What is the Meaning of ‘Social Mix’? Shifting perspectives in planning and implementing public housing estate redevelopment     

Kathy Arthurson  Iris Levin  Anna Ziersch 《The Australian geographer》2015,46(4):491-505

This paper unravels a variety of perspectives about the concept of social mix, drawing on a case study of the implementation of a redevelopment project in Melbourne. The first part provides a theoretical overview of two internationally predominant academic debates around policy interpretations of this concept, namely social mix as a means for promotion of social inclusion; and as a state-led form of gentrification. These two arguments are usually presented as one, with social inclusion and reductions of concentrations of disadvantage one side of the ‘social mix policy’ coin, and state-led gentrification the other. This paper contributes to the national and international literature on public housing estate regeneration and social mix policies through exploring the question of whether these two ideas about social mix were shared by different stakeholders as the ‘messy’ process of redevelopment unfurled. Interviews were conducted with public tenants, homeowners and homebuyers, private renters and local service providers at the Carlton Housing Estate to explore the diverse perspectives of various stakeholder groups as estate design and implementation shifted. The study identified that as a result of the global financial crisis and the developers exerting pressure on government there was a gradual move away from perceiving social mix as a policy tool for encouraging social inclusion at Carlton, between public housing tenants and private residents, towards a different form of social mix and inclusion. Contrary to intentions, the revised form of social mix at Carlton was perceived as a means to harness market capital and attract higher income residents to the inner city.  相似文献   

四川喇叭河自然保护区珙桐群落特征与更新   总被引：4，自引：0，他引：4  

王海明  李贤伟  陈治谏  王海娥  徐云  高建武  杜占青 《山地学报》2005,23(3):360-366

在对四川喇叭河自然保护区珙桐群落进行生态学调查的基础上,着重分析了该区珙桐群落植物的物种构成、群落结构、重要值排序、simpson指数、Shannon-Wiener指数,以及珙桐群落的生境条件、更新动态等。研究结果表明：(1)喇叭河自然保护区珙桐群落是一种典型的中亚热带中山山地常绿、落叶阔叶混交林植被;适宜分布于温暖、潮湿、雨量充沛、云雾多、日照少、山陡沟深的地段;(2)珙桐群落植物种类丰富、古老、特有性强;(3)珙桐群落垂直结构明显,珙桐构成建群种;草本层发达;(4)该地区珙桐以有性和无性繁殖更新,但有性繁殖能力很低,以无性繁殖更新为主,群落在其分布区内是一种稳定存在的群落类型。  相似文献   

海洋多毛类动物的再生演化     

张琳琳  翁洁羊  李倩 《海洋与湖沼》2021,52(2):450-467

再生是生物体丢失的组织或器官重新生长和修复的过程,是生物科学的本质问题之一。再生现象在生物界中广为分布,但不同生物的再生能力却存在着巨大差异。虽然近年来再生的分子和细胞机制取得了显著的研究进展,但驱动物种再生能力多样性形成的遗传机制尚不明确。海洋多毛类因其多样且快速演化的再生能力和简单线性的分节结构成为研究再生演化的极佳类群。本文首先从生态和演化生物学的角度综合分析了多毛类再生的特点、进一步总结细胞和分子来源以及再生性状多样性,然后分析了印太交汇区的海洋多毛类再生性状的特点以及外在多圈层因素对再生性状的潜在驱动效应,并就未来的发展趋势提出了建议。  相似文献   

Revealing regional regeneration projects in three small towns in Aotearoa—New Zealand     

Harvey C. Perkins  Michael Mackay  Deborah Levy  Malcolm Campbell  Nick Taylor  Raewyn Hills  Karen Johnston 《New Zealand geographer》2019,75(3):140-151

We discuss case studies of three South Island small towns: Ashburton, Timaru and Oamaru and their wider local authority jurisdictions, focusing on how local stakeholders are defining the issues facing these places and identifying, prioritising and investing in regeneration initiatives, sometimes with the support of central government and other external agencies. Our key finding is that small‐town regeneration is complex, demands a long‐term local collaborative approach, and significant investment in skills, information sharing and programme development, some of which needs to be provided by external, central government, agencies.  相似文献   

