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Abstract In recent years, there has been growing interest in public valuation for forest ecosystem services in policymaking. This paper investigates the public’s perception of the Czech forest ecosystem services, i.e., provisioning, regulating and cultural services, with associated factors (changes in forest cover, production, and respondents’ characteristics). The performance perception of forest ecosystem services was gathered from a nationwide survey in 2020. The Coordination of Information on the Environment Land Cover information in 2000 and 2018 was used for observation of forest cover changes. Coniferous and non-coniferous (broadleaved) roundwood, mushroom, and bilberry production data from the observed years were acquired from the Czech Statistical Office and the Ministry of Agriculture’s annual nationwide surveys. The Bohemia vs. Moravia study areas were also statistically compared. Predictor analysis of the high score of performance perception from individual and cluster forest ecosystems was also performed to answer the research objectives. The group of forest provisioning services received high scores in public evaluation (from 3.9 to 4.2), followed by regulating services (mean range: 3.7–4.1). The highest score was found in forest as a natural habitat for wild animals and plants (mean: 4.6). However, the lowest value was the esthetic value (mean: 2.3). Both are categorized as forest cultural services. The broadleaved and mixed forest areas in 2018 were significantly higher than in 2000, especially in Bohemia. Meanwhile, the total coniferous forested region in 2018 declined substantially compared to 2000 (p = 0.030), especially in Moravian areas. A significantly higher total production of the coniferous and broadleaved roundwood removals in 2018 than in 2000 was reported, in contrast to a marked decrease in collected mushrooms and bilberries. The high score of performance perception of forests as the wood provisioning service was positively and significantly associated with the changes in broadleaved roundwood removals. Older-age and female respondents were the primary predictors of the studied cluster and individual forest ecosystem services. The findings indicate that the social value of the individual forest provisioning services supports the implementation of multi-species and multi-purpose forests; hence, it encourages the implementation of the current Czech forest policy.

In recent years, there has been growing interest in public valuation for forest ecosystem services in policymaking. This paper investigates the public's perception of the Czech forest ecosystem services, i.e., provisioning, regulating and cultural services, with associated factors (changes in forest cover, production, and respondents' characteristics). The performance perception of forest ecosystem services was gathered from a nationwide survey in 2020. The Coordination of Information on the Environment Land Cover information in 2000 and 2018 was used for observation of forest cover changes. Coniferous and non-coniferous (broadleaved) roundwood, mushroom, and bilberry production data from the observed years were acquired from the Czech Statistical Office and the Ministry of Agriculture's annual nationwide surveys. The Bohemia vs. Moravia study areas were also statistically compared. Predictor analysis of the high score of performance perception from individual and cluster forest ecosystems was also performed to answer the research objectives. The group of forest provisioning services received high scores in public evaluation (from 3.9 to 4.2), followed by regulating services (mean range: 3.7–4.1). The highest score was found in forest as a natural habitat for wild animals and plants (mean: 4.6). However, the lowest value was the esthetic value (mean: 2.3). Both are categorized as forest cultural services. The broadleaved and mixed forest areas in 2018 were significantly higher than in 2000, especially in Bohemia. Meanwhile, the total coniferous forested region in 2018 declined substantially compared to 2000 (p = 0.030), especially in Moravian areas. A significantly higher total production of the coniferous and broadleaved roundwood removals in 2018 than in 2000 was reported, in contrast to a marked decrease in collected mushrooms and bilberries. The high score of performance perception of forests as the wood provisioning service was positively and significantly associated with the changes in broadleaved roundwood removals. Older-age and female respondents were the primary predictors of the studied cluster and individual forest ecosystem services. The findings indicate that the social value of the individual forest provisioning services supports the implementation of multi-species and multi-purpose forests; hence, it encourages the implementation of the current Czech forest policy. [ABSTRACT FROM AUTHOR]

