scholarly journals Impact of soil scarification on reindeer pastures

Rangifer ◽  
1990 ◽  
Vol 10 (3) ◽  
pp. 99 ◽  
Author(s):  
Olof Eriksson ◽  
Tuomo Raunistola
Keyword(s):  
Standard Procedure ◽  
Plant Cover ◽  
Point Of View ◽  
Ground Vegetation ◽  
Long Term Effects ◽  
Surface Moisture ◽  
Positive Effects ◽  
Soil Scarification ◽  
Soil Temperatures

During recent years, soil scarification has become a standard procedure for improving seed beds after logging. Around 57 000 ha were treated, primarily through harrowing and ploughing, in the counties of Vâsterbotten and Norbotten during 1985. The positive effects of scarification, from a forestry point of view, are improved access to plant nutrients, raised soil temperatures and reduces surface moisture. The aim of the present study was to describe long-term changes in the ground vegetation following scarification. Harrowing affects 45-55% of the plant cover while ploughing affects 65-90%. 10 years after ploughing and harrowing about 20% of the surface is still without vegetation. Real long-term effects remain in dispute. It has been claimed that ploughing, at least, may lead to irreversible changes.

scholarly journals Linking floral biodiversity with nitrogen and carbon translocations in semi-natural grasslands in Lithuani

2015 ◽  
Vol 34 (2) ◽  
pp. 137-146
Author(s):  
Saulius Marcinkonis ◽  
Birutė Karpavičienė ◽  
Michael A. Fullen
Keyword(s):  
Plant Cover ◽  
Chemical Properties ◽  
Above Ground Biomass ◽  
Long Term Effects ◽  
Specific System ◽  
Ground Biomass ◽  
Natural Grasslands ◽  
Below Ground ◽  
Grassland Communities

AbstractThe aim of the present study is to evaluate the long-term effects of long-term piggery effluent application on semi-natural grassland ecotop-phytotop changes (above- and below-ground phytomass production, and carbon and nitrogen allocation in grassland communities) in relation to changes (or variability) in topsoil properties. Analysis of phytomass distribution in piggery effluent irrigated grassland communities showed that dry biomass yield varied from 1.7−5.3 t ha-1. Variability in soil and plant cover created a unique and highly unpredictable site specific system, where long-term anthropogenic influences established successor communities with specific characteristics of above- and below-ground biomass distribution. These characteristics depend more on grassland communities than on soil chemical properties. Families of grasses (Poaceae) dominated the surveyed communities and accumulated most carbon and least nitrogen, while legumes accumulated most nitrogen and lignin and least carbon. Carbon concentrations in above-ground biomass had minor variations, while accumulation of nitrogen was strongly influenced by species diversity (r = 0.94, n = 10, p <0.001) and production of above-ground biomass

IMMEDIATE AND LONG-TERM EFFECTS OF INSECTICIDE APPLICATION ON PARASITOIDS IN JACK PINE STANDS IN QUEBEC

1972 ◽  
Vol 104 (2) ◽  
pp. 263-270 ◽  
Author(s):  
Peter W. Price
Keyword(s):  
Relative Abundance ◽  
Jack Pine ◽  
Ground Vegetation ◽  
Long Term Effects ◽  
Aerial Application ◽  
Insecticide Application ◽  
Number Of Species ◽  
Adult Parasitoid ◽  
Pine Stands

AbstractParasitoid populations were sampled before, and for 4 years following, an aerial application of the insecticide phosphamidon to control a sawfly outbreak. Adult parasitoid mortality was high because of spraying, but a reservoir of parasitoids in host cocoons remained to repopulate the treated areas. In moister sites the number of species decreased and their relative abundance changed, but moderate numbers of parasitoids remained 4 years after spraying. In a dry site with little ground vegetation, none of the species present before spraying remained by the fourth year.

scholarly journals Duration of untreated psychosis as predictor of long-term outcome in schizophrenia: systematic review and meta-analysis

