scholarly journals Dynamik dichter, gleichförmiger Gebirgsfichtenwälder

2013 ◽  
Vol 164 (2) ◽  
pp. 37-46 ◽  
Author(s):  
Peter Bebi ◽  
Frank Krumm ◽  
Urs-Beat Brändli ◽  
Andreas Zingg
Keyword(s):  
Basal Area ◽  
Field Studies ◽  
National Forest Inventory ◽  
Active Management ◽  
Small Scale ◽  
Mountain Forests ◽  
Damage Potential ◽  
Research Activities ◽  
Federal Institute

Dynamics of dense, uniform spruce-dominated mountain forests Dense, uniform stands have increased in spruce-dominated mountain forests during the last century and often cause silvicultural problems. During recent years, different research activities at Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) have addressed the development of such mountain forests with or without active management. For this, plots of the Swiss National Forest Inventory (NFI) between 1983/1985 and 2004/2006 have been analysed, dendroecological methods have been used to investigate competition and selfthinning processes and a reassessment of WSL long-term investigation plots has been conducted. NFI plots of stands which have already been dense during the first inventory period generally showed increasing basal area, stagnating stem numbers, strongly increasing amounts of deadwood and slightly increasing regeneration levels, both in managed and in unmanaged stands. Dendroecological field studies confirm that trees in the generally about 80 to 150 years old stands were strongly affected by competition-induced self-thinning and subsequent small-scale mortality processes few decades after stand initiation already. WSL long-term investigation plots generally confirm this dominance of relatively small-scale processes, but also show potential for silvicultural interventions, especially in early stages of self-thinning. According to the guidelines for silvicultural intervention in forests with protective functions (NAIS), an active management of later self-thinning stages with already short crowns and higher mortality should focus on stands where risks have to be considered as too high, based on hazard and damage potential and the size of the dense, uniform stands.

scholarly journals Huftiere und Verjüngung im Gebirgswald: eine Geschichte mit vielen Variablen und noch mehr Interaktionen | Ungulates and Tree Regeneration in Mountain Forests: an Issue with many Variables and even more Interactions

2000 ◽  
Vol 151 (4) ◽  
pp. 99-106 ◽  
Author(s):  
Josef Senn
Keyword(s):  
Tree Regeneration ◽  
Small Scale ◽  
Mountain Forest ◽  
Forest Trees ◽  
Mountain Forests ◽  
Wild Ungulates ◽  
Site Factors ◽  
The Past

After excessive cutting in Swiss mountain forests and extirpation of most of the wildlife during the past centuries, efficient forestry and hunting laws allowed a wide regeneration of the forests and a rapid increase of ungulate populations in the present century. As a consequence, the impacts of ungulates on the vegetation became obvious. Regeneration of forest trees, however, is influenced not only by ungulates, but by a number of physical site factors and biotic impacts. As these impacts and their interactions vary extensively, regeneration is neither spatially nor temporally constant. Most of the presently used tree-regeneration methods, however, assume constant conditions, which renders a proper evaluation of tree regeneration in mountain forests and the role of ungulates impossible. Furthermore, the effect of this variation on forest development and forest functions is unknown with regard to the long term. While society requires a multipurpose mountain forest, structured at a small scale, wild ungulates use their habitat at a larger scale. This often leads to conflicts. Consequently,solutions including different scales are necessary. A lack of knowledge will, therefore, have to be met by research making data available to the practice as well as through coordinated investigations and experiments.

