Pinus Pinaster Plantation Research Articles

Group selection cutting for regenerating Mediterranean Pinus pinaster plantations: Gap effects on seedling survival

Diversification of forests, both in terms of structure and species, has been identified as one of the main strategies for adapting forests to climate change. Among the different options available for managers to promote diversification, regeneration cuttings are a suitable option to meet these objectives in adult stands close to rotation ages. The regeneration of maritime pine (Pinus pinaster Ait.) stands is a major issue throughout its distribution area, with summer survival being the main bottleneck for seedling establishment and development. Group selection cutting system may be the best option to promote uneven-aged and mixed structures in shade intolerant species, such as maritime pine. Gaps generate different regeneration niches for species of contrasting shade tolerance while creating uneven-aged stands, which are potentially more resilient to the impacts of climate change.In our experiment, gaps of two different sizes (1.5 and 2.5 times the dominant height of the stand, both sizes being smaller than those proposed in literature) were opened up to test the effects on natural regeneration success in a planted 53-year-old maritime pine stand in Central Spain. There were nine gaps of each size, along with nine control plots, containing 1-m radius subplots distributed within them to record natural regeneration of maritime pine and other species, in addition to several ecological factors and seedling characteristics. A survival model was fitted to highlight the main factors driving seedling survival. Gaps were found to have a significant positive effect on seedling survival, as well as mid-shade positions within the gaps and the age of the seedlings. Summer was found to have a negative effect on seedling survival. No effect of inter-species competition (scrub or herbs), litter coverage or geomorphological characteristics (slope, aspect or altitude) was found. Our results indicate, therefore, that group selection system cuttings, even with small gap sizes (1.5 and 2.5 times the dominant height), would provide a suitable method for the regeneration of Mediterranean maritime pine plantations.

The use of portable winch for forest harvesting operations in Pinus pinaster plantation areas

Ülke nüfusunun artışına paralel olarak odun üretim miktarlarında da son yıllarda önemli artışlar görülmektedir. Odun üretim miktarlarında ortaya çıkan bu artış üretim çalışmalarında da yeniliklere gitmeyi zorunlu kılmaktadır. Özellikle odun üretim çalışmalarında taşınabilir ve düşük maliyetli yeni teknolojilerin ve makinelerin kullanımı önemli bir durum almıştır. Bu makineler arasında el vinçleri son yıllarda ülkemizde ve dünya ormancılık çalışmalarında da kullanılmaya başlanmıştır. Bu vinçler kurulum ve sökülmesi yanında kullanım açısından da çok kullanışlı makinelerdir. Bu çalışmada, İstanbul Orman Bölge Müdürlüğü’ne bağlı Sarıyer Orman İşletme Şefliği sınırları içerisinde yer alan Sahilçamı plantasyon sahalarında el vincinin kullanımı incelenmiştir. Çalışmalar sonucunda el vincinin ortalama 50 metrelik sürütme mesafesinde saatlik verimi 1.10 m3/sa ve günlük verimi 8.80 m3/gün olarak bulunmuştur. El vincinin saatlik yakıt tüketimi ise 1.4 lt/sa olarak belirlenmiştir.

Contrasting patterns of lichen abundance and diversity in Eucalyptus globulus and Pinus pinaster plantations with tree age

We explore the patterns of epiphytic lichen community richness and composition (both taxonomical and functional) on the trunks of the two most important species used for forestry in NW Spain (the non-native Eucalyptus globulus, and Pinus pinaster, a native species in the Iberian Peninsula) across a chronosequence of age classes. We recorded a total of 56 lichen taxa in 30 genera across all sites. Lichen abundance and species richness was significantly affected by tree species (eucalypt vs. pine plantations) by age and by the interaction between them. Pines had more lichen abundance and diversity than eucalypts in all ages, with 2–17 times more lichen cover and 2.5–6.5 times higher average species richness, depending on the age. The taxonomical and functional composition of the epiphytic community was also affected by the tree species, the age and its interaction. The colonization pattern in both eucalypts and pines was typical of an additive system, with an ongoing increase of species and epiphytic cover, where early colonizers persist and new species are added later on without replacing the existing species. This study demonstrates that plantations of the native species P. pinaster provides a more suitable habitat for lichens than those of the exotic E. globulus in the study region, not only as a consequence of longer rotation cycles but for the higher rate of lichen colonization and expansion in their trunks, as these differences were observed in all ages.

