998 resultados para BIALOWIEZA PRIMEVAL FOREST


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We have determined the mitochondrial genotype of liver fluke present in Bison (Bison bonasus) from the herd maintained in the Bialowieza National Park in order to determine the origin of the infection. Our results demonstrated that the infrapopulations present in the bison were genetically diverse and were likely to have been derived from the population present in local cattle. From a consideration of the genetic structure of the liver fluke infrapopulations we conclude that the provision of hay at feeding stations may be implicated in the transmission of this parasite to the bison. This information may be of relevance to the successful management of the herd. © 2012 Elsevier B.V.

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Apex predators perform important functions that regulate ecosystems worldwide. However, little is known about how ecosystem regulation by predators is influenced by human activities. In particular, how important are top-down effects of predators relative to direct and indirect human-mediated bottom-up and top-down processes? Combining data on species' occurrence from camera traps and hunting records, we aimed to quantify the relative effects of top-down and bottom-up processes in shaping predator and prey distributions in a human-dominated landscape in Transylvania, Romania. By global standards this system is diverse, including apex predators (brown bear and wolf), mesopredators (red fox) and large herbivores (roe and red deer). Humans and free-ranging dogs represent additional predators in the system. Using structural equation modelling, we found that apex predators suppress lower trophic levels, especially herbivores. However, direct and indirect top-down effects of humans affected the ecosystem more strongly, influencing species at all trophic levels. Our study highlights the need to explicitly embed humans and their influences within trophic cascade theory. This will greatly expand our understanding of species interactions in human-modified landscapes, which compose the majority of the Earth's terrestrial surface.