2014 ◽  
Vol 205 (2) ◽  
pp. 88-94 ◽  
Author(s):  
Matti Penttilä ◽  
Erika Jääskeläinen ◽  
Noora Hirvonen ◽  
Matti Isohanni ◽  
Jouko Miettunen
Keyword(s):  
Negative Symptoms ◽  
Meta Analysis ◽  
Hospital Treatment ◽  
Duration Of Untreated Psychosis ◽  
Long Term Effects ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Positive Effects ◽  
Early Intervention In Psychosis

BackgroundDuration of untreated psychosis (DUP) is one of the few potentially modifiable predictors of outcomes of schizophrenia. Long DUP as a predictor of poor short-term outcome has been addressed in previous meta-analyses, but the long-term effects of DUP remain unclear.AimsTo analyse the associations between DUP and long-term outcomes of schizophrenia.MethodA systematic literature search was performed using seven electronic databases and manual searches. Random effects weighted meta-analysis with correlation coefficients was used to pool the results.ResultsWe identified 3493 unique publications, from which 33 samples met our predefined selection criteria. Long DUP correlated statistically significantly with poor general symptomatic outcome, more severe positive and negative symptoms, lesser likelihood of remission and poor social functioning and global outcome (correlations 0.13–0.18). Long DUP was not associated with employment, quality of life or hospital treatment.ConclusionsThe small but mostly consistent correlation between long DUP and poor outcome indicates that early intervention in psychosis may have at least subtle positive effects on the long-term course of illness.

SHORT- AND LONG-TERM EFFECTS OF THE 9/11 EVENT: THE INTERNATIONAL EVIDENCE

2005 ◽  
Vol 08 (07) ◽  
pp. 947-958 ◽  
Author(s):  
VINCENT RICHMAN ◽  
MICHAEL R. SANTOS ◽  
JOHN T. BARKOULAS
Keyword(s):  
Stock Market ◽  
Capital Markets ◽  
Systematic Risk ◽  
Point Of View ◽  
Long Term Effects ◽  
Market Reactions ◽  
Theoretic Point ◽  
Short And Long Term ◽  
Stock Market Reactions

This paper analyzes the short- and long-term effects of the September 11, 2001 terrorist attacks on a comprehensive sample of stock market indices from 33 industrial and emerging economies. From a finance-theoretic point of view, we employ the international capital asset pricing model (ICAPM) to analyze the incidence of the 9/11 event. Consistent with expectations, we document statistically negative short-term stock market reactions to the 9/11 event for 28 countries. More importantly, we find increases in the level of systematic risk for 10 stock markets which attest to the presence of negative permanent effects emanating for the 9/11 event. However, a great many capital markets (including the US, Canada, Japan, China, Russia, and the largest European economies) did not experience statistically significant increases in systematic risk in the post-9/11 period. The decisiveness of the evidence clearly points in the direction of resilience and flexibility of the world capital markets.

Long-Term Effects of Diet on the Biology of the Lake Trout and the Fishery in Lake Opeongo, Ontario

1970 ◽  
Vol 27 (1) ◽  
pp. 125-146 ◽  
Author(s):  
N. V. Martin
Keyword(s):  
Lake Trout ◽  
Feeding Activity ◽  
Salvelinus Namaycush ◽  
Point Of View ◽  
Average Weight ◽  
Coregonus Clupeaformis ◽  
Long Term Effects ◽  
Food Content ◽  
Coregonus Artedii

From 1936 to 1965 food content was examined in 17,171 Lake Opeongo lake trout (Salvelinus namaycush). The diet is analysed from the point of view of frequency of occurrence of foods, their weight, feeding activity of trout, size of trout and size of food, and seasonal and annual changes in food habits.In the late 1940's and early 1950's perch, Perca flavescens, largely disappeared from the diet. The lake trout initially turned to lake whitefish, Coregonus clupeaformis, and then to the cisco, Coregonus artedii, introduced into Lake Opeongo in 1948.As a result of these dietary changes lake trout are now heavier and rate of growth has improved. Age and size at maturity is later and there are fewer infertile fish. Egg counts, egg size, and ovary weights are now greater, particularly in the medium-sized lake trout.In the fishery the average weight of individual trout taken has almost doubled. About 25% more of the immature stock is exploited by the recent fishery. The harvest and catchability of lake trout has remained generally constant on a numerical basis but show an improvement on a poundage basis in the more recent years. The possible effects of these changes on the character of the fishery are discussed.

