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1.
• Introduction
The annual development cycle of boreal and temperate trees results from an evolutionary trade-off between two opposing forces. These are namely, the adjustment of leaf phenology to the timing of frost occurrence at the beginning and/or the end of the growth season countered by an effective adjustment to the duration of the growth season to maximise photosynthesis and biomass production during the growing season. 相似文献2.
Grégoire Vincent Jean-François Molino Lucile Marescot Karim Barkaoui Daniel Sabatier Vincent Freycon Jean Baptiste Roelens 《Annals of Forest Science》2011,68(2):357-370
• Introduction
Various processes contribute to shaping the local assemblage of species in hyperdiverse tropical forest. The relative contribution of environmental factors and dispersal limitation in determining the spatial distribution of saplings at local scale is unclear. 相似文献3.
Fall fertilization of Holm oak affects N and P dynamics,root growth potential,and post-planting phenology and growth 总被引:2,自引:0,他引:2
Juan A. Oliet José M. Salazar Rafael Villar Eduardo Robredo Fernando Valladares 《Annals of Forest Science》2011,68(3):647-656
• Introduction
For Holm oak (Quercus ilex L.), a flush growing species, nutrient loading during the growing season is difficult and can lead to a low nutrient status of the seedlings. To provide insights about Holm oak nutrient dynamics during fall in the nursery and subsequent planting performance, a factorial nursery experiment was conducted in a mild fall–winter area testing the effects of timing of fertilization (early and late fall) and rate (two doses of a NPK fertilizer that applied 28 and 56 mg N per seedling), followed by an experimental plantation. 相似文献4.
Victoria González-Rodríguez Rafael Villar Raquel Casado Elena Suárez-Bonnet José Luis Quero Rafael M. Navarro-Cerrillo 《Annals of Forest Science》2011,68(7):1217-1232
Introduction
The great spatial and temporal heterogeneity of Mediterranean ecosystems can influence establishment success in woody species, whose natural regeneration occurs to a very small extent. In this work, the effect of the spatial pattern of environmental variables (light availability, soil moisture and herbaceous production) on seedling emergence, growth, survival and establishment success was examined by using a spatially explicit approach. 相似文献5.
6.
Mélanie Saulnier Jean-Louis Edouard Christophe Corona Frédéric Guibal 《Annals of Forest Science》2011,68(1):189-200
•Introduction
In the context of climate change, assessing climate–growth relationships is of high importance in order to understand how forest ecosystems evolve and to test climate models at regional scale. 相似文献7.
Katri Luostarinen 《Annals of Forest Science》2011,68(5):985-992
Introduction
As the major resources of Siberian larch planted in Finland will be at a harvestable age in the near future, knowledge concerning wood and fibre properties of cultivated larches is needed. The properties affect both the character of pulp and paper, as well as properties important in the structural usage. 相似文献8.
Integrating regional climate change into allometric equations for estimating tree aboveground biomass of Masson pine in China 总被引:1,自引:0,他引:1
Liyong Fu Xiangdong Lei Zongda Hu Weisheng Zeng Shouzheng Tang Peter Marshall Lin Cao Xinyu Song Li Yu Jingjing Liang 《Annals of Forest Science》2017,74(2):42
Key message
A climate-sensitive aboveground biomass (AGB) equation, in combination with nonlinear mixed-effects modeling and dummy variable approach, was developed to examine how climate change may affect the allometric relationships between tree diameter and biomass. We showed that such changes in allometry need to be taken into account for estimating tree AGB in Masson pine.Context
As a native species and being widely distributed in subtropical China, Masson pine (Pinus massoniana Lamb.) forests play a pivotal role in maintaining forest ecosystem functions and mitigation of carbon concentration increase at the atmosphere. Traditional biomass allometric equations do not account for a potential effect of climate on the diameter–biomass relationships. The amplitude of such an effect remains poorly documented.Aims
We presented a novel method for detecting the long-term (2041–2080) effects of climate change on the diameter–biomass relationships and the potential consequences for long-term changes of biomass accumulation for Masson pine.Methods
Our approach was based on a climate-sensitive AGB model developed using a combined nonlinear mixed-effects model and dummy variable approach. Various climate-related variables were evaluated for their contributions to model improvement. Heteroscedasticity was accounted for by three residual variance functions: exponential function, power function, and constant plus function.Results
The results showed that diameter at breast height, together with the long-term average of growing season temperature, total growing season precipitation, mean temperature of wettest quarter, and precipitation of wettest quarter, had significant effects on values of AGB. Excessive rain during the growing season and high mean temperature in the wettest quarter reduced the AGB, while a warm growing season and abundant precipitation in the wettest quarter increased the AGB.Conclusion
Climate change significantly affected the allometric scale of biomass equation. The new climate-sensitive allometric model developed in this study may improve biomass predictions compared with the traditional model without climate effects. Our findings suggested that the AGB of Masson pine trees with the same diameter at breast height under three climate scenarios including representative concentration pathway (RCP) 2.6, RCP 4.5, and RCP 8.5 in the future period 2041–2080 would increase by 24.8 ± 32.7% (mean ± standard deviation), 27.0 ± 33.4%, and 27.7 ± 33.8% compared with the constant climate (1950–2000), respectively. As a consequence, we may expect a significant regional variability and uncertainty in biomass estimates under climate change.9.
