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101.
南岳自然保护区素为天下名山,层峦叠翠,风光旖旎,灵动俊秀的自然景观,源远流长的宗教文化,古朴神奇的历史遗迹,形成了博大精深的旅游资源.我国加入WTO后,随着世界旅游业的蓬勃发展,一个全新的旅游分支文化旅游正呈现出迅猛的发展势头.南岳作为素有文明奥区之称,进行文化资源的调查,构筑系统的旅游文化体系,开拓旅游市场,提升旅游品位,做好保护与利用旅游资源这篇文章有着重要意义.  相似文献   
102.
The allocation to growth, defense and reproduction varies in social insects within a species' life cycle and between species. A life cycle model (Oster and Wilson 1978) generally failed to predict caste allocation in small litter-nesting colonies of Neotropical Pheidole. Two of its assumptions were often invalid: food was unlikely to be limiting in four of five populations, and sexual biomass production accelerated, not decelerated, with colony size in three of five populations. One of five Pheidole populations studied had higher caste ratios (soldiers /workers) in reproductive colonies as predicted, and in no species did caste functions conform to predictions. We also adapted three models from plant defense theory to study between-species patterns of caste allocation. Among 12 litter Pheidole the amount of sterile biomass devoted to soldiers varied from 18 to 62%. Queen size, growth rate, and soldier investment positively covaried. Only one model, the cost of replacement hypothesis (McKey 1979), correctly predicted that species with costly female alates invest more in defense. The two hypotheses linking apparency to defense may also be valid if fast-growing colonies are more likely to attract the attention of predators.  相似文献   
103.
ABSTRACT

Land-use conflict has become a topical issue due to an increase in the number of stakeholders having incompatible interests related to particular land uses. Competing land-uses include those for conservation, irrigation, game and livestock farming, settlements and mining. These groupings of land-uses have different interests and objectives. This study aims to investigate the basis for the land-use conflict, and to get insights into how various stakeholders perceive and interpret existing conflicts. Empirical results were drawn from observation, interviews and documents collected between 2011 and 2018. The interviews were held with various stakeholders involved in land-use decisions. Qualitative data were analysed through thematic content analysis, and observations assisted with the corroboration of information collected through interviews. The study recorded four central land-use conflicts: irrigation farming with conservation; game farming with conservation; settlements/livestock farming with conservation; and mining with conservation/game farming/irrigation farming. The study also explains how local stakeholders understand these conflicts.  相似文献   
104.
Intermittent breeding (skipping a breeding season) can be the result of an adaptive decision by a focal individual, trading current reproductive success in favour of future reproductive success (residual reproductive value hypothesis). In contrast, an individual can also be forced by conspecifics to abandon the familiar breeding site and refrain from breeding due to lack of suitable alternative breeding sites or mates (competition hypothesis). I studied intermittent breeding in the territorial and site-faithful Eurasian oystercatcher Haematopus ostralegus, using a dataset covering 20 years. Intermittent breeding (in total 86 cases) occurred among breeders that formerly bred in high- as well as low-quality territories. The main factor associated with intermittent breeding in high-quality sites was death of a mate, while in low quality sites divorce was the most prominent factor. In 93% of the cases birds were forced to cease breeding due to pressure from conspecifics consistent with the competition hypothesis. There was no association between intermittent breeding and promotion to a territory of better quality. Instead, oystercatchers returned to breeding habitat of similar quality and at a very close distance (median distance 128 m) from the previous breeding location. Breeding absences lasted on average 2.4 years, with a maximum of 9 years, and the quality of the territory obtained after the absence varied with the duration of it. Birds who re-bred in a high-quality territory acquired this on average faster than those that re-bred in a low-quality territory, indicating that birds in high-quality sites are better competitors.  相似文献   
105.
南岳宗教文化历史悠久,最早进入南岳的宗教是中国土生土长的道教,据史载,西汉时道家就在南岳活动,到东汉时道教天师张道陵从天目山来南岳谒青玉坛和祭祀祝融神后,道教正式进入南岳活动,约在两晋南北朝时期,佛道传入南岳,至今已有1700年历史;佛道两家虽然信仰不同,追求各异,但友好相处,佛、道共存一山,共荣一庙(南岳庙),佛道共荣的宗教文化尤为国内外宗教名山所罕见,极盛时期,有宫观41所,佛寺150所;基督教于清末传入南岳,也有一定影响,南岳宗教文化的表现形式有:香期、庙会.  相似文献   
106.
