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1.
Pablo G. Aceñolaza Lisandra P. Zamboni Estela E. Rodriguez Juan F. Gallardo 《Annals of Forest Science》2010,67(3):311-311
2.
? Context
The rising demand of energy wood for heating purposes in Germany leads to concerns regarding the overexploitation of forests. A major aspect is the impact of whole-tree harvesting on long-term productivity of forest soils.? Aims
This study aimed to analyze the effects of nutrient removal on productivity using the historically prevalent practice of litter raking. Since there is a lack of controlled whole-tree harvesting experiments in Germany, we used litter raking as a surrogate management practice entailing the removal of nutrients from forest stands.? Methods
We used three sites with documented litter raking to analyze the effects of nutrient removal on productivity using dendroecological methods: two recent litter removal experiments in two Scots pine stands (Siegenburg and Burglengenfeld) and one oak stand (Eichhall) with documented historic litter raking. Basal area increment (BAI) and tree-ring characteristics were compared between periods with litter raking and the preceding periods for both treatment and control plots.? Results
For the two Scots pine sites with a relatively short litter raking period, no effects of litter raking on BAI could be ascribed to nutrient removal. On the oak site with a longer history of litter utilization, the loss in BAI due to litter raking amounts to 22 % during the period with active raking and to still 17 % in the recovery period.? Conclusions
These results contribute to the still very limited understanding about the impact of whole-tree harvesting on forest productivity in Germany by laying down an upper limit of possible effects due to nutrient removal, as nutrient loss by litter raking tends to be higher than nutrient loss by whole-tree harvesting. 相似文献3.
Litterfall and litter chemistry change over time in an old-growth temperate forest, northeastern China 总被引：1，自引：0，他引：1
4.
Teresa Bueis Felipe Bravo Valentín Pando María Belén Turrión 《Annals of Forest Science》2018,75(1):21
Key message
Stand density has a positive effect on C, K and Mg concentration in needle litterfall and a negative one on C, N, Ca, K, Mg, P, S, Zn, and Cu release from needle litter. Consequently, forest management practices such as thinning decrease nutrient concentration in needle litterfall and accelerate nutrient release from decomposing needles in Pinus halepensis plantations in Spain.Context
Silvicultural practices usually include stand density reduction resulting in changes in litterfall and litter decomposition rates. Little is known about the effect on nutrient concentrations in litterfall and nutrient release during decomposition even when this is the main path of nutrient return to soils.Aims
The aims of the study are to evaluate the seasonal pattern of nutrient concentration in litterfall, to study how nutrients are released from needle litterfall during decomposition, and to assess whether local basal area of the stand affects nutrient concentration of litterfall and nutrient release during litter decomposition.Methods
Eight plots were established on each of four stands covering the widest range in local basal area. A littertrap and 15 litterbags were placed on each plot. Periodically, needle litterfall and litter contained in the litterbags were analyzed for C, N, Ca, K, Mg, P, S, Fe, Cu, Mn, and Zn.Results
Local basal area had a positive effect on C, K, and Mg concentration in needle litterfall and a negative effect on the release of all the nutrients studied but Fe and Mn during the first 2 years of litter decomposition.Conclusion
Density management of stands has an impact on nutrient cycling, reducing nutrient concentration in needle litterfall, and accelerating nutrient release during decomposition.5.
Miguel Portillo-Estrada Janne F. J. Korhonen Mari Pihlatie Jukka Pumpanen Arnoud K. F. Frumau Lourdes Morillas Tiina Tosens Ülo Niinemets 《Annals of Forest Science》2013,70(4):367-379
? Context
The amount and chemistry of litterfall have been known to strongly vary among the years with important implications for ecosystem nutrient cycles, but there are few quantitative data describing such variations.? Aims
We studied the climatic implications on the variation in litterfall and its C and N input to soil in two distinct European coniferous forests.? Methods
Year-to-year variations in canopy litterfall were measured in a Scots pine stand (Hyytiälä, Finland) over 13 years, and a Douglas fir stand (Speulderbos, The Netherlands) over 3 years.? Results
Important inter-annual variations in litterfall were observed in Scots pine. Litterfall was mainly driven by leaf senescence; however, premature needle fall was observed in high wind speed and early frost events. The seasonal variation in litterfall was characterized by a maximum in September in Scots pine, and by a biphasic variation pattern in Douglas fir, in May and November. Lower seasonal variations and lower annual average in litterfall N content were observed in Scots pine.? Conclusion
Significant inter- and intra-annual variations in litterfall and chemistry and between the sites were demonstrated; and it depended on year-to-year differences in climate and extreme weather events. 相似文献6.
