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1.
麻学锋  赵洁 《生态学报》2023,43(24):10454-10463
在人与自然和谐共生的战略背景下,旅游城市生态建设是推动居民福祉持续提升的重要引擎。厘清旅游城市生态建设提升居民福祉的实现机理,以张家界市为例,利用ARMA模型检验二者关系,并运用结构方程模型明确提升路径。研究发现:(1)张家界市生态建设水平呈现波动上升趋势,而居民福祉水平大致呈现先下降后上升的“勺型”发展态势。(2)旅游城市积极加快生态建设有利于显著提升居民福祉,作用路径包括体现一般城市共性的产业升级和城镇化建设,以及凸显旅游城市特性的旅游发展和就业增长。(3)旅游城市生态建设提升居民福祉的路径优化策略,一是统筹提高城镇化质量,健全利益共享机制;二是激励企业绿色创新,推动产业转型升级;三是促进文旅融合发展,保障旅游就业质量。研究有利于强化生态文明建设战略的实践指导,也为旅游城市发挥生态优势增进民生福祉提供科学依据。  相似文献   

2.
张惠婷  王宏卫  雷军  张飞  王正伟  谈波  高一薄 《生态学报》2021,41(11):4393-4405
基于共生理论,选取乌鲁木齐市、五家渠市、昌吉市为研究案例区,构建"三生"空间评价指标体系及"三生"功能评价指标体系,探讨乌五昌地区"三生"空间时空分异格局,借助共生度模型,识别兵团城市与地方城市"三生"功能共生发展模式,并对兵地城市跨界融合发展提供理论建议。结果表明:(1)研究区生产和生活空间面积呈上升趋势,生态空间面积呈下降趋势。(2)在生产功能方面,五家渠市与乌鲁木齐市、昌吉市共生模式分别为正向非对称共生、反向非对称共生,生活功能与生态功能方面,均为正向非对称共生,各功能城市间影响程度不同。(3)基于"三生"空间格局及"三生"功能共生模式,提出兵地融合发展建议,生产方面建立四区,三轴,一基地,生活方面加强交通路网建设,生态方面兵地协同建立生态保护区。  相似文献   

3.
Metropolitan sporting, and particularly football, competitions were established in all of Australia's colonial state capital cities about a century ago. Typically, they were comprised of teams from and were supported by the inhabitants of working‐class, inner suburbs. These competitions were the primary foci of Australians' sporting interest and loyalty for almost a century. But, with the shift of public attention and private capital to national competitions, the former stadia of many local clubs have become redundant spaces in what are now gentrifying inner suburbs. Simultaneously new, and even old, national league teams have sought larger, more modern (near) city centre venues for their operations. In this context, two new national league teams in Perth—Fremantle Dockers and Perth Glory—have experienced considerable challenges in establishing both physical ‘homes’ and local identities. These have included both the supplanting of traditional local clubs and the placating of new kinds of inner suburban residents.  相似文献   

4.
How do material conditions, urban life strategies, and postcolonial medical infrastructures shape the practices of care available to patients and families in Maputo? How do global health interventions articulate with urban economies, colonial legacies, and gendered relations? Under what conditions is health made available in Mozambique's capital? This article explores these questions through the experiences of one young woman as she moves through clinical and city spaces and through changing familial and residential situations. Showing how health is shaped by gendered relations and material circumstances (or condições) as they are refracted through urban space, her experiences make clear that care both requires and creates complex material‐relational conditions rooted in clinic practice, urban forms, and gendered social and familial life. In the midst of complex medical regimes and rapidly changing urban spaces, these conditions constitute the ground on which women access medicine but also give rise to exclusions from forms of care produced by both biomedicine and social relations. Arguing for greater attention to the role of gender, urban space, economy, and exchange in theorizing health in situated urban and transnational spaces, this article advocates for accounts that go beyond biomedical and clinical framings of life, health, and well‐being and that centre relational accounts of life in the city.  相似文献   

5.
The genetic structure of 31 populations of the German cockroach, Blattella germanica (L.), located in two French cities 900 km apart, was estimated by enzyme gel electrophoresis. A set of 41 loci was analysed. Eight loci (4 Est, 3 Lap and 1 Got) were polymorphic. Diversity was estimated at different geographical levels: the overall population, between cities and within a city. Hierarchical F-statistics indicated significant genetic differentiation between all populations and among populations within each city, but no differentiation between cities. FST values for populations within each city and for the overall sample were substantially dissimilar. In addition, a cluster analysis did not separate populations according to their geographical origin but according to the predominance of either of the two alternative Est-4 alleles. The results of this analysis point to the absence of genetic differentiation on a large geographical scale: no large-scale geographical distance effect was detected. However, we evidenced strong genetic substructuring on a local scale, within cities.  相似文献   