Resilience or Vulnerability of the Rear-Edge Distributions of Pinus halepensis and Pinus pinaster Plantations Versus that of Natural Populations, under Climate-Change Scenarios

Abstract It is predicted that changes in climate will lead to episodes of large forest decline and mortality. Therefore, the distributions of forest plantations and natural stands might already be facing such impacts. We selected the most arid zone of south-eastern Europe (eastern Andalusia) to assess how the distributions of Pinus halepensis Miller. and Pinus pinaster Aiton forest plantations and natural stands cope with climate change and to determine whether natural or planted distributions would be more stable under future climate-change scenarios. We used presence-point locations from natural distributions, obtained from the third Spanish National Forest Inventory, to develop ensemble species distribution models. The forecast predicted a slight increase in the potential distribution of both species by 2040, with a subsequent drastic decrease until 2099. Pinus halepensis had larger current and future potential distributions than P. pinaster but a slightly greater decrease with time in the potential distribution than that of P. pinaster. On the other hand, the natural and planted distributions of P. halepensis were more vulnerable to future climate change scenarios than those of P. pinaster. Natural populations will likely be more resilient to climate change than planted populations.

Integration of a Landsat Time-Series of NBR and Hydrological Modeling to Assess Pinus Pinaster Aiton. Forest Defoliation in South-Eastern Spain

Climate change is increasing the vulnerability of Mediterranean coniferous plantations. Here, we integrate a Landsat time series with a physically-based distributed hydrological model (Watershed Integrated Management in Mediterranean Environments—WiMMed) to examine spatially-explicit relationships between the mortality processes of Pinus pinaster plantations and the hydrological regime, using different spectral indices of vegetation and machine learning algorithms. The Normalized Burn Ratio (NBR) and Moisture Stress Index (MSI) show the highest correlations with defoliation rates. Random Forest was the most accurate model (R2 = 0.79; RMSE = 0.059), showing a high model performance and prediction. Support vector machines and neural networks also demonstrated a high performance (R2 > 0.7). The main hydrological variables selected by the model to explain defoliation were potential evapotranspiration, winter precipitation and maximum summer temperature (lower Out-of-bag error). These results show the importance of hydrological variables involved in evaporation processes, and on the change in the spatial distribution of seasonal rainfall upon the defoliation processes of P. pinaster. These results underpin the importance of integrating temporal remote sensing data and hydrological models to analyze the drivers of forest defoliation and mortality processes in the Mediterranean climate.

‘Leopards’ under the pines: An account of continuity and change in the integration of forest land-uses in Landes de Gascogne, France

The historical record of the definition of forest management and policy principles is a contentious one, characterized by tensions and conflicts between and among public authorities, private stakeholders and citizens. This paper is an empirical and analytical contribution to the understanding of the political and socio-economic factors influencing the integration of stakes in forest-dominated landscapes. Based on a case study of the ‘Landes de Gascogne’ forest region (southwestern France), it explores an apparent paradox that sees local landowners, following a massive storm damage, re-afforesting a Pinus pinaster plantation on a technical basis they know to be vulnerable. The authors highlight how, on which basis and by whom discourses and practices on forest integration have been sustained over decades in ‘Landes’, albeit being in fact reinvented on very different grounds—in a setting similar to the famous quote of the novel Il Gattopardo. The idea of a forest massif is identified as the object of most efforts, enabling the strategical use of three entwined perspectives: as a cultivated forest, a multifunctional land-use and an integrated chain. Ending with an analysis of the interplays of these dimensions, the paper further demonstrates the relevance of landscape and relational approaches to grasp the determinants of forest land-use conflicts.

