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... The cultivation of Populus spp. on acid soils is difficult mainly due to low nutrient availability, limiting the distribution and use of this marketable tree species. In this paper we report the results of two experiments, in which a granulated highly reactive micronized calcium carbonate (CaCO₃) was tested at increasing levels to improve the effect of NPKS fertilization on poplar growth. Twin fie ...
... The safety of genetically modified forest trees is an important ecological issue worldwide, and concerns about genetic modification are one factor hindering in-depth research and large-scale planting of genetically modified trees. This study evaluated the impact of transgenic poplars on the ecosystem by analyzing differences in arthropod communities, target arthropods, and nontarget arthropods in ...
Populus; administrative management; biomass; carbon; climate change; coasts; drought; equations; field experimentation; fine roots; forests; soil profiles; soil water content; spatial distribution; stand age; total nitrogen; understory; water uptake; China
Abstract:
... Although we know that fine roots play an important role in carbon and nutrient cycling in forest ecosystems, knowledge on how fine root biomass (FRB) and its vertical distribution change with stand age and inter-annual precipitation variability is limited. In this study, we conducted a field experiment to explore the effects of stand age and inter-annual precipitation variability on FRB and its ve ...
Populus; administrative management; carbon; carbon sinks; clearcutting; climate; ecosystems; forest ecology; landscapes; net ecosystem production; net primary productivity; pioneer species; stand development; Michigan
Abstract:
... Effective forest carbon (C) management requires an understanding of how stand-replacing disturbances affect C pools and fluxes over successional timescales, and how the growth of secondary forests compares with that of undisturbed forests. In the upper Great Lakes region, fires that followed clear-cut harvesting shaped a century-old cohort of secondary forests, but the long-term effects of fire on ...
... Populations of large herbivores, including members of the deer family Cervidae, are expanding across and within many regions of the northern hemisphere. Because their browsing on trees can result in economic losses to forestry and strongly affect ecosystems, it is becoming increasingly important to understand how best to mitigate resultant damage. Previous research has highlighted the importance o ...
... Endemic plant pathogens are important agents of many forest processes and contribute to shaping forest ecosystem dynamics and diversity. However, Marssonina leaf spot of poplar is induced by a pathogenic fungus Drepanopeziza populi, causing increased damage to riparian poplars in recent years. And such endemic diseases have received little attention at the landscape scale, despite the key role of ...
Populus; defoliation; forest ecosystems; landscapes; leaf area; leaf dry matter content; leaves; riparian forests; risk assessment; rivers; specific leaf area; tree height; trees; understory; vegetation cover; China
Abstract:
... Tree diversity and landscape features have long been considered as the main drivers of insect herbivory in forest ecosystems. However, relatively little is known about how local and landscape factors, directly and indirectly, acting at different spatial scales affect insect damage under natural, non-outbreak conditions. Here, 30 mixed and pure forest stands were selected in natural forests along t ...
Populus; climate change; clonal variation; cluster analysis; females; field experimentation; forest ecology; genotype; growth performance; males; prioritization; stem form; survival rate; tree growth; trees; wood; wood density
Abstract:
... Climate change brings about more frequent short-term waterlogging leading to unfavorable conditions for tree growth. Poplar is a preferred tree species for fast-growing plantations. Although limited short-term comparative studies exist with poplars that examine clonal variation in growth and physiological responses to waterlogging, a comprehensive assessment on growth performance, crown structure ...
Bryophyta; Picea; Populus; Salix; Sorbus; administrative management; clearcutting; dead wood; ecosystems; habitats; ordination techniques; secondary forests; species richness; trees
Abstract:
... A growing proportion of the boreal biome consists of managed even-aged secondary forest stands regenerated after clear-cutting. Many disturbance-intolerant species may not be able to recolonize or reach their original abundance in these stands before the next clear-cutting, potentially causing large-scale biodiversity losses. Boreal bryophytes (mosses and liverworts) include many species intoleran ...
Ryan C. Burner; Tone Birkemoe; Jörg G. Stephan; Lukas Drag; Jörg Muller; Otso Ovaskainen; Mária Potterf; Olav Skarpaas; Tord Snall; Anne Sverdrup-Thygeson
... Wood-living beetles make up a large proportion of forest biodiversity and contribute to important ecosystem services, including decomposition. Beetle communities in managed southern boreal forests are less species rich than in natural and near-natural forest stands. In addition, many beetle species rely primarily on specific tree species. Yet, the associations between individual beetle species, fo ...
Populus; administrative management; biomass; carbon; coasts; equations; fine roots; forest ecology; nitrogen; nutrient uptake; soil profiles; spatial distribution; China
Abstract:
... Dynamics of fine root biomass (FRB) is fundamental to understanding carbon allocation and storage in forests. However, our understanding of FRB responses and its vertical distribution with respect to atmospheric nitrogen (N) deposition is limited. In this study, we applied five N addition rates (0, 5, 10, 15, and 30 g m⁻² yr⁻¹) to explore effects of N addition on FRB and its distribution patterns ...
