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1.
In this paper, we study urban migrants' sense of place in Guangzhou, China, focusing on the structural relations between place attachment, identification and dependence as the three key place dimensions. Through both quantitative structural equation modelling and qualitative analysis of in‐depth interviews data, our research suggests that migrants' sense of place demonstrates complex relationships between the three registers of emotional attachment, identity formation and functional dependence. The construction of sense of place is also related to the personal experiences of living as urban ‘outsiders’. Our research also reveals a striking difference between the city and community levels in terms of the ways in which migrants' sense of place is constructed. Urban migrants tend to exploit the functional utilities of microscopic urban spaces to meet their demands for recreation, education and socialisation. On the other hand, their sense of place to the city is largely compromised by their attachment to the hometown and conditioned by their personal identification to the city.  相似文献   

2.
Using texts from online blogs, this study aimed to analyze the effect of perceived characteristics of a place in the virtual space and their influence on its economic performance. Specifically, this study analyzed old retail space (traditional markets) in Seoul by empirically examining the relationship among the perceived characteristics, economic performances, and the physical and operative conditions of the markets’ facilities. The perceived characteristics by the bloggers were analyzed by the text-mining of the blog posts. Next, the associations among the multiple factors including the perceived characteristics, economic measures, were analyzed by PLS-SEM. Three types of characteristics were found from the texts: (a) value shopping, (b) novelty & food, and (c) affective sentiments. Among them, novelty & food have significant positive effects on annual sales growth and the vacancy reduction rates of the markets. The improved physical condition also had a positive direct effect on annual sales growth, which can be partially explained by its positive mediating effects on Novelty & Food. The operating condition had no significant relationship with the perceived characteristics but had significant effects on the four economic measures. The results imply that renovation projects could diminish certain characteristics of the space (i.e., affective sentiments), but it enhanced other place characteristics (i.e., food and novelty) following economic gains.  相似文献   

3.
本文通过1988~1990年度的研究,明确了三类高产品种产量与其构成因素的关系,比较了三类品种的产量潜力和稳产性能,认为中间型品种具有较多的有利因素.在山东生态条件下,高产品种的产量结构,应在兼容大穗型、多穗型品种的前提下,着重走中间型的路子.  相似文献   

4.
We indirectly analyze the residential environment for long-staying internationals in Seoul, Korea, by extending the image–satisfaction–loyalty mechanism widely used in tourism, specifically by examining the internationals' satisfaction and loyalty. We consider residential difficulties, sociodemographics, and survey years along with image as exogenous variables and evaluate satisfaction not only in terms of its absolute but also its relative level, which is the difference between absolute satisfaction (AS) and previous expectation. Tourism studies have measured loyalty using individuals' intention to recommend to another and their own revisit intention, but we evaluate the revisit intention with place attachment/hometown perception, which is more suitable for long-staying residents. The variables are measured with 2016–2018 data from an annual quality of life survey for Seoul residents (n = 5279 individuals) and analyzed with structural equation modeling. Our results show that the conventionally used AS is associated only with recommendation intention, but the relative satisfaction (RS) both with recommendation intention and hometown perception. Regarding the exogenous variables, AS is substantially affected by image and RS is somewhat strongly influenced by residential difficulties. However, image is the principal determinant of loyalty level, whether recommendation intention or hometown perception. These findings confirm the applicability of the image–satisfaction–loyalty mechanism not only to short-staying inbound tourists but also to long-staying international residents.  相似文献   

5.
Deployment of diversity at the species and at the genetic levels can improve the ability of crops to withstand a wide range of biotic and abiotic stressors in organic and low-input cropping systems, where the response to stresses through external input is limited or restricted in comparison with conventional systems. Although there are several strategies to use agrobiodiversity in wheat-based systems, their implementation is limited by the lack of a clear relationship between agrobiodiversity and provision of key agroecosystem services. In a three-year field trial in Central Italy we compared common wheat Italian and Hungarian pure lines, Italian old cultivars and Hungarian and British Composite Cross Populations (CCPs), grown with or without a contemporarily sown Subterranean clover living mulch. We aimed at linking crop performance, in terms of yield, weed reduction and disease susceptibility, to three categories of functional diversity: (1) functional identity, represented by the identifying traits of cultivars, (2) functional diversity, represented by the genetic heterogeneity of wheat crop population, and (3) functional composition, represented by the co-presence of wheat and the living mulch.Concerning cultivars, effects of functional identity were predominant for weed reduction and grain yield. Old cultivars tended to better suppress weeds but to be less yielding. Italian cultivars were more advantaged than cultivars of foreign origin, thanks to a better matching of their growth cycle into local climate. Functional diversity effects on yield and weed reduction were confounded with identity effects, given that all the CCPs were of foreign origin. In fact, the performance of CCPs was generally aligned with a central-European pure line. However, differences in yield components suggest that CCPs can evolve peculiar yield formation strategies. Moreover, CCPs were less susceptible than pure lines to foliar diseases. For functional composition, the living mulch was able to reduce dicotyledonous weed abundance and weed biomass without reducing wheat yield unless wheat was poorly established. Despite the strong morphological and phenological differences among the tested cultivars, no interactions were found between cultivar and living mulch presence, suggesting that, in conditions similar to our experiments, there is room to freely combine elements of crop diversity. Crop diversification strategies in wheat should be further explored and optimized, especially by constituting CCPs from locally adapted germplasms and by improving the feasibility and efficacy of legume living mulches.  相似文献   