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揭示苔藓植株元素含量及其时空差异性是深入开展利用苔藓植物指示环境和筛选理想监测藓种的科学基础。采用微波消解(ICP-AES)方法对九寨沟自然遗产地原始林景点停车场周围三个采样带:I为停车场植被小岛(PS),向外约120 m半径为II带(D120),再向外距离约1,000 m为III带(D1000)和3个方向上的大羽藓和毛尖青藓2种苔藓中13种元素(A1, S, Ca, P, Cu, Fe, K, Mg, Mn, Pb, Ni,Zn和Cd)含量进行了测定和比较,并对采自边坡方向(PS-3)上2005和2007年的4种苔藓植物(南木藓、大羽藓、平藓和厚角絹藓)也进行了13种元素含量的测定和比较。同时对九寨沟自然遗产地、黄龙自然遗产地、夹金山和梦笔山的冷杉原始林4个地区的3种苔藓中(大羽藓、锦丝藓和塔藓)的A1、Ca、Cu、Fe、K、Mg、P、Zn、C和N 10种元素含量进行测定和比较。 对大羽藓和毛尖青藓2种苔藓植物内13种元素的测定发现:1)同种苔藓对不同元素的富集能力不同。A1、Ca、K、Mg和P的元素含量在苔藓中的富集较其他元素的要高。2)不同种苔藓植物对同种元素的富集能力不同,毛尖青藓较大羽藓能够监测出更多的元素;对于被检测出的元素,毛尖青藓监测出的累积量大于大羽藓,其中累积量最大的元素是Ca为10 874.286 μg.g-1.year-1,最小的是Cu元素为5.438 μg.g-1.year-1。对05年和07年的平藓、大羽藓、南木藓和厚角絹藓元素含量的测定表明:元素在两年中的积累量是不同的。综合分析表明,苔藓生物监测方法可有效监测景点停车场机动车尾气中排放出的典型元素(如Cu、Pb、Ni、Zn、Cd等)含量,而毛尖青藓较大羽藓能更可靠的监测九寨沟自然遗产地单景点汽车尾气金属元素种类及其排放量。 对4个地区3种苔藓10种元素监测发现:1)Ca、Mg、Zn、K和Cu元素在黄龙地区的含量高于在其它地区的含量;P元素在梦笔山地区的含量为最高;Fe和Al元素在夹金山地区的含量高于在其它地区的含量。2)C元素在其它因素一致的情况下,进行不同年龄间的元素含量比较,结果显示元素含量在各年龄间并不存在明显的差异性;N元素含量与年龄的差异出现在黄龙林下及林窗的塔藓、九寨沟林下的锦丝藓及塔藓和梦笔山的塔藓中,而在锦丝藓中未出现元素含量与年龄的差异性;塔藓能检测出更多的元素种类其含量与年龄间存在显著差异,锦丝藓检测到的元素种类次之;除锦丝藓(锦丝藓在林窗中几乎检测不到元素含量与年龄间的差异性)外,其他两种藓在林窗中能检测出的元素种类大于在林下的检测种类。3)元素含量与生境间存在差异性的元素分别有:黄龙大羽藓中的Ca、P和Mg元素;九寨锦丝藓中的Zn元素;夹金山塔藓中的Al、Fe和Zn元素;梦笔山大羽藓中的Al、Fe和Mg元素及锦丝藓中的Ca元素。4)区域、年龄和生境因素对苔藓植株元素含量均达到了显著水平,但两两之间及三者之间的交互作用由于元素种类的不同存在差异。综合分析表明,苔藓植物中的元素含量受年龄、区域的影响较生境的更大。 The revelation of mosses elements content and its spatiotemporal differences is the scientific foundation of moss monitoring. To determine the feasibility of moss monitoring metal depositions derived from travel bus emiss ions in scenic spot, we collected one year-growth samples of two mosses Brachythecim piligerum and Thuidium cymbifolium with different distance (island center, 120m,1000m ) and different direction (north, south and east) far from parking site island from Yuanshilin Spot at Jiuzhaigou World Nature Heritage in the Western Sichuan of China and determined thirteen element (A1, S, Ca, P, Cu, Fe, K, Mg, Mn, Pb, Ni, Zn, Cd)contents by ICP-AES analysis method. And picked 4 kinds of mosses (Macrothamnium macrocarpu m(Reinw. etHornsch.)Fleisch.,Thuidium cymbifolium,Entodon concinnus (De Not.) Par., Neckera pennata) from the direction PS-3 in 2005 and 2007, determined 13 element contents. Collected 3 kinds of moss (Thuidium cymbifo lium, Actinothuidium Hookeri (Mitt.) and Hyolcomium splendens (Hedw.) from Jiuzhaigou natural heritage, Huanglong natural heritage, Mt. Jiajin and Mt. Mengbi in primeval forest with two habitat (undergrowth and forest gap), determined element contents of A1, Ca, Cu, Fe, K, Mg, P, Zn, C and N. We found that, 1) The elements content are difference in same type of moss. Content of A1, Ca, K, Mg and P are higher than others. 2) While the contents of A1, S, Ca, P, Cu, Fe, K and Zn had significant correlation with the different distances from parking site, the nearer the distance was, the more accumulation was; 2) Comparing to Thuidium cymbifolium, Brachythecium piligerum can test more elements which contents show the significant correlation with distances. And Brachythecium piligerum can have greater element accumulation than Thuidium cymbifolium. The element contents in two years (2005 and 2007) are different. The present study found that moss can reliably bio-indicate metal deposition from traffic emissions in one scenic spot and Brachythecium piligerum is a good moss for bio-indicating element content from traffic emissions at Jiuzhaigou World natural Heritage. Determined the 10 element contents in 4 areas through 3 kinds of moss we found that, 1) Ca, Mg, Zn, K and Cu element content is higher in the Huanglong area than in other areas, The P element content in Mt. Jiajin is higher than other areas, Fe and Al element content is higher in the Mt. Jiajin than in other areas. 2) The content of C had no significant correlation with age. As for N, this significant correlation found in Hyolcomium splendens (Hedw.) with 2 habitat in Huanglong, Actinothuidium Hookeri (Mitt.) and Hyolcomium splendens (Hedw.) with undergrowth in Jiuzhai, Hyolcomium splendens (Hedw.) in Mt. Mengbi. The types of elements which content showt he significant correlation are most in Hyolcomium splendens (Hedw.) and least in Thuidium cymbifolium. Except Actinothuidium Hookeri (Mitt.), the types of elements that content had significant correlation with age in forest gap are more than in undergrowth. 3) The elements which content had significant correlation with habitat are P, Ca and Mg in Thuidium cymbifolium in Huanglong, Zn in Actinothuidium Hookeri (Mitt.) in Jiuzhai, Al, Fe and Zn in Hyolcomium splendens (Hedw.) in Mt. Jiajin, in Mt. Mengbi Al, Fe and Mg in Thuidium cymbifolium and Ca in Actinothuidium Hookeri (Mitt.). 4)The region, the age and the habitat factor has coeffect element content. The correlationship between element contents and the age, the region is closer than habitat.

