274 resultados para halo—phreatophytic meadow


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The Otindag sandy land and the Guyuan region of Hebei Province lie in the agro-pastoral zone, where sandy desertification is serious. So they are typical for us to study on. In this paper, detail investigation were made on the Remote Sensing, Hydrochemistry, Chronology, grain size analyzing of research region to monitor sandy desertification and environmental background. The main conclusions are presented as following: 1. According to the diverse natural condition, the research area is divided into three types as sandy land desertification, cultivated land desertification and desertification reflected by lake change. The monitoring result of the first type shows that the main performance way of the sandy desertification in Otindag sandy land is that (1) the expansion of both the shifting dune and the half fixed sandy dune, (2) the reduce of the fixed sandy dune. While the result of the second type shows (1) the desertification land in the Guyuan region has first increasing then reducing change for about 30 years. (2) The sand mainly concentrates west of the research area and small part of wind-drift sand distributes northeast the research area with the spot shape. (3) The meadow area increases obviously. As far as the third type, the Dalai Nur lake area occurs first expanding then reducing change and the wind-drift sand around the lake first reduces then increases. 2. The land cover of the different types change with the same law. It is worth notice that the lake area changes oppositely with that of the wind-drift sand. 3. For about 5,000 a B.P. -2800 a B.P., the well developed palaeosols emerged. After that, three layer palaeosols were founded in the profile of Otindag sandy land. The analyses of grain size show that the sand grains of the south were coarser than that of the north. The sand in the north and middle were well sorted, while the south poor sorted. 4. Both the natural and human impact on the process of sandy desertification. On this research result, different regions have different influences. So the measures to improve sandy desertification should be choosed respectively.

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The soil respiration and net ecosystem productivity of Kobresia littledalei meadow ecosystem was investigated at Dangxiong grassland station, one grassland field station of Lhasa Plateau Ecosystem Research Station. Soil respiration and soil heterotrophic respiration were measured at the same time by using Li6400-09 chamber in growing season of year 2004. The response of soil respiration and its components, i.e. microbial heterotrophic respiration and root respiration to biotic and abiotic factors were addressed. We studied the daily and seasonal variation on Net Ecosystem carbon Exchange (NEE) measured by eddy covariance equipments and then the regression models between the NEE and the soil temperature. Based on the researches, we analyzed the seasonal variation in grass biomass and estimated NEE combined the Net Ecosystem Productivity with heterogeneous respiration and then assessed the whether the area is carbon source or carbon sink. 1.Above-ground biomass was accumulated since the grass growth started from May; On early September the biomass reached maximum and then decreased. The aboveground net primary production (ANPP) was 150.88 g m~" in 2004. The under-ground biomass reached maximum when the aboveground start to die back. Over 80% of the grass root distributed at the soil depth from 0 to 20cm. The underground NPP was 1235.04 g m"2.. Therefore annual NPP wasl.385X103kg ha"1, i.e.6236.6 kg C ha"1. 2. The daily variation of soil respiration showed single peak curve with maximum mostly at noon and minimum 4:00-6:00 am. Daily variations were greater in June, July and August than those in September and October. Soil respiration had strong correlation with soil temperature at 5cm depth while had weaker correlation with soil moisture, air temperature, surface soil temperature, and so on. But since early September the soil respiration had a obviously correlation with soil moisture at 5cm depth. Biomass had a obviously linearity correlation with soil respiration at 30th June, 20th August, and the daytime of 27th September except at 23lh October and at nighttime of 27th September. We established the soil respiration responding to the soil temperature and to estimate the respiration variation during monsoon season (from June through August) and dry season (May, September and October). The regression between soil respiration and 5cm soil temperature were: monsoon season (June through August), Y=0.592expfl()932\ By estimating , the soil daily respiration in monsoon season is 7.798gCO2m"2 and total soil respiration is 717.44 gCC^m" , and the value of Cho is 2.54; dry season (May, September and October), Y=0.34exp°'085\ the soil daily respiration is 3.355gCO2m~2 and total soil respiration is 308.61 gCC^m", and the value of Cho is 2.34. So the total soil respiration in the grown season (From May to October) is 1026.1 g CO2IT1"2. 3. Soil heterogeneous respiration had a strong correlation with soil temperature especially with soil temperature at 5cm depth. The variation range in soil heterogeneous respiration was widely. The regression between soil heterogeneous respiration and 5cm soil temperature is: monsoon season, Y=0.106exp ' 3x; dry season, Y=0.18exp°"0833x.By estimating total soil heterotrophic respiration in monsoon season is 219.6 gCC^m"2, and the value of Cho is 3.78; While total soil heterogeneous respiration in dry season is 286.2 gCCbm"2, and the value of Cho is 2.3. The total soil heterotrophic respiration of the year is 1379.4kg C ha"1. 4. We estimated the root respiration through the balance between soil respiration and the soil heterotrophic respiration. The contribution of root respiration to total respiration was different during different period: re-greening period 48%; growing period 69%; die-back period 48%. 5. The Ecosystem respiration was relatively strong from May to October, and of which the proportion in total was 97.4%.The total respiration of Ecosystem was 369.6 g CO2 m" .we got the model of grass respiration respond to the soil temperature at 5cm depth and then estimated the daytime grass respiration, plus the nighttime NEE and daytime soil respiration. But when we estimated the grass respiration, we found the result was negative, so the estimating value in this way was not close. 6. The estimating of carbon pool or carbon sink. The NPP minus the soil heterogeneous respiration was the NEE, and it was 4857.3kg C o ha"1, which indicated that the area was the carbon sink.