6.
Two series of field trials were performed at three sites in Schleswig-Holstein between 1981 and 1988 to inquire into the yield structure of European winter types of Vicia faba L. and to compare their yield potential with that of spring types. Due to low winter survival, 6 winter types could be evaluated only in 4 environments in dependence of 1–3 sowing times (series α: seed rate 30/m2) and 1 winter type in 5 environments in dependence of 3 sowing times and 3 seed rates (series β: seed rate 15, 30, 45/m2). Seed yield of winter type averaged 410 g/m2 (D.M.) surpassing spring types by about 14 %. Environments caused a considerable variation in yield (275–620 g/m2) and in each yield component of winter types, while sowing dates and seed rates hardly affected the components seeds/pod and seed weight, which displayed stable genotypic rank orders. Compensative forces among the components plants/m2, tillers/plant and pods/tiller, were established. Plant densities of less than 10/m2 in spring, generally led to seed yield below 350 g/m2. Variation between 15–30 plants/m2 due to environments, sowing times or seed rates were frequently not fully compensated by tillering of plants, but often variation of the thus formed yield potential was reduced by pod set of tillers resulting in 210–270 pods/m2. The direction of correlations of pods/tillers with tillers/plant and plants/m2 differed due to experimental conditions whereas negative correlations between pods/tiller and tillers/ m2 were generally evident. Tillering was significantly influenced by the sowing time, though the increase because of early sowing was often covered by compensative effects of different plant densities. A genotypic capability to produce reproductive tillers was demonstrated using an approach which considered different plant densities and compensative forces. Neither a genotypic capability of tillers to set pods nor direct effects of environments or sowing time on pod set were established.  相似文献   

7.
Abstract: The transformation of urban landscapes is as much a physical process as it is a symbolic one. Material changes in the form of demolition and redevelopment are often accompanied by changes in the image and identity of places, as well as the personal and collective memories associated with these places. Focusing on the Singapore River, we explore how waterfront redevelopment has rendered certain activities, people and place memories invisible, to be replaced by other landscape elements and their associative identities. Through ‘creative destruction’ and ‘destructive creation,’ the waterfront's transformation is evident in three areas: its built environment (‘builtscapes’), activities and events (‘eventscapes’) and displays of public art (‘artscapes’). We contend that landscapes reflect the tensions between ‘remembering to forget’ and ‘forgetting to remember’ in ‘New Asia‐Singapore,’ a city attempting to blend modern Asian dynamism with tradition and heritage.  相似文献   

8.
为明确成都平原水稻直播技术的适宜品种和配套高产栽培技术,以杂交籼稻‘德香4103’和常规籼稻‘金农丝苗’为材料开展了田间试验,调查测定了直播、机插秧及人工移栽等3 种栽培方式的生育期、分蘖成穗、叶面积消长、干物质积累、产量及其构成因素。结果表明,栽培方式间产量的差异与品种有关,杂交籼稻品种直播产量与人工移栽产量相当,高于机插秧;常规籼稻直播产量最高,机插其次,人工移栽最低。此外,直播稻群体数量增长最快,成穗以主茎和一次低位分蘖为主,抽穗后光合生产能力品种间存在显著差异。直播稻群体规模大,采用常规籼稻直播更有利于协调群体和个体的关系,依靠穗数优势实现高产。  相似文献   