Mycoleptodiscus; Plectosphaerella; Populus; administrative management; forests; fungal communities; nitrogen; rhizosphere; soil bacteria; soil fungi; soil pH; species diversity; total nitrogen; China
Abstract:
... The continuous increase of nitrogen (N) deposition has had strong impacts on the structure and health of forest ecosystems globally. An elucidation of the shifts in rhizospheric microbial communities and their interactions with environmental factors under N-addition will assist us with better understanding the responses of forest ecosystems to future environmental changes. In this study, we employ ...
Populus; administrative management; carbon; decline; dieback; embolism; fluid mechanics; forest ecology; hydraulic conductivity; leaves; mortality; risk; starch; sugars; tree crown; trees; water stress; windbreaks; wood; xylem; China
Abstract:
... Populus trees play an important role in windbreak construction in northern China, but widespread decline and mortality of Populus windbreaks have occurred in recent years. The phenomenon of die-backs from the top of Populus trees downwards is commonly found in declining windbreaks preceding tree deaths, particularly in water-limited areas. To provide a mechanistic explanation for such top-down die ...
... A growing portion of woodlands worldwide is allocated to tree plantations. These are intensively managed and support significantly lower biodiversity than natural forests. However, given their rising extension and importance, understanding how to enhance the role of plantations in aiding biodiversity is crucial. In the present study, we assessed the suitability of traditional poplar plantations fo ...
Populus; administrative management; data collection; forest ecology; humans; irrigation management; profitability; society; soil water deficit; surveys; tree growth; trees
Abstract:
... Poplar (Populus spp.) is widely planted around the world and has been closely linked to human beings since ancient times due to its multiple beneficial utilizations both for the environment and society. As one of the fastest-growing tree species in temperate zones, the high growth rate of poplar is associated with its high water-demand, which makes it vulnerable to water deficits. To maintain and ...
... Populus hybrids are increasingly planted in multifunctional bioenergy buffers bordering crop fields. However, such small agroforestry systems are vulnerable to damage caused by overabundant deer populations. We measured after 8 years the effects of white-tailed deer (Odocoileus virginianus), genotype and planting stock type on tree growth and ecosystem services provision (biomass production; energ ...
... Tree diversity has long been described as a major driver of insect herbivory and pathogen damage, which can cause defoliation and sometimes stunted growth of forest trees. However, as few studies have simultaneously considered tree diversity effects on insect pests and fungal pathogens and sufficiently captured other ecological drivers, such as landscape structure and forest stand’s relative posit ...
Betula; Landsat; Picea; Pinus banksiana; Populus; administrative management; boreal forests; burn severity; canopy; drought; fire behavior; fire season; lakes; landscapes; national parks; phenology; species diversity; spring; summer; temperature; Alberta
Abstract:
... Increased global temperature, drought, and extreme weather have increased the frequency and intensity of wildfires in Canadian Boreal forests. We examined how burn severity was related to canopy species composition and proximity to water in six large boreal forest stands across northern Alberta (two in the Bistcho Lake region, three in Wood Buffalo National Park, and one in the Richardson backcoun ...
... In Europe land use change has produced loss and fragmentation of the original forest habitat. On the other hand, the area covered by tree plantations and altered stands dominated by exotic tree species is increasing. Forest specialist birds are considered to be among the best candidates to assess the consequences of this transformation on wildlife. Here we investigate the link between the abundanc ...
Betula pendula; Larix; Picea abies; Populus; administrative management; afforestation; agricultural land; carbon sequestration; coppicing; forest ecology; hybrids; land use change; phytomass; short rotation forestry; soil; soil organic carbon; stand density
Abstract:
... Changing land use from agriculture to forestry affects global carbon (C) balances. In addition to reduce using fossil fuels, climatic benefits may be reached by increasing forested areas where appropriate. At present, there is limited data concerning whether differences in C sequestration rates occur among tree species. In this study we evaluated the effects of various species on C sequestration a ...
Populus tremula; Populus tremuloides; acclimation; air; asexual reproduction; bioenergy; climate change; climate models; coppicing; elevated atmospheric gases; forests; humid zones; humidification; hybrids; latitude; long term effects; mortality; pulp; relative humidity; tree growth; tree height; trees; Estonia
Abstract:
... Aspens are fast-growing clonal trees with a wide circumboreal distribution range, suitable for the production of pulp and bioenergy. The adaptability of aspen short-rotation coppice systems to climate change has rarely been investigated. For a large part of aspens’ northern range, climate models predict an increase in precipitation and, consequently, in atmospheric humidity. Our aim was to clarify ...
... Predicting forest succession is not a trivial pursuit and has remained a central challenge for scientists and foresters for well over a century. While thousands of papers have been published on the topic, contributing to a plethora of concepts and terminologies, there remains confusion over causal mechanisms, inhibiting our ability to adopt many lessons learned to sustainable forest management. Ba ...
Populus; drought; ecosystems; gas exchange; global warming; leaves; mesophyll; ozone; photosynthesis; physiological response; plant growth; saplings; specific leaf weight; stomatal conductance; stomatal movement; water supply; water use efficiency
Abstract:
... Elevated ground-level ozone (O₃) concentrations decrease photosynthetic biochemistry more than stomatal conductance (gₛ), leading to an overall reduction in leaf-scale water use efficiency (WUE). Global warming is expected to lead to more severe and frequent droughts resulting in stomatal closure, increased WUE, and potentially in reduced plant O₃ uptake and damage. It is currently unclear how the ...