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A palynological study of a 15 m sediment core from the centre of Lake Wollingst (water depth 14,5 m) is presented. The pollen record shows 3 lateglacial thermomers, called Meiendorf, Bölling, Alleröd and the early holocene Friesland-Thermomer. The succession of forest vegetation taking place on the lake surroundings during the Holocene was typical for older moraine soils which are poor in nutrients: forest vegetation started with birch and pine, followed by hazel, oak and elm in the Boreal and by alder, lime and ash-tree in the Atlantic. Beech and hornbeam reached the area during Subboreal. However, due to the poor soils they spread out only after the Iron Age. With the deforestation during the medieval time the lake lost its character of a primeval forest lake. Lake Wollingst was oligotrophic since its origin at the end of the Pleniglacial. After medieval forest-clearing the lake has changed its quality of water particularly in connection with hemp- and flax-rotting. The modem sediments in this profile are completely disturbed. They contain reworked material, a lot of blue-green algae and remains of Bosmina longirostris indicating eutrophic conditions.

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Sacred groves are patches of forests of special spiritual significance to humans, offering also a diverse range of ecological and environmental services. We have attempted here to understand the local hydrological dynamics of a sacred forest, in terms of the benefits the village community derive, in central Western Ghats region of India. A comparative assessment has been made between two small watersheds in terms of their landscape structure (woody species composition) with soil water properties and availability of water in the respective downstream villages. The result shows that, sacred site with more primeval vegetation has close association with soil moisture in comparison to non-sacred site during dry spell of the year. The higher soil moisture ensures year long availability of water in the downstream village of the sacred site which facilitates farming of commercial crops with higher economic returns to the farmers, unlike the farmers in the other village where they face water crisis during the lean season. The study emphasizes the need for conservation endeavour on sacred groves highlighting its potential for water conservation at local and regional levels.

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Human activity has undoubtedly had a major impact on Holocene forested ecosystems, with the concurrent expansion of plants and animals associated with cleared landscapes and pasture, also known as 'culture-steppe'. However, this anthropogenic perspective may have underestimated the contribution of autogenic disturbance (e.g. wind-throw, fire), or a mixture of autogenic and anthropogenic processes, within early Holocene forests. Entomologists have long argued that the north European primary forest was probably similar in structure to pasture woodland. This idea has received support from the conservation biologist Frans Vera, who has recently strongly argued that the role of large herbivores in maintaining open forests in the primeval landscapes of Europe has been seriously underestimated. This paper reviews this debate from a fossil invertebrate perspective and looks at several early Holocene insect assemblages. Although wood taxa are indeed important during this period, species typical of open areas and grassland and dung beetles, usually associated with the dung of grazing animals, are persistent presences in many early woodland faunas. We also suggest that fire and other natural disturbance agents appear to have played an important ecological role in some of these forests, maintaining open areas and creating open vegetation islands within these systems. More work, however, is required to ascertain the role of grazing animals, but we conclude that fossil insects have a significant contribution to make to this debate. This evidence has fundamental implications in terms of how the palaeoecological record is interpreted, particularly by environmental archaeologists and palaeoecologists who may be more interested in identifying human-environment interactions rather than the ecological processes which may be preserved within palaeoecological records.