9.
Abstract This paper examines the relationship between quality of life, rural development, and several socioeconomic variables. The analysis utilizes data obtained from a survey questionnaire administered to a random sample of more than 2,000 residents in West Virginia, and spatial data obtained by geocoding the survey respondents’ addressees. Quality of life is measured by a three‐point categorical measure of overall satisfaction, and development is measured by a goods and services availability index. A simultaneous ordered probit model is used to examine the relationships. The empirical results are consistent with the theoretical predictions and indicate a simultaneous relationship between quality of life satisfaction and rural development.  相似文献   

10.
The authors investigate counter-urbanization and population change in Georgia between 1960 and 1980 by examining commuting patterns. "The immediate objective is to construct the entire set of commuting fields of both large metropolitan areas to metropolitan and nonmetropolitan employment centers. We then proceed to the relationship between commuting from nonmetropolitan areas to all levels of Georgia's urban hierarchy and population change in these nonmetropolitan settings. By matching population growth and decline areas with explicit employment ties...the nature of the population changes is much better understood." Data from the 1960, 1970, and 1980 censuses for 581 Census County Divisions (CCDs) in Georgia are analyzed. It is concluded that "most nonmetropolitan growth taking place in Georgia is associated with intensification of metropolitan commuting fields along with growth of nonmetropolitan centers and their influence along the very periphery of metropolitan spheres of employment influence. However, a significant share of Georgia's nonmetropolitan population revitalization is explained by growth independent of direct metropolitan influence. It would appear then that nonmetropolitan growth centers are an important part of the basis for population decentralization in Georgia. Metropolitan spill-over alone cannot account for counterurbanization on this portion of the American economic landscape."  相似文献   

11.
Cyclone Pam (March 2015) was an unprecedented event in Vanuatu forcing the simultaneous involvement of national and long‐term international actors, well integrated into the national disaster governance system, as well as numerous short‐term international actors, unfamiliar with the geopolitical and cultural disaster context of the country. Cooperation between these three groups of actors evolved through the three scales of bonding, bridging and linking social networking. This paper questions the different drivers and challenges within and across these scales of social networks affecting cooperation among the three different groups of actors during an emergency. Using a mixed methodology based on social network analysis, this paper utilises the case study of Cyclone Pam in Vanuatu to study the strengths and weaknesses of the disaster governance system in place based on bonding and bridging social capital to conduct disaster risk management and to prepare the integration of linking social capital when external support is needed. This paper contributes to the identification of key considerations in the development of resilience‐building strategies: the interactions of diverse actors to address disaster management needs and the reciprocal impacts of these interactions within and across the three different scales of social networks.  相似文献   

12.
陆地棉棉铃组分性状的基因型差异及与产量的关系   总被引:1,自引:1,他引:0  
为了探明陆地棉不同产量潜力品种棉铃性状的特点,于2008—2009年比较了3个大铃基因型与3个小铃基因型棉铃组分性状的差异。结果表明,大铃基因型的单铃纤维重、单铃种子重及单铃种子数显著高于小铃基因型,单粒种子重和单粒种子纤维重差异不显著。简单相关分析表明,单铃种子数与公顷皮棉产量呈极显著正相关(0.660**),但偏相关系数或直接通径系数较小或为负值(0.179,-0.052);而单株种子数与公顷皮棉产量的简单相关系数、偏相关系数和直接通径系数均为显著或极显著的正值(0.771*,0.650**,0.917**)。因此,单株种子数可作为皮棉产量选择的可靠指标。单粒种子纤维重和铃壳率受基因型效应的显著影响,受年份效应和年份×基因型互作效应的影响均不显著。说明单粒种子纤维重和铃壳率主要受遗传因素的影响,受环境因素的影响较小。  相似文献   

13.
Upland cotton (Gossypium hirsutum L.) hybrids display commercially useful levels of heterosis for lint yield. Cotton lint yield is primarily a multiplicative product of boll number and lint per boll, both of which can be further dissected into sub-components. Relationships among the yield components are complex where they further interact with the environment. To identify different yield components of hybrid cotton lint yield and their relationship with environment, three cotton varieties, DP51, STV474 and LA887 and, their respective hybrids were evaluated for lint yield components across five environments. Heterosis was observed for lint yield as well as yield components. The relationship between heterosis and mean environmental yield was negative for two hybrid combinations, whereas one hybrid showed increased heterosis from low to high yielding environments. Boll number was the major yield component contributing to lint yield. However, yield components contributing to the change in heterosis from low to high yielding environments were different for the three hybrids. The change in lint yield heterosis across environments was correlated with lint per boll and lint per seed for DP51 × STV474 and LA887 × DP51. Whereas, bolls number and boll retention were the main yield components contributing to higher lint yield heterosis of STV474 × LA887 in low yielding environments. Results also reveal effects of parental entries on lint yield as well as relationship of heterosis and environment.  相似文献   