... Ozone (O3) pollution and drought are frequent in summer, which adversely affects plant growth. In this study, we investigated the interactive effects of O3 and water deficit on growth parameters, and carbon (C) and nitrogen (N) stocks and their allocation to different organs in poplar saplings in the summer of 2017. The saplings were subjected singularly and in combination to two chronic O3 treatm ...
Pinus; shade tolerance; decision making; forests; Nyssa; Quercus; Carya; Fraxinus; habitat fragmentation; Populus; Betula; databases; fire resistance; Ulmus; decline; introduced species; Acer; Prunus; climate change; forest inventory; stand basal area; Eastern United States
Abstract:
... Forest ecosystems in the United States (U.S.) are facing major challenges such as climate change, exotic species invasions, and landscape fragmentation. It is widely believed that forest composition in the eastern U.S. is transitioning from shade-intolerant, fire-tolerant species to shade-tolerant, fire-intolerant species, but most evidence is anecdotal or localized. No comprehensive studies exist ...
Populus; biocompatible materials; bioenergy; biomass; byproducts; chronosequences; feedstocks; forest growth; forests; guidelines; historical records; primary productivity; research programs; soil carbon; soil chemical properties; soil productivity; soil quality; soil types; stand establishment; Great Lakes region; Michigan
Abstract:
... Harvest residues are an abundant by-product of commodity management in working forests, with significant potential as feedstock for bioenergy and advanced biomaterials. While contemporary experimental research programs seek to determine the short-term impacts of intensive residue removal on soil conditions and site productivity, rotation-length implications in operational settings remain speculati ...
... Published literature shows contrasting effects of fertilization in forest plantations. The objective of this study was to determine the effects of early Nitrogen (N) fertilization on the growth of four hybrid poplar clones (Katepwa, Hill, Okanese, Walker) at two contrasting sites in the Boreal Plains ecozone of Canada. Using ammonium nitrate fertilizer, three N fertilizer rates were applied annual ...
... Mine wastes create harsh recruitment conditions for forest tree seedlings, especially waste rock piles where erodible slopes are prone to drought. Plantations using fast-growing tree species can potentially accelerate the conversion of degraded mine sites into forests through facilitation of tree recruitment, while contributing to the stability of slopes. In this study, hybrid poplars were tested ...
Populus; bioenergy; biomass production; carbon; coppicing; deficit irrigation; drought; environmental factors; growing season; growth rings; hybrids; irrigation scheduling; microirrigation; monitoring; plant litter; plantations; shoots; soil depth; soil water; stable isotopes; summer; tree growth; water requirement; water use efficiency
Abstract:
... Bioenergy production in poplar Short Rotation Coppice plantations (SRC) is strongly limited in drought prone areas due to the high crop water requirement. Appropriate scheduling of subsurface drip irrigation (SDI) could be a practice for ensuring adequate biomass production with reduced water inputs while maintaining high water-use efficiency. We tested SDI in a commercial SRC cultivated with the ...
Picea glauca; Populus; biodiversity; censuses; clearcutting; ecological function; forest resources; forests; hardwood; landscapes; mortality; soil water; tree growth; tree mortality; trees; Alberta
Abstract:
... Long-term sustainability of forest resources is in question given wide-spread use of conventional clear-cut silviculture. In response, variable retention (VR) harvest has been increasingly promoted as a landscape-based approach to enhance sustainability by maintaining biodiversity and other ecosystem functions in managed forests. Although the success of the VR approach depends on post-harvest stan ...
... Aphids can affect the growth or architecture of their host-trees, but rarely challenge their survival. Nonetheless, the woolly poplar aphid, Phloeomyzus passerinii, can kill healthy, mature poplars during outbreaks. Trees fail to open their buds and flush their leaves in the spring following a severe infestation. This insect develops on poplar trunks, where it induces galls which accumulate amino ...
... Stand dynamics in the boreal forest are driven by wildfire, and many think that emulating forest fire patterns during harvesting will adequately preserve biodiversity. We tested this hypothesis by examining saproxylic beetle assemblages from a chronosequence of aspen forest stands originating after wildfire or harvest across several age classes (1–2, 14–15, 28–29years old) as well as from mature ( ...
... Dedicated energy poplar plantations have a high biomass production potential in temperate regions, which may be further increased by improved management practices. The aim of this study was to investigate the effects of fertilization on short rotation forest poplar established on former arable land. We examined the effects on biomass production, net nutrient uptake in stems and branches, nutrient ...
... Poplar species are economically important sources of timber and bioenergy and they also have a valuable application in phytoremediation and in forest restoration programmes. The characterization of their responses in the face of environmental constraints is essential to ascertain their adaptation capacity. Quantification of chloroplast pigments and antioxidant compounds, nutrients and carbon isoto ...
... Poplars (Populus spp.) and Willows (Salix spp.) are predominantly grown in plantations on arable land in southern and central parts of Sweden to produce biomass for energy and other purposes. The present study aims at characterizing their present situation with special emphasis on the current extension of the cultivation, expected yield levels as well as on their effects on soil and water. The dat ...
... Site-appropriate tree species can provide greater ecological benefit by improving soil physicochemical properties and soil fertility and by increasing carbon sequestration. However, inter-species ranking derived from long-term, reliable data is still scarce. In this study, 13 tree species from >30yr of afforestation at long-term experimental forest plots were selected, and 24 parameters comprised ...