Root Infection of Canker Pathogens, Fusarium circinatum and Diplodia sapinea, in Asymptomatic Trees in Pinus radiata and Pinus pinaster Plantations

The existence of a latent stage within host tissue of the pine pathogens Fusarium circinatum and Diplodia sapinea, the causal agents of pitch canker and shoot blight disease respectively, has previously been cited. However, studies on this cryptic phase in each disease lifecycle has only been focused on the host aerial parts but not on the roots. Therefore, our objective was to analyze the presence of both pathogens in roots of non-symptomatic mature trees in plantations where the pathogens are known to be causing canker symptoms. For that, we sampled roots from ten non-symptomatic and ten symptomatic trees in three Pinus radiata and one Pinus pinaster plantations in Basque Country, Spain. Both pathogens were isolated from roots of non-symptomatic trees in a higher frequency than from roots of symptomatic trees, 23.3% and 6.6% respectively for D. sapinea and 16.6% and 3.3% respectively for F. circinatum. Neither pathogens was detected in the P. pinaster plantation. The two pathogens were never isolated from the same tree. A high molecular variability was observed for D. sapinea isolates with six different haplotypes and two mating types for the eleven characterized isolates, but only one haplotype and mating type was found for F. circinatum, with all isolates of both fungi being proved pathogenic. These results evidence the importance root infection may have in the disease lifecycle and, therefore, disease management.

Combined demographic and resource models quantify the effects of potential land-use change on the endangered Carnaby's cockatoo (Calyptorhynchus latirostris)

Measuring how land-use changes affect the availability of resources for threatened species is critical for conservation policy and management. Combining demographic population models with models of food supply provides a means of quantifying the relative effects of land-use change and life-history characteristics on population viability. However, few phenomenological population models explicitly link demography to food supply, probably because of the lack of sufficient quantitative data necessary to estimate them. We synthesized detailed demographic and food resource data to model future population size and extinction risk of the endangered Carnaby's cockatoo Calyptorhynchus latirostris under potential land-use scenarios in a rapidly expanding urban region. Carnaby's cockatoo relies primarily on the annual seed crops of native Banksia spp. woodlands and introduced Pinus pinaster plantations. Population viability analysis was combined with estimates of food resources and a daily ration model to estimate carrying capacity, predict the number of birds that could be supported in the region, and the extinction risk. Assuming no changes in the extent or quality of breeding habitat, and current breeding or survival rates, the most important factor currently limiting population growth for Carnaby's cockatoo is adult survival rate, whereas population size is limited by recurring bottlenecks in food availability resulting from a trend of resource depletion combined with large variability in annual seed production.

Environmental Factors Governing Soil Water Repellency Dynamics in a Pinus Pinaster Plantation in NW Spain

AbstractSoil water repellency (SWR) is a dynamic property that changes throughout the year. The objective of this work was to identify the environmental factors governing the temporal patterns in SWR in a pine plantation in northwest Spain with a view of predicting its occurrence and persistence. For this purpose, 24 samples were collected from the soil surface (0–5 cm) at 25 different times over a 1‐year period and analysed for SWR by using water drop penetration time test and soil moisture measurements. Temporal variations in SWR exhibited a well‐defined seasonal pattern. The soil surface was largely wettable from late autumn to early spring and extremely water repellent during summer and early autumn. Repellency persistence was rather variable during spring. There was highly significant correlation between SWR and soil moisture content. The moisture range defining the presence or absence of repellency under field conditions was 22–57%. There were also significant correlations with the target variables (maximum temperature, minimum temperature, precipitation and water balance during variably long antecedent periods), with coefficients that increased with increasing length of the antecedent period considered. The moisture content of soil at the time of sampling and the average maximum temperature for the 28 days before sampling are the best predictors of occurrence of SWR and its persistence in different seasons. Copyright © 2015 John Wiley & Sons, Ltd.

Effects of prescribed fire on surface soil in a Pinus pinaster plantation, northern Portugal

In order to decrease the risk of severe wildfire, prescribed fire has recently been adopted in Portugal and elsewhere in the Mediterranean as a major tool for reducing the fuel load instead of manual or mechanical removal of vegetation. There has been some research into its impact on soils in shrublands and grasslands, but to date little research has been conducted in forested areas in the region. As a result, the impact of prescribed fire on the physico-chemical soil characteristics of forest soils has been assumed to be minimal, but this has not been demonstrated. In this study, we present the results of a monitoring campaign of a detailed pre- and post-prescribed fire assessment of soil properties in a long-unburnt P. pinaster plantation, NW Portugal. The soil characteristics examined were pH, total porosity, bulk density, moisture content, organic matter content and litter/ash quantity. The results show that there was no significant impact on the measured soil properties, the only effect being confined to minor changes in the upper 1 cm of soil. We conclude that provided the fire is carried out according to strict guidelines in P. pinaster forest, a minimal impact on soil properties can be expected.