Ammophila arenaria (marram grass) was introduced to South Africa from Europe as a means of stabilizing the Cape Flats in the 1870s, but was only successfully established in the 1890s as it was found that seeds from the first introductions did not readily germinate. By the end of the last century, it was successfully used as a dune stabilizing grass. It is now widely used in stabilization projects along the Cape coastline, being established by planting cuttings or whole plants. Because of problems experienced of marram becoming invasive, especially on the west coast of North America, and the fact that we have many invasive species which threaten our indigenous dune fields, studies have been initiated on this plant in South Africa. Most work to date has involved investigating the methods used to establish the plant in stabilization sites, and very little has been done on the biology of the species in this country. Marram is generally thought not to seed in South Africa, and thus its spread has been limited. However, in the light of recent reports of successful germination of the seed, detailed studies on the phenology of seed production and establishment in natural areas will be undertaken. Studies on the natural control by fungal species and nematodes will be carried out in conjunction with work done in the Netherlands, so that a comparison of the biology of the species in South Africa can be made with that in Europe, where it is used extensively to stabilize dunes. Nomenclature: Arnold & de Wet (1993) for vascular plants.  相似文献   
107.
We tested several predictions of nest defense theory by observing variation in flushing distance and probability of nest abandonment within and between six species of waterfowl. In these species, only the females incubate eggs and attend offspring. First, we examined whether flushing distance by females varied in relation to clutch size, stage of incubation, and time of season, after controlling for the number of visits made to nests by observers. Revisits by observers appeared to affect flushing distance by females for reasons unrelated to the relative value of the current clutch. We found that as incubation progressed, females allowed observers to approach more closely before flushing from the nest. In some species, females with larger clutches allowed closer approaches to nests before flushing which was also consistent with nest defense theory. In contrast, time of season (Julian date) did not relate to flushing distance for any species. When species were compared, we found that species with moderate to high yearly mortality and high reproductive output per breeding attempt (e.g., northern shoveler and blue-winged teal) were less likely to abandon nesting attempts and exhibited riskier behavior (remained at nests when approached closely by observers) than species that had lower yearly mortality (e.g., mallard). Our results show that flushing distance and patterns of nest abandonment by female ducks conform to several predictions of nest defense theory.Correspondence to: M.R.L. Forbes  相似文献   
108.
Global warming mitigation calculationsrequire consistent procedures for handlingtime in order to compare `permanent' gainsfrom energy-sector mitigation options with`impermanent' gains from many forest-sectoroptions. A critical part of carbonaccounting methodologies such as thosebased on `ton-years' (the product of thenumber of tons of carbon times the numberof years that each ton is held out of theatmosphere) is definition of a timehorizon, or the time period over whichcarbon impacts and benefits are considered. Here a case is made for using a timehorizon of 100 years. This choice avoidsdistortions created by much longer timehorizons that would lead to decisionsinconsistent with societal behavior inother spheres; it also avoids a rapidincrease in the implied value of time ifhorizons shorter than 100 years are used.Selection of a time horizon affectsdecisions on financial mechanisms andcarbon credit. Simple adaptations canallow a time horizon to be specified andused to calculate mitigation benefits andat the same time reserve a given percentageof weight in decision making forgenerations beyond the end of the timehorizon. The choice of a time horizon willheavily influence whether mitigationoptions such as avoided deforestation areconsidered viable.  相似文献   
109.
Should forest-based climate mitigationmeasures be approved for crediting through the CleanDevelopment Mechanism (CDM), they could offer anopportunity to accomplish three important objectives:cost-effective reductions in carbon emissions andsequestration of atmospheric carbon; conservation andrestoration of forests and their biological diversity;and, the assistance of host countries and communitiesin their socioeconomic development. However,prospective investors in CDM projects, host countriesand other CDM `stakeholders' might be expected toplace widely different priorities on achieving theseobjectives. This paper describes several factors thatwill affect investor interest in CDM projects, thecharacteristics of forest-based CDM projects that willattract investments, and an approach to identifyingprojects that meet the key objectives of multiplestakeholders. This approach entails identifyingsites, such as degraded watersheds, where CDMfinancing for forest conservation and restoration cangenerate readily monetizable local and regionalsocioeconomic benefits, while mitigating carbonemissions in forests with importance for conservingbiodiversity.  相似文献   
110.
昆仑山区构造区划初探   总被引:29,自引:0,他引:29  
青藏高原虽然经过了多次考察,已经基本摸清了高原的构造格架,然而高原西北部的昆仑山—喀喇昆仑山地区的构造区划仍很不明确。经过这次考察,获得了大量新资料;新发现了库地-苏巴什为一条独立的更早阶段的重要构造界线。考察发现麻札-康西瓦-木孜塔格构造带与东面的昆仑山口-玛沁构造带相联,是真正原第四缝合带所指。由以上这两条构造带把昆仑山分成了北带、中带与南带3部分,而南带从构造发育历史看它与可可西里-巴颜喀喇区相联,不属于真正的昆仑构造区。  相似文献   
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