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1.
The present study evaluated the usefulness of collection of location specific data for assessing patterns of species diversity
and endemism based on a dataset for the 10 temperate flowering plant families from the Indian Himalaya Region. Analysis was
based on 818 grid cells (15 × 15′) representing throughout the Indian Himalayan Region (IHR). Based on the existing information
on diverse aspects of the selected plant families four indices, i.e., species richness, weighted endemism, 1–4 cell endemism
and corrected weighted endemism were developed and mapped for selected plant families. Analysis revealed that endemism is
significantly (P < 0.001) correlated with species richness (1–4 cell endemic index: r = 0.85; weighted endemism; r = 0.58). On the basis of four different indices, potential areas have been identified for conservation. Data of each indices
have been overlaid to each other for identification and prioritization of endemic rich areas in the Indian Himalayan Region. 相似文献
2.
Habitat management within and outside protected areas is a key to effective conservation of wildlife. This is particularly vital for declining wildlife populations within the boundary of conservation areas, while sharing their potential habitat range with foraging livestock. In an effort to understand the habitat selection by Himalayan musk deer (Moschus chrysogaster) and explore any potential impacts of livestock grazing, we conducted the present study in a conservation area of central Nepal Himalaya. We recorded data on musk deer and livestock presence and absence (based on signs of fecal pellet, footprint, and resting site) along the elevational transect with associated topographic features (elevation, slope, aspect, distance to water, and vantage point distance) and vegetation features (tree spp., shrub spp., herb spp., and canopy-cover). Using logistic regression model we found that elevation, aspect, canopy-cover, and tree spp. in the area significantly affect the likelihood of habitat selection by musk deer. In particular, they selected the southern aspect of the area with elevation ≥ 3529 m, canopy-cover ≥ 42%, and with stands of Pinus spp. and Abies spp. Slope and canopy-cover significantly affected the foraging area selection by livestock. They selected the gentler slopes in the northern aspect of the area with altitude < 3529 m and canopy-cover < 42%. Also, presence of one group of herbivore (i.e. musk deer and livestock) was not found to affect the likelihood of habitat selection by the other group. These independent habitat selections are possibly the responses to morphological and behavioral adaptations than to impacts and interactions between these two groups of herbivores. We suggest to avoid any disturbances and livestock grazing on the area that disrupt the resources and conditions likely selected and occupied by musk deer population. 相似文献
3.
Atle Mysterud 《Oecologia》2000,124(1):130-137
Information on overlap in resource use is central to understanding of interspecific exploitation competition and resource
partitioning. Despite this, measures of diet overlap among northern ruminants in Fennoscandia is limited to one earlier study
(reindeer and sheep). Diet overlap between sympatric moose and roe deer calculated with Schoener’s index was 20.7% and 33.6%
during summer (data from one area) and winter (data from two areas), respectively, whereas average diet overlap between moose
and red deer was 32.0% during winter (data from four areas). Diet overlap between a coastal island population of red deer
and sheep was 59.3% during summer and 63.9% during winter. Summer diet overlap between a sheep and a goat population and a
sheep and a reindeer population calculated with data on main types of forage plants was 77.0% and 55.1%, respectively. However,
overlap calculated with main plant groups was sometimes considerably higher than when calculated for individual forage species.
Neither difference in feeding type nor body mass successfully predicted diet overlap between species pairs (n=9), although there tended to be negative correlation (r
p
=–0.586, P=0.098) between diet overlap of main plant groups (calculated across studies) and difference in feeding type.
Received: 19 October 1999 / Accepted: 31 January 2000 相似文献
4.
Abstract. Nutrient utilization and growth performance of Pinus roxburghii Sarg. and Quercus leucotrichophora A. Camus, the two major forest trees of the Central Himalaya Mountains between 1000 and 2000 m elevation, were analysed at different nutrient levels. The early successional P. roxburghii occurs naturally on nutrient-poor sites and the late successional Q. leucotrichophora on nutrient-rich sites. Seedlings of these two species were grown both in monoculture and mixed, in plastic bags containing 1 kg soil and representing five levels of nutrients (NPK) in a 12 : 32 : 16 ratio. The P. roxburghii seedlings showed significantly greater nutrient extraction efficiency (nutrient unit extracted by seedlings per nutrient unit in the soil) than the Q. leucotrichophora seedlings, and this difference was increased in interspecific competition, particularly at the higher nutrient levels. In interspecific competition the extraction efficiencies of P. roxburghii for N, P and K were distinctly higher than those of Q. leucotrichophora. This we consider to be the main reason for the replacement of Q. leucotrichophora by P. roxburghii, even on nutrient-rich soils, after disturbance and subsequent increase in light availability. In both the species, re-translocation of nutrients from senescing leaves declined with increasing soil fertility. For example, re-translocation for P. roxburghii was 49% N, 30% P and 32% K at the lowest soil fertility, and 20% N, 8% P and 13% K at the highest soil fertility. 相似文献
5.
