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MV Naturraeume WFS

Informationen der staatlichen Umweltverwaltung Mecklenburg-Vorpommern: Die naturräumliche Gliederung als Themenbereich im Kartenportal Umwelt M-V besteht aus folgenden hierarchischen Ebenen - Landschaftszonen - Großlandschaften - Landschaftseinheiten - Naturräume Die der Digitalisierung zugrundeliegende Fassung der naturräumliche Gliederung für Mecklenburg-Vorpommern wurde für den terrestrischen und marinen Bereich getrennt erarbeitet (vgl. Quellen) und im Jahr 2001 im Auftrag des LUNG durch die Firma Umweltplan zusammengeführt und an die Landesgrenzen und Küstenlinien der ATKIS-Basis-DLM (1. Realisierungsstufe) angepasst. Die Einzelthemen dieses Bereiches sind auch als WMS Naturräume verfügbar.

Effects of nurse tree species on growth, environment and physiology of underplanted Toona ciliata (F. Muell.)

Das Projekt "Effects of nurse tree species on growth, environment and physiology of underplanted Toona ciliata (F. Muell.)" wird vom Umweltbundesamt gefördert und von Universität Freiburg, Waldbau-Institut durchgeführt. Toona ciliata (Australian red cedar) is highly valued for veneer and furniture production and endangered in its natural ecosystems due to exploitation. This work aims to improve the availability of this wood on the market and help reduce pressure on the species in its native environment. An afforestation project cultivating Toona ciliata was introduced to the study site in Misiones, Argentina. The local cultivation faces losses caused by drought and frost, because T. ciliata requires overstory protection when young. Consequently, Grevillea robusta, Pinus elliottii x Pinus caribaea, and Pinus taeda, nurse tree species which also produce sought-after wood were chosen to provide protection. One-year-old T. ciliata seedlings were planted underneath each of the six-year-old nurse species. An inventory after one year indicated that both survival and height increment were highest underneath G. robusta and lowest underneath P. elliottii x P. caribaea. In this study I am examining possible facilitation and competition mechanisms between the overstory and understory T. ciliata. Extensive empirical data collected over the course of 3 years will be utilized to project potential growth scenarios for several rotations using a computer based forest growth model.

Water consumption and carbon capture by trees of an evergreen and a dry forest in the Andes of South Ecuador as functional indicators of slow environmental changes

Das Projekt "Water consumption and carbon capture by trees of an evergreen and a dry forest in the Andes of South Ecuador as functional indicators of slow environmental changes" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Biologie, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Pflanzenphysiologie durchgeführt. This transfer project contributes to the development of a multifactorial indicator prototype for global change effects. It uses water and carbon relations of trees as primary functional indicators of subtle environmental changes which cannot be directly observed. Acquisition of carbon by a tree and its concomitant water loss by transpiration is coupled as water use efficiency (WUE), which as a parameter integrating two ecophysiological processes should display a high sensitivity to ambiental conditions. The project is based on a new model allowing computation of the entire crown. Parameterization of the model is by data of leaf gas exchange, total water loss, and structural data of the crown. Total water consumption will be determined either by stem flow monitoring or by the D2O injection method. Net carbon gain by the entire crown can be calculated from a crown-specific WUE. The described measurements will be supplemented by data on stem growth, phenology (longevity of leaves and foliage dynamics), long-term water relations (13C discrimination data) and tree hydrology (natural abundance of deuterium). To extend the indicator from the single tree scale to a wider area, project C5 will collaborate with project C6 which will investigate WUE using multispectral satellite and airborne data. For calibration transfer functions to remotely sensed data must be developed. Since Eddie covariance analysis cannot be used, project C6 will measure atmospheric dynamics of heat and water vapour above the canopy of an assemblage of such trees by scintillometry. These measurements shall be calibrated by C5. Of all trees on the study plots total transpiration will be measured and correlated with simultaneously recorded scintillometer data. Thus projects C5 and C6 will use the same plots and trees. Using the calibrated scintillometer data, project C6 will up-scale the functional indicator WUE to the landscape level. Because of their general applicability, functional indicators like WUE are especially useful for modelling approaches.