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Relationship between biology and environment is always the theme of ecology. Transect is becoming one of the important methods in studies on relationship between global change and terrestrial ecosystems, especially for analysis of its driving factors. Inner Mongolia Grassland is the most important in China Grassland Transect brought forward by Yu GR. In this study, changes in grassland community biomass along gradients of weather conditions in Inner Mongolia was researched by the method of transect. Methods of regression about biomass were also compared. The transect was set from Eerguna county to Alashan county (38° 07' 35" ~50° 12' 20" N, 101° 55' 25" -120° 20' 46" E) in Inner Mongolia, China. The sample sites were mainly chosen along the gradient of grassland type, meadow steppe-* typical steppe-*desert steppe-*steppification desert-^desert. The study was carried out when grassland community biomass got the peak in August or September, 2003 and 2004. And data of 49 sample sites was gotten, which included biomass, mean annual temperature, annual precipitation, accumulated temperature above zero, annual hours of sunshine and other statistical and descriptive data. The aboveground biomass was harvested, and the belowground biomass was obtained by coring (30 cm deep). Then all the biomass samples were dried within (80 + 5) °C in oven and weighted. The conclusion is as follows: 1) From the northeast to the southwest in Inner Mongolia, along the gradient of grassland type, meadow steppe-*typical steppe-*desert steppe-*steppification desert-* desert, the cover degree of vegetation community reduces. 2) By unitary regression analysis, biomass is negatively correlated with mean annual temperature, s^CTC accumulated temperature, ^10°C accumulated temperature and annual hours of sunshine, among which mean annual temperature is crucial, and positively with mean annual precipitation and mean annual relative humidity, and the correlation coefficient between biomass and mean annual relative humidity is higher. Altitude doesn't act on it evidently. Result of multiple regression analysis indicates that as the primary restrictive factor, precipitation affects biomass through complicated way on large scale, and its impaction is certainly important. Along the gradient of grassland type, total biomass reduces. The proportion of aboveground biomass to total biomass reduces and then increases after desert steppe. The trend of below ground biomass's proportion to total biomass is adverse to that of aboveground biomass. 3) Precipitation is not always the only driving factor along the transect for below-/aboveground biomass ratio of different vegetation type composed by different species, and distribution of temperature and precipitation is more important, which is much different among climatic regions, so that the trend of below-/aboveground biomass ratio along the grassland transect may change much through the circumscription of semiarid region and arid region. 4) Among reproductive allocation of aboveground biomass, only the proportion of stem in total biomass notably correlates to the given parameters. Stem/leaf biomass ratio decreases when longitude and latitude increase, caloric variables decrease, and variables about water increase from desert to meadow steppe. The change trends are good modeled by logarithm or binomial equations. 5) 0'-10 cm belowground biomass highly correlates to environmental parameters, whose proportion to total biomass changes most distinctly and increases along the gradient from the west to the east. The deeper belowground biomass responses to the environmental change on the adverse trend but not so sensitively as the surface layer. Because the change value of 0~10 cm belowground biomass is always more than that of below 10 cm along the gradient, the deference between them is balanced by aboveground biomass's change by the resource allocation equilibrium hypothesis.