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Die vorliegende Untersuchung analysiert die Eignung der "Spechtgemeinschaft" als ökologische Indikatorengruppe und formuliert vor dem Hintergrund der Ergebnisse Forderungen und Empfehlungen für einen "spechtgerechten" Umgang mit Wäldern. Die Habitatnutzung von sieben Spechtarten beim Nahrungserwerb wurde über einen Zeitraum von zwei Jahren in urwaldartigen und forstlich genutzten Beständen verschiedener Waldgesellschaften systematisch beobachtet. Das Untersuchungsgebiet ist der Bialowieza-Wald im äußersten Osten Polens, wo in enger räumlicher Nachbarschaft Natur- und Wirtschaftswaldflächen bearbeitet werden konnten. Die Beobachtungen erfolgten zwischen Anfang März 1999 und Ende Februar 2001 und wurden zu allen Jahreszeiten durchgeführt. Vier der insgesamt sechs Probeflächen repräsentieren die wichtigste Laubwaldgesellschaft des Gebietes, das Tilio-Carpinetum, die übrigen zwei die wichtigste Nadelwaldgesellschaft, das Peucedano-Pinetum. Die Hälfte der zwischen 42 und 54 ha großen Probeflächen lag im streng geschützten Urwaldreservat des Bialowieza-Nationalparkes, die übrigen in forstlich genutzten Waldbeständen. Zusätzlich wurde ein 2,5 km langes Transekt durch bewirtschafteten Erlen-Eschen-Auenwald und sehr naturnahen Erlenbruch bearbeitet. Die Probeflächen wurden in ein Raster aus 50x50m großen Quadranten unterteilt. Zur Beobachtung der Spechte beim Nahrungserwerb erfolgten 21 Begehungen je Probefläche bzw. Transekt. Die Probeflächen wurden dazu auf parallelen Linien mit Abständen von je 100m begangen, Startpunkt und Startrichtung wurden variiert. Zur Charakterisierung der Vegetation und Bestandesstruktur erfolgten Erhebungen zur Baumartenzusammensetzung, Größenklassenverteilung der Bäume, Totholzanteil und Krautvegetation. 1332 Beobachtungen von Spechten beim Nahrungserwerb konnten ausgewertet werden. Der Buntspecht wurde in allen Flächen am häufigsten gesehen. Mittel-, Weißrücken- und Kleinspecht wurden überwiegend in den Tilio-Carpineten beobachtet, in den Naturwäldern häufiger als in den bewirtschafteten Beständen. Der Dreizehenspecht wurde im Nadelwald und stärker mit Fichten durchmischtem Laubwald angetroffen. Bei Schwarz- und Grauspecht konnte keine klare Vorliebe für bestimmte Waldgesellschaften ermittelt werden. Der Buntspecht ernährte sich vor allem im Herbst und Winter überwiegend von fetthaltigen Samen und wurde dann meist beim Bearbeiten von Fichten- oder Kiefernzapfen in Schmieden beobachtet. Der Mittelspecht suchte als "Sammelspecht" seine Nahrung vor allem an den Oberflächen der Stämme und Äste. Klein-, Weißrücken-, Dreizehen- und Schwarzspecht traten als Hackspechte in Erscheinung. Die wenigen Daten zum Grauspecht reichen nicht zur Ermittlung der bevorzugten Nahrungserwerbstechnik aus. Bei Bunt-, Mittel- und Weißrückenspecht konnte eine deutliche Vorliebe für die Stieleiche als Nahrungsbaum nachgewiesen werden. Der Dreizehenspecht ist jedoch die einzige der beobachteten Arten mit einer weitgehenden Spezialisierung auf eine bestimmte Baumart, er nutzte in allen Waldgesellschaften meist die Fichte. Insgesamt bevorzugten die Spechte Bäume mit großen Stammdurchmessern, beim Kleinspecht ist diese Vorliebe allerdings nur schwach ausgeprägt. Totholz wurde von Weißrücken-, Dreizehen- und Kleinspecht bei der Nahrungssuche bevorzugt, vom Mittelspecht jedoch nur gelegentlich genutzt. Beim Buntspecht zeigte der Totholz-Nutzungsanteil erhebliche Unterschiede zwischen verschiedenen Baumarten. Liegendes Totholz spielte in den Tilio-Carpineten im Vergleich zu stehendem Totholz und toten Teilen lebender Bäume nur eine geringe Rolle für Nahrung suchende Spechte.