Thinning and site quality influence aboveground tree carbon stocks in yellow-poplar forests of the southern Appalachians

2010 ◽  
Vol 40 (4) ◽  
pp. 659-667 ◽  
Author(s):  
Tara L. Keyser
Keyword(s):  
Basal Area ◽  
Active Management ◽  
Site Quality ◽  
Southern Appalachians ◽  
Growth Data ◽  
Yellow Poplar ◽  
Stand Management ◽  
C Storage ◽  
Trade Offs

Little information exists regarding the effects of intermediate stand management activities (e.g., thinning) on C storage. This lack of information has created uncertainty regarding trade-offs between the benefits observed following thinning and C storage. Using long-term growth data, this study examines the effect of thinning on C storage while controlling for the effects of site quality in yellow-poplar ( Liriodendron tulipifera L.) forests throughout the southern Appalachian Mountains. In 1960, one hundred and eighteen 0.1 ha plots were established in yellow-poplar forests throughout the southern Appalachians and subsequently thinned to a randomly assigned residual basal area (RBA) (square metres per hectare). Carbon storage increased through time across all levels of RBA. RBA had a long-term effect on C storage with greater C storage occurring at greater RBA. On average-quality sites, thinning to 30 m2·ha–1 stored 84% more C than thinning to 10 m2·ha–1. At no time did plots with progressively lower RBA store more C than plots with progressively higher RBA. The results from this study provide information about the effects of intermediate silvicultural disturbance on C dynamics of the aboveground live tree pool in a complex landscape and may be used to inform decisions regarding trade-offs between active management and C storage.

Structural changes in protected forests in Sweden: implications for conservation functionality

2015 ◽  
Vol 45 (9) ◽  
pp. 1215-1224 ◽  
Author(s):  
Per-Ola Hedwall ◽  
Grzegorz Mikusiński
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Structural Changes ◽  
Fire Suppression ◽  
National Forest Inventory ◽  
Active Management ◽  
Tree Species Composition ◽  
Small Areas ◽  
Large Trees

Protected forest areas (PFAs) are key features of biodiversity conservation, and knowledge about long-term development is crucial in evaluating their efficiency and management needs. Longitudinal data on forest structure in PFAs is uncommon and often from small areas. Here we use data from the Swedish National Forest Inventory to study changes in more than 750 000 ha of PFAs over 60 years. Structures important for biodiversity, e.g., number of large trees and the volume of hard deadwood, including both standing and down wood, have more than doubled. The initial volume of deadwood, however, was very low. The overall tree species composition was stable over time, and only among the largest trees were there indications of a shift towards the late successional Norway spruce (Picea abies (L.) Karst.). Deadwood increased independent of species, size of wood, and site characteristics. This increase was positively related to the volume of living trees and forest age. We conclude that Swedish PFAs, in the absence of active management and under fire suppression at the landscape scale, develop structural components that are crucial for conservation of biodiversity. However, although tree species composition appears stable, present disturbance regimes in the PFAs are considerably different from those in naturally dynamic forests, which may have implications for long-term biodiversity maintenance.

scholarly journals Stand-level mortality models for Nordic boreal forests

Silva Fennica ◽  
2020 ◽  
Vol 54 (5) ◽  
Author(s):  
Jouni Siipilehto ◽  
Micky Allen ◽  
Urban Nilsson ◽  
Andreas Brunner ◽  
Saija Huuskonen ◽  
...  
Keyword(s):  
Boreal Forests ◽  
Basal Area ◽  
Stand Density ◽  
Logistic Function ◽  
National Forest Inventory ◽  
Growth And Yield ◽  
Stand Age ◽  
Probability Of Survival ◽  
Mortality Models

New mortality models were developed for the purpose of improving long-term growth and yield simulations in Finland, Norway, and Sweden and were based on permanent national forest inventory plots from Sweden and Norway. Mortality was modelled in two steps. The first model predicts the probability of survival, while the second model predicts the proportion of basal area in surviving trees for plots where mortality has occurred. In both models, the logistic function was used. The models incorporate the variation in prediction period length and in plot size. Validation of both models indicated unbiased mortality rates with respect to various stand characteristics such as stand density, average tree diameter, stand age, and the proportion of different tree species, Scots pine ( L.), Norway spruce ( (L.) Karst.), and broadleaves. When testing against an independent dataset of unmanaged spruce-dominated stands in Finland, the models provided unbiased prediction with respect to stand age.Pinus sylvestrisPicea abies