Beetles living in dead wood are species-specific, suggesting that beetle diversity may vary between different deciduous tree species. However, the patterns of diversity variation among deciduous trees are still poorly understood. In this study, we investigated the diversity of beetles associated with dead wood in the second decay stage in four protected areas of Lithuania, using trunk-emergence traps on Alnus glutinosa L., Gaertn. (black alder), Betula sp. L. (birch), Fraxinus excelsior L. (European ash), Populus tremula L. (European aspen), Quercus robur L. (common oak), and Tilia cordata Mill. (small-leaved linden). The findings of our study indicated variation in beetle diversity among the six tree species examined. We identified the greatest diversity of beetles in the decaying trunks of Quercus robur, followed by T. cordata, and F. excelsior. Our cluster analysis suggested a higher similarity in beetle diversity among tree species sharing the same type of bark; however, our db-RDA analysis showed that tree species explained more variance in the data than bark type. Our results support previous research highlighting the importance of dead wood species diversity in maintaining the diversity of beetles in forests. Within the context of current biodiversity decline, understanding the similarities or differences in beetle communities between tree species is key to tackling the loss of insect species. [ABSTRACT FROM AUTHOR]

Over various terrain types, natural forests exhibit tree size and biomass variation. We started long- term research that consists of forest vegetation surveys in the Dinghushan National Nature Reserve to comprehensively investigate productivity based on the structure and species composition of China’s forest communities. We grouped the trees into three categories, i.e., as large or mature (DBH > 30 cm), medium-sized or growing (DBH 10–30 cm), and small-sized or regenerating seedlings (DBH

Climate change is an important issue that increasingly affects our lives. One of the proposals for mitigating climate change is fighting biodiversity loss, which can support climate mitigation and adaptation actions. In Poland, the possibility of excluding large tracts of forest areas from use is being considered. The discussed the exclusion of forest land from use will affect the timber supply and market, especially for broadleaved wood. The main purpose of this analysis is to present a timber supply forecast, with a particular focus on the possibility of obtaining broadleaved hardwood timber in Poland from forests managed by State Forests National Forest Holding under three scenarios that assume different criteria for selecting forest areas for protection. The work was divided into two main phases: (1) the analysis of historical sales volume of wood products and average sale prices of hardwood during the period 2011–2020; (2) the preparation of a forecast of the potential possibility of maintaining broadleaved hardwood production in the three decades between 2020 and 2049. In the forecast, it was assumed that about 2.7 million hectares of planted and production forests are excluded from use in order to implement the provisions of the 2030 Biodiversity Strategy. In Scenario "I", the supply of merchantable broadleaved roundwood volume will be reduced to 14%–18% that of Scenario "0". In Scenario "II", 55% of the "0" scenario is harvested, and in Scenario "III", 33%–37% of the "0" scenario merchantable broadleaved roundwood is harvested. The introduction of restrictions on timber harvesting as a result of Poland's compliance with European Union requirements in the area of environmental protection will lead to a significant reduction in the supply of timber on the market. This may lead to a further increase in timber prices and an increase in the importance of large timber buyers at the expense of local buyers. The recommendations contained in the policy objectives that the EU sets for the states should be supported by a thorough analysis when selecting areas for strict protection. [ABSTRACT FROM AUTHOR]