The White-Winged Wood duck (Asarcornis scutulata) is an endangered forest wetland bird currently on the verge of extinction due to an array of anthropogenic pressures. It has been reported that global climate change could affect the distribution of many bird species globally. Therefore, an understanding the potential distribution of the White-Winged Wood duck in future climate scenarios could facilitate the creation of immediate conservation plans and the mitigation of subsequent threats. This is the first ever study on the distribution of White-Winged Wood Duck (WWWD) where Representative Concentration Pathway (RCP) 8.5 scenario was used to forecast the distribution of the WWWD in the Indian Eastern Himalayan region in the 2050s and 2070s. The study revealed that 1.87 % of the total area of IEH has the high potential distribution of WWWD. The state of Assam alone includes 1.68 % of the highly potential habitat in the region. It was predicted that 436.61 km2 of highly potential habitat would be lost by 2070. Changes in the annual temperature range, precipitation in the wettest months (June to September), and precipitation decrease in the warmest quarter (October to December) would result in the loss of highly potential habitats. Under the influence of climate change, the habitat of WWWD in the eastern part of the region is likely to shift towards the western part. It was found that there will be a decline in potential habitat in the Indian states of Arunachal Pradesh, Assam, Nagaland, and Tripura located in the IEH under future climate scenarios. The potential of areas located at the Bhutan and Assam border would increase for supporting WWWD as this species' requires the average annual precipitation about 1000–1200 mm. However, the simultaneous anthropogenic activity would further destroy potential habitats in the future. The current study has provided baseline data on the potential distribution of WWWD in the IEH region for immediate conservation management plans. 相似文献
6.
A. Peano P. Tizzani M. G. Gallo A. Molinar Min L. Rambozzi P. G. Meneguz 《European Journal of Wildlife Research》2008,54(1):153-156
A 3-year-old male chamois (Rupicapra rupicapra) shot during a harvest plan in Piedmont (Italy) presented periocular alopecic and thickened crusty lesions, some of which
slightly red in colour. Hair still present was broken and easily removed. Direct microscopic examination of the pathological
material collected by skin scraping led to the diagnosis of dermatophytosis, as the hair shafts appeared invaded by unstained
spherical spores (arthroconidia). Fungal growth was obtained by culturing hair and crusts on thiamine/inositol enriched Sabouraud’s
medium at 37°C. The macro- and microscopic characteristics of the organism were typical of the dermatophyte Trichophyton verrucosum. Wild ruminants are rarely affected by dermatophytosis, whereas in cattle, sheep and goats, infection because of this dermatophyte
is quite common. This seems to be the first case of infection by T. verrucosum in chamois. 相似文献
7.
R. O. van Ravenswaay P. R. Henry C. B. Ammerman 《Animal Feed Science and Technology》2001,90(3-4):185-198
Two experiments were conducted to investigate the effects of time and dietary Fe on tissue Fe concentrations following short-term, high level supplementation for use as a bioassay procedure for supplemental Fe sources for ruminants. In Experiment 1, 28 wethers were allotted randomly to four experimental diets which were fed for 15 or 30 days. The basal maize–soyabean meal–cottonseed hulls diet (193 mg kg−1 Fe) was supplemented with 0, 400, 800 or1200 mg kg−1 added Fe from reagent grade ferrous sulfate (FeSO4·7H2O). Iron concentrations in liver, kidney, and spleen increased (P<0.05) as dietary Fe increased; however, muscle, heart, and bone Fe concentrations were unaffected. A logarithmic transformation of liver or kidney Fe concentrations at 30 days regressed on added dietary Fe produced the best fits to a linear model. In Experiment 2, bioavailability of Fe from three feed grade ferrous carbonates known to differ (carbonates A, B, and C) was compared to that from reagent grade ferrous sulfate. The dietary treatments fed for 30 days included the above basal diet (90 mg kg−1 Fe) supplemented with 0, 300, 600 or 900 mg kg−1 added Fe from ferrous sulfate or 600 mg kg−1 Fe from ferrous carbonates A, B, or C. Liver Fe concentrations from sheep fed ferrous sulfate were numerically greater than those of animals fed the carbonate sources or control diet. Kidney Fe concentrations from lambs fed ferrous sulfate at 600 mg kg−1 Fe or carbonate-A were greater (P<0.05) than those fed carbonates B or C. Iron concentrations in spleen were lower (P<0.05) in lambs fed carbonate-B than for those fed 600 mg kg−1 Fe as ferrous sulfate, but were similar to other carbonates. Overall average bioavailability estimates based on multiple regression slope ratios for the three tissues were ferrous sulfate 1.00, carbonate-A 0.55, carbonate-B 0.00, and carbonate-C 0.20. Estimates for carbonates A and C were similar to those based on hemoglobin concentrations reported previously for young swine supplemented at dietary concentrations near the requirement. 相似文献
8.