... Different species of Salicaceae are of interest for bioenergy production in Sweden. Surplus agricultural land is available and can be used for bioenergy plantations. Documentation of the effects of afforestation on soil properties is of importance for future recommendations on the choice of tree species and management measures.Hybrid aspen (Populus tremula×Populus tremuloides), poplar (Populus spp ...
death; community structure; Fagus; Carpinus; dead wood; Acer; coniferous forests; fungal communities; forest stands; trees; species diversity; timber production; Gymnospermae; Populus; conifers; fungi
Abstract:
... Commercial forestry increasingly aims at both optimizing timber production and maintaining species diversity. To maintain the diversity of the species-rich group of wood-inhabiting fungi, effective forest conservation concepts that include the enrichment of dead wood in commercial forests are required. However, which type of dead wood should be enriched in which type of forest stand (coniferous or ...
Alnus; Betula; European Union; Populus; Tilia; age structure; case studies; ecosystem services; even-aged stands; forest ecosystems; forest management; forest statistics; habitats; harvesting; homogenization; information management; issues and policy; land management; land ownership; land tenure; old-growth forests; privatization; silvicultural practices; spatial data; species diversity; sustainable forestry; time series analysis; world markets; Romania
Abstract:
... Historical forest management can heavily affect contemporary forest management and conservation. Yet, relatively little is known about century-long changes in forests, and that limits the understanding of how past management and land tenure affect current forestry practice and ecosystem conservation. Our goal here was to examine the relationship between historical forest management (as depicted by ...
Acer; Odocoileus virginianus; Picea abies; Populus; canopy; data collection; deer; forest trees; government agencies; monitoring; palatability; saplings; species recruitment; tree growth; Wisconsin
Abstract:
... Local, short- to medium-term studies make clear that white-tailed deer can greatly suppress tree growth and survival in palatable tree species. To assess how deer have broadly affected patterns of tree recruitment across northern Wisconsin, we analyzed recruitment success in 11 common trees species that vary in palatability across 13,105 USFS - FIA plots sampled between 1983 and 2013. We also exam ...
manganese; plantations; soil organic carbon; trees; Populus tremula; phosphorus; nutrients; land use; forests; hybrids; A horizons; planting; base saturation; energy; cation exchange capacity; copper; monitoring; calcium; arable soils; tree growth; nutritional status; nitrogen; wood; magnesium; pulp; B horizons; Northern European region
Abstract:
... The area of short-rotation forest (SRF) plantations with hybrid aspen (Populus tremula L.×P. tremuloides Michx.) for pulp and energy wood production in approximately 25-year rotation period has increased considerably during the last few decades in Northern Europe on previous agricultural lands. However, little is known about how this new land use will alter the chemical properties of soils in the ...
Populus; bioenergy; chronosequences; community structure; disturbed soils; environmental factors; equipment; forest management; forests; harvesting; logging; nitrogen content; overstory; plant communities; species diversity; trees; understory; variance; Great Lakes; Michigan
Abstract:
... Conservation of vegetation diversity has been integrated into forest management regimes as stands with high levels of diversity have been shown to possess enhanced ecological services and resilience to disturbance. Effects of intensified forest management and harvesting practices such as logging residue removals for bioenergy on vegetation diversity and community dynamics has been largely overlook ...
... Aspen mortality and overstory dieback have occurred at unusually high levels throughout Colorado and western North America over the past fifteen years. Findings from southwestern Colorado indicated dieback and mortality was clearly related to climate stress, coupled with disease and insect attack. To determine whether similar amounts and causes of mortality were occurring in other mountainous regi ...
... The rapid re-establishment of forests following large disturbances is being seen as one option to increase the contribution of forests to climate change mitigation. The temporary inclusion of pioneer trees as nurse crops on disturbed sites can facilitate the establishment of target tree species and may additionally benefit productivity and soil fertility. In this study we compared productivity and ...
humid zones; viability; rivers; ecoregions; seeds; shrubs; seedlings; highlands; semiarid zones; Populus trichocarpa; environmental factors; rain; spring; summer; trees; woodlands; heat sums; seed dispersal; British Columbia
Abstract:
... Within the Salicaceae, the poplar trees and willow shrubs display an r-selection reproductive strategy, with the production of vast numbers of seeds but these are tiny, viability lasts only a few weeks, and very few seedlings establish and mature to contribute to the woodland populations. The timing of seed release is consequently critical and for cottonwoods, riparian poplars, seed release has be ...
... The Nordic countries have a vision to become carbon neutral by 2050. One way to approach this vision is to cultivate and harvest fast-growing tree species as bioenergy.In three study parts, this paper investigated how hybrid aspen performs in the second generation of root suckers. The three studies investigated; (1) initial growth, (2) growth effects following three early thinning strategies, and ...
... Successful plant manipulation by herbivores requires a reconfiguration of the primary and secondary metabolisms of the host-plant. Water deficit is generally predicted to negatively affect the development of gall-inducing insects, by impairing their ability to remodel the primary metabolism of their host. We assessed whether host genotype could modulate water deficit effects on a gall-inducing aph ...