Using laboratory incubations to predict the fate of pharmaceuticals in aquatic ecosystems

2018 ◽  
Vol 15 (8) ◽  
pp. 463 ◽  
Author(s):  
Johan Fahlman ◽  
Jerker Fick ◽  
Jan Karlsson ◽  
Micael Jonsson ◽  
Tomas Brodin ◽  
...  
Keyword(s):  
Field Study ◽  
Environmental Conditions ◽  
Aquatic Ecosystems ◽  
Laboratory Experiments ◽  
Field Studies ◽  
Small Scale ◽  
Removal Rates ◽  
Laboratory Conditions ◽  
Dissipation Rates

Environmental contextEnvironmental persistence of excreted pharmaceuticals in aquatic ecosystems is usually predicted using small-scale laboratory experiments assumed to simulate natural conditions. We studied five pharmaceuticals comparing their removal rates from water under laboratory conditions and under natural environmental conditions existing in a large pond. We found that the laboratory conditions did not fully capture the complexity within the pond, which led to different removal rates in the two systems. AbstractEnvironmental persistence is a key property when evaluating risks with excreted pharmaceuticals in aquatic ecosystems. Such persistence is typically predicted using small-scale laboratory incubations, but the variation in aquatic environments and scarcity of field studies to verify laboratory-based persistence estimates create uncertainties around the predictive power of these incubations. In this study we: (1) assess the persistence of five pharmaceuticals (diclofenac, diphenhydramine, hydroxyzine, trimethoprim and oxazepam) in laboratory experiments under different environmental conditions; and (2) use a three-month-long field study in an aquatic ecosystem to verify the laboratory-based persistence estimates. In our laboratory assays, we found that water temperature (TEMP), concentrations of organic solutes (TOC), presence of sediment (SED), and solar radiation (SOL) individually affected dissipation rates. Moreover, we identified rarely studied interaction effects between the treatments (i.e. SOL×SED and TEMP×SOL), which affected the persistence of the studied drugs. Half-lives obtained from the laboratory assays largely explained the dissipation rates during the first week of the field study. However, none of the applied models could accurately predict the long-term dissipation rates (month time-scale) from the water column. For example, the studied antibioticum (trimethoprim) and the anti-anxiety drug (oxazepam) remained at detectable levels in the aquatic environment long after (~150 days) our laboratory based models predicted complete dissipation. We conclude that small-scale laboratory incubations seem sufficient to approximate the short-term (i.e. within a week) dissipation rate of drugs in aquatic ecosystems. However, this simplistic approach does not capture interacting environmental processes that preserve a fraction of the dissolved pharmaceuticals for months in natural water bodies.

scholarly journals AMETTA LEARNING MODEL DESIGN (ACTIVE, FUN AND WITHOUT PRESSURE)

2021 ◽  
Vol 27 (2) ◽  
Author(s):  
Yenni Hasnah ◽  
Pirman Ginting ◽  
Ratna Sari Dewi
Keyword(s):  
Data Analysis ◽  
Large Scale ◽  
Field Studies ◽  
Learning Model ◽  
Small Scale ◽  
Model Design ◽  
Brain Gym ◽  
Research Activities ◽  
Learning Success ◽  
Collection Data

This study aims to design a learning model that is active, fun, and without pressure called the AMETTA learning model. Research activities are carried out by applying a mixed research method that combines qualitative and quantitative data analysis with the stages of research activities, including literature studies, field studies, data collection, data analysis, and designing learning models. The results show that the AMETTA learning model design is suitable for use as a learning model to improve learning quality based on <em>experts' feedback</em>. This feasibility is also supported by an increase in the percentage of students' learning success, which is significant between the initial and final tests on small-scale (34.28%) and large-scale (38.47%) trials that this learning model is useful for implementation in learning activities. The AMETTA learning model meant is active, fun, and stress-free learning through the application of varied and exciting learning methods and media and the implementation of the <em>Brain Gym</em> in the learning process.