Verification of Ingroup Identity as a Longitudinal Mediator between Intergroup Contact and Outgroup Evaluation

2013 ◽  
Vol 16 ◽  
Author(s):  
Angel Gómez ◽  
Anja Eller ◽  
Alexandra Vázquez
Keyword(s):  
High School Students ◽  
Intergroup Contact ◽  
Long Term Effects ◽  
School Students ◽  
Cross Sectional ◽  
Positive Effects ◽  
Group Members ◽  
Ingroup Identity ◽  
Continue Work

AbstractAlmost six decades of research have consistently demonstrated that intergroup contact is one of the most powerful ways of improving intergroup attitudes. At least two important limitations, however, still compel researchers to continue work in this area: the issue of long-term effects of contact, and the processes underlying such effects. This report makes a theoretical and empirical contribution with regard to these two aspects introducing a new mediator of the effects of contact: verification of qualities of typical ingroup members that may or may not characterize individual group members (e.g. verification of ingroup identities). One hundred and forty-two high school students participated in a two-wave longitudinal study with 12 weeks’ lag in Spain. Cross-sectional and longitudinal mediational analyses using multiple imputation data showed that intergroup contact improves general outgroup evaluation through increasing verification of ingroup identities. This research demonstrates the relevance of considering verification of ingroup identity as a mediator for the positive effects of intergroup contact.

scholarly journals Ileal transposition in rats influenced glucose metabolism and HSP70 levels

2015 ◽  
Vol 10 (1) ◽  
Author(s):  
Dominika Stygar ◽  
Tomasz Sawczyn ◽  
Bronisława Skrzep-Poloczek ◽  
Iwona Karcz-Socha ◽  
Bogdan Doleżych ◽  
...  
Keyword(s):  
Glucose Metabolism ◽  
Glycogen Synthase ◽  
Glycolytic Enzyme ◽  
Diabetes Remission ◽  
Distal Ileum ◽  
Zucker Rats ◽  
Ileal Transposition ◽  
Long Term Effects ◽  
Positive Effects

AbstractObjective: Ileal transposition procedure (IT), in combination with sleeve gastrectomy, is widely used to induce diabetes remission and to control related metabolic abnormalities. A transposition of a long segment of distal ileum in obese Zucker rats improved glucose tolerance 6 months after IT. The premise of our study was to to examine the long - term effects of ileum transposition on the liver glycolytic enzymes content in a euglycemic group of operated Zucker rats. Methods: Twenty male Zucker rats underwent either the transposition of 50% distal ileum or a sham surgery. Six months after surgery, liver tissue concentrations of glycogen synthase kinase alpha (GSK-3α), glucose 6-phosphatase (G6PC), glycogen phosphorylase (PYGM) and phosphofructokinase (PFK) and HSP70 were assessed by immunoenzymatic methods. Results: HSP70 values were significantly higher in the IT group compared to SHAM. G6PC liver concentrations in the IT group were almost 1.45-fold lower than in the SHAM operated rats. Statistical analyses (F-test) showed HSP70 levels were significantly related to caveolin-1and SHAM group. Conclusions: Lowered glycolytic enzyme concentrations assessed in the liver suggest positive effects on glucose metabolism in long-term observations.

Short and long-term effects of fire and vegetation cover on four lizard species in Amazonian savannas

2020 ◽  
Author(s):  
Erika dos Santos Souza ◽  
Albertina P. Lima ◽  
William E. Magnusson ◽  
RICARDO ALEXANDRE KAWASHITA-RIBEIRO ◽  
Rodrigo Ferreira Fadini ◽  
...  
Keyword(s):  
Vegetation Cover ◽  
Long Term Effects ◽  
Short Term ◽  
Lizard Species ◽  
Random Factor ◽  
Positive Effects ◽  
Temporal Sampling ◽  
Short And Long Term ◽  
Main Effects