• Combining Sentinel-1/-2 and a DTM improved classification in complex terrain. • Sentinel-2 predictors were more contributive than Sentinel-1. • Higher accuracies were achieved compared to Copernicus HRL 2018 DLT. • UNET outperformed random forest by single usage of Sentinel-1 predictors. • Map accuracy assessment using independent NFI plot data. Countrywide winter and summer Sentinel-1 (S1) backscatter data, cloud-free summer Sentinel-2 (S2) images, an Airborne Laser Scanning (ALS)-based Digital Terrain Model (DTM) and a forest mask were used to model and subsequently map Dominant Leaf Type (DLT) with the thematic classes broadleaved and coniferous trees for the whole of Switzerland. A novel workflow was developed that is robust, cost-efficient and highly automated using reference data from aerial image interpretation. Two machine learning approaches based on Random Forest (RF) and deep learning (UNET) for the whole country with three sets of predictor variables were applied. 24 subareas based on aspect and slope categories were applied to explore effects of the complex mountainous topography on model performances. The reference data split into training, validation and test data sets was spatially stratified using a 25 km regular grid. Model accuracies of both RF and UNET were generally highest with Kappa (K) around 0.95 when predictors were included from both S1/S2 and the topographic variables aspect, elevation and slope from the DTM. While only slightly lower accuracies were obtained when using S2 and DTM data, lowest accuracies were obtained when only predictors from S1 and DTM were included, with RF performing worse than UNET. While on countrywide level RF and UNET performed overall similarly, substantial differences in model performances, i.e. higher variances and lower accuracies, were found in subareas with northwest to northeast orientations. The combined use of S1/S2 and DTM predictors mitigated these problems related to topography and shadows and was therefore superior to the single use of S1 and DTM or S2 and DTM data. The comparison with independent National Forest Inventory (NFI) plot data demonstrated precisions of K around 0.6 in the predictions of DLT and indicated a trend of increasing deviations in mixed forests. A comparison with the Copernicus High Resolution Layer (HRL) DLT 2018 revealed overall higher map accuracies with the exception of pure broadleaved forest. Although, spatial patterns of DTL were overall similar, UNET performed better than RF in areas with a distinct DLT on forest stand level, with the largest differences occurring when only S1 and DTM data was used. In contrast, predictions obtained from RF were more accurate in mixed stands. This study goes beyond the case study level and meets the requirements of countrywide data sets, in particular regarding repeatability, updating, costs and characteristics of training data sets. The 10 m countrywide DLT maps add complementary and spatially explicit information to the existing NFI estimates and are thus highly relevant for forestry practice and other related fields. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the presence of fungi and water molds in 13 state and 3 private nurseries in Sakarya, Kocaeli, Yalova, Bursa, Istanbul, Kırklareli and Edirne provinces where woody plants were produced. For this purpose, the coniferous and deciduous seedlings showing various disease symptoms, especially death and drying, were sampled together with their soil. Laboratory studies included microscopic investigations and isolation of fungi from diseased tissues and isolation of Pythiaceous species from soil samples of sampled seedlings. Two hundred twenty-seven deciduous and coniferous seedlings and 79 soil samples were taken from the nurseries. Totally 145 fungal and 57 Pythiaceous isolates were obtained. The isolates were grouped into morphotypes based on their morphological characteristics, and representative isolates were identified by ITS-based DNA analysis. Marssonina brunnea, Melampsora allii-populina on poplar and Dothistroma septosporum on pine were the fungal disease agents detected based on their morphological and microscopical properties. In addition to these species, Fusarium solani, Fusarium oxysporum, Pythium aphanidermatum, Pythium irregulare, Pythium ultimum, Phytopythium vexans and Phytophthora syringae were among other important and common species identified. The surveys and laboratory studies conducted within the scope of this research showed that state nurseries host more fungal and Pythiaceous species than private nurseries. The amount and diversity of the obtained fungal and oomycete species draws attention to the risk that these microorganisms can be transported from one nursery to another and even to afforestation areas.

Reforestation with different tree species could alter soil properties and in turn affect the bacterial community. However, the effects of long-term reforestation on bacterial community structure and diversity of subtropical forest soils are poorly understood. In the current study, we applied error-corrected barcoded pyrosequencing to characterize the differences in the soil bacterial community in a low mountain, subtropical forest subjected to reforestation. The communities were sampled in the summer and winter from a native broadleaved forest (BROAD-Nat) and two adjacent coniferous plantations, a Calocedrus formosana forest of 80 years (CONIF-80) and a Cunninghamia konishii forest of 40 years (CONIF-40). The soil bacterial communities among three forest types were dominated by Acidobacteria and Alphaproteobacteria. The distribution of abundant genera among communities was different. Based on the Shannon diversity index, the bacterial alpha diversity of CONIF-40 community was significantly higher than that in the CONIF-80 and BROAD-Nat soils. In both of the coniferous plantations, the soil bacterial diversity in summer was also higher than that in winter. Distribution of some abundant phylogenetic groups, K-shuff and redundancy analysis of beta diversity among communities showed that the bacterial structure of three soil communities differed between two seasons. These results suggest that seasonal differences influence the diversity and structure of bacterial soil communities and that the communities remain different even after a long period of reforestation.