Patricia Valdespino Rigoberto Romualdo Laura Cadenazzi Julio Campo 《Annals of Forest Science》2009,66(1):107-107
7.
Aims
This study aims to evaluate the effects of wood ash application on nutrient dynamics and soil properties of an acidic forest soil (Arenosol).Methods
Treatments were loose and pelleted ash application (11?Mg?ha?1), alone or together with N fertiliser, and control treatment in a lysimeter experiment. Nutrient leaching was followed during a 2-year period and soil chemical and biological properties were evaluated at the end of the experiment.Results
Wood ash increased leaching of total N, NH 4 + -N, base cations and P, mainly during the first months, the effect being more pronounced for the loose formulation. At the end of the study period, a positive effect on soil nutrient availability and soil acidity reduction was seen. The application of loose and pelleted ash alone decreased N leaching and increased N microbial biomass at the end of the experiment. The C dynamics was weakly affected.Conclusion
Wood ash can be used to improve nutrient availability and balance nutrient exported by tree harvesting in acid forest soils, the effects at short-term being stronger for loose than for pelleted ash. However, their application should be carried out when vegetation is established to minimise nutrient losses at short-term and reduce the potential risk for water bodies. In N-limited soils, wood ash should be applied with N fertilisers to counteract N immobilisation. 相似文献8.
Context
Recruitment is an important process in forest stand dynamics, especially in uneven-aged stands. Continuous recruitment is a prerequisite for diverse, uneven-aged silvicultural systems, but patterns may vary significantly.Aims
The main goals of the study were to examine the recruitment of the main tree species in selection and irregular shelterwood stands in silver fir?CEuropean beech?CNorway spruce forests and to determine the main predictors of the recruitment occurrence.Methods
Data from 5,486 permanent inventory plots were used to study recruitment of saplings into the tree layer (diameter at breast height ??10?cm).Results
Recruitment rate differed significantly between selection (7.6?trees?ha?1?year?1) and irregular shelterwood (26.1?trees?ha?1?year?1) stands. Shade-tolerant fir and beech recruited with higher probability in selection stands, while light-dependent sycamore recruited with higher probability in irregular stands. In addition, forest types, soil pH, stand basal area, mean diameter, and the basal area of the same tree species with respect to recruitment were found to be important predictors of recruitment occurrence.Conclusions
The application of different uneven-aged silvicultural systems and their forms makes it possible to considerably influence the future tree species composition of uneven-aged forests. 相似文献9.
10.
11.
Suzanna Lettens Jos Van Orshoven Dominique Perrtn Bas Van Wesemael Bart Muys 《Annals of Forest Science》2008,65(6):604-604
12.
Context
The dipterocarp forests in the Central Highland of Vietnam are threatened by overharvesting. In addition, wildfires frequently affect their dynamics. Sustainable management of this unique forest type is of important concern.Aims
This study aims at providing a first set of operational information for forest management with a model-based approach. Specifically, we (a) evaluate selected cutting regimes with focus on maximum sustainable yield, (b) explore transformation times from a given to a desired forest state, and (c) preliminarily assess wildfire effects on yield.Methods
A size class model was developed as a tool to address these issues. Various diameter distributions defined by the q factor concept were used as possible desired equilibrium states to be assessed.Results
Maximum yields were estimated between 3.9 and 2.7?m3?ha?1?year?1, depending on site quality. Based on data from overharvested stands, time for reaching desired equilibria ranged between 20 and 60?years. In stands with frequent severe wildfires, the long-term yield may decrease by 40%.Conclusions
Our results suggest the model being an effective tool for simulating effects of treatment alternatives. We conclude that, despite a poor information basis, it is necessary to develop and refine such models for supporting sustainable forest management in Vietnam. 相似文献13.