SELECTION WORK TO IMPROVE PRODUCTIVE AND BREWING QUALITIES OF SPRING BARLEY

1970 ◽  
pp. 38-40
Author(s):  
О. V. Levakova ◽  
L. М. Eroshenko ◽  
А. N. Eroshenko
Keyword(s):  
Protein Content ◽  
Spring Barley ◽  
Humus Content ◽  
Stability Index ◽  
Field Studies ◽  
Climatic Conditions ◽  
Extract Content ◽  
Labile Phosphorus ◽  
Loam Soil

The article presents and analyzes data of competitive varietal testing of promising varieties and lines of spring barley for yield and brewing qualities. Field studies were conducted in 2014–2017 on dark gray forest heavy loam soil. Agrochemical parameters are total nitrogen – 0.24%, humus content in a layer of 0-40 cm (according to Tyurin) – 5.19%, hydrolysis nitrogen – 123.5 mg / kg, salt extract pH – 4.92 mg-eq / 100g; labile phosphorus - 34.6 mg / 100g, labile potassium – 20.0 mg / 100g. The forerunner is winter wheat. Meteorological conditions in the years of research differed from each other and from the average long-term value. Barley samples were assessed by the protein content in the grain (GOST 10846-91), extract content (GOST 12130-77), weight 1000 grains (GOST 10842-89). Ecological plasticity was determined by the method proposed by E.D. Nettevich, A.I. Morgunov and M.I. Maksimenko, stability index (Ľ) by A. A. Gryaznov, indicator of stability level (Puss) by E. D. Nettevich and A. I. Morgunov. The main measure for assessing quality indicators is protein content. Many other biochemical and technological features of grain depend on its level. The experimental data convincingly testify to the significant influence of the soil and climatic conditions on the yield and, especially, on the brewing qualities of barley in the conditions of the Central Region of the Nonchernozem Zone. According to the studied traits, new valuable varieties Nadezhny, Sir, Noble and selection lines 141 / 1-09 h 746, 23 / 1-10 h 784, distinguished by high adaptability and resistance to adverse environmental factors, have been identified.

EBS Behaviour Immediately After Repository Closure in a Clay Host Rock: The HE-E Experiment (Mont Terri URL)

2011 ◽  
Author(s):  
Irina Gaus ◽  
Klaus Wieczorek ◽  
Juan Carlos Mayor ◽  
Thomas Trick ◽  
Jose´-Luis Garcia` Sin˜eriz ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Host Rock ◽  
Large Scale ◽  
Process Models ◽  
Research Activities ◽  
Hydraulic Behaviour ◽  
Validation Experiment ◽  
Engineered Barrier ◽  
Mont Terri