Richard Ogutu-Ohwayo 《Environmental Biology of Fishes》1990,27(2):81-96
Synopsis There has been a decline, and in some cases an almost total disappearance, of many of the native fish species of lakes Victoria and Kyoga in East Africa since the development of the fisheries of these lakes was initiated at the beginning of this century. The Nile perch, Lates niloticus, a large, voracious predator which was introduced into these lakes about the middle of the century along with several tilapiine species, is thought to have caused the reduction in the stocks of several species. But overfishing and competition between different species also appear to have contributed to this decline. By the time the Nile perch had become well established, stocks of the native tilapiine species had already been reduced by overfishing. The Labeo victorianus fishery had also deteriorated following intensive gillnetting of gravid individuals on breeding migrations. L. niloticus is, however, capable of preying on the species which haven been overfished and could have prevented their stocks from recovering from overfishing. L. niloticus is also directly responsible for the decline in populations of haplochromine cichlids which were abundant in these lakes before the Nile perch became established. Even without predation by Nile perch, it has been shown that the haplochromine cichlids could not have withstood heavy commercial exploitation if a trawl fishery had been established throughout Lake Victoria. Their utilisation for human food has also posed some problems. The abundance of the native tilapiine species may also have been reduced through competition with introduced species which have similar ecological requirements. At present, the Nile perch and one of the introduced tilapiine species, Oreochromis niloticus, form the basis of the fisheries of lakes Victoria and Kyoga.Invited editorial 相似文献
9.
反刍动物取食量及其调节 总被引:5,自引:1,他引:4
反刍动物取食量受动物因素、环境因素和植物因素的影响。取食量的估计可基于5个途径:饲料生物量或动物体重的短期变化; 食道或瘤胃瘘管技术; 食口计数法; 日粪便排出量和消化率的测定; 双链烷技术。取食量的调控机制极为复杂, 任何单因子都很难给予完全的解释。多因子途径将有助于这一问题的解决。中枢神经系统应当作为探索这一课题的重要基础。无论是从生理学、解剖学或行为学的途径, 重要的是寻找和发现中枢神经系统和来自动物体内环境各种信号间的联系, 并且探索建立这种联系的巧妙机制以及这种机制是如何在短期和长期的条件下对取食量加以调控。 相似文献
10.
《Archives of animal nutrition》2013,67(3):271-282
A mathematical model of rumen fermentation processes was validated with 65 sheep experiments and 45 cattle experiments, respectively. Further, it was shown how the modell reacts when the feed composition, the level of feed intake and the feeding frequency was changed. The model predictions were satisfactory for the digestibility of organic matter and neutral detergent fibre (NDF) in rumen, the production of volatile fatty acids and the non‐ammonia‐N (NAN) flow to duodenum. The partition of NAN in microbial and feed N was estimated with lower reliability. The effects of variation of feeding level, feeding frequency and roughage quality (crude protein, lignin) on digestion processes have been simulated correctly. On the other hand, the effects of the proportion of roughage to concentrate have not been reproduced sufficiently with the mechanismes included in the model. To make correct predictions in this area too, it is necessary to integrate the rumen pH and its effects on rumen processes into the model. A mechanistic approach for estimation of the velocity constants for passage of substances out of the rumen would improve the model. 相似文献
11.
