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排序方式: 共有53条查询结果,搜索用时 31 毫秒
1.
Fortes Maira Salomão Lopes-Mori Fabiana Maria Ruiz Caldart Eloiza Teles Constantino Caroline Evers Fernanda Pagliari Sthefany de Almeida Jonatas Campos Barros Luiz Daniel Freire Roberta Lemos Garcia João Luis Headley Selwyn Arlington Navarro Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419
Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and... 相似文献
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Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
4.
F. H. Evers 《European Journal of Forest Research》1971,90(1):363-369
Zusammenfassung Im Frühjahr 1971 wurden in 50–70j?hrigen Fichtenbest?nden entlang der Bundesautobahn Stuttgart-Karlsruhe im Streckenabschnitt
Heimsheim umfangreichere Sch?den durch Auftausalze festgestellt. Nadelverf?rbungen und Ausf?lle ergaben sich nicht nur im
Spritzwasserbereich entlang der Bestandesr?nder, sondern auch bis zu 100 m ins Bestandesinnere, wenn salz-(NaCl-) haltige
Schmelzw?sser über natürliche oder künstlich angelegte Abflu\systeme in die Best?nde gelangten. Die gesch?digten Fichten wiesen
über 3‰ bis rund 7‰ Chlorid in den Nadeln auf. Bei den 70–100 m im Bestandesinnern stehenden B?umen konnten ebenfalls hohe
Cl-Konzentrationen in den Nadeln festgestellt werden, was darauf hinweist, da? die Sch?digung über den Wurzelbereich erfolgt
sein mu?te. Auch im Boden waren stark erh?hte NaCl-Konzentrationen festzustellen.
Gef?hrdet durch abflie?endes, salzhaltiges Schmelzwasser sind besonders Fichtenbest?nde auf feinlehmreichen und tonigen B?den
in Mulden-und leichten Hanglagen, auch an Hangfü?en steilerer Lagen. Die Bedrohung w?chst in submontanen und montanen Gebieten.
Aus der Baden-Württembergischen Forstlichen Versuchs- und Forschungsanstalt, Sektion Pflanzenern?hrung und Düngung 相似文献
Summary In spring of 1971, rather extensive injuries were noted in 50–70 year old Norway spruce stands along the Stuttgart-Karlsruhe-Autobahn near Heimsheim. These damages are attributed to the infiltration of rock salt. Discolouring of needles and destruction of the trees not only occured along the border of the stands within spraying range, but was also observed up to 100 meters inside the stands where melted snow and ice containing salt had reached the stands through natural or artifical drainage systems. Needles of the damaged spruces contained from over 3‰ to approximately 7‰ of chlorine. Since needles of trees at 70 to 100 meters inside the stands also contained high concentrations of chlorine it must be concluded that the damage has been inflicted through the root system. High concentrations of NaCl were also found in the soil. Melted snow and ice containing salt is particularly dangerous when draining into spruce stands on loamy or clayey soil in hollows or on slight slopes, as well as at the bottom of steeper slopes. Danger increases in mountains and submountains areas.
Aus der Baden-Württembergischen Forstlichen Versuchs- und Forschungsanstalt, Sektion Pflanzenern?hrung und Düngung 相似文献
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U. Ammer G. Einsele W. Arnold O. Klee R. Agerer G. Agster U. Babel J. Behringer W. Böcking F. -H. Evers W. Fleck H. Günzl K. -F. Hofmann H. Janz J. Körner I. Kottke V. Kracht A. Krebs K. Kunzweiler W. -D. Langbein H. -U. Moosmauer S. Müller E. Nickel S. Pfeiffer R. Rausch H. Schmidt-Witte O. Schwarz R. Stegmayer 《European Journal of Forest Research》1983,102(1):282-324
Ohne Zusammenfassung
(Prof. Agerer seit 1982 am Institut für Systematische Botanik, München).
(Weilimdorf)
(zuvor t?tig bei der FVA Stuttgart, siehe oben)
(Hohenheim) 相似文献
7.
8.