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Surface pollen assemblages and their relationhips with the modern vegetation and climate provide a foundation for investigating palaeo-environment conditions by fossil pollen analysis. A promising trend of palynology is to link pollen data more closely with ecology. In this study, I summarized the characteristics of surface pollen assemblages and their quantitative relation with the vegetation and climate of the typical ecological regions in northern China, based on surface pollen analysis of 205 sites and investigating of modern vegetation and climate. The primary conclusions are as follows:The differences in surface pollen assemblages for different vegetation regions are obvious. In the forest communities, the arboreal pollen percentages are more than 30%, herbs less than 50% and shrubs less than 10%; total pollen concentrations are more than 106 grains/g. In the steppe communities, arboreal pollen percentages are generally less than 5%; herb pollen percentages are more than 90%, and Artemisia and Chenopodiaceae are dominant in the pollen assemblages; total pollen concentrations range from 103 to 106 grains/g. In the desert communities, arboreal pollen percentages are less than 5%. Although Chenopodiaceae and Artemisia still dominate the pollen assemblages, Ephedra, Tamaricaceae and Nitraria are also significant important in the pollen assemblages; total pollen concentrations are mostly less than 104grains/g. In the sub-alpine or high and cold meadow communities, arboreal pollen percentages are less than 30%. and Cyperaceae is one of the most significant-taxa in the pollen assemblages. In the shrub communities, the pollen assemblages are consistent with the zonal vegetation; shrub pollen percentages are mostly less than 20%, except for Artemisia and Hippophae rhamnoides communities.There are obvious trends for the pollen percentage ratios of Artemisia to Chenopodiaceae (A/C), Pinus to Artemisia (P/A) and arbor to non-arbor (AP/NAP) in the different ecological regions. In the temperate deciduous broad-leaved forest region, the P/A ratios are generally higher than 0.1, the A/C ratios higher than 2 and the AP/NAP ratios higher than 0.3. In the temperate steppe regions, the P/A ratios are generally less than 0.1, the A/C ratios higher than 1 and the AP/NAP ratios less than 0.1. In the temperate desert regions, the P/A ratios are generally less than 0.1, the A/C ratios less than 1, and the AP/NAP ratios less than 0.1.The study on the representation and indication of pollen to vegetation shows that Pinus, Artemisia, Betula, Chenopodiaceae, Ephedra, Selaginella sinensis etc. are over-representative in the pollen assemblages and can only indicate the regional vegetation. Some pollen types, such as Quercus, Carpinus, Picea, Abies, Elaeagus, Larix, Salix, Pterocelis, Juglans, Ulmus, Gleditsia, Cotinus, Oleaceae, Spiraea, Corylus, Ostryopsis, Vites, Tetraena, Caragana, Tamaricaceae, Zygophyllum, Nitraria, Cyperaceae, Sanguisorba etc. are under-representative in the pollen assemblages, and can indicate the plant communities well. Populus, Rosaceae, Saxifranaceae, Gramineae, Leguminosae, Compositae, Caprifoliaceae etc. can not be used as significant indicators to the plants.The study on the relation of pollen percentages with plant covers shows that Pinus pollen percentages are more than 30% where pine trees exist in the surrounding region. The Picea+Abies pollen percentages are higher than 20% where the Picea+Abies trees are dominant in the communities, but less than 5% where the parent plants are sparse or absent. Larix pollen percentages vary from 5% to 20% where the Larix trees are dominant in the communities, but less than 5% where the parent plants are sparse or absent. Betula pollen percentages are higher than 40% where the Betula trees are dominant in the communities" but less than 5% where the parent plants are sparse or absent. Quercus pollen percentages are higher than 10% where the Quercus trees are dominant in the communities, but less than 1% where the parent plants sparse or absent. Carpinus pollen percentages vary from 5% to 15% where the Carpinus trees are dominant in the communities, but less than 1% where the parent plants are sparse or absent. Populus pollen percentages are about 0-5% at pure Populus communities, but cannot be recorded easily where the Populus plants mixed with other trees in the communities. Juglans pollen accounts for 25% to 35% in the forest of Juglans mandshurica, but less than 1% where the parent plants are sparse or absent. Pterocelis pollen percentages are less than 15% where the Pterocelis trees are dominant in the communities, but cannot be recorded easily where the parent plants are sparse or absent. Ulmus pollen percentages are more than 8% at Ulmus communities, but less than 1% where the Ulmus plants mixed with other trees in the communities. Vitex pollen percentages increase along with increasing of parent plant covers, but the maximum values are less than 10 %. Caragana pollen percentages are less than 20 % where the Caragana plant are dominant in the communities, and cannot be recorded easily where the parent plants are sparse or absent. Spiraea pollen percentages are less than 16 % where the Spiraea plant are dominant in the communities, and cannot be recorded easily where the parent plants are sparse or absent.The study on the relation of surface pollen assemblages with the modern climate shows that, in the axis 1 of DCA, surface samples scores have significant correlation with the average annual precipitations, and the highest determination coefficient (R2) is 0.8 for the fitting result of the third degree polynomial functions. In the axis 2 of DCA, the samples scores have significant correlation with the average annual temperatures, average July temperatures and average January temperatures, and the determination coefficient falls in 0.13-0.29 for the fitting result of the third degree polynomial functions with the highest determination coefficient for the average July temperature.The sensitivity of the different pollen taxa to climate change shows that some pollen taxa such as Pinus, Quercus, Carpinus, Juglans, Spiraea, Oleaceae, Gramineae, Tamariaceae and Ephedra are only sensitive to the change in precipitation.

