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1.
Daniel Moreno-Fernández Fernando Montes Mariola Sánchez-González Francisco J. Gordo Isabel Cañellas 《European Journal of Forest Research》2018,137(1):17-27
The dynamics of mixed stands are more complex and less studied than those of monospecific stands. The objective of this work was to analyze the variables involved in seedling occurrence and seedling survival in mixed stands of Pinus pinaster and P. pinea in Mediterranean areas. From 2011 to 2016, regeneration of both species was monitored at two sites located in Central Spain. We installed 72 regeneration plots where seedling dynamics were monitored. All the trees in the study areas were measured and mapped. Additionally, we took hemispherical photographs in each regeneration plot. The average density of P. pinea seedlings over the study period was almost 20 times larger than that of P. pinaster. Our results indicate that the seedlings of both species grow under moderate light conditions. In addition, we found that the occurrence of seedlings of both species was related to the structure of the stand. P. pinea seedlings grew where the density and size of P. pinaster trees were low and where P. pinea trees provided moderately sheltered conditions, whereas the number of P. pinaster seedlings was related to under intermediate densities of P. pinaster trees. Furthermore, seedling survival was positively associated with age of the seedlings and negatively with the August average maximum temperature. The temporal continuity of mixed stands of P. pinea and P. pinaster in the study area is compromised by the observed lack of regeneration of P. pinaster. 相似文献
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3.
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.4.
Anna Hover Fabien Buissart Yves Caraglio Christine Heinz François Pailler Merlin Ramel Michel Vennetier Bernard Prévosto Sylvie Sabatier 《Annals of Forest Science》2017,74(2):39
Key message
The chronology of periods of organogenesis and elongation is highlighted in Pinus halepensis.The two first growth units of an annual shoot are preformed inside the bud during the previous year. The following growth units are formed during the spring or summer of the current year.Context
Analysis of annual shoot length growth phenology is crucial to assess the impact of climate change on tree production. Little is known about the basic growth characteristics and the phenology of pines.Aims
The present study disentangles the roles of shoot organogenesis vs elongation in the annual growth cycle of the polycyclic Aleppo pine.Methods
Growth of young Pinus halepensis trees was monitored monthly for 1 year. At each monitoring date, the bud content and meristem dimensions of the main stem shoots apices were analyzed.Results
The two first growth units of an annual shoot are preformed inside the bud during the previous year. The following growth units are formed during the spring or summer of the current year. The gap between a shoot organogenesis and its elongation may vary from 1 month, for the last growth unit, to half a year, for the first growth units.Conclusion
Our results underline the importance of taking seasonal environmental conditions from both the previous and the current year into account, in order to study the plasticity of annual shoot growth and its response to climate change and variability.5.
Francisco J. Baquedano Fernando Valladares Federico J. Castillo 《European Journal of Forest Research》2008,127(6):495-506
The Mediterranean evergreen woody plants Quercus coccifera and Pinus halepensis grow in a range of environments where selection by drought, heat and high irradiance can drive genetic and phenotypic differentiation
of populations. However, the role of these stresses in filtering out maladaptive genotypes remains unknown. We hypothesize
that this filtering is an important process for woody Mediterranean species due to their low phenotypic plasticity reported
in previous studies. We have studied the response of saplings of Q. coccifera and P. halepensis, originating from two contrasting populations (a rock outcrop and a garrigue formation), to water stress. Isozyme characterization
of genetic diversity was done to determine whether populations were genetically distinct. Water response analysis was based
on water relations, gas exchange, chlorophyll a fluorescence, pigment content, antioxidant status and morphological and structural parameters. Ecotypic differentiation was
found for both Q. coccifera and P. halepensis populations, with a higher population isozyme similarity and a higher frequency of dominance of a few genotypes at the rock
outcrop in both the species. P. halepensis exhibited small but significant differences between populations for plastic responses to water, with lower phenotypic plasticity
in saplings from the rock outcrop. Although it was not found in Q. coccifera, this pattern suggests that ecotypic differentiation rendering stress-tolerant ecotypes involves a decreased plasticity. Phenotypic
plasticity was not high but it explained over 75% of the total variability among individual plants. Thus, and although evidence
for ecotypic divergence was found in both the species, saplings were plastic enough to blur ecotypic differentiation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
There is a lack of knowledge to identify and classify forest structures according to the risk of crown fires, especially in
Mediterranean regions. In this study, for the first time, we use real information, obtained after a wildfire that burnt under
extreme meteorological conditions, to classify forest structures of Pinus halepensis into fuel types as a function of crown fire potential. We identified fourteen forest structures which characterize many forest
types in Western Mediterranean areas depending on canopy closure, number of tree layers, percent of each tree layer and overall
tree density. By using the pattern of fire types that burnt the most numerous forest structures, we have identified four fire
hazard groups of forest structures which are considered different fuel types. The first two had the lowest risk of active
crown fires and they differed in the proportion of surface fires and passive crown fires. The third fuel type was the threshold
between structures with low and high extreme fire behavior; while the fourth had a high risk of active crown fires. Firefighters
and forest managers who are demanding this kind of schema, will test and upgrade this classification of fuel types in function
of crown fire potential during future wildfires. 相似文献
7.