Estabilidad de los agregados de un suelo quemado a diferentes intensidades de fuego dieciocho años después de un incendio forestal

In 2012, eighteen years after a forest fire that took place in 1994 and burned a Pinus pinaster plantation, the soil aggregate stability is analysed and compared with aggregates of an unburned control area. The burned area was divided into three zones just after the fire, low, medium and high intensity fire, depending on the intensity at which burned each of the three zones. The results of the sampling in 2012, were compared to the analysis of the soil aggregates in 1994 and 1995. The results show that after eighteen years the aggregates of the burned zones are less stable based on two analytical methods, and the differences between burned areas not significant. The fact that the soil of the control zone has more organic matter and concentration of chemical elements like, calcium, magnesium and iron, seems to be the determining factor of greater stability of surface aggregates in the control zone.

Transforming Pinus pinaster forest to recreation site: preliminary effects on LAI, some forest floor, and soil properties

This study investigates the effects of forest transformation into recreation site. A fragment of a Pinus pinaster plantation forest was transferred to a recreation site in the city of Bartın located close to the Black Sea coast of northwestern Turkey. During the transformation, some of the trees were selectively removed from the forest to generate more open spaces for the recreationists. As a result, Leaf Area Index (LAI) decreased by 0.20 (about 11%). Additionally, roads and pathways were introduced into the site together with some recreational equipment sealing parts of the soil surface. Consequently, forest environment was altered with a semi-natural landscape within the recreation site. The purpose of this study is to assess the effects of forest transformation into recreation site particularly in terms of the LAI parameter, forest floor, and soil properties. Preliminary monitoring results indicate that forest floor biomass is reduced by 26% in the recreation site compared to the control site. Soil temperature is increased by 15% in the recreation site where selective removal of trees expanded the gaps allowing more light transmission. On the other hand, the soil bulk density which is an indicator of soil compaction is unexpectedly slightly lower in the recreation site. Organic carbon (C(org)) and total nitrogen (N(total)) together with the other physical and chemical parameter values indicate that forest floor and soil have not been exposed to much disturbance. However, subsequent removal of trees that would threaten the vegetation, forest floor, and soil should not be allowed. The activities of the recreationists are to be concentrated on the paved spaces rather than soil surfaces. Furthermore, long-term monitoring and management is necessary for both the observation and conservation of the site.

Variation in the Abundance and Reproductive Characteristics of Great TitsParus majorin Forest and Monoculture Plantations

Abstract. Natural forests have been progressively replaced by other forest types, mainly monoculture plantations. We compared the abundance of Great Tits and its main food competitors, the Chaffinch Fringilla coelebs and other tits species (Blue Tit Cyanistes caeruleus, Coal Tit Periparus ater and Crested Tit Lophophanes cristatus), and breeding parameters of Great Tits in four forest types: a mixed forest, a native broadleaf forest, a Maritime Pine Pinus pinaster plantation and a Blue Gum Eucalyptus globulus plantation in Central Portugal. The breeding parameters (laying date, clutch size, egg volume, hatching success, fledging success and chick body mass) were collected from nest boxes placed in the four forest types. The censuses indicated a higher abundance index of Great Tit and its food competitors in the mixed and broadleaf forest, when compared to the monoculture plantations. Occupancy rate of nest boxes was not directly related with tit abundance due to differences in the availability of natural ...

Efeito da cinza de biomassa na dinâmica do C e N do solo de uma plantação de Pinus pinaster

Effects of wood ash (loose and pelleted) on chemical properties and microbial activity in an Arenosol from a Pinus pinaster plantation were assessed through laboratory incubation. Wood ash was applied at a rate of 0, 4 and 8 g kg-1 soil both alone or together with N. Loose ash significantly increased pH values and extractable nutrients from the soil. Net nitrification was stimulated by it application. Amounts of microbial biomass C were lower in soils with loose ash than in the control. Basal respiration was not affected by treatments. Effects increased with the increment of applied ash and when applied together with N. Application of pelleted ash produced smaller changes in soil chemical characteristics, net nitrification and C dynamic. Results suggest that, in N limited soils, wood ash should be applied in the pelleted form because changes in chemical soil properties are slower and the potential loss of N is much less as compared to the loose ash. Pelleted ash should be applied together with N fertilizer to improve soil N availability.