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As a prominent form of land use across much of upland Europe, extensive livestock grazing may hold the key to the sustainable management of these landscapes. Recent agricultural policy reform, however, has resulted in a decline in upland sheep numbers, prompting concern for the biodiversity value of these areas. This study quantifies the effects of varying levels of grazing management on plant, ground beetle and breeding bird diversity and assemblage in the uplands and lowlands of hill sheep farms in County Kerry, Ireland. Farms represent a continuum of light to heavy grazing, measured using a series of field indicators across several habitats, such as the internationally important blanket bog, home to the ground beetle, Carabus clatratus. Linear mixed effects modelling and non-metric multidimensional scaling are employed to disentangle the most influential management and environmental factors. Grazing state may be determined by the presence of Molinia caerulea or Nardus stricta, and variables such as % traditional ewes, % vegetation litter and % scrub prove valuable indicators of diversity. Measures of ecosystem functioning, e.g. plant biomass (nutrient cycling) and % vegetation cover (erosion rates) are influenced by plant diversity, which is influenced by grazing management. Levels of the ecosystem service, soil organic carbon, vary with ground beetle abundance and diversity, potentially influencing carbon sequestration and thereby climate change. The majority of species from all three taxa are found in the lowlands, with the exception of birds such as meadow pipit and skylark. The scale of measurement should be determined by the size and mobility of the species in question. The challenge is to manage these high nature value landscapes using agri-environment schemes which enhance biodiversity by maintaining structural heterogeneity across a range of scales, altitudes and habitats whilst integrating the decisions of people living and working in these marginal areas.

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Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, and covering up the birds' eyes strongly reduces neuronal activation. These findings suggest that Cluster N processes light-dependent magnetic compass information in night-migrating songbirds. The aim of this study was to test if Cluster N is active during daytime migration. We used behavioural molecular mapping based on ZENK activation to investigate if Cluster N is active in the meadow pipit (Anthus pratensis), a day- and night-migratory species. We found that Cluster N of meadow pipits shows high neuronal activity under dim-light at night, but not under full room-light conditions during the day. These data suggest that, in day- and night-migratory meadow pipits, the light-dependent magnetic compass, which requires an active Cluster N, may only be used during night-time, whereas another magnetosensory mechanism and/or other reference system(s), like the sun or polarized light, may be used as primary orientation cues during the day.

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1. The effect of habitat fragmentation was investigated in two adjacent, yet separate, intertidal Zostera marina beds in the Salcombe Estuary, Devon, UK. The seagrass bed on the west bank comprised a continuous meadow of ca. 2.3 ha, whilst the bed on the east bank of the estuary was fragmented into patches of 6–9 m2.2. Three 10 cm diameter core samples for infaunal macroinvertebrates were taken from three stations within each bed. No significant difference was found in univariate community parameters between beds, or in measured seagrass parameters. However, multivariate analysis revealed a significant difference in community composition, due mainly to small changes in species abundance rather than differences in the species present.3. The species contributing most to the dissimilarity between the two communities were polychaetes generally associated with unvegetated habitats (e.g. Magelona mirabilis) and found to be more common in the fragmented bed.4. A significant difference in median grain size and sorting coefficient was recorded between the two beds, and median grain size was found to be the variable best explaining multivariate community patterns.5. The results of the study provide evidence for the effects of habitat fragmentation on the communities associated with seagrass beds, habitats which are of high conservation importance. As the infaunal community is perhaps intuitively the component least likely to be affected by fragmentation at the scale observed, the significant difference in community composition recorded has consequences for more sensitive and high-profile parts of the biota (e.g. fish), and thus for the conservation of seagrass habitats and their associated communities.