? Context
The Kyoto Protocol allows the use of domestic forest carbon sequestration to offset emissions to a limited degree, while bioenergy as an unlimited emission reduction option receives substantial financial support in many countries.? Aim
The primary objective of this study was to analyze (1) whether these limits on forest carbon sequestration would be binding, thereby leading to inefficient mitigation, and (2) the total potential effect of the protocol on the greenhouse gas (GHG) fluxes in the forest sector.? Methods
A partial equilibrium model of the Norwegian forest sector was used to quantify the GHG fluxes in a base scenario with no climate policy, a Kyoto Protocol policy (KP policy), and a policy with no cap on forest carbon sequestration (FC policy), assuming that the policies apply the rest of the century.? Results
Carbon offsets are higher under the KP policy than in the base scenario and likewise higher than under the FC policy in the short run, but the KP policy fails to utilize the forest carbon sequestration potential in the long run as it provides considerably less incentives to invest in forestry than the FC policy.? Conclusion
The KP increases the Norwegian forest sector’s climate change mitigation compared to no climate policy but less in the long run than a carbon policy with no cap on forest carbon credits. 相似文献14.
Jiangming Mo Hua Fang Weixing Zhu Guoyi Zhou Xiankai Lu Yunting Fang 《Annals of Forest Science》2008,65(4):405-405
15.
Jean-Daniel Bontemps Pierre Gelhaye Gérard Nepveu Jean-Christophe Hervé 《Annals of Forest Science》2013,70(4):329-343
? Context
While historical increases in forest growth have been largely documented, investigations on historical wood density changes remain anecdotic. They suggest possible density decreases in softwoods and ring-porous hardwoods, but are lacking for diffuse-porous hardwoods.? Aims
To evaluate the historical change in mean ring density of common beech, in a regional context where a ring-porous hardwood and a softwood have been studied, and assess the additional effect of past historical increases in radial growth (+50 % over 100 years), resulting from the existence of a positive ring size–density relationship in broadleaved species.? Methods
Seventy-four trees in 28 stands were sampled in Northeastern France to accurately separate developmental stage and historical signals in ring attributes. First, the historical change in mean ring density at 1.30 m (X-ray microdensitometry) was estimated statistically, at constant developmental stage and ring width. The effect of past growth increases was then added to assess the net historical change in wood density.? Results
A progressive centennial decrease in mean ring density of ?55 kg?m?3 (?7.5 %) was identified (?10 % following the most recent decline). The centennial growth increase induced a maximum +25 kg?m?3 increase in mean ring density, whose net variation thus remained negative (?30 kg?m?3).? Conclusions
This finding of a moderate but significant decrease in wood density that exceeds the effect of the positive growth change extends earlier reports obtained on other wood patterns in a same regional context and elsewhere. Despite their origin not being understood, such decreases hence form an issue for forest carbon accounting. 相似文献16.
Jan Suszka Beata P. Plitta Marcin Michalak Barbara Bujarska-Borkowska Tadeusz Tylkowski Paweł Chmielarz 《Annals of Forest Science》2014,71(5):543-549
Context
Black poplar (Populus nigra L.) is an alluvial forest tree species whose genetic pool is decreasing in Europe. Poplar trees produce short-lived seeds that do not store well.Aim
The feasibility of seed storage in conventional and cryogenic conditions after their desiccation from water content (WC) of 0.15 to 0.07 g H2O g?1 dry mass (g g?1) was investigated.Methods
Seed germinability was evaluated (seeds with a radicle and green cotyledons were counted) after storage of seeds for a period of 3 to 24 months at different temperatures: 20°, 10°, 3°, ?3°, ?10°, ?20° or ?196°C.Results
Seeds desiccated to a 0.07 g g?1 WC can be stored successfully at ?10 °C and ?20 °C for at least 2 years. A significant decrease in germination was observed only after 12 months of seed storage (WC 0.15 g g?1) at temperatures above 0 °C. We demonstrated that both fresh (0.15 g g?1 WC) and desiccated (0.07 g g?1 WC) seeds can be preserved at ?196 °C for at least 2 years.Conclusions
Seed storage temperature and time of storage were statistically significant factors affecting seed storability. The presented data provide a foundation for the successful gene banking of P. nigra seeds. 相似文献17.