Nutritional status and genetic variation in the response to nutrient availability in Pinus pinaster. A multisite field study in Northwest Spain

The low nutrient availability of the acidic and sandy soils of Galicia (Northwest Spain) is probably the main environmental factor limiting forest primary productivity in the area. These particular edaphic conditions could have imposed selective pressures on maritime pine populations leading to specific local adaptations. We first assessed the nutritional status of 22 young contemporary Pinus pinaster plantations in Northwest Spain, and then analysed the response to fertilization in three family × fertilization trials, and how this response varied across sites and genotypes. Growth of P. pinaster in Northwest Spain appeared to be largely limited by nutrient availability, where most of the plantations showed severe nutrient deficiencies, especially in P and Mg. According to these deficiencies, a strong positive response to nutrient additions was observed in the three trials, with height increments of up to 30% compared with the unfertilized control. However, the response to fertilizers was very variable from site to site, and in some cases did not agree with the foliar nutritional diagnosis. The response to fertilization was also significantly affected by pine genotype, suggesting that the plastic response to nutrient additions within each environment was under genetic control. However, the family response to nutrient availability was not consistent across sites, and no significant differences among families were observed for the RDPI plasticity index – a single index that summarizes the phenotypic change in multiple environments – when analysed across environments. The strong environmental component modulating phenotypic responses to fertilization could impose an important obstacle to evolve specific adaptations to the local edaphic conditions, as well as to artificially select genotypes adapted to different environments and silviculture regimes.

Evaluation of the phosphorus status of P-deficient podzols in temperate pine stands: combining isotopic dilution and extraction methods

Phosphorus (P) is often a limiting factor of forest growth but our knowledge of the processes governing P availability in forest soils is rather limited. In the present work, we combined a isotopic dilution method with extraction methods to evaluate the P status in Pinus pinaster plantation forests on highly P-deficient soils. Total, organic, and inorganic P, dissolved and diffusive P, i.e. ionic P species that can be transferred from the solid phase to the soil solution due a gradient of concentration, were determined to a soil depth of 120 cm in a gradient of 18 forest sites (seven humid sites, five mesic sites, and six dry sites). Our objective was to assess the potential contribution of organic and inorganic P to plant available P. Based on results and our original assumptions, we observed that the contribution of organic P fractions (mineralization of soil organic P) to P availability related to the contribution of inorganic P fractions (diffusive P for durations up to 1 year) was predominant in litter, less important in top soil horizons, and negligible at depths below 30 cm. This was partly due to a decreasing proportion of organic P and an increasing proportion of diffusive P with soil depth. Owing to a very low amount of diffusive P in the top soils in dry sites, the relative contribution of organic P was actually higher in these sites than in humid and mesic sites, despite a lower overall organic P fraction. The combination of extraction and isotopic dilution methods in our study shed new light on P status in this forest range. In particular, these methods enable assessment of both the size of the pools and their dynamic fractions.

The spatial distribution of birds and carabid beetles in pine plantation forests: the role of landscape composition and structure