Einfluss von Dürre auf das Waldsterben in Europa und Westkanada (Water03 - IDDEC)

Das Projekt "Einfluss von Dürre auf das Waldsterben in Europa und Westkanada (Water03 - IDDEC)" wird vom Umweltbundesamt gefördert und von Technische Universität München, Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt, Fachgebiet für Ökoklimatologie durchgeführt. While many forests and woodlands may be at increasing risk of climate-induced dieback, significant knowledge gaps remain in our understanding of the causes of climate-induced tree mortality. Recent publications underscore the critical importance of understanding the mechanisms that trigger plant mortality (Adams et al., 2009), particularly regarding features and traits that could be used as physiological indicators of tree death (McDowell et al., 2008). Alterations in wood formation and structure often occur prior to visual symptoms of crown decline. Thus, physiological, morphological, and anatomical traits related to xylem ('water-conducting pipes') may provide early-warning signals of drought-induced dieback. A better mechanistic understanding of drought-induced forest dieback would improve our ability to predict tree mortality and future changes in forest composition and coverage. The project aims at studying how drought episodes promote dieback via changes in xylem structure. Different genotypes of aspen (parkland region and the southern boundary of the boreal forest in western Canada), oak (Southern Europe) and pine (experiment) will be studied along gradients of moisture availability. Xylem-related traits that will be measured include ring-width, number of missing rings, quantitative wood anatomical structures (diameter and frequency of vessels/ tracheids, inter-vessel pit structure) as well as cavitation resistance, hydraulic conductivity, and water potentials.

Can the resistance and resilience of trees to drought be increased through thinning to adapt forests to climate change?

Das Projekt "Can the resistance and resilience of trees to drought be increased through thinning to adapt forests to climate change?" wird vom Umweltbundesamt gefördert und von Universität Freiburg, Waldbau-Institut durchgeführt. Recent and predicted increases in extremely dry and hot summers emphasise the need for silvicultural approaches to increase the drought tolerance of existing forests in the short-term, before adaptation through species changes may be possible. We aim to investigate whether resistance during droughts, as well as the recovery following drought events (resilience), can be increased by allocating more growing space to individual trees through thinning. Thinning increases access of promoted trees to soil stored water, as long as this is available. However, these trees may also be disadvantaged through a higher transpirational surface, or the increased neighbourhood competition by ground vegetation. To assess whether trees with different growing space differ in drought tolerance, tree discs and cores from thinning experiments of Pinus sylvestris and Pseudotsuga menziesii stands will be used to examine transpirational stress and growth reduction during previous droughts as well as their subsequent recovery. Dendroecology and stable isotopes of carbon and oxygen in tree-rings will be used to quantify how assimilation rate and stomatal conductance were altered through thinning. The results will provide crucial information for the development of short-term silvicultural adaptation strategies to adapt forest ecosystems to climate change. In addition, this study will improve our understanding of the relationship between resistance and resilience of trees in relation to extreme stress events.

The effect of potassium and calcium on wood formation and xylem/phloem physology

Das Projekt "The effect of potassium and calcium on wood formation and xylem/phloem physology" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Department für Biologie, Zentrum Holzwirtschaft, Ordinariat für Holzbiologie und Institut für Holztechnologie und Holzbiologie des Johann Heinrich von Thünen-Institut, Bundesforschungsinstitut für Ländliche Räume, Wald und Fischerei durchgeführt. Ions play a fundamental role in the physiology of cambial growth. To gain better knowledge about the role of K, Ca and P in wood formation, we intend to focus on plants grown under different K, Ca and P supply as well as on transgenic plants with modified ion transporter expression produced by P5 and/or P3. Two approaches will be applied on all differently treated plants in this project. First, structural and ultrastructural analysis of stem tissues (phloem, cambium, xylem) will be carried out throughout all seasons by image analysis and high resolution TEM. In order to correlate structural changes to biochemical variations, a second approach deals with the following analysis in all tissues: Seasonal changes of K, Ca and P will be measured by EDXA, whereas K and Ca will also be determined quantitatively by atomic absorption spectrometry. By generating antibodies against different potassium transporters we further will show their distribution in poplar stem tissues throughout all seasons by fluorescence and transmission electron microscopy. In order to correlate changes in ion content to sugar concentrations, seasonal variations of different sugars as well as starch will be determined enzymatically. To measure changes in the chemical composition of cell walls, FTIR-spectroscopy will be used to quantitatively detect a range of functional groups in the cell wall.