14.
杨丽华  董冰 《中国农学通报》2012,28(29):310-316
理论界有关游客满意及其前置因素的研究已日趋成熟,但有关游客满意与购后行为关系的研究很少,尚未形成成熟的购后行为测量量表。本文在文献梳理的基础上,构建了休闲旅游服务情境下“顾客满意-购后行为”关系的理论模型。模型中满意度属性的界定以服务绩效和公平理论为依据,将“顾客满意”分为“满意”与“不满意”两个构面,对应于“积极行为”与“消极行为”两个购后行为构面。在模型构建的基础上提出了研究假设,并设计了调查问卷。本研究运用SPSS17.0软件对收集的174份有效问卷进行了信度与效度分析,并对假设中各变量之间的相关性进行了验证。研究结果表明,顾客满意与积极的购后行为正相关,与消极的购后行为负相关。同时,购后行为也对顾客满意产生影响,积极的购后行为正向地影响顾客满意,而消极的购后行为负向地影响顾客满意。本研究结果验证了服务公平与感知绩效理论在休闲旅游中的适应性,提出了顾客关系管理与服务补救策略在休闲旅游经营中的重要性。  相似文献   

15.
Many studies in economics and regional science claim a positive link between interpersonal trust and innovation by demonstrating a positive effect of trust on patenting. This contrasts many findings from organization level studies on trust and innovation, who report a variety of findings including inverted-U type relations. A possible explanation is that trust exhibits different roles in invention and innovation, as the former relies on knowledge commons while the latter directly embeds commercialization and the market context. This study attempts to reconcile the two set of findings by studying indicators of invention and innovation in relation to trust at the same unit of observation, by using the regional variation in Europe. I study the relationship between interpersonal trust and patent applications (a measure of invention), trademark applications (a composite indicator) and the share of innovative sales in turnover by SMEs (a direct indicator of commercialization), across European regions. I show that trust positively affects trademark applications with an effect that is comparable to that on patent applications. However, trust exhibits an inverted-U type relationship with innovative sales. Results collectively point to a strong role of trust in all three creative activities, including a negative effect at the higher end when the indicator is directly contingent on commercialization and sales. I also estimate the extent of spatial spillovers in the effect of trust on all three creative outcomes.  相似文献   

16.
对加拿大披碱草、老芒麦、杂种F1、C_0Ⅰ、C_1Ⅰ、C_0Ⅱ和C_1Ⅱ7种材料进行了同工酶和RAPD的分析,旨在通过分子标记方法探讨供试材料的亲缘关系.结果表明:在不同的生育期,EST同工酶酶谱具有较高的多态性,酶谱差异较大,在分蘖期杂种的EST酶谱偏向母本加拿大披碱草,根据该生育时期的酶谱特征可以鉴定杂种后代的的真实性,其他生育时期,EST酶带偏向父本老芒麦,而且没有明显的差异.SOD酶谱的差异只是体现在表达量的多少上,并没有出现特异性的条带.RAPD分析表明,加拿大披碱草与老芒麦的遗传一致度为0.72,遗传距离为0.328 5,在7种材料中亲缘关系最远;杂种后代与母本加拿大披碱草的遗传距离较近,而与父本老芒麦的亲缘关系相对较远;因此用RAPD分析材料的遗传关系更为合适.  相似文献   

17.
Summary In three experiments differential interactions between lettuce genotypes and Bremia lactucae races were investigated and also the influence of latent period, infection frequency and number of infected leaves on the level of resistance.In experiment 1 very significant differential interactions were observed mainly caused by two plant genotypes (PIVT 82 and PIVT 315) and race NL 7. In experiments 2 and 3 differential interactions were absent or of minor importance. Results suggest that partial resistance often was of a race-non-specific character. Latent period appeared to be a major component of resistance in the lettuce-Bremia lactucae relationship. It determines the onset of the next cycle of spore production and is also indicative of fungus growth in host tissue. Compared with infection frequency and number of infected leaves, latent period shows a small error variation and can efficiently be measured. The closeness of the relationship of the number of primary infections and the number of infected leaves with resistance level varied, depending on the experiment. The above three components appeared to be associated but the degree of the association varied. The variable behaviour of the three components suggests that they are governed by different genes.For the level as well as for the complexity and durability of the resistance, accumulation of as many components of resistance as possible is desirable. Therefore, in parents all such components should be analysed before crosses are carried out to improve resistance level. In the final products of crossing and selection the relative importance of components should also be investigated to determine whether an increased resistance level results from additional effects of the parents on one component (e.g. latent period) or from accumulation of different components in a plant genotype.Students at the Agricultural University Wageningen  相似文献   