《Archives of animal nutrition》2013,67(5):325-334
Abstract This study employed two commercial enzyme preparations to examine the effects of endoglucanase, xylanase or their combination on in vitro volatile fatty acid (VFA) production by ruminal microbial populations. Batch ruminal cultures were established with one of various feedstuffs or with a fescue hay-based diet and ruminal fluid from a heifer fed a 40% forage:60% concentrate diet. Addition of xylanase at 135 xylanase units (XU) per ml increased total VFA production from the fescue hay-based diet (44.3 vs. 57.2 mM, p < 0.05) without changing the acetate to propionate (A:P) ratio. Addition of endoglucanase at 2, 3, 4, and 5 carboxymethyl cellulase units (CMCU) per ml increased total VFA production from the fescue hay-based diet on average by 36% (p < 0.05). Addition of 3, 4 and 5 CMCU/ml also decreased (p < 0.05) the A:P ratio. The combined addition of xylanase (135 XU/ml) and endoglucanase (5 CMCU/ml) increased total VFA production from the fescue hay-based diet (40.9 vs. 61.5 mM, p < 0.05) and reduced the A:P ratio (3.4 vs. 1.5, p < 0.05). The effects of endoglucanase and xylanase supplementation on in vitro VFA production varied across the various substrates used. However, endoglucanase supplementation consistently reduced the A:P ratio with all substrates tested. The effects of the enzyme combination were generally greater than either enzyme alone. We conclude that endoglucanase and xylanase activities differ in their ability to affect ruminal VFA production, and endoglucanase but not xylanase, may improve fermentation efficiency by reducing the A:P ratio. 相似文献
12.
反刍兽源附红细胞体感染小鼠的研究 总被引:14,自引:1,他引:14
目的 采用反刍兽源附红细胞体感染小鼠 ,研究附红细胞体的感染途径及在小鼠体内的消长规律 ,试图建立附红细胞体感染动物模型。方法 经小鼠腹腔、皮下接种含有附红细胞体的奶牛、山羊血液 ,脏器悬液和接触感染。结果 四种接种方法均获成功 ,附红细胞体在小鼠体内呈现一定的规律性。感染后第 8天附红细胞体在小鼠的血液可以查见。感染后第 15~ 18天附红细胞体的感染率达到高峰。感染后第 2 0d附红细胞体逐渐消失。在整个实验过程中未见感染小鼠明显的临床症状。结论 可以用小鼠建立附红细胞体感染动物模型。附红细胞体的感染方式有以下几种 :腹腔、皮下接种、接触感染。 相似文献
13.
The conservation of Himalayan forests is big concern in view of global agenda. Many studies in this endeavor reported that
the rate of forests degradation is posing a severe threat to the landscape and existing biodiversity in the Himalayas. Currently
there many conservation approaches exists and of them four are widely recognized (1) Conservation through traditional religious
beliefs “traditional conserved forests” (TCF); (2) Conservation through governmental planning and schemes “government conserved
forests” (GCF); (3) Conservation through creation of protected areas (PAF); and (4) Conservation through community efforts
“community conserved forests” (CCF). Our hypothesis in this direction says that all the conservation approaches lead to same
results concerning to forest conservation. To testify our hypothesis we have studied the forests of each conservation regimes
and evaluated them based on the identified indicators. We have done empirical studies and following the cloud-free satellite
data were used for last three decades (such as Multi-Spectral Scanner, Linear Imaging and Self Scanning, and Enhanced Thematic
Mapper ) to study a change in vegetation dynamics of the mountain forests in multi-temporal dimension. Our research concluded
that community conservation approach have greater significance for biodiversity conservation and management in the Himalayan
region. Here we support the model of CCF for forest ecosystem conservation, alongside the sustainable livelihood of the mountain
societies. But every conservation regimes has its own importance in viewpoint of the particular objectives. Therefore, we
suggests advancement and revision of PAF and GCF however, some elements of CCF can be introduced in TCF for making up it more
sound in view of rapid socio-economic and cultural changes taking place in the communities.
An erratum to this article can be found at 相似文献
14.
H. J. Breukelman J. J. Beintema E. Confalone C. Costanzo M. P. Sasso A. Carsana M. Palmieri A. Furial 《Journal of molecular evolution》1993,37(1):29-35
Mammalian pancreatic ribonucleases form a family of homologous proteins that has been extensively investigated. The primary structures of these enzymes were used to derive phylogenetic trees. These analyses indicate that the presence of three strictly homologous enzymes in the bovine species (the pancreatic, seminal, and cerebral ribonucleases) is due to gene duplication events which occurred during the evolution of ancestral ruminants.In this paper we present evidence that confirms this finding and that suggests an overall structural conservation of the putative ribonuclease genes in ruminant species.We could also demonstrate that the sequences related to ox ribonuclease coding regions present in genomic DNA of the giraffe species are the orthologues of the bovine genes encoding the three ribonucleases mentioned above.Correspondence to: A. Furia 相似文献
15.
