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71.
湖北白龙洞古人类遗址是中国较有影响的更新世中期古人类遗址之一。本项工作通过使用日本宾得公司产RS-202N免棱镜型全站仪及美国Autodesk公司产AutoCAD2006计算机软件等,实地采集白龙洞遗址地貌和洞穴形态三维数据,使用计算机建立起遗址地貌数字模型和洞穴居址数字模型。通过数字模型进行多视角观察、分析,认识到这种方法可以实现以三维空间的形式保存和处理多种考古遗存信息,能够提供古人类遗址三维动态的观察视角,以及提供多种用途的遗址三维分析数据和考古专题图等。白龙洞遗址数字模型的测量和观察分析认识到,白龙洞遗址古人类(直立人)具有对洞穴高效开发利用的能力,并且具有在洞穴空间较为高大的区域集中活动的特点;  还可能具有在洞穴内部使用火进行照明的行为;  在居址选择上,白龙洞古人类已经具备对低山地区复杂地貌、开阔视野、干燥居址与近水环境,以及石料集中地和多元食物生境的适应性选择。此外,分析工作还显示洞穴遗址内部堆积物,除古人类活动遗留外,其他土状堆积物的来源可能来自于洞穴内部裂隙。白龙洞遗址数字模型的建立与初步分析,是国内将三维数字模型技术应用于古人类遗址研究的首次尝试。该方法对于获取更多遗址研究信息和多学科综合研究古人类遗址具有重要作用。  相似文献   
72.
王强  崔军茹  崔璨  古恒宇 《地理科学》2022,42(8):1381-1390
基于2016年中国流动人口动态监测数据,运用多尺度地理加权回归模型对流动人口流入地购房意愿影响因素的空间异质性进行分析。研究发现:① 中国流动人口在流入地城市的购房意愿整体偏低,尤其在流动人口聚集的东南沿海地区,流动人口购房意愿最低。② 多尺度地理加权回归(multi-scale geographically weighted regression,MGWR)模型能识别出不同因素对购房意愿的影响具有空间尺度差异,其中户口类型、流动范围、流动次数等显著变量对不同区域流动人口购房意愿的影响存在明显的区域差异。③ 各影响因素呈现显著的空间分异格局,其中婚姻状况、户口类型、职业类型、房价、公共服务等因素对东南地区购房意愿的影响较大,收入、流动次数、已购住房、随迁子女等因素对东北地区购房意愿的影响更大,西北地区平均受教育年限和拥有住房公积金对流动人口购房意愿的正向促进作用显著,而跨省流动的负向影响由西北向中部地区梯度递减。  相似文献   
73.
流动背景下,传统固定的家不断受到挑战,家的定义和内涵也因流动而更加丰富。现有研究多从陆地视角关注流动对家的多维影响,较少探讨海洋语境下流动与家的潜在联系。此外,随着科技的进步,生产空间“家”的营建也成为可能。文章借鉴家的地理学相关理论,基于深入访谈、参与式观察和文本分析等方法,探讨海南潭门渔民在南海耕海实践中生产空间家的营建和情感体验。研究发现,潭门渔民在流动渔船中利用类“家”的功能进行日常生活实践,从而模糊渔船生产空间与家的边界,产生“在家”的体验;在长期的耕海过程中,渔民之间通过彼此之间的关心、照顾、互助等行为增进感情,从而产生家的团结、温暖等情感体验;渔船在长期的海上流动过程中,渔民逐渐对南海的岛礁、物产、边界等自然、人文环境产生熟悉感、安全感和归属感等情感体验,实现了对南海“祖宗海”的家园想象。  相似文献   
74.
This study assessed the role of the Pondoland Marine Protected Area (MPA) in the Eastern Cape province of South Africa by evaluating retention versus ‘spillover’ of exploited fishery species that were tagged in a 400 km2 no-take zone of the MPA. From April 2006 to July 2010, 2 124 fish comprising 36 species were tagged in the MPA, with an overall recapture rate of 23%. Findings for four important species (Polysteganus praeorbitalis, Chrysoblephus puniceus, Epinephelus andersoni and Epinephelus marginatus) are presented. Recapture rates ranged from 8% to 60% and time-at-liberty from 0 to 1 390 d. Individuals of all four species displayed highly localised station-keeping behaviour. For all four species, the 95th percentile of intra-study site movements was <750 m (linear distance) and many recaptures were within 250 m of the release site, showing that some fish spend most of their time in the MPA's no-take zone. However, some fish moved beyond the boundary of this zone in a north-easterly direction (range 3–1 059 km), where they would be available to the boat-based fishery in KwaZulu-Natal. The combination of resident individuals with some with ranging behaviour suggests that the MPA can provide a conservation role for these species, while exporting some individuals into nearby fisheries.  相似文献   
75.