6.
As circumstances of conquest change, leaders of empires must adapt their colonial strategies in order to be successful. One example of such modification in approach is the shift from Middle Kingdom to New Kingdom Egyptian colonial activities in Nubia. During the Middle Kingdom (2050-1650 BC) Egypt used aggressive military campaigns to subdue the strong Nubian polity at Kerma, resulting in the construction of fortresses and many victory stelae. In the subsequent New Kingdom period (1550-1050 BC) during which the Egyptian administration succeeded in occupying nearly all of Nubia, changes were necessary in conquest strategies. Diplomacy and cooperation may have replaced military action as mechanisms of control. This article investigates changes in imperial policy through the examination of traumatic injuries in human skeletal remains. Patterns of injuries in a sample from the site of Tombos, an Egyptian colonial cemetery in Nubia dating to the New Kingdom period, are compared with data on the patterns of injuries from Kerma, a cemetery dating to the Middle Kingdom period, published by Judd (2004). Analysis indicates a decrease in the level of traumatic injuries from Kerma to Tombos supporting the idea that through time the Egyptian administration modified their colonial strategy toward more nonviolent means. This article presents data on differences in the patterns of injury at Tombos and Kerma and explores possible explanations for this variation.  相似文献   

7.
郭慧文  严力蛟 《生态学报》2016,36(14):4288-4297
综合应用城市发展指数(CDI)和生态足迹(EF)指标,分析各直辖市1978—2012年的可持续发展情况,衡量发展方式由资源消耗型向环境友好型转变的程度。研究表明:各直辖市的CDI不断增长,至2012年均达到80左右,基本处于同一层次水平,城市经济社会发展状况总体良好。EF的动态变化呈现阶段性发展的特点,各直辖市间也存在显著差异,除上海市,其他3个直辖市的EF呈现增长态势,至2012年,北京EF最高(2.60 hm2/人),重庆最低(1.79 hm~2/人),是唯一一个低于全国平均EF的直辖市。综合分析CDI和EF,在相似的社会经济发展水平下,重庆市的资源消耗较低,可持续发展潜力较大;天津市一直处于资源消耗型发展中,亟待转型;近十年来,上海和北京的城市建设模式出现了一定转变,由以消耗环境资源为代价的发展模式转变为环境友好型的发展模式。  相似文献   

8.
Populations of sturgeon (Acipenseridae) have experienced global declines, and in some cases extirpation, during the past century. In the current era of climate change and over-harvesting of fishery resources, climate models, based on uncertain boundary conditions, are being used to predict future effects on the Earth''s biota. A collection of approximately 400-year-old Atlantic sturgeon spines from a midden in colonial Jamestown, VA, USA, allowed us to compare the age structure and growth rate for a pre-industrial population during a ‘mini-ice age’ with samples collected from the modern population in the same reach of the James River. Compared with modern fish, the colonial population was characterized by larger and older individuals and exhibited significantly slower growth rates, which were comparable with modern populations at higher latitudes of North America. These results may relate to higher population densities and/or colder water temperatures during colonial times.  相似文献   

9.
This article seeks to identify “Greeks” and “non‐Greeks” in “mixed” mortuary contexts in a Greek colony. Specifically, we test the hypothesis that Illyrian and Greek individuals lived and were buried together at the Corinthian colony of Apollonia, Albania (established ca. 600 BC). The pattern of human biological interaction at Apollonia is tested by identifying variation in genetic relatedness using biodistance analysis of dental and cranial nonmetric traits for three sites: Apollonia (n = 116), its founder‐city Corinth (n = 69), and Lofkënd (n = 108), an inland site near Apollonia pre‐dating colonization. Logistic regression analysis estimates that individuals from colonial Apollonia are most closely related to prehistoric Illyrian populations (from Lofkënd and prehistoric Apollonia), rather than Greeks (from Corinth). The phenotypic similarity between colonial Apollonia and prehistoric Illyria suggests that there was a large Illyrian contribution to the gene pool at the colony of Apollonia. However, some trait combinations show low biological distances among all groups, suggesting homogeneity among Illyrian and Greek populations (assessed through pseudo‐Mahalanobis' D2). The degree of phenotypic similarity suggests shared ancestry and long‐term migration throughout these regions. The impacts of missing data and small sample sizes are also considered. Am J Phys Anthropol 153:236–248, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