Feng Chen Yu-jiang Yuan Wen-shou Wei Zi-ang Fan Tong-wen Zhang Hua-ming Shang Rui-bo Zhang Shu-long Yu Chun-rong Ji Li Qin 《Annals of Forest Science》2012,69(6):723-733
? Introduction
Siberian larch (Larix sibirica) is a highly climate sensitive species. Presently, the Altay Mountains is covered by widespread forests dominated by Siberian larch and thus has a great potential for dendroclimatological studies. However, tree-ring network of the Altay Mountains has not yet been well developed. The development of the new chronologies and the knowledge about the influence of climatic variables on tree growth is needed.? Method
X-ray densitometric techniques were applied to obtain ring width (RW) and maximum latewood density (MXD) of Siberian larch from two upper tree line sites in the Altay Mountains, China. Climatic responses in ring widths and maximum latewood densities from the Altay Mountains (China, Russia, and Mongolia) were investigated by simple correlation analyses. To assess the common growth forces among the individual sites of the Altay Mountains, simple correlation, principal component analyses, and spatial correlation analysis were applied over the common period of the chronologies.? Results
Ring width and maximum latewood density increases with decreasing precipitation, increasing temperature from late spring to late summer during the growing season. Based on the results of principal component analyses and spatial correlation analysis, summer temperature (June?CJuly) is the most important forces on the Siberian larch growth of the Altay Mountains. The growth of Siberian larch in the Altay Mountains captures the current warming trend. The growth of Siberian larch did not clearly lose its sensitivity under most recent warming in our study areas.? Conclusions
The new MXD chronologies is presently the longest, absolutely dated, tree-ring density record yet developed from China. The climate response analysis shows that the RW and MXD of Siberian larch have strong responses to temperature in the growing season. Thus, MXD and RW of Siberian larch provides the best information for climate reconstruction in the warm season. Tree-rings of Siberian larch allow detecting the recently observed warming trend and putting it into the long-term climatic context in the Altay Mountains, due to the strong growth sensitivity to temperature change. 相似文献10.
11.
Context
The European black poplar (Populus nigra) is considered one of the most seriously endangered indigenous tree species. However, the total area covered by monoclonal plantations of hybrid poplar is growing, because of the high profitability of these trees. 相似文献12.
• Introduction
Fargesia qinlingensis is the primary food source for the endangered giant panda during the summer months in the Qinling Mountains, but little is known about its spatial distribution and plant community associations. 相似文献13.
Eitaro Fukatsu Yuichiro Hiraoka Noritsugu Kuramoto Hiroo Yamada Makoto Takahashi 《Annals of Forest Science》2018,75(4):96
Key message
Accurate evaluation of genetic performances of trees is crucial in order to improve the efficiency of forest tree breeding. We revealed that spatial analysis is effective for predicting individual tree breeding values at the forward selection stage of Cryptomeria japonica D. Don (sugi) breeding program by using a novel validation approach.Context
In the process of selecting genetically superior trees for breeding, appropriate handling of environmental effects is important in order to precisely evaluate candidate trees. Spatial analysis has been an effective statistical approach for genetic evaluation at sites with heterogeneous microenvironments. However, the efficiency of spatial analysis on forward selection has not been validated on a practical scale to date.Aims
This study aimed to reveal the effectiveness of spatial analysis, which incorporates spatially autocorrelated residuals into mixed models, for the prediction of breeding values at the forward selection stage by validation using progeny or clonal tests of forward-selected individuals.Methods
Tree height was analyzed by ordinary randomized complete block design models and spatial models incorporating spatially autocorrelated residuals in a linear mixed model framework, and model selection was conducted at thirty Cryptomeria japonica D. Don breeding population sites having various topographical ruggedness. For validation, three clonal tests and one progeny test of individuals selected from three and four breeding populations, respectively, were used. The effectiveness of forward selection using the two models was evaluated based on the correlation between individual breeding values at the stage of forward selection and genotypic and breeding values that were estimated by clonal and progeny tests.Results
Spatial models were more predictive than ordinary models in all cases. Spatial correlation parameters tend to increase with the topographical ruggedness index of each site. The correlation coefficients between breeding values at the time of forward selection and genotypic or breeding values evaluated in succeeding clonal and progeny tests were significantly higher in spatial models than in ordinary models in six out of nine cases.Conclusion
Validation using progeny and clonal tests of forward-selected individual trees revealed that spatial analysis is more effective for the evaluation of genetic performance of individuals at the stage of forward selection in Cryptomeria japonica.14.