基于文献计量方法的国内外城市更新比较研究   总被引：1，自引：1，他引：0  

孙威  王晓楠  盛科荣 《地理科学》2020,40(8):1300-1309

采用文献计量方法,利用Citespace工具对国内外城市更新研究进行知识图谱分析,从演化过程、发文期刊和研究机构的特征、研究热点等方面对比国内外城市更新研究的差异。研究表明：① 国内外城市更新研究的发文量呈现波动上升的趋势,在快速发展阶段尤为显著,每年发文量分别达到117篇和238篇;② 研究文献多集中在城市规划、区域研究、城市设计、建筑学等期刊。相对于国外,国内发文期刊更集中。国内排名前10的期刊发文量占比达46.65%,国外仅29.84%;③ 国内外的研究机构间初步形成合作网络,但网络联系与合作程度依然较低。相对于国外,国内研究机构间联系更紧密。④ 国外研究热点集中在伙伴关系与公众参与、绅士化、可持续发展、城市转型和文化创意等方面,国内研究热点体现在旧城改造与房地产开发、历史街区和工业遗产的保护与更新、广州?深圳城市更新的探索与实践、公众参与的初步探讨等方面。  相似文献   

二次生烃过程中升温速率对生烃途径的影响 --以鄂尔多斯烃源岩生烃动力学研究为例     

雷天柱  夏燕青  张瑞  靳明  邱军利 《矿物岩石》2006,26(2):97-99

采用生烃动力学方法对鄂尔多斯已熟烃源岩进行模拟实验,与以往结果有所不同,实验证明在源岩二次生烃过程中,慢速升温并不利于液态烃的生成,而快速升温才更有利于生成液态烃。这可能是因为在慢速升温条件下,有机质可以有足够长时间缩聚成超大基团,而快速升温则易造成中等分子链的断裂,从而导致快速升温时抽提物产率高于慢速升温。因此,升温速率的差异对有机质的演化影响不只是影响反应速率,更重要的是会改变反应路径,从而对于像鄂尔多斯这样存在二次生烃的盆地,应适当重视那些高地温梯度区块石油资源的寻找。  相似文献   

条斑紫菜离体组织再生苗的研究   总被引：1，自引：0，他引：1  

梅俊学  费修绠 《海洋科学》2000,24(6):39-43

条斑紫菜叶状体离体组织（切块）在一定培养条件下,其营养细胞经过一系列的变化可产生出幼茵。本研究发现切块越小出苗越早、单位面积离体组织出苗量越多。成熟叶状体上靠近雌雄性细胞的区域与其他部位的营养细胞相比形成幼苗较早,离这一区域越远的细胞成苗越晚。离体组织细胞成苗的适宜水温为１５￣１７℃。在２０￣２５℃下部分细胞进行不规则分裂形成深紫红色的细胞团。当降温至１７℃时,它们仍可转化为幼苗。  相似文献   

Interaction between water flow and oxygen deficiency on growth in the infaunal brittle star Amphiura filiformis (Echinodermata: Ophiuroidea)     

H. C. Nilsson 《Journal of Sea Research》2000,44(3-4)

Interactions between ‘oxygen concentration’ (normoxia: >80% oxygen saturation, and hypoxia: 18% oxygen saturation) and ‘water flow velocity’ (low: 0.1 cm s⁻¹, and moderate: 0.5 cm s⁻¹) were studied on growth rates in the brittle star Amphiura filiformis in a flow-through aquaria system. Effects of ‘sublethal predation’ on growth rates were investigated as ‘number of amputated arms’ (1 and 3 arms) and ‘amputation of the disk’. A significant interaction between oxygen concentration and water flow velocity was observed in mean arm regeneration rate, but in both flow velocities higher mean arm regeneration rates were observed in normoxia compared to hypoxia. In hypoxia a positive response in arm regeneration rate was observed in moderate flow compared to low flow velocity. In normoxia, however, no response to flow velocity was observed. The latter observation indicates that Amphiura filiformis is able to maintain the ventilation of the burrow at low flow velocities, but in low oxygen concentrations hydrodynamic forces seem to affect growth. A significant interaction between oxygen concentration and disk amputation was observed in both arm and disk regeneration rates, indicating that the disk is the major organ for gas exchange in this species. The number of arms amputated, however, did not affect mean arm regeneration rate. The results obtained in this study suggest that the secondary production in subtidal infaunal populations could be negatively affected by low oxygen concentrations and that this response is even more negative in combination with low flow velocities in the near-bottom water.  相似文献   