Analysis of the impacts of social structure on the behaviour and life history of birds is a rapidly developing area of ornithology. Such studies commonly focus on the Paridae (tits and chickadees) as a model group, but detailed assessment of the basic social structure is lacking for many parids, particularly in the non-breeding season. Such baseline information is essential for understanding the organisation of bird populations, including associations between individuals within social and spatial networks. We assessed the non-breeding (autumn-winter) social structure and that during spring (i.e. the breeding season) for Coal Tits Periparus ater in broadleaved forest in southern Britain. Coal Tits were found to be resident and sedentary in this habitat, with birds remaining close to their spring territories during the non-breeding season and associating in small groups averaging 3-4 individuals. Associations were variable, however, with no evidence of stable flock membership, group territoriality or strong pair bonds during autumn-winter. The non-breeding social structure during a year of high population density did not differ from that during a year of low population density, being most similar to a 'basic flock' organisation. This contrasted with that predicted for a food-hoarding parid, highlighting the potential differences in social behaviour between different populations of bird species. Such variation in social behaviour can inform our understanding of the evolution of avian social structures and associated behavioural traits, such as food hoarding, and aid the interpretation of intra- and interspecific differences in behaviour. [ABSTRACT FROM AUTHOR]

Reforestation with different tree species could alter soil properties and in turn affect the bacterial community. However, the effects of long-term reforestation on bacterial community structure and diversity of subtropical forest soils are poorly understood. In the current study, we applied error-corrected barcoded pyrosequencing to characterize the differences in the soil bacterial community in a low mountain, subtropical forest subjected to reforestation. The communities were sampled in the summer and winter from a native broadleaved forest (BROAD-Nat) and two adjacent coniferous plantations, a Calocedrus formosana forest of 80 years (CONIF-80) and a Cunninghamia konishii forest of 40 years (CONIF-40). The soil bacterial communities among three forest types were dominated by Acidobacteria and Alphaproteobacteria. The distribution of abundant genera among communities was different. Based on the Shannon diversity index, the bacterial alpha diversity of CONIF-40 community was significantly higher than that in the CONIF-80 and BROAD-Nat soils. In both of the coniferous plantations, the soil bacterial diversity in summer was also higher than that in winter. Distribution of some abundant phylogenetic groups, K -shuff and redundancy analysis of beta diversity among communities showed that the bacterial structure of three soil communities differed between two seasons. These results suggest that seasonal differences influence the diversity and structure of bacterial soil communities and that the communities remain different even after a long period of reforestation. [ABSTRACT FROM AUTHOR]

Although wall-to-wall, accurate, and up-to-date forest composition maps at the stand level are a fundamental input for many applications, ranging from global environmental issues to local forest management planning, countrywide mapping approaches on the tree type level remain rare. This paper presents and validates an innovative remote sensing based approach for a countrywide mapping of broadleaved and coniferous trees in Switzerland with a spatial resolution of 3 m. The classification approach incorporates a random forest classifier, explanatory variables from multispectral aerial imagery and a Digital Terrain Model (DTM) from Airborne Laser Scanning (ALS) data, digitized training polygons and independent validation data from the National Forest Inventory (NFI). The methodological workflow was optimized for an area of 41,285 km² that is characterized by temperate forests within a complex topography. Whereas high model overall accuracies (0.99) and kappa (0.98) were achieved, the comparison of the tree type map with independent NFI data revealed significant deviations that are related to underestimations of broadleaved trees (median of -3.17%). Constraints of the tree type mapping approach are mostly related to the acquisition date and time of the imagery and the topographic (negative) effects on the prediction. A comparison with the most recent High Resolution Layers (HRL) forest 2012 from the European Environmental Agency revealed that the tree type map is superior regarding spatial resolution, level of detail and accuracy. The high-quality map achieved with the approach presented here is of great value for optimizing forest management and planning activities and is also an important information source for applications outside the forestry sector. [ABSTRACT FROM AUTHOR]