Noel Houédougbé Fonton Gilbert Atindogbe Norbert M. Hounkonnou Raoul Odjo Dohou 《Annals of Forest Science》2011,68(8):1315-1321
Introduction
Over the past decades, savannah woodland management in the Sudanian region of Africa has focused on rotation and enrichment. To best manage these resources, it is critical to first understand the ecological processes influencing the behaviour of plants in their habitats. Previous work on the spatial patterns of trees has failed to account for the effects of plot size. 相似文献15.
• Context
Forest stand dynamics models simulate the growth of trees in stands; based on field measurements and system knowledge, they provide a relatively precise representation of forest growth and are well adapted for forest management purposes. Architectural models describe the structure of plants according to ontogenetic development processes; as a support of biomass production and partitioning at organ scale, they simulate individual tree development. 相似文献16.
François Pimont Jean-Luc Dupuy Rodman R. Linn Sylvain Dupont 《Annals of Forest Science》2011,68(3):523-530
Introduction
Forest fuel management in the context of fire prevention generally induces heterogeneous spatial patterns of vegetation. However, the impact of the canopy structure on both wind flows and fire behavior is not well understood. 相似文献17.
• Context
Landscape structure is crucial for forest conservation in regions where the natural forest is fragmented. Practical conservation is currently shifting from local stands to a landscape perspective, although few studies have tested the relative effects of different spatial scales on plant species composition and diversity in forests. 相似文献18.
Key message
Bark thickness was shown to vary between regions, stands, and trees. Bark thickness prediction equations of different model complexity can be suggested depending on the purpose of application. Site and stand conditions, which influence variation of growth rate to a large extent, seem to have a strong influence on bark thickness, with better site quality leading to smaller relative bark thickness.Context
For many applications in forestry and forest science, local or regional species-specific bark thickness equations are used to estimate inside-bark diameters with outside-bark diameter measurements.Aims
The objectives of this study were (1) to assess variation in bark thickness due to tree and stand factors in two Norway spruce (Picea abies (L.) Karst) datasets from different time periods, (2) to compare and evaluate alternative established model forms for estimating bark thickness, and (3) to assess spatial variation in bark thickness to estimate the effects of environmental factors on bark thickness.Methods
Different bark thickness models were chosen from the literature and compared for their predictive quality for new measurements and a dataset from the 1970s. Mixed-effect modelling was applied to account for the hierarchical data structure, and generalized additive mixed models were used to analyse spatial effects and the influence of climatic factors, such as precipitation and temperature.Results
A strong positional autocorrelation of bark thickness within trees and within plots could be shown. Bark thickness was smaller in the new data compared to the measurements from the 1970s. The variation between stands could not be explained by the tested environmental factors, but tree age had a strong positive effect on bark thickness.Conclusion
In the study region, the variation of site productivity and individual growth rate seem to have a strong influence on bark thickness, whereas no significant effect of large scale climatic factors could be found.19.
? Context
The effects of leaf inclination on plant light capture, growth, and water balance of monospecific canopies are well documented, but we still lack information on such effects in the case of multispecific canopies.? Aims
We investigated the effects of leaf inclination on the absorption of photosynthetically active radiation (PAR) of a mixed forest.? Methods
We ran a 3D mechanistic radiation transfer model for a Mediterranean forest where Pinus halepensis makes the upper strata while Quercus ilex occupies the lower strata. As factors, we included (1) the distributions of leaf inclinations that ranged from vertical to horizontal (including the actual inclinations), (2) the fraction of diffuse light, sun position, and leaf area index (LAI), and (3) the Pinus/Quercus LAI ratio.? Results
Simulated PAR absorption was more than twice as sensitive to leaf inclination in oaks than in pines because oaks depended on PAR transmitted below the pine layer. The extent of the effect depended on season, fraction of diffuse light, LAI, and vegetation spatial structure. None of the observed inclinations maximized PAR absorption, suggesting a trade-off with water economy.? Conclusion
Erroneous assumptions about leaf inclination lead to larger errors when modelling heterogeneous, mixed canopies. This also highlights potential caveats when using models that do not account for the spatial structure of canopies. 相似文献20.
Marieke van der Maaten-Theunissen Hans-Peter Kahle Ernst van der Maaten 《Annals of Forest Science》2013,70(2):185-193