AbstractAim To evaluate the joint and independent effects of spatial location, landscape composition and landscape structure on the distribution patterns of bird and carabid beetle assemblages in a mosaic landscape dominated by pine plantation forests.Location A continuous 3000‐ha landscape mosaic with native maritime pinePinus pinasterplantations of different ages, deciduous woodlands and open habitats, located in the Landes de Gascogne forest of south‐western France.Methods We sampled breeding birds by 20‐min point counts and carabid beetles by pitfall trapping using a systematic grid sampling of 200 points every 400 m over the whole landscape. Explanatory variables were composed of three data sets derived from GIS habitat mapping: (1) spatial variables (polynomial terms of geographical coordinates of samples), (2) landscape composition as the percentage cover of the six main habitats, and (3) landscape structure metrics including indices of fragmentation and spatial heterogeneity. We used canonical correspondence analysis with variance partitioning to evaluate the joint and independent effects of the three sets of variables on the ordination of species assemblages. Moran'sIcorrelograms and Mantel tests were used to assess for spatial structure in species distribution and relationships with separate landscape attributes.Results Landscape composition was the main factor explaining the distribution patterns of birds and carabids at the mesoscale of 400 × 400 m. Independent effects of spatial variables and landscape structure were still significant for bird assemblages once landscape composition was controlled for, but not for carabid assemblages. Spatial distributions of birds and carabids were primarily influenced by the amount of heathlands, young pine plantations, herbaceous firebreaks and deciduous woodlands. Deciduous woodland species had positive responses to edge density, while open habitat species were positively associated with mean patch area.Main conclusions Forest birds were favoured by an increase in deciduous woodland cover and landscape heterogeneity, but there was no evidence for a similar effect on carabid beetles. Fragmentation of open habitats negatively affected both early‐successional birds and carabids, specialist species being restricted to large heathlands and young plantations. Several birds of conservation concern were associated with mosaics of woodlands and grasslands, especially meadows and firebreaks. Conserving biodiversity in mosaic plantation landscapes could be achieved by the maintenance of a significant amount of early‐successional habitats and deciduous woodland patches within a conifer plantation matrix.

Comparing and Combining Stem Analysis and Permanent Sample Plot Data in Site Index Models

Abstract Most site index models are built either from repeated measurements on permanent sample plots or by using data obtained by stem analysis. Sometimes both types of data are available. It is then of interest to test them for consistent height-age trends, and to estimate model parameters using all the data. Efficient procedures should take into account the difference in error patterns between the two data sources. A stochastic differential equation model is proposed in which trend and error parameters can take either different or common values for various data groups. All parameters are simultaneously estimated by maximum-likelihood, and computed likelihoods and likelihood-ratio tests can be used for comparing model variants and for hypothesis testing. The methods are applied to Pinus pinaster plantations in northern Spain. FOR. SCI. 51(4):277–283.

Aboveground productivity and nutrient dynamic in a reforestation of Pinus pinaster Ait. with different intensities thinning

Thinning of different intensity have been carried out on a Pinus pinaster plantation and results have been compared with that of a control treatment and one plot with the maximum biological density for this species and age. The experimental design consists of randomized blocks. Four inventories were made in summer in 1984, 1988, 1992 and 1996. With this information the volume, basal area and number of tree before thinning, thinning and after thinning were calculated. Standing biomass and mineral element concentration before thinning, biomass removed with thinning and standing biomass after thinning have been estimated trough inventories and subsequent determination of modular values (a sample with 100 trees). Litter fall represented by needles fall and dead branches has been measured as well as its evolution through the year on plots representing four different stand densities.

Effects of thinning, fertilisation and sheep grazing on the understory vegetation of Pinus pinaster plantations

Afforestation with pines is a common practice in Mediterranean countries but the spacing employed is usually too dense to allow the growth of sufficient understory vegetation for profitable livestock grazing. In a 17-year-old Pinus pinaster Aiton plantation, established at a density of 1200 trees ha −1 in a semi-arid mediterranean environment of Macedonia, Greece, three degrees of thinning (control, 50% and 75% of trees removed), two levels of fertilisation (control and 1000 kg ha −1 of NPK fertiliser), and two grazing intensities (control and 0.8 sheep ha −1 year −1) were applied. All stands were seeded with 30 kg ha −1 of Dactylis glomerata L. seed. Measurements included cover and species composition, herbage production and nutrient content of the understory vegetation for three consecutive growing seasons. It was found that thinning and fertilisation significantly increased vegetative cover and herbage production by favouring the establishment of the seeded grass as well as other spontaneous species while a significant interaction also appeared between them. Grazing, however, significantly reduced understory vegetation. Applied nutrients were reduced by thinning and grazing while other nutrients such as Ca, Mg and Na were not affected by any treatment. It is concluded that thinning of dense P. pinaster stands up to 300 trees ha −1 and seeding palatable range grasses substantially improves grazing conditions for sheep. This improvement becomes impressive with NPK fertilisation, which increases herbage production and ameliorates its nutrient content even under fairly dense pine stands.