18.
Te Iwi Maori     
The decade started with the 150‐year commemoration of the signing of the Treaty of Waitangi that established British governance. This was when Maori were severely and disproportionately affected by the structural adjustment programmes which had reduced their standards of living and thrown them back on their own community resources as government withdrew from community involvement. The continuing conflict between the desire to retain their collective Maori identity and the almost overwhelming forces of assimilation (internally) and globalisation affected fortunes of Maori New Zealanders (internationally). This is best exemplified by the conflict in the Treaty of Waitangi between British sovereignty and Maori tino rangatiratanga. As the decade progressed, government sought a full and final settlement of the many hundreds of historical treaty claims, with a unilateral declaration of what was available ($1 billion). Unilateral actions on either side did little to assuage the long‐standing sense of mutual mistrust between Maori and Pakeha which was fuelled by a hostile mass media. Notwithstanding, ‘progress’ was made, and the twentieth century ended with Maori and Pakeha closer together than they had ever been.  相似文献   

19.
STIRPAT (stochastic impact by regression on population, affluence, and technology) model is used to identify the influencing factors of agricultural carbon emissions in Jiangsu province. By referring to Kaya identity and combining with the actual situation of agricultural carbon emissions, four basic influencing factors were obtained: agricultural production efficiency, agricultural structure, agricultural economic development level, and agricultural population size. In addition, urbanization, mechanization, and natural disaster level were listed as influencing factors. The results demonstrated: (a) Urbanization was the first promoting factor of agricultural carbon emissions, indicating a 0.2510% increase in agricultural carbon emissions due to a 1% increase in urbanization. The other three positive factors were, respectively, agricultural mechanization, agricultural structure, and agricultural economic development and their influence indexes were 0.1481, 0.1163, and 0.0845, respectively. (b) Agricultural production efficiency was the most important factor to restrain agricultural carbon emissions. For every 1% increase in agricultural production efficiency, corresponding agricultural carbon emissions would be reduced by 0.3288%. Agricultural population size was also an important factor to reduce agricultural carbon emissions and its influence index was −0.045. Finally, we propose policy recommendations including implementation of orderly urbanization, dependence and development of low carbon technology, establishment of agricultural carbon compensation mechanism, etc.  相似文献   

20.
海南普通野生稻琼海居群与三亚居群的遗传分化   总被引:5,自引:0,他引:5  
普通野生稻(OryzarufipogonGriff.)是栽培稻的近缘祖先,蕴藏着丰富的优异基因,是宝贵的水稻遗传资源。普通野生稻主要分布在我国的南方地区,海南岛是我国普通野生稻的主要分布区之一,野生稻的遗传多样性曾经非常丰富。三亚是海南岛典型的热带地区,是普通野生稻主要的分布区。最近在海南琼海发现一个原生境普通野生稻居群,尚不清楚海南普通野生稻琼海居群与三亚居群之间的遗传关系。本研究采用37个SSR标记从SSR座位的多态率、SSR座位的基因杂合性、两居群间的遗传相似性和遗传距离以及两居群间的遗传分化等四方面,对海南普通野生稻琼海居群与三亚居群进行了遗传分析,旨在为海南普通野生稻的深入研究提供基础。结果表明SSR座位在两群体中存在较高的遗传变异,且其在普通野生稻三亚居群的遗传变异高于在普通野生稻琼海居群的遗传变异。SSR座位在琼海居群中的多态率为81.0811%,在三亚居群中的多态率为91.8919%;观察杂合性、理论杂合性、非偏性杂合性在三亚居群中的平均值为0.5651、0.4449、0.4661,高于在琼海居群中的相应平均值(0.4097、0.2057、0.2670)。根据Nei遗传相似性和遗传距离普通野生稻琼海居群与三亚居群间的遗传相似性为0.6385,遗传距离为0.4486。FST检验表明,两群体之间存在着中等程度的遗传分化(FST=0.3909),表明这两个普通野生稻居群内存在着60.91%的遗传变异。  相似文献   

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