... We quantified the effects of different loads of forest logging residues on the microenvironment (soil temperature, soil volumetric water content, competing vegetation cover, and available nutrients) of planted hybrid poplars one year after planting, and assessed the corresponding seedling growth until the third growing season. In four experimental plantations across Quebec (Canada), we used a fact ...
Populus; boreal forests; clearcutting; community structure; conifers; ecosystems; herbaceous plants; pesticide application; planting; postharvest technology; salvage logging; shrubs; species diversity; stand structure; trees; understory; windthrow; winter
Abstract:
... Understory plants are critical to diversity and ecosystem function in boreal forests. Significant advances have been made in understanding understory vegetation dynamics following fire and clearcutting but the effect of stand-replacing windthrow on understory plant abundance, diversity, and composition, especially when followed by management interventions such as salvage logging and forest renewal ...
Populus; Vermivora chrysoptera; canopy; conifers; forest stands; habitats; hardwood; hardwood forests; males; nesting; nests; shrubs; survival rate; tree and stand measurements; trees
Abstract:
... Residual canopy trees as biological legacies in harvested aspen stands may mimic characteristics of naturally disturbed forests. We investigated the effects of legacy tree retention in young aspen (Populus spp.) forest stands on the quality of nesting habitat for the Golden-winged Warbler (Vermivora chrysoptera), a species of conservation concern that is dependent upon recently disturbed forest an ...
Populus; biomass production; breeding methods; canopy; genotype; leaf area index; least squares; leaves; photosynthesis; plantations; principal component analysis; respiratory rate; shade; shade tolerance
Abstract:
... Poplar (Populus sp.) canopy provides considerable shading in high-density plantations, imposing adverse impacts on crown characteristics relating to biomass production, such as leaf area index (LAI) and photosynthesis. However, it is yet unclear how the LAI, photosynthesis, and biomass production of poplars would respond to shading. In this study, the shading responses were investigated in three p ...
Populus; clones; forests; gene flow; genetic techniques and protocols; genetic variation; genotype; groundwater; microsatellite repeats; rivers; trees; water supply; water table; China
Abstract:
... To investigate the influence of groundwater and river dynamics on genetic diversity and clonal growth of Populus euphratica forests along the Tarim river system (Xinjiang Prov., China), we genotyped nine old stands in three study areas of various distance to the main river. Using seven microsatellite loci, 850 genotypes were found among 1701 analyzed trees, with 204 of these comprising at least tw ...
... Pruning is one of the silvicultural practices recommended for poplar plantations in order to produce clearwood. Common wisdom proposes pruning during the summer season, however little is known on trees’ physiological responses to pruning season and intensity. This study aimed at determining the effects of pruning season and intensity on growth and physiology of four hybrid poplar clones. Using 3ye ...
Populus; biomass production; carbon; forestry; genotype; growing season; isotopes; leaf area; leaves; nitrogen content; nutrients; plant density; plant growth; plantations; soil water content; stems; tree physiology; trees; water use efficiency
Abstract:
... Poplar coppice plantations for biomass production can be conducted under either short rotation coppice (SRC) or short rotation forestry (SRF) systems, depending on planting density and rotation length. It is likely that differences in planting density affect tree physiology through competition for resource acquisition, including light, water and nutrients. In this paper, we hypothesized that the e ...
interspecific variation; stomatal conductance; nitrogen; Abies; air temperature; leaf area; climate change; photosynthesis; Populus; nutrient use efficiency; roots; leaves; shoots
Abstract:
... To examine whether deciduous and evergreen tree species differ in their performance and plastic responses to elevated atmospheric CO2 and temperature, we investigated growth, leaf area ratio (LAR), specific root length (SRL), nitrogen uptake efficiency (NUpE) and nitrogen use efficiency (NUE) of Populus yunnanensis and Abies faxoniana grown in environment-controlled chambers. Our results showed th ...
Populus; biofuels; biomass production; climate; ecosystem services; energy; energy crops; growth models; hybrids; land cover; land use change; production technology; soil; spatial data; Minnesota; Wisconsin
Abstract:
... Short rotation woody crops such as Populus spp. and their hybrids (i.e., poplars) are a significant component of the total biofuels and bioenergy feedstock resource in the USA. Production of these dedicated energy crops may result in large-scale land conversion, which leads to questions about their economic, logistic, and ecologic feasibility. To address such concerns, we used available social (i. ...
Populus; antioxidant activity; ascorbate peroxidase; carboxylation; catechol oxidase; chloroplasts; drought; electron transfer; females; field capacity; leaves; males; peroxidase; photosynthesis; plasma membrane; protein content; proteins; reactive oxygen species; sugars; superoxide dismutase; water stress
Abstract:
... The effects of three watering regimes (100%, 50% and 25% of field capacity, FC) on photosynthetic traits and leaves’ self-protective systems were investigated in Populus cathayana Rehd. males and females. The results showed that drought (25% of FC) caused disorder in photosynthesis, increased the amounts of osmotically active substances (soluble sugars, proteins and proline), accumulation of react ...
