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61.
[目的]甘肃省农业气候资源丰富,适宜种植的杂粮作物品种较多,但其杂粮种业发展存在诸多与现代农业不相适应的问题,严重制约了杂粮产业的发展,因此急需提出针对甘肃省特色杂粮种业发展的策略。[方法]文章通过实地调研与文献分析,全面系统地分析了杂粮种业的特点和存在问题,并提出了甘肃省特色杂粮种业的发展策略。[结果]调研发现,甘肃省杂粮种子产值高达2亿元以上,其种子研发体系正在完善,商业化速度逐步加快,市场前景广阔。但仍存在杂粮种业缺乏长远规划,杂粮作物种子市场尚不健全,缺乏育繁推一体化的种子企业,种子信息网络及监管机制不健全;育种创新能力有待提高,品种布局不尽合理;杂粮作物品种保护意识不强,对知识产权重视程度不够等诸多问题。因此需要充分发挥甘肃省自然气候生态特点,挖掘优势特色杂粮作物,整合资源,构建杂粮作物育种创新技术体系;建立健全杂粮种子质量监控体制机制;培育现代杂粮种业龙头企业和现代化销售网络等发展策略。[结论]甘肃杂粮作物种业具有广阔的发展空间。 相似文献
62.
城市自生群落具有重要的生态服务功能与潜力,但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合,探索一种介入栽培植物对城市自生群落进行改良,最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据,向已经演替1年的城市自生群落中引入63种栽培植物,按照分层的方式对群落进行改良。3年的观测结果表明,有61.9%的栽培植物可以在城市自生群落中定居并建立优势,能对76.7%的自生植物起到抑制作用,使55.8%的自生植物消失。相比城市自生群落,改良后的群落美观度提高29.4%,公众接受度提高24%,群落的物种丰富度提高至2.29倍。相比一般的人工植物群落,改良后的群落可以节约58.2%的建植成本,降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径,能有效提高群落的物种丰富度和美学价值,同时让自然参与群落设计过程,实现人与自然的合作。 相似文献
63.
64.
65.
通过对上海近30年的气候因子汇总分析,结合对上
海世博公园主要绿化树种生长状况调查和年度生物量计算,通
过典型相关性分析发现,极端高低温、强风和暴雨等5个气候
因子对树木的生长产生了不同程度的影响,有些因子严重阻碍
了树木的正常生长,成为障碍因子。经过10年的绿化实践验
证,上海世博公园对骨干树种的选择,以乡土树种为主,群落
结构较为稳定,且气候障碍因子对乡土树种的影响较小。在引
种外来树种时,采用气候相似植物区系法,结合植物耐寒、耐
热带图,把种源地划分为2个气候带和3个植物区系,并确定了
最南引种线,成功引种了红花槭等20种观花色叶乔木树种。 相似文献
66.
Creative hotspots have become a key driver for urban policies to stimulate social, cultural, environmental and organisational growth of creative and knowledge-based clusters, districts and hubs. However, their functional and spatial characteristics vary due to their different evolving structure as new spaces of economic activity in different contexts. This article points to a consideration of new foci for both land use and urban economic policy through a mapping of formal and informal creative hotspots in Brisbane, Australia. The study found two distinctive development patterns: (a) earlier top-down approaches as instigated by national and international innovation policies, and; (b) recently emerging bottom-up spaces for creativity, knowledge and innovation practices. This study examines how formal creative strategies and emerging informal creative spaces shape cities and urban policies. The methodology comprises online data collection and a review of creative and knowledge strategies and implementation policies. Data was then analysed via multiple mapping techniques illustrating the spatial distribution of creative hotspots, formal and informal formations, scale and land use characteristics. The research findings consolidate our understanding of Brisbane’s creative ecosystem and suggest new urban policy mechanisms to better foster the interrelationship between top-down and bottom-up approaches in cities, that is, between formally planned and large-scale interventions and small-scale organic and informal creative activities. 相似文献
67.
Tanya Jakimow 《International journal of urban and regional research》2020,44(3):429-446
Municipal Councillors (MCs) are the ‘familiar face of the state’ in Dehradun, India: the first port of call for citizens seeking to claim entitlements from the state. The way MCs respond to the requests of their constituents is a major factor in the uneven distribution of government welfare and services. This article seeks to contribute to understandings of citizen entitlements by drawing attention to the role of affect and emotion in shaping the interactions between MCs and voters. I examine the ways citizens consciously or unconsciously engender emotions and affective responses, and the effect these have in mobilizing MCs. Attention to the, at times, involuntary nature of these responses suggests a need to go beyond the instrumental and calculating motivations of municipal councillors, to consider the way they are compelled and animated to meet the demands of some citizens, but not of others. The capacity to affect, and the ways one is affected, are tied to the social identities and self-making projects of both the MC and the voter, resulting in an uneven (mal)distribution of state resources. A focus on affective configurations in urban governance thereby reveals heretofore overlooked determinants of unequal access to urban resources and services. 相似文献
68.
Jennifer L. Rice Daniel Aldana Cohen Joshua Long Jason R. Jurjevich 《International journal of urban and regional research》2020,44(1):145-165
As local governments and corporations promote ‘climate friendliness’, and a low-carbon lifestyle becomes increasingly desirable, more middle- and upper-income urban residents are choosing to live near public transit, on bike- and pedestrian-friendly streets, and in higher-density mixed-use areas. This rejection of classical forms of suburbanization has, in part, increased property values in neighborhoods offering these amenities, displacing lower-income, often non-white, residents. Increased prevalence of creative and technology workers appears to accelerate this trend. We argue that a significant and understudied socio-environmental contradiction also occurs where the actual environmental outcomes of neighborhood transformation may not be what we expect. New research on greenhouse gas emissions shows that more affluent residents have much larger carbon footprints because of their consumption, even when reductions in transportation or building energy emissions are included. We describe an area in Seattle, Washington, the location of Amazon's headquarters, experiencing this contradiction and show a distinct convergence of city investments in low-carbon infrastructure, significant rises in housing prices and decreases in lower-income and non-white residents. We conclude with a discussion of a range of issues that require more attention by scholars interested in housing justice and/or urban sustainability. 相似文献
69.
70.
Sara Safransky 《International journal of urban and regional research》2020,44(2):200-218
City governments are embracing data-driven and algorithmic planning to tackle urban problems. Data-driven analytics have an unprecedented capacity to call urban futures into being. At the same time, they can depoliticize planning decisions. I argue that this shift calls urban studies scholars to investigate geographies of algorithmic violence—a repetitive and standardized form of violence that contributes to the racialization of space and spatialization of poverty. This article examines this broader phenomenon through the case of a proprietary market value assessment that is being used to guide development in cities across the United States. The assessment employs an algorithm that helps city officials make critical decisions about which neighborhoods to target for investment, disinvestment and public service upgrades or disconnections. I argue that the racial, infrastructural, and epistemological violence associated with this evaluation can potentially lead to a new kind of municipal redlining. The article brings insights from critical race theory into conversation with critical scholarship on algorithms by analyzing how algorithmic violence works through data-driven planning technologies to depoliticize and leverage power while further entrenching racism and inequality. 相似文献