16.
ZHUANG JIAN-YUN 《菌物学报》1986,5(2)
<正> A list of 209 rust species recorded from East Himalaya, southeastern Xizang during a survey in 1982—1983 is given, Among them 15 species are described as new ones and 28 species are new records for China. All speciments are kept in the Herbarium Mycologicum Instituti Micribiologici Academiae Sinicae, Beijing. 相似文献
17.
Martina Carrete José Antonio Sánchez-Zapata José Enrique Martínez Miguel Ángel Sánchez José Francisco Calvo 《Biodiversity and Conservation》2002,11(6):975-985
We investigated three possible causes of territory desertion among Bonelli's eagles Hieraaetus fasciatus in Murcia (southeastern Spain): low demographic parameters, low habitat quality and competition with Golden eagles Aquila chrysaetos. From 1983 to 1997, we surveyed a Bonelli's eagle population. Abandoned and occupied territories were compared to find differences in demographic parameters (flight rate, productivity and mortality) or habitat characteristics. Mortality was significantly higher in abandoned territories. Abandoned territories also had larger areas of forest and extensive agriculture, while occupied territories had more shrublands. Competition with Golden eagles was not a determinant of territorial abandonement but interacted with human persecution of the species. Management implications are discussed. 相似文献
18.
As a result of pioneering work of Hofmann (1973, 1989), nutritional ecologists classify ruminants into three feeding-type categories: browsers (concentrate feeders), grazers, and intermediate or mixed feeders. Hofmann proposed that these feeding types result from evolutionary adaptations in the anatomy of the digestive system and that one consequence is shorter retention of the digesta in the rumen of browsers, and thus a decreased efficiency of fiber digestion relative to that of grazers. We examined the hypotheses that (1) fiber digestion of browsers is lower than that of grazers, (2) salivary gland size is larger in all browsers than in grazers, (3) the browser's larger salivary glands produce larger volumes of thin serous saliva than those of grazers, and (4) thus, browsers have higher liquid passage rates than do grazers. We found that the extent of fiber digestion is not significantly different between browsers and grazers, although fiber digestion is positively related to herbivore size. In general, salivary gland size is approximately 4 times larger in browsers than grazers, but some browsers (e.g., greater kudu) have small, grazer-sized salivary glands. Resting (non-feeding or ruminating) saliva flow rates of mule deer (browser) and domestic sheep and cattle (grazers) were not significantly different from each other. Finally, ruminal liquid flow rates were not different between feeding types. We conclude that many of Hofmann's nutritional and physiological interpretations of anatomical differences amongst ruminants are not supportable. 相似文献
19.
Metagenomics in animal gastrointestinal ecosystem: Potential biotechnological prospects 总被引:1,自引:0,他引:1
Microbial metagenomics---the applications of the genomics suit of technologies to nonculturable microorganisms, is coming of age. These approaches can be used for the screening and identification of nonculturable gastrointestinal (GI) microflora for assessing and exploiting them in nutrition and the health of the host. Advances in technologies designed to access this wealth of genetic information through environmental nucleic acids extraction and analysis have provided the means of overcoming the limitations of conventional culture-dependent microbial genetic exploitation. The molecular techniques and bioinformatics tools will result in reliable insights into the animals' GI microbial structure and activity of the livestock gut microbes in relation to functional interactions, temporal and spatial relationships among different microbial consortia and dietary ingredients. Further developments and applications of these methods promise to provide the opportunity to link distribution and identity of various GI microbes in their natural habitats, and explore their use for promoting livestock health and industrial development. 相似文献
20.
Animal models are of critical importance in biomedical research. Although rodents and lagomorphs are the most commonly used species, larger species are required, especially when surgical approaches or new medical devices have to be evaluated. In particular, in the field of perinatal medicine, they are critical for the evaluation of new pharmacologic treatments and the development of new invasive procedures in fetuses. In some areas, such as developmental genetics, reproductive biotechnologies and metabolic programming, the contribution of ruminants is essential. The current report focuses on some of the most outstanding examples of great biomedical advances carried out with ruminant models in the field of perinatal research. Experiments recently carried in our research unit using ruminants are also briefly described. 相似文献