Populus; Quercus; biomass; broadleaved evergreen forests; community structure; epiphytes; forest communities; grounds maintenance; habitats; hosts; lichens; mountains; primary forests; secondary forests; species diversity; trees; China
Abstract:
... Epiphytic macrolichen litterfall was collected over 3 years from primary evergreen broad-leaved forests (PF), Populus bonatii secondary forests (PBSF), middle-aged oak secondary forests (MOSF) and old-aged oak secondary forests (OOSF) of the Ailao Mountains in SW China. To assess changes in the epiphyte communities of the subtropical forests, we compared the differences in biomass, species diversi ...
interspecific variation; Coleoptera; linear models; cutting; forest stands; trees; species diversity; coarse woody debris; Populus; bark; forests; Sweden
Abstract:
... To preserve biodiversity in managed forest landscapes dead and living trees are retained at final cuttings. In the present study we evaluated the effect of these practices for saproxylic (wood-dependent) beetles inhabiting dead aspen trees (Populus tremulae). For saproxylic beetles, tree retention at final cuttings can be expected to be especially valuable for species adapted to sun-exposed dead w ...
tree growth; herbs; Pinus; Quercus; canopy; shrubs; Betula pendula subsp. mandshurica; ecological succession; Forsythia; Rosa xanthina f. hugonis; trees; forest management; species diversity; indigenous species; Populus; biogeography; forests
Abstract:
... It remains unclear whether or not creating gaps in planted forests can increase the plant species composition, structure, and biodiversity, and also whether it can be helpful for restoring planted forests (to a more natural state). Based on a comparison of species composition and structure among forest patches, small gaps (4–25m²), medium gaps (25–150m²) and large gaps (150–450m²), we found that ( ...
temporal variation; rivers; forest trees; age structure; riparian forests; geomorphology; vegetation cover; Salix; aerial photography; Tamarix; spatial variation; forest growth; flooded conditions; Populus; stand composition; groundwater; water table; Arizona
Abstract:
... Populus-Salix forests are a valued riparian vegetation type in western North America. These pioneer, obligate phreatophytes have declined on some rivers, raising conservation concerns and stimulating restoration plantings, but have increased on others. Understanding patterns and causes of forest change is essential for formulating conservation, restoration and management plans. Our goal was to ass ...
... Whole-stand models normally require data on initial stand basal area and dominant height. Dominant height measurements are time-consuming and often imprecise, compromising subsequent predictions. Poplar plantations provide a special case where basal area correlates with site index; a whole-stand model could thus be based on stand basal area. We report a static model constructed by the generalized ...
agroecosystems; grasslands; forest trees; landscapes; ecological succession; vegetation cover; habitats; floodplains; species diversity; forest plantations; Populus; land use; Carabidae; vegetation structure; forests; France
Abstract:
... Hybrid poplar plantations have become an important component of forest and agricultural landscapes in alluvial floodplains since poplars are among the fastest-growing trees in temperate regions. However, these habitats are thought to decrease biodiversity, including ground beetle diversity, as compared to other traditional land-uses such as grasslands and semi-natural forests. To evaluate the impa ...
Pinus; Quercus; forests; edible fungi; reforestation; host plants; trees; species diversity; forest ecosystems; forest habitats; Populus; forest communities; Mediterranean region
Abstract:
... The aim of this work was to study and describe fungal communities in different habitats in dry Mediterranean areas. The objective was to determine whether artificial reforestations can develop fungal communities as productive and diverse as those found in natural stands. The results could provide ecological and economical implications for forest management in marginal areas, in order to recover th ...
... To incorporate ruffed grouse (Bonasa umbellus) habitat planning in forest management, it is necessary for managers to understand factors contributing to grouse habitat use. Previous studies examining ruffed grouse drumming habitat documented relationships between drumming grouse and broad vegetation categories (e.g., northern hardwoods, young aspen [Populus spp.], oak [Quercus spp.]), but few stud ...
Populus; forest trees; ectomycorrhizae; tree growth; tree mortality; root inoculation; mycorrhizal fungi; Boletus edulis; plantation forestry; absorbents; plant-water relations; semiarid zones; dry environmental conditions; disease resistance; cankers (plants); dieback; China
Abstract:
... We evaluated the effects of direct use of an ectomycorrhiza fungal inoculum (Boletus edulis) mixed with indolebutyric acid (IBA), super-absorbent polymers (SAP) and organic compound fertilizer on the survival and growth of Populus hopeiensis saplings on a semiarid site in Inner Mongolia, China, during the first 5 years after planting, and the practical feasibility of using this inoculum mixture ov ...
drought tolerance; height; carbon; Robinia pseudoacacia; stable isotopes; interspecific variation; Populus; leaves; forest trees; plantation forestry; leaf area; ontogeny; Ziziphus jujuba; tree growth; nitrogen; water use efficiency; semiarid zones; Ulmus pumila; China
Abstract:
... On the Loess Plateau, China, several planted tree species such as Populus hopeinsis and Robinia pseudoacacia suffer occasional diebacks in the top shoots, reducing growth rates after maturation. However, this does not usually occur in other species, e.g., Ulmus pumila and Zizyphus jujuba. We compared stable carbon isotope ratios (δ ¹³C) as indicators of leaf water-use efficiency (WUE), leaf mass p ...
woodpeckers; Picidae; wild birds; forest health; indicator species; population size; species diversity; dead wood; nesting sites; wildlife habitats; forest habitats; habitat preferences; forest trees; correlation; temporal variation; Populus; bark beetles; Dendroctonus ponderosae; British Columbia
Abstract:
... Woodpeckers (family Picidae) merit specific monitoring and management efforts, both as keystone/facilitator species and as indicators of forest condition. Recent studies indicated that species richness of woodpeckers was correlated with richness of all forest birds, thus suggesting potential exists for management practices that can address needs of woodpeckers in particular and other forest birds ...