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En los últimos años han aparecido nuevas formas de turismo más sostenibles, donde existen elementos relacionados con el descanso, el disfrute y la protección del medio ambiente o el conocimiento de la cultura local, a través de políticas que favorecen la sostenibilidad del destino. En este sentido, el ecoturismo se configura como una tipología turística que se desarrolla en contacto con la naturaleza. Este turismo ayuda a mejorar el desarrollo socioeconómico de las comunidades locales, a la vez, que fomenta la conservación de los recursos naturales y el respeto hacia el medio ambiente. Aunque, esta tipología de turismo también genera importantes impactos negativos. El objetivo principal de esta investigación es analizar los impactos socioeconómicos, culturales y medioambientales percibidos por el ecoturismo por parte de los residentes de comunidades rurales de República Dominicana. La técnica de recolección de datos utilizada ha consistido en un cuestionario. Entre las principales conclusiones, cabe destacar que actualmente no se perciben impactos negativos, pero si hay una serie de elementos que hay que ir considerando, con la finalidad de que no se conviertan en un impacto a corto plazo para la comunidad rural.

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We explored the relationships between perturbation-driven population decline and genetic/genotypic structure in the clonal seagrass Posidonia oceanica, subject to intensive meadow regression around four Mediterranean fish-farms, using seven specific microsatellites. Two meadows were randomly sampled (40 shoots) within 1,600 m2 at each site: the “impacted” station, 5–200 m from fish cages, and the “control” station, around 1,000 m downstream further away (considered a proxy of the pre-impact genetic structure at the site). Clonal richness (R), Simpson genotypic diversity (D*) and clonal sub-range (CR) were highly variable among sites. Nevertheless, the maximum distance at which clonal dispersal was detected, indicated by CR, was higher at impacted stations than at the respective control station (paired t-test: P < 0.05, N = 4). The mean number of alleles (Â) and the presence of rare alleles ( r) decreased at impacted stations (paired t-test: P < 0.05, and P < 0.02, respectively, N = 4). At a given perturbation level (quantified by the organic and nutrient loads), shoot mortality at the impacted stations significantly decreased with CR at control stations (R 2 = 0.86, P < 0.05). Seagrass mortality also increased with  (R 2 = 0.81, P < 0.10), R (R 2 = 0.96, P < 0.05) and D* (R 2 = 0.99, P < 0.01) at the control stations, probably because of the negative correlation between those parameters and CR. Therefore, the effects of clonal size structure on meadow resistance could play an important role on meadow survival. Large genotypes of P. oceanica meadows thus seem to resist better to fish farm-derived impacts than little ones. Clonal integration, foraging advantage or other size-related fitness traits could account for this effect.

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Goldin-Meadow (2015) presents an exceptional synthesis of work from studies of children acquiring language under variable circumstances of input or processing abilities. Deaf children who acquire homesign without any well- formed model from which to learn language represent a powerful example. Goldin-Meadow argues that the resilient properties of language that nevertheless emerge include simple syntactic structures, hierarchical organisa- tion, markers modulating the meaning of sentences, and social-communicative functions. Among the fragile or input-dependent properties are the orders that the language follows, the parts into which words are decomposed, and the features that distinguish nominals from predicates. Separation of these two types of properties poses questions concerning the innate constraints on language acquisition (perhaps these equate to the resilient properties) and con‐ cerning the specificity of processes to language (e.g., whether properties such as hierarchical organisation are specific to language or originate in the structure of thought). The study of the resilient properties of human language in the face of adversity and the relation of these properties to the information that is encoded in the human genome represent a research strategy that draws inferences about species universals (properties that all humans share) from data about individual differences (IDs; factors that make humans different from one another). In the following, we suggest three reasons to be cautious about this approach.

