, where the amount of litter was correlated negatively with rainfall in the previous month. Mass loss and N and P release were fastest from alluvial forest litter, and slowest from heath forest litter. All litter types decomposed most rapidly in the alluvial forest. Stand-level N and P use efficiencies (ratios of litter dry mass to nutrient content) were greatest for the heath forest followed by the sandstone ridge, sandstone valley and alluvial forests, respectively. We conclude that nutrient supply limits productivity most in the heath forest and least in the alluvial forest. Nutrient supply limited productivity in sandstone forest, especially on ridge and hill top sites where nutrient limitation may be exacerbated by reduced rates of litter decomposition during dry periods. The fluxes of N and P varied significantly between the different floristic communities at SFR and these differences may contribute to small-scale variation in species composition.
Plant and Soil, 2005
The resorption of nutrients from senescing leaves is a key component of the nutrient conservation strategy of plants. Despite its relevance, the regulation of the efficiency of this process is poorly understood. The aim of this work was to test the hypothesis that species that shed leaves gradually along the year are less efficient reabsorbing nutrients from senescing leaves than species that shed leaves in a short period. N-, P-, and Kresorption-efficiencies were measured in 11 Mediterranean species and regressed against an index of the gradualness of leaf shedding. Additionally, the bivariate relations among leaf nutrient content before senescence, nutrient content in senesced leaves, pool of nutrients reabsorbed during senescence, and nutrient resorption efficiency, were examined. K-resorption-efficiency was markedly lower in species with protracted leaf-shedding, in agreement with the initial hypothesis. This pattern was less significant for Nand P-resorption-efficiencies. When leaf nutrient content before senescence was high, the amount of nutrients reabsorbed and the amount of nutrients in senesced leaves were high. Consequently, nutrient resorption efficiency was unaffected by the leaf nutrient status before senescence. It is concluded that the leaf shedding pattern per se influences nutrient resorption in Mediterranean perennials, irrespective of additional environmental controls. Furthermore, it is suggested that plants differing in nutrient status do not exhibit different nutrient resorption efficiencies because the nutrient content of leaves before senescence affects the components of resorption efficiency in countervailing ways.
2020
Author contributions: CJR and RSK led the writing of the manuscript and analyzed data. All authors designed the study and performed research. changed additively, suggesting minimal evidence for non-additive diversity effects on nutrient source/sink status. 5. Our results demonstrate that litter species identity can have whole-ecosystem effects on stream nutrient dynamics, with important implications for the form and fate of nutrients exported downstream. Further, diverse litter assemblages may serve as temporal stabilizers of ecosystem processes, such as nutrient sequestration, due to microbial nutrient requirements and differential decomposition rates, or the classic litter "processing continuum".
Nutrient Cycling in Forest Ecosystems
2020
Nutrient resorption from senescing leaves is one of the plants' essential nutrient conservation strategies. Parameters associated with resorption are important nutrient-cycling constraints for accurate predictions of long-term primary productivity in forest ecosystems. However, we know little about the spatial patterns and drivers of leaf nutrient resorption in planted forests worldwide. By synthesizing results of 146 studies, we explored nitrogen (N) and phosphorus (P) resorption efficiency (NRE and PRE) among climate zones and tree functional types, as well as the factors that play dominant roles in nutrient resorption in plantations globally. Our results showed that the mean NRE and PRE were 58.98% ± 0.53% and 60.21% ± 0.77%, respectively. NRE significantly increased from tropical to boreal zones, while PRE did not significantly differ among climate zones, suggesting differential impacts of climates on NRE and PRE. Plant functional types exert a strong influence on nutrient resorption. Conifer trees had higher PRE than broadleaf trees, reflecting the adaptation of the coniferous trees to oligotrophic habitats. Deciduous trees had lower PRE than evergreen trees that are commonly planted in P-limited low latitudes and have long leaf longevity with high nutrient use efficiency. While non-N-fixing trees had higher NRE than N-fixing trees, the PRE of non-N-fixing trees was lower than that of N-fixing trees, indicating significant impact of the N-fixing ability on the resorption of N and P. Our multivariate regression analyses showed that variations in NRE were mainly regulated by climates (mean annual precipitation and latitude), while variations in PRE were dominantly controlled by green leaf nutrient concentrations (N and P). Our results, in general, suggest that the predicted global warming and changed precipitation regimes may profoundly affect N cycling in planted forests. In addition, green leaf nutrient concentrations may be good indicators for PRE in planted forests.