Mechanisms of shade tolerance in tree seedlings, and thus growth in shade, may differ by leaf habit and vary with ontogeny following seed germination. To examine early responses of seedlings to shade in relation to morphological, physiological and biomass allocation traits, we compared seedlings of 10 temperate species, varying in their leaf habit (broadleaved versus needle-leaved) and observed tolerance to shade, when growing in two contrasting light treatments - open (about 20% of full sunlight) and shade (about 5% of full sunlight)., We analyzed biomass allocation and its response to shade using allometric relationships. We also measured leaf gas exchange rates and leaf N in the two light treatments., Compared to the open treatment, shading significantly increased traits typically associated with high relative growth rate ( RGR) - leaf area ratio ( LAR), specific leaf area ( SLA), and allocation of biomass into leaves, and reduced seedling mass and allocation to roots, and net assimilation rate ( NAR). Interestingly, RGR was not affected by light treatment, likely because of morphological and physiological adjustments in shaded plants that offset reductions of in situ net assimilation of carbon in shade. Leaf area-based rates of light-saturated leaf gas exchange differed among species groups, but not between light treatments, as leaf N concentration increased in concert with increased SLA in shade., We found little evidence to support the hypothesis of a increased plasticity of broadleaved species compared to needle-leaved conifers in response to shade. However, an expectation of higher plasticity in shade-intolerant species than in shade-tolerant ones, and in leaf and plant morphology than in biomass allocation was supported across species of contrasting leaf habit. [ABSTRACT FROM AUTHOR]

According to the results of the current research, a new approach in application of dendrochronology, using broadleaved tree rings, as main element of productivity, to evaluate forest ecosystem productivity, has been introduced. In this investigation, tree ring widths of sample cores which have been taken by borer from various species at different elevations, have been analyzed to evaluate their productivity and possible competitions between species. Ecological application of dendrochronology is main aspect of this study. Results provided in this research, are part of a wide range of dendrochronology study which have been taken during more than six years (started in 2006) to consider climate change impacts on Hyrcanian forest ecosystems. Target species in this study are beech tree (Fagus orientalis Lipsky), oak (Quercus castanaefolia C. A. Mey.), hornbeam (Carpinus betulus L.), alder (Alnus subcordata), and maple (Acer velutinum), which have been selected in Galugah forest district in Mazandaran province. After visiting the forest site and considering the adapting maps, sample cores were collected along a transect line (profile) at three elevation levels, namely 350, 800, and 1380 meters above sea level. Target trees were more or less at same ages. In the study region, during the last 54 years, precipitation trend shows a decrease by 372 mm and temperature trend shows an increase by 0.59 oC. Variability in different species responses to inner (competition between species) and outer elements (environmental and climatic changes), at various elevations are highly dependent on species’ nature. Tree ring widths of Fagus orientalis Lipsky in low elevation during last 55 years has decreased, but tree ring widths of this species in medium elevation in the same period has increased. Tree ring widths of beech tree in high elevation have not changed significantly.