Agroforestry is a leading alternative for food security and forest conservation. A full understanding of positive and negative,
i.e. allelopathic, interactions between crops and forest trees is necessary for producing crops and conserving forests especially
within the threatened Mediterranean forest ecosystems. The present study explored the allelopathic effects of green and senescent
leaf and soil extracts of two agroforestry trees—Pinus halepensis and Quercus coccifera—on the germination of wheat, barley, lentil, chickpea, and fababean as the major grain crops of Jordan. Results revealed
that allelopathic effects reduced seed germination of these crops. Germination reduction reached a maximum of 75% in fababean
treated with green extracts of Q. coccifera and differed among crops and extract sources, but not between tree species. Comparing between green and senescent leaf and
soil extract, regarding their effect on germination percentage, it was noticed that these effects were similar in some crops
and were different in others. Germination responses were generally different between cereals and legumes where cereals tend
to be less affected by allelopathic influences than legumes, especially fababean. We suggest using cereals such as wheat and
barley in agroforestry practices in the Mediterranean region of Jordan. 相似文献
8.
Inoculation with edible fungi bestows an added value on mycorrhized plants since production of mushrooms as a secondary crop
can be an economically-valuable resource in forestry management. In order to establish a protocol for controlled mycorrhization
of Pinus halepensis with the edible fungus Lactarius deliciosus, several factors such as fertilisation (35, 60 or 120 mg total N and 13.5, 27 or 54 mg total P), potting substrate (sphagnum
peat or sphagnum peat/vermiculite) and fungal inoculum (mycelial slurry produced in a bioreactor, alginate beads or peat/vermiculite)
were assessed. The most effective inoculum was mycelial slurry at a dose of 10 ml/plant. The two potting substrates assessed
were compatible with mycorrhiza formation. The greatest number of mycorrhized seedlings was obtained with a moderate level
of N (35 mg/plant) or P fertilisation (27 mg/plant). Inoculation did not produce a consistent growth effect on P. halepensis, but seedlings met the quality requirements, making them suitable for planting out. 相似文献
9.
Teresa Bueis María Belén Turrión Felipe Bravo Valentín Pando Adele Muscolo 《Annals of Forest Science》2018,75(1):34
Key message
Water availability and soil pH seem to be major constraints for enzyme activities in calcareous soils under Pinus halepensis and acidic soils under Pinus sylvestris plantations respectively. Proposals for improving enzyme activities may include the promotion of broadleaf species to increase soil pH and the modulation of stand density or the implementation of soil preparation techniques to facilitate water infiltration.Context
Soil enzymes play a key role in nutrient turnover in forest ecosystems, as they are responsible for the transformation of organic matter into available nutrients for plants. Enzyme activities are commonly influenced by temperature, humidity, nutrient availability, pH, and organic matter content.Aims
To assess the differences between enzyme activities in calcareous soils below Pinus halepensis and acidic soils below Pinus sylvestris plantations in Spain and to trace those differences back to edapho-climatic parameters to answer the questions: Which environmental factors drive enzyme activities in these soils? How can forest management improve them?Methods
The differences in climatic, soil physical, chemical, and biochemical parameters and the correlations between these parameters and enzyme activities in soils were assessed.Results
Low pH and high level of phenols in acidic soils under Pinus sylvestris and water deficit in calcareous soils under Pinus halepensis plantations appeared to be the most limiting factors for enzyme activities.Conclusion
Options such as the promotion of native broadleaf species in the Pinus sylvestris stands and the modulation of Pinus halepensis stand density or the implementation of soil preparation techniques may improve enzyme activities and, therefore, nutrient availability.10.