10.
With growing urbanization, it is becoming increasingly important to design cities in a manner that sustains and enhances biodiversity and ecosystem services. Native bees are critical pollinators that have experienced substantive declines over the past several decades. These declines have captured the attention of the public, particularly urbanites, prompting a large interest in protecting pollinators and their habitats in cities across North America and Europe. Unfortunately, we currently lack research about specific features of urban environments that can enhance the fitness of pollinators. We carried out an intensive study of Bombus impatiens, the Common Eastern Bumblebee, in the city of Toronto (Canada''s largest city), to better understand landscape parameters that provide high‐quality habitat for this species and likely other generalist bees. We divided the city into 270 grid cells and sampled a large number of worker bees, which were then genotyped at twelve hypervariable microsatellite loci. The genetic data allowed us to quantify the effective number of colonies and foraging distance for bumblebees in our study area. We then asked how the city''s landscape and human population demography and income are associated with the availability of high‐quality habitat for B. impatiens. Several aspects of Toronto''s landscape influenced colony density and foraging range. Urbanization had a clear effect on both colony density and foraging distance of workers. On the other hand, functional (i.e., not cosmetic) green space was often associated with higher quality habitats for bumblebees. Our study suggests several planning strategies to enhance habitat quality for bumblebees and other pollinators in cities.  相似文献   

11.
Although trees comprise a primary component of terrestrial species richness, the drivers and temporal scale of divergence in trees remain poorly understood. We examined the landscape-dominant tree, Metrosideros polymorpha, for variation at nine microsatellite loci across 23 populations on young Hawai''i Island, sampling each of the island''s five varieties throughout its full geographic range. For four varieties, principal coordinate analysis revealed strong clustering of populations by variety across the 10 430 km2 island, indicating partitioning of the species into multiple evolutionarily significant units. The single island-endemic form, riparian var. newellii, showed especially strong differentiation from other varieties despite occurring in sympatry with other varieties and likely evolved from a bog form on the oldest volcano, Kohala, within the past 500 000 years. Along with comparable riparian forms on other Pacific Islands, var. newellii appears to represent parallel incipient ecological speciation within Metrosideros. Greater genetic distance among the more common varieties on the oldest volcano and an inverse relationship between allelic diversity and substrate age appear consistent with colonization of Hawai''i Island by older, partially diverged varieties followed by increased hybridization among varieties on younger volcanoes. This study demonstrates that broad population-level sampling is required to uncover patterns of diversification within a ubiquitous and long-lived tree species. Hawaiian Metrosideros appears to be a case of incipient radiation in trees and thus should be useful for studies of divergence and the evolution of reproductive isolating barriers at the early stages of speciation.  相似文献   

12.
Melissa L. Caldwell 《Ethnos》2013,78(3):295-319
In this article I consider how Muscovites cultivate and express nationalist sentiments through their food choices. During the last ten years of the post-socialist transition, Russian consumers have encountered an expanding and increasingly transnational commodity market. Locally produced elements of Russian cuisine both compete with and imitate foreign food products. In response to perceptions that foreign cultures are displacing or subsuming local cultural forms, Russian officials have launched a 'Buy Russian' campaign. Domestic food producers, store clerks, and customers collaborate to classify foods and other products as either 'Ours'(Nash) or 'Not Ours' (Ne nash) and describe local goods as superior to foreign goods in terms of taste, quality, and healthfulness. In their own narratives about consumption choices, Muscovites echo these nationalist themes by explicitly linking their personal food experiences with broader political issues. Drawing from ethnographic fieldwork on foodpractices in Moscow(1995-2001), I suggest that consumption strategies mediate Muscovites' experiences with growing nationalist sentiments in the context of a globalizing Russia.  相似文献   

13.
塔里木河流域相对资源承载力   总被引:8,自引:2,他引:6  
基于改进的相对资源承载力模型,计算2000-2011年塔里木河流域的相对资源人口承载力和相对资源经济承载力,并探讨塔河流域42个县市相对资源承载力的演变规律及空间差异。研究表明:(1)改进的相对资源承载力模型具有一定的研究价值,对于拓宽相对资源承载力评价模型的应用具有实践意义。(2)以新疆为参照区,塔河流域2000-2011年处于人口严重超载、经济非常富余或富余阶段。(3)与全疆相比,土地资源是塔河流域的相对优势资源,水资源是制约塔河流域人口、经济发展的相对劣势资源。(4)以塔河流域为参照区,流域内42个县市的相对资源人口承载力和相对资源经济承载力的空间差异显著。(4)依据相对资源人口、经济承载力的超载、富余状态将塔河流域42县市归为A、B、C、D 4种资源承载力匹配区,并总结其时序演变特点和发展策略。  相似文献   

14.
The mosquito Aedes aegypti is the primary vector of dengue and is common throughout tropical and subtropical regions. Its distribution is modulated by environmental factors, such as temperature. This study aimed to evaluate the influence of temperature on the life cycle and expansion of Ae. aegypti populations in the cities of Campina Grande, João Pessoa, and Patos. Samples of Ae. aegypti were collected in the three cities and raised in the laboratory. We assessed the life cycles of the three Ae. aegypti populations under six constant temperatures (16, 22, 28, 33, 36, and 39°C), selected on the basis of historical temperature tendencies of each city. We also used existing climate data to calculate projected temperature increases for all three areas. Our results suggest that Campina Grande, João Pessoa, and Patos will experience, respectively, maximum temperature increases of 0.030°C/year, 0.069°C/year, and 0.061°C/year, and minimum temperature increases of 0.019°C/year, ?0.047°C/year, and ?0.086°C/year. These projected increases will result in temperatures favorable to the Ae. aegypti life cycle, causing rapid population growth. Therefore, Ae. aegypti populations are likely to expand in the mesoregions represented by these cities.  相似文献   