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A wild bee community in southern St. Catharines, Ontario, Canada, was studied from 2003 to 2012 to analyze the effects of primary succession on abundance and diversity. At a former landfill site near Brock University, which previously contained no bees, the number of bees and bee species was expected to increase rapidly following measures to restore the site to grassy meadow habitat. The Intermediate Disturbance Hypothesis (IDH) states that over time, succession occurs. Abundance and diversity increase initially and peak when pioneers coexist with specialized species, then decline because of competitive exclusion. Alternatively, abundance and diversity may continue to increase and stabilize without declining. Bees were sampled repeatedly among years from newer restoration sites (revegetated in 2003), older restoration sites on the periphery of the former landfill (revegetated in 2000), and nearby low disturbance grassy field (i.e. control) sites. In the newer sites, bee abundance and diversity increased then decreased while in older restoration and control sites mainly decreased. This pattern of succession matches the general predictions of the IDH, although declines were at least partially related to drought. By 2006, total bee abundance levels converged among all sites, indicating rapid colonization and succession, and by 2012 diversity levels were similar among sites as well, suggesting that the bee community was fully restored or nearly so within the ten-year study period.

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Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

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Present study consists the species diversity, abundance and community structure of ichthyofauna in the seagrass meadow of Minicoy Atoll, Lakshadweep Islands. Two hundred and three species of fishes were recorded during the study, from four stations in the Atoll. They belonged to 2 classes, 11orders, 43 families and 93 genera. Six species belonged to the class Chondreichthyes and 197 species to Osteichthyes. Family Pomacentridae showed maximum abundance of species (22%). Station I, having close proximity to the coral reefs, observed the maximum number of families (37) and species (129) and that with minimum number was in station II (23 families and 52 species). Bray-Curtis similarity plot showed a similarity range of 22 to 52%, seasonally. Station I showed highest Shannon-Wiener diversity index (H’log2) (4.22) during August and the lowest (2.91) during June. Stations I and III showed comparatively higher abundance and diversity of fishes. Variability in seagrass habitat structure and the interaction with coral reefs influenced the species composition and diversity of fishes in Minicoy Atoll. The findings of the present investigation can be used as baseline information for the fishery resource management of the region