The Carbon Sink Strength of Beech in a Changing Environment: Experimental Risk Assessment of Mitigation by Chronic Ozone Impact (CASIROZ)

Das Projekt "The Carbon Sink Strength of Beech in a Changing Environment: Experimental Risk Assessment of Mitigation by Chronic Ozone Impact (CASIROZ)" wird vom Umweltbundesamt gefördert und von Technische Universität München, Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt, Department Ökologie, Lehrstuhl für Ökophysiologie der Pflanzen durchgeführt. The project aims at clarifying the vulnerability of adult beech trees, growing under Central-European stand conditions, to the tropospheric, chronic ozone (O3) impact. O3 as being part of 'Global Change may constrain the carbon sink strength of trees under the expected atmospheric CO2 enrichment. A novel 'Free-Air Canopy O3 Exposure' system, creating an experimentally enhanced O3regime within the canopy (relative to 'control' trees in unchanged air), is employed for analyzing O3-induced responses that are relevant for the carbon balance and CO2 demand of the trees. For relating tree performance to effective O3 doses rather than O3 exposure, the O3 flux concept into leaves will be examined and validated against AOT40. Response patterns will be assessed, integrating the cell, organ and whole-tree level, while making use of molecular, biochemical and ecophysiological methodologies. In addition, branch cuvette fumigations and exposure of young beech plants inside the stand canopy will validate the ecological significance of former O3 studies in phytotrons, open-top chambers or on single branches in tree crowns. Evidence will be incorporated into mechanistic modeling for scaling to the stand level and quantifying O3 impact for 'Global Change' scenarios. This process-oriented risk assessment will guide environmental policy making. The objective is to assess the vulnerability of adult beech trees to the ground level, chronic O3 impact by employing a novel 'Free-Air Canopy O3 Exposure' system that experimentally enhances the O3 exposure within the forest canopy. Ozone is viewed as one component in 'Global Change' scenarios in that it may mitigate the supposed increases in productivity under elevated CO2 conditions by reducing the carbon sink strength of trees and forests. This issue is regarded relevant, as recent experiments suggest such an antagonistic interaction between ozone and CO2 in plant performance. Prognoses indicate further increase in chronic, ground level O3 exposure to occur during the 21st century across the northern hemisphere, and deficits in knowledge are still significant, in particular regarding the responsiveness of advanced tree age and current O3 threshold definitions like AOT40. (...) The major outcome of this study will be the elaboration of a database needed for the management of trees and stands under the chronic, enhanced ground level O3 regimes. This includes mechanistic knowledge regarding threshold definitions of O3 flux (uptake) rather than exposure. The most important relevance of the elaborated results will be for the UNECE Level II and III concepts about 'Critical Levels for Ozone and the UNECE ICP-Forests. In particular, impacts on practical development strategies will be (1) evaluation tools to assess modifications of the CO2 sink strength of forests due to additional impacts, in the present case ozone (cf. Kyoto protocols) and (2) quantification of factors modifying the O3 effect on adult beech forest trees, Etc.

D 1.2: Reducing alternation and production of off-season fruits in Lychee, Longan and Mango

Das Projekt "D 1.2: Reducing alternation and production of off-season fruits in Lychee, Longan and Mango" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Kulturpflanzenwissenschaften (340), Fachgebiet Düngung und Bodenstoffhaushalt (340i) durchgeführt. The aim and vision of sub-project D1.2 was and is to encourage hillside farmers to plant erosion resistant fruit trees instead of erosion susceptible annual plants. For that reason, experiments to overcome the irregular bearing behaviour of the three most common fruit tree species in Northern Thailand (Litchi, Longan and Mango) from the first SFB period will be continued in order to make their planting more attractive to the farmers. Considerable progress has been made in D1 during the past 3 years to induce flowers and fruit in Longan trees by the application of KClO3 . With this technique, it was not only possible to induce year around flowers and fruit (off season fruit) but also to overcome the generally rather irregular fruiting behaviour of these trees. A similar technique is now being developed for Mango by using an inhibitor of the bio-synthesis of the plant hormone gibberellin. Only Litchi still resist this kind of manipulation by an 'off season technique' (OST). Great effort will therefore be devoted establishing a similar system for this species as well. Reliably, this can only be done by gaining a much better knowledge of the - most certainly hormonal - regulatory system that governs flower induction in trees. Investigations into the hormonal changes taking place during natural and induced flower induction is, therefore, one of the central objectives in this sub-project, with the goal to better understand the process of flower induction. Until now most of the progress in this area is entirely empirical in nature and a more specific manipulation therefore difficult. While the ability to produce off season fruit all year around and under various weather conditions has brought about a great number of new possibilities, new challenges will still be faced with regard to these methods. These circumstances will affect the whole production chain from the orchard to the market and consumer. In order to better investigate and understand these new situations, a large model experiment with Mango will be set up and problems like tree pruning, water and nutrient demand, phytopathological problems, demand on work force, fruit processing and drying etc. will be investigated by the interdisciplinary co-operation of 8 sub-projects within the SFB. The results obtained during these investigations will be shared with hillside farmers enabling them to take advantage of these new possibilities, which will provide for more reliable yields and allow them to market fruit year around. In general, these new opportunities should encourage farmers to plant more trees and thus reduce erosion. However, to make this system not only reliable and economic but also ecologically and socially beneficial to the society all potential benefits as well as risks have to be evaluated carefully from all different aspects.