15.
16.
陈佳锐  李佳洺  马仁锋  张文忠 《生态学报》2023,43(10):4039-4053
青藏高原是中国“三区四带”生态系统保护和修复重大工程的重要单元之一,兼顾其生态安全与区域合理开发是保障中国生态稳定的基础。阐释区域开发强度与生态安全的耦合机制,设计了两者关系的衡量体系,测算了2011—2020年青藏高原区域开发强度与生态安全耦合协调度与分型。研究结果表明:(1)研究期青藏高原区域开发强度不断增大,超过90%的市(州)增幅大于10%,以西宁、拉萨为“双核心”向外空间溢出速度加快,分别带动周边海西州和林芝等区域开发扩张;青藏高原各市(州)生态安全指数呈上升趋势,超过60%市(州)增幅大于10%,呈“中西部带状洼地、东部纵向组团”格局,且生态安全指数洼地向新疆南缘移动;(2)青藏高原各市(州)开发强度与生态安全耦合协调度2011—2020年间有不同程度提升,超过50%市(州)达到“轻度耦合”类,未有市(州)达到“优质耦合”类,但存在较多市(州)呈现开发强度或者生态安全滞后。(3)青藏高原区域开发强度与生态安全耦合协调的格局演进差异明显,逐步形成由西宁、巴音郭楞和拉萨-滇西地区(丽江、迪庆和怒江)三大组团逐渐向临近区域扩张,形成了“东高西低、多组团并列”格局。一定程度揭示了青...  相似文献   

17.
18.
基于BP神经网络的京津冀城市群可持续发展综合评价   总被引:2,自引:0,他引:2  
孙湛  马海涛 《生态学报》2018,38(12):4434-4444
在综合分析了京津冀城市群各城市功能定位的基础上,构建了包含经济发展、社会发展、科技创新和生态环境4个子系统的城市可持续发展评价指标体系,运用2006—2015年的数据,采用熵值法和BP神经网络对京津冀城市群可持续发展能力进行非线性测度与分类,结果较为理想。结果表明:(1)北京和天津处于高可持续发展水平,可持续发展能力在空间上呈现出以京、津为中心随距离递减的趋势,最南端的邯郸和邢台处于低可持续发展水平;(2)北京可持续发展能力呈现下滑趋势,其他城市可持续发展能力逐年稳步上升,大城市可持续发展压力较大;(3)城市在不同子系统中存在各自的优劣势。各个子系统在可持续发展中均起到重要作用,城市宜结合各自子系统的优、劣势制定具有针对性的发展对策。  相似文献   

19.
Cyanobacteria samples were collected from smears and mats growing on the surfaces of buildings, roadside walls, rocks, and monuments near Gimhae City, Korea. These populations were not as thick and dense, nor as diverse, as those found in temperate and tropical regions. Crusts at Gimhae City were dominated by colonial forms of species fromChroococcus, Aphanothece,Aphanocapsa, Gloeofthece,Gloeocapsa, andChroococidiopsis, as well as by filamentous forms from species ofScytonema andTolypothrix. The colonial forms appeared primarily as smears, especially for species ofGloeocapsa andChroococcidiopsis, whereas filamentous forms were the major constituents of mat populations. Invariably, the cells and trichomes of these colonial and filamentous forms were enclosed with a thick, firm, multi-colored laminar sheath, as seen by transmission electron microscopy. Such an association between cell walls and trichomes was stronger in the colonial forms, particularly forGloeocapsa, compared with the filamentous forms, in which the sheath did not detach from the wall even under arid conditions. The organization of cytoplasmic structures, particularly the thylakoid membranes, was least affected by acute dryness.  相似文献   

20.
Grazer-induced colony formation in the common green alga Scenedesmus acutus may be interpreted as an anti-grazer defense. Costs are to be expected because otherwise the protected colonial morph would be the norm. Analysis of growth rates, light harvesting in terms of photosystem II (PSII) efficiency using Xe-PAM fluorescence measurements and sedimentation rates were compared among unicellular and induced colonial populations. No differences in growth rates and PSII efficiency were detected between unicellular and colonial populations. However, colonial populations had higher settling velocities than unicellular populations. Hence, costs may be attributed to enhanced sinking out of the euphotic zone resulting in reduced growth due to lower light and temperature in deeper water layers.  相似文献   

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