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Geographically, Taiwan is an Island and situated in the northeast of Asia, on the western side of the Pacific Basin, at the southeast of main China, south of Japan, and north of the Philippines. The main topographic character is the longitudinally oriented mountainous area. More than 200 peaks rise above 3000 m. They departed Taiwan into two lowland areas, an eastern and western plain. Taiwan is departed into subtropical (north area) and tropical zone (south area), which have a warm and humid climate, due to the Tropic of Cancer passing through. The average annual temperature in the lowland amounts to 28°C (7~38°C). The temperate climate also presents in the mountainous areas. The tropical typhoons usually come in summer and bring heavy rain, while the monsoon seasons have an important effect on the regional rainfall distribution. The mean annual rainfall of Taiwan is about 2600 mm (1000~6700 mm); the mountainous areas receive more rain than the lowlands. In Taiwan, according to different temperature and vegetation, the ecological environments were given rise to vertical biotic zonations, and form five major types: highland snowfield, highland meadow, coniferous forest, deciduous forest, and tropical forest. Six National Parks in Taiwan are located in the mountainous areas, in the north, the south, and on Jinmen Island. The National Parks represent about 8.4% of the country area. In this study, the collection sites are situated in Yangmingshan, Shei-Pa, Yushan, and Kenting National Park. Due to the island isolation, the proportions of endemic species are great in Taiwan, which also presents a high biodiversity. There are 4255 species of vascular plants including 1133 endemic. 5936 species in 1276 genera of fungi are hitherto reported in Taiwan. Among them, 233 Corticiaceae species were recorded, over one third (79 species) of them are known only from Taiwan. The first fungal report in Taiwan is about Phytophthora cyperi, published by the Japanese researcher T. Kawakami in 1904. Therefore, the history of research about fungi in Taiwan is more than one hundred years old. An eminent Japanese mycologist K. Sawada made an intensive survey from 1919 to 1959, and reported 2464 fungi species in his eleven volumes of “Descriptive Catalogue of Formosan Fungi”. However, only a few species (21 species in 9 genera) of Corticiaceae were recorded. From 1973, Chen and Lin resumed the study on Corticiaceae, and also some other foreign mycologists contributed for this field after 1980. The German research group lead by Franz Oberwinkler from Tübingen University collected in Taiwan several times. They published a number of new species and new records. Since 1989, S. H. Wu, a Taiwanese mycologist, has published a great amount of reports on corticioid fungi from Taiwan. Corticioid fungi were made up by the large and heterogeneous unnatural family Corticiaceae and other resupinate fungi belonging to other natural families in the Agaricomycetes. Molecular studies have shown that corticioid genera are distributed across all major clades of Agaricomycetes indicating that the corticioid fungi represent a polyphyletic group. They have resupinate fruitbodies and similar habitats. Species are characterized by simple fruitbody, more or less effused, and present smooth, porioid, grandinioid to odontioid hymenial surface. The fruitbodies are differently colored and usually soft to tough. Most of the Corticiaceae species are wood-saprobic organisms and gain the energy from the decomposing of wood-substrate such as cellulose or lignin. Materials for this study were collected by the author and other mycologists in Taiwan during surveys in April and May 1996, and March 2007, using the spring season with its high humidity and warm climate which are optimal conditions for the development of fungi. For assembling, the convenience sampling method was used in this study. This approach was chosen because it enables to detect a high biodiversity in a short time, and also to find species with rare or patchy distribution. The collecting sites from the North to the South include four National Parks and some preserved forests. They cover many different habitats such as low lands and high mountains. Fresh specimens were dried and analysed with a light microscope. 265 specimens belonging to Corticiaceae were studied in this research. Among them, 50 species in 21 genera including 11 new records and 10 new species were described with text and drawing. Four new species are belonging to Hyphodontia (H. sp. nov. 1, H. sp. nov. 2, H. sp. nov. 3, and H. sp. nov. 4), four to Schizopora (Sch. sp. nov. 1, Sch. sp. nov. 2, Sch. sp. nov. 3, and Sch. sp. nov. 4), one in Trechispora (T. sp. nov. 1), and one in Tubulicrinis (T. sp. nov. 1). Species recorded as new are Aleurodiscus amorphus, Botryohypochnus isabellinus, Hyphodontia cineracea, Hyphodontia palmae, Hypochnicium vellereum, Merulius tremellosus, Metulodontia nivea, Paullicorticium ansatum, Phlebia radiata, Phlebiella ardosiaca, and Xylobolus frustulatus. Besides, Botryohypochnus, Merulius, Metulodontia, Paullicorticium, and Xylobolus are also newly recorded genera in Taiwan. The genus Hyphodontia presents the highest diversity with 20 out of 50 species recorded. The second important genus is Hyphoderma, however with only 5 species. This indicates that Hyphodontia and Hyphoderma have a higher ability to develop in variable environments and approximately shows the predominance of these two genera in Taiwanese Corticiaceae. There are 11 new records out of the 50 species recorded, representing 22%. Some species, e.g. Hypochnicium vellereum and Paullicorticium ansatum were in the past recorded only in Europe and North America with cold and temperate climate. The samples of them are for the first time found in the subtropical belt, and display some difference from those of temperate regions. These collections should be molecularly investigated to clarify if they represent the same species of temperate areas. Patchily distributed species, for example Phlebiella ardosiaca, previously known only in Europe, and Hyphodontia palmae collected only in Brazil, were first recorded in different continents. Two possibilities are indicated by these new records: they are worldwide species but very rare to be found, or the Taiwanese specimens are taxonomically different. More survey from other continents and molecular study for these collections should be done in the future to solve this question. The distribution of Corticiaceae in Taiwan presents the variations in the north, central, and south areas and shows the diversity in lowlands and high mountains. The results of this study provide the evidence that the temperate Corticiaceae species displays a wider distribution. Subtropical and tropical taxa probably have also high dispersal capacities, and could possibly be found in the future in neighboring areas such as China, Japan, Korea or South Asia, but this needs further researches. In the total of 50 species, 10 new taxa were described in this study, giving about 20%. Some new species (e.g. Hyphodontia sp. 1, Hyphodontia sp. 2, and Hyphodontia sp. 3) are very similar to known species (Hyphodontia sambuci and Hyphodontia formosana), and the distinctive characters of Schizopora sp. nov. 1 are intermediate between those of Schizopora paradoxa and Hyphodontia flavipora. Thus, these small differences between the new and known species, suggest that the speciation occurred when the fungi migrated into Taiwan, due to the high diversity of environment, and amounts of the endemic plants. Taiwan is an intermediate place for the south (tropical) fungal species to migrate and adapt to north (temperate) regions. The middle and high altitude environments in Taiwan offer good conditions for the fungal speciation and possibly the occurrence of physiological changes to adapt to the temperate climate. Thus Taiwan has an important position for the biogeography of Asia mycobiota. 5936 known species in Taiwan represent about only 20% of the estimated number (24000) of Taiwanese fungal taxa. In this study, the findings (22% new records and 20% new species) indicate that amounts of unknown fungi species are expected in Taiwan. The lack of knowledge indicates that many new species are awaiting description, and fungal survey in Taiwan remains in a Pioneer phase. The last three wide surveys of Corticiaceae researches took place 20 years before this study (Chen & Lin 1977, Lin & Chen 1989, Wu 1990). After previous important contributions, the present taxonomic study comprising 21 genera is the most extensive on Corticiaceae of Taiwan.