... Rotation periods control not only the above-ground growth but also the assimilate transfer to the root systems in Short Rotation Coppice (SRC). Since assimilates are needed for the nutrient supply of associated mycorrhizal fungi, their control by rotation period length seems most probable. One poplar (Populus nigra × maximowiczii cv. Max 4) and one willow clone (Salix viminalis clone 78-101) culti ...
brush control; correlation; hybrids; shrubs; tree age; pasture plants; nitrogen; soil properties; herbaceous plants; stand density; flora; species diversity; soil water; plant competition; forest plantations; Populus; land use; understory; France
Abstract:
... Much research effort is being devoted to developing forest management practices with limited impacts on biodiversity. While the impact of poplar Populus sp. plantations on biodiversity is relatively well-known at the landscape scale, the impact of alternative management practices at the plantation scale has received much less attention. Yet biodiversity is likely to be impacted by the choice of th ...
... Land-use and land cover strongly influence carbon (C) storage and distribution within ecosystems. We studied the effects of land-use on: (i) above- and belowground biomass C, (ii) soil organic C (SOC) in bulk soil, coarse- (250-2000μm), medium- (53-250μm) and fine-size fractions (<53μm), and (iii) ¹³C and ¹⁵N abundance in plant litter, bulk soil, coarse-, and medium- and fine-size fractions in the ...
broadleaved evergreen forests; boreal forests; rain forests; seasonal variation; stand composition; altitude; vapor pressure; shoots; interspecific variation; fertilizer application; Salix; forest stands; Populus; Betula; browsing; leaves; vegetation structure; mathematical models; forest trees; equations; leaf area; herbivores; stand density; species diversity; coarse woody debris; biomass; climatic factors; prediction; tree growth; old-growth forests; volume; nitrogen; age structure; Alces alces; Sweden; New Zealand
Abstract:
... Knowledge of plant-herbivore interactions is fundamental for understanding foraging patterns of herbivores and their effects on the ecosystem as well as the human use of natural resources. The nutrient resources available for plants may determine not only growth rate, but also the amounts of secondary compounds in the plant tissues. As a consequence, browsing pressure on plant communities by large ...
... Hybrid poplar plantations are increasing worldwide and are often accused of impoverishing bird communities. We conducted 124 bird point counts in a landscape where plantations, semi-natural forests and farmland occupied similar surface areas. As expected, birds occurred at higher densities in areas dominated by forests than dominated by plantations, mostly due to the scarcity of late-successional ...
... Despite the spatial significance of Canada's boreal forest, there is very little known about CH₄ and N₂O emissions from non-peatlands within it. The primary objective of this project was to study the atmosphere-soil exchange of CH₄ and N₂O at three sites in the boreal forest of central Saskatchewan. In the summers of 2006 and 2007, CH₄ and N₂O emissions were measured along transects in three diffe ...
lowland forests; ecological restoration; methodology; planting; direct seeding; afforestation; trees; Populus; Quercus; species diversity; tree growth; seedlings; seedling growth; mortality; vegetation structure; Mississippi
Abstract:
... Large-scale restoration of bottomland hardwood forests in the Lower Mississippi Alluvial Valley (USA) under federal incentive programs, begun in the 1990s, initially achieved mixed results. We report here on a comparison of four restoration techniques in terms of survival, accretion of vertical structure, and woody species diversity. The range of treatment intensity allowed us to compare native re ...
... Planting stock type and quality can have an important impact on early growth rates of plantations. The goal of this study was to evaluate early growth and root/shoot development of different planting materials in typical heavy clay soils of northwestern Quebec. Using one-year-old bareroot hybrid poplar dormant stock, four planting materials were compared: (1) regular bareroot stock, (2) rootstock ...
boreal forests; Abies balsamea; Picea glauca; stand composition; forest growth; density; interspecific variation; montane forests; Picea mariana; tree and stand measurements; forest stands; Pinus banksiana; Populus; fire severity; forest trees; botanical composition; wildfires; statistical analysis; prediction; tree growth; Betula papyrifera; forest regeneration; stand basal area; Ontario
Abstract:
... Postfire tree species compositions are predicted to be the same prior to fire according to the direct regeneration hypothesis (DRH). We studied 94 upland boreal forest stands between 5 and 18 years after fire in Ontario, Canada. Postfire species-specific regeneration density was positively related to prefire stand basal area for Pinus banksiana, Populus spp., Betula papyrifera and Picea mariana, b ...
... Salvage logging after natural disturbance has received increased scrutiny in recent years because of concerns over detrimental effects on tree regeneration and increased fine fuel levels. Most research on tree regeneration after salvage logging comes from fire-prone systems and is short-term in scope. Limited information is available on longer term responses to salvage logging after windstorms or ...