After several years of decreased annual rainfall and water shortages, the Chilean society is demanding that forest plantations take accountability of their role in consuming scarce water resources. Evidence has shown that interception losses are considerable when determining water production in watersheds. The aim of this study was to determine if site and stand variables explain interception losses by Chilean forests for the development of an empirical model that could predict the potential impacts of forest management practices and land-use change. A total of 127 data from annual water balance plot studies in Chile were compiled to derive relationships between interception and precipitation, species composition, plantation age and other stand and site variables. The reviewed data indicated that annual interception losses are mainly explained by annual rainfall and basal area of the forest stands, with a clear difference between the northern (dryer) and southern (wetter) regions of Chile. For a wide latitudinal gradient, forest composition and age, annual interception accounted for approximately 21% of incoming precipitations. Broadleaved forest stands (including native broadleaved and eucalypt forests) generally presented higher interception losses than conifers. Interception was higher in northern zones, indicating that forests have greater impacts on water resources in dryer regions. Our results were compiled in empirical models, which can be used to estimate forest interception in a latitudinal gradient in Chile and to support policy making. These results are also proposed as an approximate analogue of the changes in forest interception losses, which may occur as vegetation belts shift latitudinally as a result of the impact of climate change. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction: Variation in reproductive phenology among species is an important mechanism for maintaining species coexistence. In mixed forests, the impact of limiting (biotic and abiotic) factors on tree reproductive success regulates the maintenance of species in balanced proportions or the conversion towards monospecific forests. This study offer a significant first approach to the reproductive phenology of mixed forests, assessing flowering, seeding and loss factors on reproductive success in three forest types (pure deciduous Nothofagus pumilio (Np), evergreen Nothofagus betuloides (Nb) and mixed (M) forests), comparing also between two geographical locations (coast and mountain), during one growing season. Results: Flowering falling started early in Np. Seed fall occurred first and more concentrated in Np, while in Nb, it was progressive during autumn. Phenology in M combined both patterns, but with better reproductive performance of both species. Seed production was greater in Nb (42,900,000 ha) than in Np (710,000 ha), while M presented intermediate values (31,900,000 ha). Abortion was greatest in Np (19% of female flowers and 10% of immature fruits), while fruit predation was low (7-9%) in all forest types. Empty seed was the main loss factor, but with low net values for each species in M. Regarding geographical location, sea proximity generated a quick starting of the growing season in coast compared to mountain sites. However, we detected forest types × location interactions in flowering and seeding patterns (e.g. in male flower production and in empty and viable seeds), with differences in species response according to location. Conclusions: Both deciduous and evergreen species have reproductive advantages in mixed compared to pure forests. However, mixed were more similar to pure evergreen forests in their reproductive traits and the incidence of the limiting factors. The study of only one growing season does not allow us to conclude whether mixed forests are stable communities, but we contribute to understand the roles of reproductive phenology in mixed forest dynamics. [ABSTRACT FROM AUTHOR]

Although wall-to-wall, accurate, and up-to-date forest composition maps at the stand level are a fundamental input for many applications, ranging from global environmental issues to local forest management planning, countrywide mapping approaches on the tree type level remain rare. This paper presents and validates an innovative remote sensing based approach for a countrywide mapping of broadleaved and coniferous trees in Switzerland with a spatial resolution of 3 m. The classification approach incorporates a random forest classifier, explanatory variables from multispectral aerial imagery and a Digital Terrain Model (DTM) from Airborne Laser Scanning (ALS) data, digitized training polygons and independent validation data from the National Forest Inventory (NFI). The methodological workflow was optimized for an area of 41,285 km2 that is characterized by temperate forests within a complex topography. Whereas high model overall accuracies (0.99) and kappa (0.98) were achieved, the comparison of the tree type map with independent NFI data revealed significant deviations that are related to underestimations of broadleaved trees (median of −3.17%). Constraints of the tree type mapping approach are mostly related to the acquisition date and time of the imagery and the topographic (negative) effects on the prediction. A comparison with the most recent High Resolution Layers (HRL) forest 2012 from the European Environmental Agency revealed that the tree type map is superior regarding spatial resolution, level of detail and accuracy. The high-quality map achieved with the approach presented here is of great value for optimizing forest management and planning activities and is also an important information source for applications outside the forestry sector.

Abstract: The objective of the study was to measure annual carbon sequestration rate of mixed deciduous forest by measuring that of seven young broadleaved tree species (6 years age) as well as selection of better carbon sequestered plant species for future plantation. The diurnal net assimilation rate of Carbon dioxide (CO2) at leaf level was measured with LI-6400 Portable Photosynthesis System at daytime on seasonal basis in a man-made forest at Budge Budge (N 22°28′ E 88°08′) of South 24 Parganas, West Bengal, INDIA. Net assimilation rate of carbon at canopy level was calculated by measuring Leaf Area Index with LAI-2200 and using analytical model with non-rectangular hyperbolic light response curve. The average net assimilation rate of CO2 at leaf level was found maximum in Albizzia lebbek (8.13 μmol m−2 s−1) and that of canopy level in Eucalyptus spp. (4.851 g h−1). The minimum was found for Swietenia mahagoni (1.058 g h−1). The annual carbon sequestration rate of the mixed forest in natural condition was estimated 6.01 t ha−1 year−1 by consolidating the potential of all seven species. [Copyright &y& Elsevier]