The evolution of the engineered barrier system (EBS) of geological repositories for radioactive waste has been the subject of many research programmes during the last decade. The emphasis of the research activities was on the elaboration of a detailed understanding of the complex thermo-hydro-mechanical-chemical processes, which are expected to evolve in the early post closure period in the near field. It is important to understand the coupled THM-C processes and their evolution occurring in the EBS during the early post-closure phase so it can be confirmed that the safety functions will be fulfilled. Especially, it needs to be ensured that interactions during the resaturation phase (heat pulse, gas generation, non-uniform water uptake from the host rock) do not affect the performance of the EBS in terms of its safety-relevant parameters (e.g. swelling pressure, hydraulic conductivity, diffusivity). The 7th Framework PEBS project (Long Term Performance of Engineered Barrier Systems) aims at providing in depth process understanding for constraining the conceptual and parametric uncertainties in the context of long-term safety assessment. As part of the PEBS project a series of laboratory and URL experiments are envisaged to describe the EBS behaviour after repository closure when resaturation is taking place. In this paper the very early post-closure period is targeted when the EBS is subjected to high temperatures and unsaturated conditions with a low but increasing moisture content. So far the detailed thermo-hydraulic behaviour of a bentonite EBS in a clay host rock has not been evaluated at a large scale in response to temperatures of up to 140°C at the canister surface, produced by HLW (and spent fuel), as anticipated in some of the designs considered. Furthermore, earlier THM experiments have shown that upscaling of thermal conductivity and its dependency on water content and/or humidity from the laboratory scale to a field scale needs further attention. This early post-closure thermal behaviour will be elucidated by the HE-E experiment, a 1:2 scale heating experiment setup at the Mont Terri rock laboratory, that started in June 2011. It will characterise in detail the thermal conductivity at a large scale in both pure bentonite as well as a bentonite-sand mixture, and in the Opalinus Clay host rock. The HE-E experiment is especially designed as a model validation experiment at the large scale and a modelling programme was launched in parallel to the different experimental steps. Scoping calculations were run to help the experimental design and prediction exercises taking the final design into account are foreseen. Calibration and prediction/validation will follow making use of the obtained THM dataset. This benchmarking of THM process models and codes should enhance confidence in the predictive capability of the recently developed numerical tools. It is the ultimate aim to be able to extrapolate the key parameters that might influence the fulfilment of the safety functions defined for the long term steady state.

scholarly journals Rabies in Our Neighbourhood: Preparedness for an Emerging Infectious Disease

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 375
Author(s):  
Michael P. Ward ◽  
Victoria J. Brookes
Keyword(s):  
Infectious Disease ◽  
Southeast Asia ◽  
Field Studies ◽  
Emerging Infectious Disease ◽  
Disease Response ◽  
Canine Rabies ◽  
Research Activities ◽  
Potential Reservoir ◽  
Modelling Studies ◽  
Sociological Studies

Emerging infectious disease (EID) events have the potential to cause devastating impacts on human, animal and environmental health. A range of tools exist which can be applied to address EID event detection, preparedness and response. Here we use a case study of rabies in Southeast Asia and Oceania to illustrate, via nearly a decade of research activities, how such tools can be systematically integrated into a framework for EID preparedness. During the past three decades, canine rabies has spread to previously free areas of Southeast Asia, threatening the rabies-free status of countries such as Timor Leste, Papua New Guinea and Australia. The program of research to address rabies preparedness in the Oceanic region has included scanning and surveillance to define the emerging nature of canine rabies within the Southeast Asia region; field studies to collect information on potential reservoir species, their distribution and behaviour; participatory and sociological studies to identify priorities for disease response; and targeted risk assessment and disease modelling studies. Lessons learnt include the need to develop methods to collect data in remote regions, and the need to continuously evaluate and update requirements for preparedness in response to evolving drivers of emerging infectious disease.

Small-Scale Deliberation and Mass Democracy: A Systematic Review of the Spillover Effects of Deliberative Minipublics

2021 ◽  
pp. 003232172110072
Author(s):  
Ramon van der Does ◽  
Vincent Jacquet
Keyword(s):  
Systematic Review ◽  
Empirical Evidence ◽  
Empirical Research ◽  
Spillover Effects ◽  
Future Research ◽  
Small Scale ◽  
Long Term Effects ◽  
Current Crisis ◽  
Mass Democracy

Deliberative minipublics are popular tools to address the current crisis in democracy. However, it remains ambiguous to what degree these small-scale forums matter for mass democracy. In this study, we ask the question to what extent minipublics have “spillover effects” on lay citizens—that is, long-term effects on participating citizens and effects on non-participating citizens. We answer this question by means of a systematic review of the empirical research on minipublics’ spillover effects published before 2019. We identify 60 eligible studies published between 1999 and 2018 and provide a synthesis of the empirical results. We show that the evidence for most spillover effects remains tentative because the relevant body of empirical evidence is still small. Based on the review, we discuss the implications for democratic theory and outline several trajectories for future research.

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