Humberto González-Rodríguez Roque Gonzalo Ramírez-Lozano Israel Cantú-Silva Marco Vinicio Gómez-Meza Eduardo Estrada-Castillón José Ramón Arévalo 《林业研究》2018,29(5):1307-1314
Studies on litterfall and decomposition provide estimations of decomposition rates of different ecosystems.This is key information to understanding ecosystem dynamics and changes in a scenario of global warming.The objective of this research was to assess litterfall production,the potential deposition of macro and micronutrients through leaf and twig fall as well as macronutrient—use efficiency in three forest ecosystems at different altitudes: a pine forest mixed with deciduous species(S1); a Quercus spp.forest(S2); and,a Tamaulipan thornscrub forest(S3).Total annual litterfall deposition was 594,742 and 533 g m~(-2) for S1,S2 and S3.Leaf litter was higher (68%) than twigs(18%),reproductive structures(8%) or miscellaneous material(6%).Micronutrient leaf deposition was higher for Fe followed by Mn,Zn and Cu.Macronutrient leaf deposition was higher for Ca followed by K,Mg and P.Even though P deposition in leaves and twigs was lower than other macronutrients,its nutrient use efficiency was higher than Ca,Mg or K.Altitude and species composition determine litter and nutrient deposition,with higher values at mid-altitudes(550 m).Altitude is an important factor to consider when analyzing litter production as well as nutrient deposition as shown in this study.Litter production and nutrient deposition are expected to change in a scenario of global warming. 相似文献
18.
Carbon storage in biomass,litter, and soil of different plantations in a semiarid temperate region of northwest China 总被引：1，自引：0，他引：1
? Context
A large area of abandoned land in the semiarid temperate region of China has been converted into plantations over the past decades. However, little information is available about the ecosystem C storage in different plantations.? Aim and methods
Our objective was to estimate the C storage in biomass, litter, and soil of four different plantations (monospecific stands of Larix gmelinii, Pinus tabuliformis, Picea crassifolia, and Populus simonii). Tree component biomass was estimated using allometric equations. The biomasses of understory vegetation and litter were determined by harvesting all the components. C fractions of plant, litter, and soil were measured.? Results
The ecosystem C storage were as follows: Picea crassifolia (469 t C/ha)?>?Larix gmelinii (375 t C/ha), Populus simonii (330 t C/ha)?>?Pinus tabuliformis (281 t C/ha) (P?<?0.05), 59.5–91.1 % of which was in the soil. The highest tree and understory C storage were found in the plantation of Pinus tabuliformis (247 t/ha) and Larix gmelinii (1.2 t/ha) respectively. The difference in tree C fraction was significant among tree components (P?<?0.05), following the order: leaf?>?branch?>?trunk?>?root. The highest soil C (SC) was stored in Picea crassifolia plantation (411 t C/ha), while Populus simonii plantation had a higher SC sequestration rate than others.? Conclusion
C storage and distribution varied among different plantation ecosystems. Coniferous forests had a higher live biomass and litter C storage. Broadleaf forests had considerable SC sequestration potential after 40 years establishment. 相似文献19.
Annabelle Amm Christian Pichot Philippe Dreyfus Hendrik Davi Bruno Fady 《Annals of Forest Science》2012,69(7):845-856
? Context
Dispersal and recruitment play a critical role in determining the abundance and the spatial structure of regeneration.? Aim
In this study, we estimated landscape scale seed dispersal using the inverse modeling method by fitting seedling counts to seed tree location and fertility in the European silver fir Abies alba Miller.? Methods
Seed trees and seedlings from three age cohorts were counted in 30 plots on Mont Ventoux (southeastern France) at elevations from 995 to 1,605?m, where the following ecological variables were measured: elevation, slope, aspect, light availability, and tree density. We developed and fitted a dispersal model, including a new parameter, recruitment rate, which depended both on the ecological characteristics of the plots and on seed production.? Results
Elevation was the factor that affected seedling recruitment the most, with an optimum value at around 1,200?m. Estimated A. alba seed dispersal distances were short (median values for the three cohorts, respectively, 16.4?C13.2?C19.6?m).? Discussion
We demonstrated that including the ecological characteristics of plots and post-dispersal recruitment processes realistically reduced estimates of seed dispersal distances which are otherwise grossly over-estimated using inverse modeling procedures. 相似文献20.
Peter Höller 《Annals of Forest Science》2014,71(1):81-89