The expansion of oil palm monocultures into globally important Southeast Asian tropical peatlands has caused severe environmental damage. Despite much of the current focus of environmental impacts being directed at industrial scale plantations, over half of oil palm land-use cover in Southeast Asia is from smallholder plantations. We differentiated a first generation smallholder oil palm monoculture into 8 different sampling zones, and further divided the 8 sampling zones into oil palm root influenced (Proximal) and reduced root influence (Distal) areas, to assess how peat properties regulate in situ carbon dioxide (CO2) and methane (CH4) fluxes. We found that all the physico-chemical properties and nutrient concentrations except sulphur varied significantly among sampling zones. All physico-chemical properties except electrical conductivity, and all nutrient content except nitrogen and potassium varied significantly between Proximal and Distal areas. Mean CO2 fluxes (ranged between 382 and 1191 mg m−2 h−1) varied significantly among sampling zones, and between Proximal and Distal areas, with notably high emissions in Dead Wood and Path zones, and consistently higher emissions in Proximal areas compared to Distal areas within almost all the zones. CH4 fluxes (ranged between −32 and 243 µg m−2 h−1) did not significantly vary between Proximal and Distal areas, however significantly varied amongst sampling zones. CH4 flux was notably high in Canal Edge and Understorey Ferns zones, and negative in Dead Wood zone. The results demonstrate the high heterogeneity of peat properties within oil palm monoculture, strengthening the need for intensive sampling to characterize a land use in the tropical peatlands. 相似文献
9.
In central Europe and to some degree in North America, the so called “new type” forest damages occur over large areas. Various
studies indicate the declines are more or less frequently associated with nutritional disturbances that have developed within
rather short time periods. The most common disorder is a Mg deficiency that produces specific discoloration symptoms such
as tip-yellowing in Norway spruce. But also K deficiencies and other disturbances exist in coniferous as well as in deciduous
forests. Good correlations between the site specific substrate chemistry and the actual nutritional status of the trees and
stands were found. To explain the sudden and widespread development of the forest declines adverse anthropogenic influences
such as increased N and H+ deposition, land use and forestry mismanagement as well as natural stresses are discussed. The hypothesized causal mechanisms
are multiple, but include generally soil degradation processes associated with losses of alkaline nutrient ions from the rooted
solum. Recent and previous fertilization (and liming) experiments have shown that a fast and sustained revitalization and
restabilization of declining forest ecosystems marked by nutrient deficiencies can be achieved. This was demonstrated by chemical
and histological foliar analyses and the visible improvement of the trees. Soil analyses also revealed a positive change of
the chemical soil status when site and stand specific fertilizer applications were utilized in the appropriate amounts. However,
under certain site and stand conditions risks and limitations exist that have to be evaluated when fertilization practices
are discussed. To overcome or minimize these influences the treatments must be adapted to the site, and stand specific fertilization
needs as indicated by soil and foliar analysis, humus form, hydrologic parameter and atmospheric deposition rates. 相似文献
10.
Louisa B. Evers Richard F. Miller Paul S. Doescher Miles Hemstrom Ronald P. Neilson 《Strength and Conditioning Journal》2013,66(3):313-329
Disturbances and their interactions play major roles in sagebrush (Artemisia spp. L.) community dynamics. Although impacts of some disturbances, most notably fire, have been quantified at the landscape level, some have been ignored and rarely are interactions between disturbances evaluated. We developed conceptual state-and-transition models for each of two broad sagebrush groups—a warm-dry group characterized by Wyoming big sagebrush (Artemisia tridentata Nutt. subsp. wyomingensis Beetle & Young) communities and a cool-moist group characterized by mountain big sagebrush (Artemisia tridentata Nutt. subsp. vaseyana [Rydb.] Beetle) communities. We used the Vegetation Dynamics Development Tool to explore how the abundance of community phases and states in each conceptual model might be affected by fire, insect outbreak, drought, snow mold, voles, sudden drops in winter temperatures (freeze-kill), livestock grazing, juniper (Juniperus occidentalis var. occidentalis Hook.) expansion, nonnative annual grasses such as cheatgrass (Bromus tectorum L.), and vegetation treatments. Changes in fuel continuity and loading resulted in average fire rotations of 12 yr in the warm-dry sagebrush group and 81 yr in the cool-moist sagebrush group. Model results in the warm-dry sagebrush group indicated postfire seeding success alone was not sufficient to limit the area of cheatgrass domination. The frequency of episodes of very high utilization by domestic livestock during severe drought was a key influence on community phase abundance in our models. In the cool-moist sagebrush group, model results indicated at least 10% of the juniper expansion area should be treated annually to keep juniper in check. Regardless, juniper seedlings and saplings would remain abundant. 相似文献