ABSTRACT Afforestation of abandoned agricultural lands has been the main change in land use over the past decade in Europe. However, the impact of tree species and understorey management on production and plant diversity over the medium- and long-term has not been thoroughly studied. This paper aims to evaluate the effects of an afforestation of Pinus radiata D. Don and Betula alba L. on soil pH, understorey production and plant diversity and life cycle type (annuals vs. perennials) managed with different soil fertilisation treatments over a period of 11 years. The results show an acidification of the soil 11 years after establishment, better vertical growth and diameter of pine compared with birch as usually happens in the region and important variation in the biomass production and composition of the understorey below both tree species. Understorey species remained similar during the first 5 years below both canopies. However, species richness ( S) was drastically reduced under Pinus radiata D. Don plantation compared to Betula alba L. ( Spine = 2 vs. Sbirch = 17) after 11 years of tree establishment at a very high density (2500 trees ha−1). Inorganic and organic fertilisation also caused a reduction in floristic diversity. Soil pH, pasture production and floristic understorey plant diversity are better preserved under autochthonous broadleaves, which increased the multiple uses of recently afforested lands in the short- and medium-term. In the European context of high need for sawn wood, the use of autochthonous broadleaved tree species like Betula should be promoted due to their better sustainability. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The possibility of estimating young trees biomass is rather limited because forest yield tables are constructed starting from higher thresholds of proxy, such as diameter or height, and lack of availability of allometric equations. The aim of this study is to provide species-specific and general biomass equations for young plants often used for plantations on marginal lands in southern and eastern Romania. Power functions based on log-transformed data were applied to seven tree species (Robinia pseudoacacia (L.), Quercus sp., Populus alba (L.), Gleditsia triacanthos (L.), Elaeagnus angustifolia (L.), Salix alba (L.) and Fraxinus excelsior (L.)), one shrub (Rosa canina L.) and to the overall dataset with all the species pooled together (406 plants), using the diameter at collar height (Dch ), diameter at breast height (Dbh ) or height (H) as single predictor. Dch resulted as being the best predictor for each compartment for very young trees, but H also proved to be a promising individual predictor both for species-specific or general equations. Dbh could satisfactorily predict the aggregated aboveground biomass, but generally could not adequately estimate all biomass components (i.e., belowground biomass or foliage). The goodness of regression was lowest for the foliage and highest for the stem and aggregated biomass compartments. The scaling coefficient (a) and exponent (b) of power functions were influenced both by species-specific factors and by the growth stage of the trees. Parameters to be used for a general equation were also provided for each biomass compartment and predictor. Using Dch as independent variable, we observed that the value of the general scaling exponent estimated to predict total aboveground biomass was the same as the value (2.66) predicted by the WBE functional model. Using Dbh as predictor for the general allometric equation, the resulting value of b (2.36) coincided with the values empirically estimated by previous studies. Equations were finally compared against three independent datasets. Parameters provided by the general equation highlighted permanent overestimation for aggregated biomass compartments and underestimation for branches or roots, but always fell into the range provided by the upper and lower values estimated for a and b. This suggests that, at least for young trees, our equation could be applied without regard for local fertility conditions or plantation management. [Copyright &y& Elsevier]

We report a new version and an empirical evaluation of a forest reflectance model based on photon recollision probability (p). For the first time, a p -based approach to modeling forest reflectance was tested in a wide range of differently structured forests from different biomes. To parameterize the model, we measured forest canopy structure and spectral characteristics for 50 forest plots in four study sites spanning from boreal to temperate biomes in Europe (48°–62°N). We compared modeled forest reflectance spectra against airborne hyperspectral data at wavelengths of 450–2200 nm. Large overestimation occurred, especially in the near-infrared region, when the model was parameterized considering only leaves or needles as plant elements and assuming a Lambertian canopy. The model root mean square error (RMSE) was on average 80%, 80%, 54% for coniferous, broadleaved, and mixed forests, respectively. We suggest a new parameterization that takes into account the nadir to hemispherical reflectance ratio of the canopy and contribution of woody elements to the forest reflectance. We evaluated the new parameterization based on inversion of the model, which resulted in average RMSE of 20%, 15%, and 11% for coniferous, broadleaved, and mixed forests. The model requires only few structural parameters and the spectra of foliage, woody elements, and forest floor as input. It can be used in interpretation of multi- and hyperspectral remote sensing data, as well as in land surface and climate modeling. In general, our results also indicate that even though the foliage spectra are not dramatically different between coniferous and broadleaved forests, they can still explain a large part of reflectance differences between these forest types in the near-infrared, where sensitivity of the reflectance of dense forests to changes in the scattering properties of the foliage is high. • First extensive empirical evaluation of a forest reflectance model using p -theory. • New parameterization taking into account woody elements and directional scattering. • Uncertainties of the modeled forest reflectance reduced in the near-infrared region. • Forest spectra and their relationships with plant area index simulated correctly. • Based on field and airborne data in 50 forest plots from boreal to temperate biomes. [ABSTRACT FROM AUTHOR]