José Ramón González-Olabarria Jordi Garcia-Gonzalo Blas Mola-Yudego Timo Pukkala 《Annals of Forest Science》2017,74(3):52
Key message
We generate flexible management rules for black pine stands, adaptable to alternative stand management situations and entailing thinnings, final-felling, and salvage cuts, based on the results on 270 stand level optimizations.Context
Forest management instructions often rely on the anticipated prediction of the stand development, which poses a challenge on variable economic and environmental conditions. Instead, an alternative approach to better adapt forest management decisions to changing conditions is defining flexible rules based on thresholds that trigger management operations.Aims
This article develops rules for the adaptive management of P. nigra stands in Catalonia (Spain) addressing the risk of fire and post-fire forest management.Methods
The stochastic version of the simulation-optimization system RODAL was used to optimize the management of forest stands in three sites under different fire probability levels. A total of 270 optimizations were done varying site fertility, fire probability, and economic factors. The results of the optimizations were used as the basis of flexible forest management rules for adaptive stand management.Results
The developed management rules defined the basal area limit for thinning, the thinning intensity, the mean tree diameter at which regeneration cuttings should start, and the basal area below which a salvage cutting should be done. Fire risk was not a significant predictor of the models for thinning and final cutting rules.Conclusion
The presented rules provide a flexible tool for forest management during the stand development and under changing conditions when the management objective is to maximize economic profitability of timber production.11.
• Introduction
Laricio pine (Pinus nigra J.F. Arn. ssp. laricio (Poiret) Maire var Corsicana Hyl.) is a form of black pine endemic to Corsica, that may now be under threat due to current fire regimes and competition with maritime pine (Pinus pinaster Aiton). 相似文献12.
Pilar Mañas Elena Castro Pau Vila Jorge de las Heras 《European Journal of Forest Research》2010,129(4):521-530
Peat moss is gradually being replaced by other materials as a growing medium in forest nurseries due to economic and ecological
constraints. In this study, six different mixtures were tested, mixing peat moss (P) and pine bark (B) with digested sewage
sludge (S) activated sewage sludge (A) and paper mill sludge (M), as growing media for Pinus halepensis seedlings; three different waste doses were applied. Seed germination percentage, seedling growth and foliar nutrient content
after 1 year in a greenhouse and percentage survival after transplanting were recorded. The influence of base substrate (P
or B) on germination percentage changed in different ways according the type of waste. The order of the different applied
mixtures by suitability (germination rate and seedling growth) from best to worst was as follows: activated sludge with peat,
activated sludge with pine bark, sewage sludge with peat, sewage sludge with pine bark, paper mill sludge with pine bark and
finally paper mill sludge with peat. 相似文献
13.
Fertility variation and effective number of parents were estimated in the 100 individuals from each of three plantation populations (P1, P2 and P3) of the endangered Pinus nigra. subsp. pallasiana var. pyramidata established in the Isparta–Golcuk district in southern Turkey in 1990. Potential relations between cone yield and growth characters (height, diameter at breast height, diameter at base and crown diameter) were also investigated. Large differences were found among populations and within populations for cone production and growth characters. Mean cone production was eight (ranging from 6.5 in P2 to 9.1 in P1) for the three populations. The 10 most productive individuals for cones produced 32% of the total cones in P1, 39% in P2 and 34% in P3; 21, 16 and 6 individuals, respectively did not produce any cones in the populations. According to the correlation analyses, the relation between cone yield and growth characters changed for the populations, while height, diameter at breast height and crown diameter were positively significantly correlated (r = 0.182, 0.135 and 0.209; p ≤ 0.05) with cone production for the three populations. Fertility variation was 1.81 in total of three populations, ranging from 1.72 in P3 to 3.45 in P1). Effective number of parents was 142 (55.2 of number of parents censused; 29%, P1; 49.8%, P2; 58.3%, P3). 相似文献
14.