... Short rotation coppice culture systems are characterized by a high stool and shoot density, and by rotation durations between 2 and 3 years for species showing an extremely fast growth such as poplar. With the objective to study the long-term biomass production evolution and dynamic of such systems, a high-density plantation with 17 poplar (Populus) clones belonging to six parentages was establish ...
tree growth; hybrids; boreal forests; nitrogen; fertilizer application; fertilizers; clones; potassium; tree nutrition; plant response; Populus; phosphorus; measurement; Quebec
Abstract:
... In order to maximize growth and diagnose nutritional requirements of hybrid poplars (Populus spp.) grown in the boreal forest of western Quebec, the Diagnosis and Recommendation Integrated System (DRIS) was evaluated in conjunction with N:P ratios of trees fertilized at planting. Three hybrid poplar clones (747210; P. balsamifera x trichocarpa, 915005; P. balsamifera x maximowiczii, and 915319; P. ...
tree growth; forest trees; phytophagous insects; insecticides; branches; forest yields; costs and returns; branching; prices; dry matter accumulation; tree and stand measurements; Chrysomela scripta; clones; defoliation; Populus; stand basal area; tree mortality
Abstract:
... The effects of 8 years of cottonwood leaf beetle, Chrysomela scripta, defoliation on growth and economic value of four Populus clones (91x04-03, D105, Eugenei, and NM2) was investigated in a split-plot randomized complete block design with unprotected and insecticide-protected plots. After 8 years clones 91x04-03 and D105 had significantly greater survival than Eugenei or NM2. This difference in s ...
history; temporal variation; wildland fire management; Populus; age structure; dendrochronology; Picea mariana; mixed forests; frequency; forest stands; fire regime; Picea glauca; forest fires; Betula; climatic factors; conservation areas; Alaska
Abstract:
... We conducted this investigation in response to criticisms that the current Alaska Interagency Fire Management Plans are allowing too much of the landscape in interior Alaska to burn annually. To address this issue, we analyzed fire history patterns within the Yukon Flats National Wildlife Refuge, interior Alaska. We dated 40 fires on 27 landscape points within the refuge boundaries using standard ...
... Fertilization is required to maintain production of short rotation forestry plantations and an understanding of nutrient cycling processes is crucial in order to assess long-term sustainability of these systems. Fertilization can alter root biomass growth and turnover and the chemical and biochemical properties of the soil thus affecting soil carbon dynamics and soil quality. The present study was ...
Elaeagnus angustifolia; Populus; Ulmus pumila; trees; plant establishment; deficit irrigation; forest plantations; afforestation; tree mortality; tree growth; dry matter accumulation; root growth; soil degradation; microirrigation; furrow irrigation; roots; shoots; soil salinity; saline water; groundwater; water table; salt tolerance; Uzbekistan
Abstract:
... Degraded land within the irrigated areas of the Aral Sea Basin is characterized by high soil salinity, shallow saline groundwater (GW), low irrigation water availability and thus is often unsuitable for crop cultivation. Afforestation is one option for mitigating such degraded land but to be successful it requires the selection of appropriate tree species and irrigation techniques for tree establi ...
... Fast-growing trees such as hybrid poplars (Populus) have the potential to decrease rotation length (time to harvest) and thus produce wood products more quickly from smaller areas of land. Several forest companies in Quebec currently plant hybrid poplar on formerly logged forest sites, rather than on agricultural land as is more common elsewhere. The forest sites often have acidic soils, and lime ...
Populus; agricultural land; analysis of variance; clones; field experimentation; forests; hybrids; trees; variance; Finland
Abstract:
... Clonal repeatabilities, stability parameters and clone–site interactions for height and basal diameter were investigated in 3- and 4-year-old trees in four hybrid aspen clonal trials in southern Finland. The four field trials consisted of 24 aspen hybrid clones (Populus tremula×Populus tremuloides) and one P. tremula clone. There were differences in height and diameter growth among the trials on a ...
... The utility of a portable chlorophyll meter (SPAD-502, Minolta Camera Co. Ltd., Japan) for rapidly and nondestructively assessing foliar N status of hardwood species was evaluated in two experiments. In experiment one (established near Raleigh, North Carolina), 0, 56, 168, or 336 kg N/ha (ammonium nitrate) was applied in June 1998 to sycamore (Platanus occidentalis L.), sweetgum (Liquidambar styra ...
... There are large amounts of clear-cuts and secondary forests in Northeast China. In order to preserve habitats of biodiversity and decrease ecological disasters, it now becomes urgent to restore them to the climax. An adapted forest dynamics model is used to simulate the change in tree species composition, density, and stem productivity of forests regenerating from clear-cuts of the mixed-broadleav ...
... The aim of this work was to study mating systems in the genus Populus by recording flowering phenology and assessing the frequency of intra- and interspecific mating events using PCR based DNA markers in a range of poplar species growing in Edinburgh in the Royal Botanic Garden and the neighbouring Inverleith Park. The paternity of seedlings from the following three female poplars was studied P. n ...
... We studied young riparian cottonwoods (Populus spp.) and associated woody plants along Soda Butte Creek and the Lamar River in northeastern Yellowstone National Park (YNP) to examine the potential influence of wolf/elk interactions upon plant growth. After a peri od of approximately 70 years without wolves in YNP, they were reintroduced in the winter of 1995–1996. When we compared woody plant heig ...