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Patterns of nest construction and nest site selection of two murid rodents of the Brazilian Atlantic rainforest were described. The animals were captured in an area of about 1.5 ha of primary forest, marked, equipped with a spool-and-line device and released at the capture point. The next day we followed the thread to find their nests. In total 11 nests of Nectomys squamipes (Brants, 1827) and 13 of Oryzomys intermedius (Leche, 1886) were found. They were all egg-shaped, about 15 cm long and 10 cm wide, without any apparent entrance and consisted of dry leaves and grass. The two species differed in the selection of nest sites. The nests of N. squamipes were close to streams and built inside decomposed fallen logs or using natural entrances between the soil and tangled roots or rocky crevices. Nests of O. intermedius were built under or inside fallen logs and inside aerial root systems of palms. The spool-and-line technique used here is useful to provide detailed information on several aspects of the ecology and natural history of small mammals.

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In this study we examined the impact of weather variability and tides on the transmission of Barmah Forest virus (BFV) disease and developed a weather-based forecasting model for BFV disease in the Gladstone region, Australia. We used seasonal autoregressive integrated moving-average (SARIMA) models to determine the contribution of weather variables to BFV transmission after the time-series data of response and explanatory variables were made stationary through seasonal differencing. We obtained data on the monthly counts of BFV cases, weather variables (e.g., mean minimum and maximum temperature, total rainfall, and mean relative humidity), high and low tides, and the population size in the Gladstone region between January 1992 and December 2001 from the Queensland Department of Health, Australian Bureau of Meteorology, Queensland Department of Transport, and Australian Bureau of Statistics, respectively. The SARIMA model shows that the 5-month moving average of minimum temperature (β = 0.15, p-value < 0.001) was statistically significantly and positively associated with BFV disease, whereas high tide in the current month (β = −1.03, p-value = 0.04) was statistically significantly and inversely associated with it. However, no significant association was found for other variables. These results may be applied to forecast the occurrence of BFV disease and to use public health resources in BFV control and prevention.

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Knowledge of particle emission characteristics associated with forest fires and in general, biomass burning, is becoming increasingly important due to the impact of these emissions on human health. Of particular importance is developing a better understanding of the size distribution of particles generated from forest combustion under different environmental conditions, as well as provision of emission factors for different particle size ranges. This study was aimed at quantifying particle emission factors from four types of wood found in South East Queensland forests: Spotted Gum (Corymbia citriodora), Red Gum (Eucalypt tereticornis), Blood Gum (Eucalypt intermedia), and Iron bark (Eucalypt decorticans); under controlled laboratory conditions. The experimental set up included a modified commercial stove connected to a dilution system designed for the conditions of the study. Measurements of particle number size distribution and concentration resulting from the burning of woods with a relatively homogenous moisture content (in the range of 15 to 26 %) and for different rates of burning were performed using a TSI Scanning Mobility Particle Sizer (SMPS) in the size range from 10 to 600 nm and a TSI Dust Trak for PM2.5. The results of the study in terms of the relationship between particle number size distribution and different condition of burning for different species show that particle number emission factors and PM2.5 mass emission factors depend on the type of wood and the burning rate; fast burning or slow burning. The average particle number emission factors for fast burning conditions are in the range of 3.3 x 1015 to 5.7 x 1015 particles/kg, and for PM2.5 are in the range of 139 to 217 mg/kg.

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This exhibition was the outcome of a personal arts-based exploration of the meaning of interiority. Through the process it was found that existentially the architectural wall differentiating inside from outside does not exist but operates as a space of overlap, a groundless ground providing for dwelling in the real existential sense of the word.