Ecological succession in tropical savannas is limited by seasonal fire, which affects habitat quality. Although fire may cause negligible or positive effects on animals occupying savannas, most short-term studies (months to a few years) are based on a single temporal sampling snapshot, and long-term studies (decades) are rare. We sampled four lizard species in Amazonian savannas to test the effects of fire and vegetation cover on lizard densities at two temporal scales. In the short-term, we use three sampling snapshots to test the effects of fire and vegetation cover on estimated lizard densities over the subsequent 1–5 years. In the long-term, we test the effects of fire and changes in vegetation cover over 21 years on current lizard density differences. In the short-term, species responses were usually consistent with foraging and thermoregulation modes. However, the results were not consistent among species and years, although the variances in species density explained by year as a random factor were generally low. In the long-term, the main effects of fire and vegetation cover show that lizard densities may change spatially, but not necessarily temporarily. Wildfire is a natural resource of savannas and apparently have little impact on resident lizards of that ecosystem.

Mikroökonometrische Evaluation der ökonomischen Wirkungen betrieblicher Mitbestimmung - Möglichkeiten und Grenzen des Matching-Ansatzes / Microeconometric Evaluation of Economic Effects of Workers Participation - Options und Limits of the Matching Approach

2006 ◽  
Vol 226 (5) ◽  
Author(s):  
Birgit Schultz
Keyword(s):  
Point Of View ◽  
Economic Effects ◽  
Small Samples ◽  
Long Term Effects ◽  
Works Councils ◽  
East German ◽  
Iab Establishment Panel ◽  
Microeconometric Evaluation ◽  
Short Time

SummaryThe evaluation of economic effects of workers participation is not simple from the methodical point of view because of specific characteristics of establishments with works councils. Especially recent studies show contradictory results. In this study problems are pointed out, discussed, and options for solution are presented on the example of workers participation in East German establishments of industry and construction by the IAB-Establishment Panel.An optimal matching-algorithm which supplies good matching-results for small samples to assign ‘statistical establishment-twins’ is applied. But by reason of very short primarily spells it can only calculate short time effects. Therefore, the matching method is additionally used to construct longer observation periods. By this new application establishments with recently founded works councils are matched with so called ‘proxy establishments’ with existing works councils. As a result short observation periods are prolonged and information about long-term effects can be given.The effects on productivity, profitability and qualification level of employees show neither in short-term nor in long-term a significant impact on workers’ participation.

scholarly journals Effects of Season of Burning on the Microenvironment of Fescue Prairie in Central Saskatchewan

2003 ◽  
Vol 117 (2) ◽  
pp. 257 ◽  
Author(s):  
O. W. Archibold ◽  
E. A. Ripley ◽  
L. Delanoy
Keyword(s):  
Plant Cover ◽  
Growing Season ◽  
Control Plot ◽  
Area Index ◽  
Growing Seasons ◽  
Soil Temperatures ◽  
Second Year ◽  
Long Term Impact ◽  
Season Of Burning

The microenvironmental effects of spring, summer and autumn burns were investigated for a small area of fescue prairie in Saskatchewan over two growing seasons. Maximum fire temperature in all burns exceeded 300°C at a height of 5-10 cm in the canopy. At a depth of 1 cm in the soil, temperature increased to 40°C during the summer burn, but was unaffected by burns at other seasons. Spring-burned grasses recovered to the same height as the unburned control plot by the end of the first summer. Grass height was similar in all plots by the end of the second growing season, but aboveground biomass in all burned plots was about half that of the control. Graminoid leaf area index at the end of the second growing season ranged from 0.65 in the control plot to 0.27 in the autumn burn. Surface albedos dropped to about 0.03 immediately after burning and took about 3 months to return to the pre-burn values near 0.20. By mid-June of the second year, albedos were similar in all plots. Soil temperatures at 50 cm depth in the burned plots were higher than in the control during the first summer and lower during the winter. The greatest winter snowpack (73 mm water equivalent) accumulated in the control, compared to 48, 35 and 25 mm in the spring, summer and autumn burned plots, respectively. In the first growing season the greatest demand for water occurred in the spring plot followed by the summer, control and autumn plots. In the second season water demand did not differ significantly among plots, reflecting the similarities in plant cover. The microenvironmental effects of a single burning episode in fescue prairie disappear rather quickly, so that there is little long-term impact on the vegetation.

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