Seasonal regulation of ion- and metabolite transport between poplar shoot tissues

Das Projekt "Seasonal regulation of ion- and metabolite transport between poplar shoot tissues" wird vom Umweltbundesamt gefördert und von Universität Würzburg, Julius-von-Sachs-Institut für Biowissenschaften mit Botanischem Garten, Lehrstuhl für Botanik I Molekulare Pflanzenphysiologie und Biophysik durchgeführt. We intend to investigate the molecular mechanisms of mineral nutrient dependent poplar physiology with special focus on potassium. This will be accomplished using two different approaches. 1. Molecular biology: We will study the regulation of ion channels and transporters by different environmental conditions, such as the effect of nutrition, salt, hormonal action, cold and drought during wood production and the dormancy-growth transitions. Phenotype analysis of transporter sense/antisense plants will be used to gain insights into the role of the transporters in tree physiology. On the basis of a laser-micro-dissection system, we will be able to prepare cDNA of distinct cell types and generate subtractive cDNAs to determine genes, specific for the differentiation of vessels and bast fibers. 2. Electrophysiological investigations: We will compare the functional properties of the transporters. Ion-fluxes and transporters, involved in cambial activation will be characterized in vivo and in vitro. The response to changes in e.g. the extracellular medium in vitro, will provide a measure for the regulation of ion transport by apoplastic factors in vivo. Based on this data sets we should be able to establish a model on the seasonal fluxes of potassium in relation to the transporter properties and dynamics in the context of tree physiology in general and xylogenesis in particular.

Multi-proxy tree-ring analysis of conifer trees disturbed by insect outbreaks

Das Projekt "Multi-proxy tree-ring analysis of conifer trees disturbed by insect outbreaks" wird vom Umweltbundesamt gefördert und von University of British Columbia, Faculty of Forestry, Department of Forest Resources Management Vancouver durchgeführt. Insect outbreaks are a major disturbance influencing forest dynamics in many ecosystems and can affect forest productivity worldwide. Reconstruction of insect outbreak history is fundamental to forest management. While the action of cambium feeders on trees leads to the formation of scars, that of defoliators is observable via growth suppression in tree rings. The occurrence of past insect attacks can thus be inferred from such tree-ring signatures. However, it necessitates an accurate dating of events, with high temporal resolution, as well as their correct attribution to the right disturbance agent. Fire also leaves scars on trees that can occur on cross-sectional disks where insect scars are already present, thus making them difficult to distinguish. Furthermore, insect-elicited reductions in radial growth may not be clearly visible on samples, and the radial growth response to defoliation often bears a lag of one or more years. This project tackles these issues directly by proposing a multi-proxy approach aiming at improving tree-ring reconstructions of insect outbreaks. Tree rings will be investigated to study radial variations of tree-ring width, wood anatomy, wood density, and wood chemistry. While dendrochronologists have long relied on tree-ring width variations to track the signal induced by climate, geomorphic and ecological processes, they have scarcely exploited the potential of other proxies and rarely used them in combination. The most advanced studies that have embraced these possibilities are owed to dendroclimatologists. The core of this research therefore lies in the use of multiple wood traits to provide answers to the above mentioned dendroecological questions. Two conifer tree species from British Columbia and their respective pests are within the scope of this study: the mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins), a cambium feeder, on lodgepole pine (Pinus contorta Douglas), and the western spruce budworm (WSBW, Choristoneura occidentalis Freeman), a defoliator, on Douglas-fir (Pseudotsuga menziesii Franco). It is hypothesized that insect outbreak disturbance in the form of bark beetle or defoliation events results in abrupt significant structural differences between the wood formed prior to and after the insect attack. Based on pioneering tree-ring research on insect outbreaks, there are great prospects that the variations of wood traits be proven useful for differentiating MPB scars from fire scars and for identifying WSBW defoliation events, possibly with higher temporal resolution. The study of multiple wood traits (proxies) will help gain an understanding of the influence of insect outbreak disturbance on wood formation and tree physiological processes, a prerequisite for improving the detection and dating of events in tree-ring series. (...)

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