Nutrient retranslocation in trees is important in nutrient budgets and energy flows in forest ecosystems. We investigated nutrient retranslocation in the fine roots of a Manchurian Ash (Fraxinus mandshurica) and a Larch (Larix olgensis) plantation in northeastern China. Nutrient retranslocation in the fine roots was investigated using three methods, specifically, nutrient concentration, the ratio of Ca to other elements (Ca/other elements ratio) and nutrient content. The method based on nutrient content proved most suitable when investigating nutrient retranslocation from fine roots of the two species. The nutrient-content-based method showed that there were retranslocations of N, P, K and Mg from the fine roots of Manchurian Ash, with retranslocation efficiencies of 13, 25, 65, and 38 %, respectively, whereas there were no Ca retranslocations. There were retranslocations of N, P, K, Ca and Mg from the fine roots of Larch, with retranslocation efficiencies of 31, 40, 52, 23 and 25 %, respectively. 相似文献
15.
The problem of salinized soils has become one of the most serious constraints to agricultural and forest productivity. With the purpose of enhancing salt stress tolerance of Populus tomentosa, we transformed this tree species with spermidine synthase (SPDS) genes derived from an apple by an Agrobacterium-mediated method. Four transgenic clones were confu'med by PCR and Southern blot analysis. As well, the expression of introduced SPDS genes was analyzed by real-time quantitative PCR. 相似文献
16.
Pinus densiflora f.umbraculifera, commonly known as utsukushimatsu, is a distinctively shaped form of Japanese red pine whose growth is restricted to a forest
stand in Shiga Prefecture, Japan. The inheritance mode of morphological characteristics of utsukushimatsu was studied to preserve
the genetic resource of this pine. As previously reported, F1 trees grown from open-pollinated seeds harvested from trees inhabiting the native stand showed two phenotypes: one resembling
utsukushimatsu, which produces multiple trunks, and the other resembling normalP. densiflora, which produces one or a few trunks. In the present study, controlled pollination was carried out using F1 and normalP. densiflora trees. Segregation ratios of the two phenotypes observed in the F2 population showed that the morphological characteristics of utsukushimatsu are inherited recessively. This suggests that
the mutation of one gene or a few closely linked genes controls the morphological characteristics of utsukushimatsu. Since
multiple trunk formation of utsukushimatsu might be related to a loss of lateral bud inhibition, it follows that a simple
gene mutation breaks apical dominance inP. densiflora. 相似文献
17.
Spatial pattern of recruitment is an important factor influencing population dynamics of plant communities. The spatial pattern is determined by seed dispersal and by the spatial variability of germination and initial survival. In the process of forest expansion following farmland abandonment, mid- and late-successional species are often dispersed in pioneer forests by birds. This could result in an aggregated spatial pattern of seeds that could influence the dynamics of these species in mixed pioneer forests. In the sub-Mediterranean area, mid- and late-successional species such as Quercus pubescens (downy oak) and Fagus sylvatica (European beech) are expected to replace pioneer Pinus species. Using a point sampling method we demonstrated that beech and oak seedlings (height <2 m) have a clumped distribution in the understorey of pine. This could result from an aggregated dispersal by jays (dispersal effect) or from preferential recruitment in particular habitats (habitat effect). To test these hypotheses we proposed a statistical analysis of spatial patterns of regeneration of beech and oak. Ground cover variables (i.e. cover by rock outcrops, herbs, box shrubs, mosses or pine) did not differ significantly around seedlings as compared with random sample plots. Likewise, clumped seedlings had growth similar to isolated seedlings, thus refuting the hypothesis of preferential location in the most favourable microsites. Aggregated dispersal seems to be involved in the process of regeneration. Since beech and oak seedlings have contrasting ecological demands, we discuss the implication of this pattern for the replacement dynamics of pine by these species. 相似文献
18.
