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61.
在体验经济时代,为游客创造旅游体验记忆至关重要,这种体验后的记忆将会影响旅游者的未来旅游决策。以方特为例,选取网络游记为数据来源,综合运用内容分析法和共现网络法,探索主题公园旅游体验记忆的结构维度,尝试构建主题公园旅游体验记忆构成模型。研究发现:主题公园旅游体验记忆按照游前——游中——游后时间轴,分别包含体验预演和成本估计——城市形象、身份重构、参与涉入、互动交往、配套支持和感知价值——行为意向总计9个维度,并进一步构建主题公园旅游体验记忆构成模型。  相似文献   
62.
许氏平鲉4 个野生群体遗传多样性微卫星分析   总被引:2,自引:0,他引:2  
利用18对微卫星引物分析了荣成湾群体1、荣成湾群体2、即墨群体和龙口群体共4个许氏平鲉(Sebastes schlegeli)野生群体的遗传多样性。结果表明:4个群体的平均有效等位基因数分别为3.1、2.7、2.8和2.7,平均期望杂合度分别为0.590、0.540、0.552和0.491,平均多态信息含量分别为0.577、0.495、0.538和0.528。4个许氏平鲉群体均表现出较高的遗传多样性水平,但也都存在杂合子缺失现象。Χ2检验显示,4个群体中大部分微卫星位点偏离Hardy-Weinberg平衡(P<0.05)。群体间Fst值为0.04,说明遗传变异主要存在于群体内,群体间的遗传分化程度较低。该研究结果将为许氏平鲉种质资源保护和合理利用以及人工增殖提供理论参考。  相似文献   
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Wild reindeer are under pressure from human development projects throughout their habitat. Norway is currently making a significant move to establish a new management model based on national reindeer regions and regional management plans. A focus on wild reindeer as a flagship species allows the species to be included as a broad conservation objective in complex land-use plans. The authors surveyed a representative sample of residents in the Rondane and Setesdal regions to examine their perceptions of the current status of reindeer and how management relates to other social and development issues. Local actors and institutions, including hunters, were perceived as more responsible and suited to make decisions about reindeer population sizes and management objectives than non-local actors. There was little local consensus on the role of human impacts on wild reindeer, and residents rated local knowledge higher than scientific knowledge for management purposes. Rondane residents attached more importance to reindeer than Setesdal residents, but the latter saw reindeer as more threatened by human development. New management approaches will need to take a social-ecological perspective and recognize that the inclusion of reindeer can enhance broader conservation goals at regional, national, and international levels, but may also escalate local social conflicts.  相似文献   
64.
为了评估长牡蛎(Crassostrea gigas) 2个壳长性状(掌心形)快速生长选育群体(LY2-K4、LY2-K7)、1个壳高性状(速生型)快速生长选育群体(LY2-K11)和6个野生群体(QHD、LS、HD、ZH、WD、KTD)的遗传多样性和遗传结构, 用21对多态性丰富的微卫星引物对9个长牡蛎群体的269个个体进行了遗传分析。结果显示: 21个微卫星位点共检测出了460个等位基因(Na),平均等位基因数为21.905; 21个微卫星位点的多态信息含量(PIC)均大于0.5, 具有高度遗传多态性; 选育群体LY2-K11的遗传多样性最低(Na=13, I=2.128,He=0.831, PIC=0.825), 野生群体KTD的遗传多样性最高(Na=29,I=3.112, He=0.941, PIC=0. 938); 189个群体位点组合有66%偏离哈代-温伯格平衡, 表明这些群体存在一定程度的杂合子缺失; 9个群体间的遗传分化指数(Fst)为0.012~0.064, 处于较低的遗传分化水平; AMOVA分析显示遗传变异主要来自于个体内; PCoA分析结果与UPGMA聚类树一致, LY2-K11群体单独聚为一类, QHD和HD群体聚为一类, 其他6个群体聚为一类。综上所述, 长牡蛎3个选育群体和6个野生群体遗传多样性均较高, 遗传分化水平较低; 选育群体LY2-K11多样性略有下降, 选育过程中应保证亲本的数量及质量, 防止因近交衰退造成遗传多样性降低, 苗种抗逆性变差。该结果将为长牡蛎新品种的选育和野生种质资源的保护提供科学指导。  相似文献   
65.
Among the main invasive species, the wild boar (Sus scrofa) is the most responsible for soil degradation in Europe and many Italian regions. At the same time, the stable presence of this species in agricultural areas has induced a conflict with humans, causing economic losses, environmental degradation and also social issues. A clear quantification of the potential damages (in terms of soil bioturbation) of this species at large scale is, however, still obscure. The purpose of this research is to analyse the role of wild boars as a geomorphologic agent, presenting a general diagnostic framework regarding the geomorphic impact of this species, classifying and mapping potential sediment hotspots and their likely connection to rivers and road networks. Accordingly, a record of wild boar damage types is first presented, and their possible interaction with hydrological and geomorphological processes is described. Then, a pilot case study is discussed on mapping and quantifying wild boar damages in a hilly agricultural landscape located in northeast Italy. The wild boar damages were geolocalized using a geographical positioning system (GPS) in two years of intensive field campaigns among agricultural fields involved in wild boar damaging activities. For each damaged area (total 406), several measures of soil erosion depth were taken and the degradation surface of interest mapped for a total of 10 150 measures. The volume of removed soil was then estimated, considering the average depth of damages previously recorded. Finally, the Index of Connectivity was applied to provide a classification of the considered damages based on their connection to both river and road networks. The results indicate that the ongoing uncontrolled wild boar expansion may not affect crops only or be a risk for people, but can also increase soil erosion, with a potential connection to hydrographic networks and human infrastructures. © 2019 John Wiley & Sons, Ltd.  相似文献   
66.
该文阐述建立中华(成都)大熊猫野生动物园的必要性和可行性.该工程的完成将能承担接纳成都大熊猫繁育基地人工繁养的大熊猫回归大自然.在自然保护区外围区适度开展生态旅游,将有利于自然保护区的可持续发展.  相似文献   
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养殖对虾和海捕对虾肌肉一般组成的分析结果表明:两类对虾肌肉中各组分含量无显著差异。两类对虾肌肉提取物中游离氨基酸主要有Gly,Arg,Ala,Pro,Tau。提取物水解后,Asp和Glu量增加8—10倍说明提取物中有短肽存在。提取物中主要核苷酸是AMP和IMP两类对虾提取物中的氧化三甲胺和甜菜碱含量相差较大。  相似文献   
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