Mapping post-fire forest regeneration and vegetation recovery using a combination of very high spatial resolution and hyperspectral satellite imagery     

《International Journal of Applied Earth Observation and Geoinformation》2013

Careful evaluation of forest regeneration and vegetation recovery after a fire event provides vital information useful in land management. The use of remotely sensed data is considered to be especially suitable for monitoring ecosystem dynamics after fire. The aim of this work was to map post-fire forest regeneration and vegetation recovery on the Mediterranean island of Thasos by using a combination of very high spatial (VHS) resolution (QuickBird) and hyperspectral (EO-1 Hyperion) imagery and by employing object-based image analysis. More specifically, the work focused on (1) the separation and mapping of three major post-fire classes (forest regeneration, other vegetation recovery, unburned vegetation) existing within the fire perimeter, and (2) the differentiation and mapping of the two main forest regeneration classes, namely, Pinus brutia regeneration, and Pinus nigra regeneration. The data used in this study consisted of satellite images and field observations of homogeneous regenerated and revegetated areas. The methodology followed two main steps: a three-level image segmentation, and, a classification of the segmented images. The process resulted in the separation of classes related to the aforementioned objectives. The overall accuracy assessment revealed very promising results (approximately 83.7% overall accuracy, with a Kappa Index of Agreement of 0.79). The achieved accuracy was 8% higher when compared to the results reported in a previous work in which only the EO-1 Hyperion image was employed in order to map the same classes. Some classification confusions involving the classes of P. brutia regeneration and P. nigra regeneration were observed. This could be attributed to the absence of large and dense homogeneous areas of regenerated pine trees in the study area.  相似文献   

Close coupling between ammonium uptake by phytoplankton and excretion by Antarctic krill, Euphausia superba     

M.J. WhitehouseA. Atkinson  A.P. Rees 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(7):725-732

In this study we examined the hypothesis that, under conditions of replete macronutrients and iron in the Southern Ocean, phytoplankton abundance and specific N uptake rates are influenced strongly by the processes of grazing and NH₄ regeneration. NH₄ and NO₃ uptake rates by marine phytoplankton were measured to the northeast and northwest of the island of South Georgia during January-February 1998. Mean specific uptake rate for NO₃ (vNO₃) was 0.0026 h⁻¹ (range 0.0013-0.0065 h⁻¹) and for NH₄ (vNH₄) was 0.0097 h⁻¹ (0.0014-0.0376 h⁻¹). vNH₄ was related positively with NH₄ availability, which ranged from 0.1 to 1.5 mmol m⁻³ within the upper mixed layer. Ambient NH₄ concentrations and vNH₄ were both positively related to local krill biomass values, computed from mean values along acoustic transect segments within 2 km of the uptake measurement stations. These biomass values ranged from ∼1 g krill fresh mass m⁻² in the northwest to >4 kg krill wet mass m⁻² in the northeast. In contrast to the variability found with NH₄ concentrations and uptake rates, vNO₃ was more uniform across the sampling sites. Under these conditions, increasing NH₄ concentration appeared to represent an additional N resource. However, high vNH₄ tended to be found for stations with lower phytoplankton standing stocks, across a total range of 0.24-20 mg chlorophyll a m⁻³. These patterns suggest a coupling between phytoplankton biomass, vNH₄ and krill in this region of variable but high krill biomass. Locally high concentrations of krill in parts of the study area appeared to have two opposing effects. On the one hand they could graze down phytoplankton stocks, but on the other hand, their NH₄ excretion supported enhanced uptake rates by the remaining, ungrazed cells.  相似文献