Barbara Moser Christoph Bachofen Jonathan D. Müller Marek Metslaid Thomas Wohlgemuth 《Annals of Forest Science》2016,73(4):959-970
Key message
Pinus sylvestris seedlings quickly expand their roots to deeper soil layers while Pseudotsuga menziesii concentrates its root system in the topsoil, thereby running the risk of desiccation during long dry spells, as indicated by lower survival after simulated summer drought.Context
Pseudotsuga menziesii (Douglas-fir) is regarded as a promising species to maintain the productivity of Central European lowland forests given the projected increase of long dry spells.Aims
Will the species be able to regenerate from seed and spread outside plantations in a drier temperate Europe?Methods
We measured the relative growth rate, biomass allocation, root architecture, and phenotypic plasticity of Pseudotsuga menziesii seedlings sown in a common garden and grown under current precipitation and prolonged drought, respectively. The species’ competitive ability with respect to Pinus sylvestris L., the most drought-tolerant native conifer in Central Europe, was assessed during three growing seasons.Results
Pinus sylvestris seedlings had higher relative growth rates than did Pseudotsuga menziesii seedlings, first in terms of aboveground biomass and later in terms of shoot height. This resulted in heavier and taller seedlings after three growing seasons under both moist and dry conditions. Shorter vertical roots corresponded with lower survival of Pseudotsuga menziesii seedlings under dry conditions.Conclusion
Fast root proliferation allows Pinus sylvestris seedlings to reach deeper water pools that are less rapidly depleted during transient drought. By contrast, the shallow root system might put Pseudotsuga menziesii seedlings at the risk of desiccation during prolonged dry spells.19.
Natsumi Kanzaki Takuya Aikawa Noritoshi Maehara Yu Ichihara 《Journal of Forest Research》2011,16(4):325-330
The pinewood nematode (PWN) Bursaphelenchus xylophilus is an invasive pathogen that was introduced from North America to Asian countries and Portugal and is devastating native
pine forests. Some native European and Asian Bursaphelenchus nematodes also have weak to moderate pathogenicity to native pine species. To evaluate the potential risk of native Bursaphelenchus species, we inoculated ten Japanese Bursaphelenchus species into native pine species (the dominant forest species) in Japan, and evaluated their pathogenicity using mortality
and tracheal tissue damage as indices. Inoculation was conducted on August 3, 2007, and the symptoms were observed every 2 weeks
until February 1, 2008. None of the inoculated trees, excluding the pathogenic PWN inoculated control, showed external disease
symptoms; however, four species [a less pathogenic PWN isolate, B. luxuriosae, Bursaphelenchus sp. NK215 (undescribed), and NK224 (undescribed)] caused tracheal tissue damage in inoculated seedlings and showed weak pathogenicity.
Therefore, we conclude that there are some potentially pathogenic native species of nematodes distributed in Japan. Interestingly,
two of these weakly pathogenic species, B. luxuriosae and NK215, are not associated with Pinaceae trees, suggesting that nematode pathogenicity may be a pre-adaptive character.
More experimental studies under different conditions are necessary to accurately evaluate the potential risk of these pathogens. 相似文献
20.
Akram Taghizadeh Saroukolai Saeid Moharramipour Mohammad Hadi Meshkatalsadat 《Journal of pest science》2010,83(1):3-8
Red flour beetle Tribolium castaneum (Herbst) and rice weevil Sitophilus oryzae (L.) are considered to be the major insect pests in storage. Essential oils from aromatic plants are recognized as proper
alternatives to fumigants. Thymus persicus (Ronniger ex Rech. f.) is one of these plants that have medicinal properties and is indigenous to Iran. The essential oil
was obtained from aerial parts of the plant and analyzed by GC and GC–MS. Carvacrol (44.69%) and thymol (11.05%) were the
major constituents of the oil extracted. In this experiment, fumigant toxicity of the essential oil was studied against T. castaneum, S. oryzae at 27 ± 1°C and 60 ± 5% RH in dark condition. The adult insects were exposed to the concentrations of 51.9, 111.1, 207.4
and 370.4 μl/l air to estimate median lethal time (LT50) values. The fumigant toxicity was increased in response to increased essential oil concentrations. The LT50 values at the lowest and the highest concentrations tested were ranged from 28.09 to 13.47 h for T. castaneum, and 3.86 to 2.30 h for S. oryzae. It was found that S. oryzae adults were much more susceptible to the oil than T. castaneum. After 24 h of exposure, the LC50 values (95% fiducial limit) for T. castaneum and S. oryzae were estimated to be 236.9 (186.27–292.81) and 3.34 (2.62–4.28) μl/l air, respectively. These results suggest that T. persicus essential oil merits further study as potential fumigant for the management of these stored-product insects. 相似文献