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Incrementar las habilidades de pensamiento implicadas en la solución de problemas sociales o interpersonales en los niños sordos profundos. Enseñarles a buscar soluciones adecuadas a sus problemas. Mejorar el ajuste personal-emocional y social, y el clima relacional en la clase: interacciones profesor-alumno y entre compañeros. La muestra la forman 36 niños y niñas, divididos en dos subgrupos (sordos y oyentes). El primero lo formaban 18 niños, de los cuales 8 niños y 8 niñas eran sordos profundos, bilaterales, prelocutivos y sin ningún trastorno asociado. El resto (2 niñas), tenían pérdida auditiva severa. El segundo lo formaban 18 sujetos oyentes, con los rasgos de ser compañeros de clase del niño sordo, no ser amigo próximo, no tener problemas en habilidades sociales y no haber sido rechazado en un test sociométrico por el niño sordo. Por el amplio número de variables dependientes del trabajo, para facilitar la comprensión de los resultados se dividieron en dos grupos. El primero incluye aquellas que se refieren a la estructura de la interacción (turnos no continuados inapropiados, turno con éxito simple, turnos continuados simples, turno sin éxito, turnos iniciados sin éxito por no respuesta...) y el segundo incluye a las que corresponden al contenido de tales interacciones como (sonríe, contacto físico, pide prestado algo, se enfada, verbaliza...). Cuestionario sociométrico. Inventario Meadow Kendall. Screening test.. Programa estadístico SPSS.. El programa ha sido efectivo en la consecución de algunos de los objetivos planteados, traduciéndose en la mejora de aspectos socioemocionales y reflejándose en el incremento del ajuste emocional, social, y la autoimagen observadas por las personas del entorno cercano de estos niños. Ha ayudado a los estudiantes sordos profundos a desarrollar patrones más efectivos de conducta social. Los resultados de los cuestionarios sociométricos aplicados en todas las aulas en las que estos niños estaban integrados, no arrojaron resultados significativos en ninguna de las dos variables evaluadas, integración social e inteligencia-estudio. Se observa que las relaciones entre los compañeros de diferente status auditivo, mejora tanto en díadas como en grupo. Después del programa, se produce una mejor adaptación entre ellos, aumentan sus muestras de afecto y utilizan en mayor medida un lenguaje inteligible a todos, el de los gestos. Este tipo de programas debe formar parte del currículum escolar de todos, y en especial de estos niños, comenzando en los primeros años de escolaridad y manteniéndose, de forma que en la adolescencia tengan un mayor grado de autonomía y pensamiento reflexivo, además de interacciones sociales más maduras. Entre los beneficios que se observan en estudios como éste que combina el empleo de habilidades de pensamiento y sociales se encuentran: el que los niños, en primer lugar, se conciencian de la necesidad de pararse a pensar una decisión, para evitar la conducta impulsiva. En segundo lugar, al saber que sus acciones tienen consecuencias, puede evitar las elecciones precipitadas. En tercer lugar, vinculan la toma de decisiones a su propia reflexión personal, más que a la presión del grupo. En cuarto lugar, no se desmoronan cuando no consiguen sus propósitos sino que se plantean una solución alternativa para la próxima ocasión. Es importante hacer un seguimiento para ver si los incrementos observados se mantienen a largo plazo. Otro aspecto que requeriría una especial atención es el relacionado con la intervención en los niños sin discapacidades para aceptar e interactuar adecuadamente con los niños sordos profundos integrados, es decir, sería necesario realizar algún tipo de intervención para facilitar la interacción social positiva y la aceptación por los compañeros, de los niños con algún tipo de discapacidad.