Using ultrasonic telemetry, we measured the distance of attraction to a baited trap and then used this value to calculate the “area of bait influence”. This value, along with the mean daily home range for the same animals, was used to calculate the “trapping area” of an individual trap. Lobsters (n = 25) were tracked inside a large underwater mesocosm containing a single baited lobster trap. During the study, 14 of the 25 lobsters approached the trap from a mean (+SEM) distance of 11.0 ± 0.7 m. Using this distance as the radius of a circle, the resulting circular area of bait influence was 380 m2. The movements of 18 lobsters were used to calculate a mean daily home range of 1002.4 ± 195.7 m2. The radius of a circle with this area (17.8 m) was then combined with the mean distance of bait attraction to calculate the trapping area, defined as: the total area from which the catch is drawn (2604.0 m2; a circle with a radius of 28.8 m or 17.8 m + 11.0 m). A demonstration of the potential use of empirical data about lobster home ranges, trap dynamics and area of bait influence to improve our understanding of the relationship between the density of lobsters on the bottom and catch is included.  相似文献   
76.
Photo‐identification has been established as a helpful tool in cetacean research. However, no study to date has attempted to apply this method to short‐beaked common dolphins (Delphinus delphis L.). We present here the results of two studies that were conducted concurrently in Mercury Bay and the Hauraki Gulf on the north‐east coast of New Zealand's North Island. Methods for distinguishing between individual dolphins are discussed. Sighting records of recognisable individuals indicate that some common dolphins move between Mercury Bay and the Hauraki Gulf (100 km distance), as well as between Mercury Bay and Whakatane (200 km distance). Common dolphin abundance and site fidelity appeared to be greater in the Hauraki Gulf than in Mercury Bay. A selection of photographs of distinct individuals is presented to allow future studies to compare their sighting records to ours, which may help establish the extent of home ranges, site fidelity, and possibly even longevity for common dolphins.  相似文献   
77.
国内外生态用地理论研究与实践探索   总被引:1,自引:0,他引:1  
生态用地的理论研究与实践探索对于我国建设生态文明、促进经济社会发展与生态环境相协调具有重要意义。本文对国内外生态用地的理论研究成果与实际管理工作进行了归纳综述,在探讨生态用地内涵与范围的基础上,分析总结了我国与其他国家的相关工作,并对我国今后生态用地管理提出了建议。  相似文献   
78.
As land use change continues to increase throughout the Amazon basin, there is a pressing need to accurately map, quantify and assess the effects of different factors on forest cover change (FCC). Land tenure may sometimes have important effects on forest cover, yet such effects remain poorly understood in Amazonia, particularly outside Brazil. In this paper we assess whether significant differences in trends of FCC can be partially explained by different land tenure arrangements, using a case study in southwestern Beni (Bolivian Amazon). We examine spatio-temporal dynamics of FCC across four land tenure systems (indigenous titled territory, protected area, logging concession, and private land) by classifying forests using a time-series of Landsat satellite imagery consisting of four dates (1986, 1996, 2001, 2009). Specifically, we unravel (1) trends in early growth and old-growth forest extent, including changes in total cover area, annual change rates, and spatial change dynamics, and (2) trends in old-growth forest fragmentation. To better understand the association between land tenure and FCC, we qualitatively assess the potential role that other underlying and proximate drivers may have had in FCC over the study period. We found that private lands underwent, by far, the largest FCC, that indigenous territories and the protected area had little FCC, and that logging concessions were responsible for the lowest FCC. Our findings suggest that land tenure played a key role in FCC except in private areas, where many other drivers had operated. Our study sheds light into the potential role of land tenure in FCC and has important implications for public policies aimed at socioeconomic development and environmental conservation in the Amazon. We give some policy recommendations drawn from a biocultural conservation perspective that could contribute to implement more inclusive conservation policies in the region.  相似文献   
79.
Immigrant–native segregation is present in the spaces in which individuals from different ethnic/racial groups practice their everyday lives; interact with others and develop their ethnic, social and spatial networks. The overwhelming majority of academic research on immigrant segregation has focused on the residential domain, thus largely overlooking other arenas of daily interaction. The present study contributes to the emerging literature on immigrant residential and workplace segregation by examining changes in patterns of residential and workplace segregation over time. We draw our data from the Stockholm metropolitan region, Sweden’s main port of entry for immigrants. The results suggest a close association between residential and workplace segregation. Immigrant groups that are more segregated at home are also more segregated in workplace neighborhoods. More importantly, we found that a changing segregation level in one domain tends to involve a similar trend in the other domain.  相似文献   
80.
《Urban geography》2013,34(6):536-557
Although much has been written about the abstract spaces of homelessness, relatively less has been documented on how the architecture of homeless shelters intersects with the homeless experience. Emergency shelters are the first places where homeless families begin their journey toward becoming "homed." Studies suggest that there is a middle-class bias in the design of emergency homeless shelters, but how do its spaces contribute to the route out of homelessness? Through narratives of homeless families, and observations of the places they occupy in an emergency shelter in Arizona, this article illustrates how they engage with the shelter's architecture to construct notions of home and homelessness. This study suggests that while homeless families try to achieve the psychological qualities of a "home" in the shelter, the materiality of the places in the shelter, where these qualities are acquired or negotiated, become important symbolic markers to becoming "homed."  相似文献   
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