Competition from weeds is the most important yield reducing factor in African rice production systems. Generally important weed management practices in rice are controlled flooding and the use of herbicides. Smallholder rice farmers in Africa however often lack the necessary water management infrastructure, access to affordable, good quality herbicide products and knowledge and equipment for their safe and effective application. Against this challenging backdrop, effective and affordable weed management strategies are highly needed. The literature on weed ecology and management in African rice systems is systematically reviewed to assess achievements in the last quarter of the past 50 years of international rice research endeavours, the period since the last comprehensive review (2009), and to propose the way forward for research and development. Most published studies are from West Africa and focussed on rainfed upland (43% of all relevant studies) or rainfed lowland (32%) rice. Grasses are the most frequently studied weed types, closely followed by parasitic weeds and broadleaved weeds (ex aequo). Most research (75% of published studies) focussed on weed management, mostly referring to or including curative measures (e.g., chemical, manual) or preventive weed management options that improve weed competitiveness of the crop (e.g., crop establishment, cultivars), while less attention was observed for preventive measures aiming at reduced weed recruitment or seed bank sizes (e.g., crop rotations, intercropping, mulches) or integrated weed management approaches. Future research should invest more in developing integrated weed management strategies that achieve (1) reduced weed recruitment, (2) reduced weed seed bank sizes and (3) improved crop competitiveness and that are compatible with farmer's production resources, fairly independent of (agrochemical) industries and markets and benign to the environment and human health. We recommend research on parasitic weeds to focus on a further broadening of the range of currently available management options, with a particular focus on the role of soil fertility and more efficient fertiliser technologies that simultaneously improve crop productivity and quality. For research to contribute to the development of meaningful weed management strategies for African rice systems in the future, we believe it would be best to identify and focus on target-location specific weed-communities, and to reconcile field level weed management strategies with the preconditions set at higher system levels (e.g., farming and agricultural systems) and anticipated scenarios regarding changing demographics and biophysical and institutional environments. • The literature on weeds and weed management in rice systems in Africa was reviewed. • In the past 50 years, 70% of the relevant publications focussed on weed management. • Most studies are from West Africa (70%) and addressed rainfed rice systems (75%). • The presence of parasitic weeds is another unique feature of African rice systems. • Future research needs to widen the range of preventive weed management strategies. [ABSTRACT FROM AUTHOR]

The forest landscape in the north-west Iberian Peninsula is the result of thousands of years of human intervention. The objective of this study was to describe the evolution and historical background of the forests to establish measures for their conservation and recovery. The main focus was on natural broadleaved forests, which have been intensively exploited ever since Roman times. These forests have been converted to agricultural land, felled for the naval, metallurgical and railway industries, sold along with Church lands, suffered forest fires, and been substituted by fast growing species. All of these activities have led to a reduction in the forest area. Today, broadleaved forests cover small and generally rugged areas, and remain where the terrain often prevents other types of land use. Remains of these forests can be found in flat areas close to villages, but the understorey vegetation and regeneration is limited owing to human activities. Therefore, their present situation raises the problem of their silvicultural and economic transformation. On a positive note, the area covered by these forests has increased recently owing to better awareness about their conservation and to the recognition of habitats of interest by the European Union, as part of the Nature 2000 Network. [ABSTRACT FROM AUTHOR]

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch (Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine (Pinus sylvestris L.) and spruce [Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. [ABSTRACT FROM AUTHOR]