基于扎根理论的杭州市梅家坞旅游城市化特征与机制

论文选取杭州市梅家坞村为案例地,通过5次实地调研和访谈获取研究资料,运用扎根理论构建了城市近郊地区旅游城市化特征和发生机制模型。研究表明：梅家坞村旅游城市化过程特征和发生机制可抽象成土地利用变化等11个范畴及31个概念;在旅游发展驱动下,多重要素实现了综合动态变化,在不改变乡村风貌、城乡和谐的条件下,推动了新型城市化进程。论文提出并分析了旅游城市化过程特征和发生机制理论模型,认为“梅家坞现象”是旅游城市化的积极例证,是管窥中国“田园城市”的发展方向与路径。     

城镇化背景下海岛资源环境承载力评估

在建设海洋强国的关键时期,海岛的生态保护和开发利用均至关重要。城镇化对海岛生态系统带来了深刻的影响,开展海岛资源环境承载力评估对管控人类开发行为、维护海岛生态平衡具有重要意义。论文以我国北方典型海岛—庙岛群岛为研究区,构建了一套综合开发强度和生态状况的海岛资源环境承载力评估方法并开展评估,结果显示：1）群岛尺度上,海岛资源环境承载力处于临界超载状态;2）单岛尺度上,南长山岛处于轻度超载状态,北长山岛、庙岛和大钦岛处于临界超载状态,小黑山岛、大黑山岛、砣矶岛、小钦岛、南隍城岛和北隍城岛处于可载状态,不同海岛应实施不同的保护与利用模式;3）区块尺度上,海岛资源环境承载力表现出了明显的空间分异性特征,可载区占41.7%,临界超载区占30.0%,轻度、中度和重度超载区分别占15.9%、8.1%和4.3%,超载区主要分布在各岛的城镇建设区域。     

乡村在城镇化过程中受到的冲击及其发展问题

中国是一个农业历史悠久的大国,乡村在社会中具有重要地位。通过近30多年的改革开放,乡村的建设和农业生产水平均有了显著的提高。但是在工业化、城镇化的浪潮下,乡村所受到的冲击十分剧烈。城镇化是经济与社会发展的强大动力,也是历史发展的必然趋势。城镇化进程有其客观规律,而且城市与乡村之间有着密切联系。因此,人为地阻挡城镇化不利于经济发展。然而,若不顾实际条件,不惜代价地加快城镇化进程,不仅难以保持和提高城市的经济发展和生活质量,而且对乡村的影响会更大。本文在论述中国1949年以来几个阶段城镇化特点的基础上,从近年来城乡差距与乡村人口劳动力的变化、土地高速非农化与粮食安全、乡村生态环境、乡村文化四个方面论述快速城镇化对乡村的冲击,并在此基础上讨论乡村的发展问题。根据上述乡村发展问题,本文提出若干意见,其中最要顾及的是新型城镇化进程中的乡村建设和农业生产。由于我国的自然条件、资源禀赋、各地的经济区位差异很大、发展的起点不同、进程有快慢、水平有高低,所以,以人为本的新型城镇化,特别要在城乡发展一体化的进程中,构建平等协调的城乡关系。各地城镇化的发展时序可有所不同,但必须因地制宜、同时做好乡村发展规划,力求农业现代化与工业化、信息化、城镇化同步,从而使农业和乡村经济得到持续发展。     

人口增长与自然资源

目前,世界人口政策所面临的突出问题是人口的增长与土地、淡水、动物、植物等自然资源和环境等方面的不平衡。人口的急剧增长加重了自然资源的压力,削弱了可再生资源的生产能力,在很大程度上使自然资源遭到严重的破坏。本文分析了人口增长与土地利用、森林资源、水资源、生物资源、能源和海洋资源的相互关系,指出确保人口增长与自然资源的产量和物种保护协调一致的唯一出路是严格控制人口数量增长。从另一个方面,反映了自然资源开发与保护的重要意义。     

Urban sprawl into Natura 2000 network over Europe

Urban growth is a major threat to biodiversity conservation at the global scale. Its impacts are expected to be especially detrimental when it sprawls into the landscape and reaches sites of high conservation value due to the species and ecosystems they host, such as protected areas. I analyzed the degree of urbanization (i.e., urban cover and growth rate) from 2006 to 2015 in protected sites in the Natura 2000 network, which, according to the Habitats and Birds Directives, harbor species and habitats of high conservation concern in Europe. I used data on the degree of land imperviousness from COPERNICUS to calculate and compare urban covers and growth rates inside and outside Natura 2000. I also analyzed the relationships of urban cover and growth rates with a set of characteristics of Natura sites. Urban cover inside Natura 2000 was 10 times lower than outside (0.4% vs. 4%) throughout the European Union. However, the rates of urban growth were slightly higher inside than outside Natura 2000 (4.8% vs. 3.9%), which indicates an incipient urban sprawl inside the network. In general, Natura sites affected most by urbanization were those surrounded by densely populated areas (i.e., urban clusters) that had a low number of species or habitats of conservation concern, albeit some member states had high urban cover or growth rate or both in protected sites with a large number of species or habitats of high conservation value. Small Natura sites had more urban cover than large sites, but urban growth rates were highest in large Natura sites. Natura 2000 is protected against urbanization to some extent, but there is room for improvement. Member states must enact stricter legal protection and control law enforcement to halt urban sprawl into protected areas under the greatest pressure from urban sprawl (i.e., close to urban clusters). Such actions are particularly needed in Natura sites with high urban cover and growth rates and areas where urbanization is affecting small Natura sites of high conservation value, which are especially vulnerable and concentrated in the Mediterranean region.     

北京市流动人口聚居区人居环境市民化类型分异

以流动人口聚居区为研究对象,构建流动人口聚居区人居环境市民化评价指标体系,评价北京市典型流动人口聚居区的人居环境市民化程度,分析流动人口聚居区人居环境市民化的类型分异特征,并在研究基础上提出不同空间类型流动人口聚居区人居环境市民化的提升路径。结果表明:流动人口聚居区人居环境市民化进程呈“由近及远”的圈层式空间推移过程,并高度依赖于土地城市化水平;流动人口聚居区人居环境市民化存在显著的类型分异。据此,提出近郊城中村型、近郊城市住宅型和远郊城中村型3类流动人口聚居区应分别采取重建提升模式、优化提升模式和存续提升模式,以高效、有针对性地提升流动人口聚居区人居环境,缩小流动人口与本地户籍人口的人居环境差距,实现流动人口市民化的发展目标。     

生态经济区城市化与生态环境整合动态评价--以雅安市为例

在对雅安市实例评价中,综合考虑了城市化质量、环境和生态3个子系统,最终选取了42个要素指标,建立了3级城市化与生态环境整合评价指标体系;将灰色关联度分析法用于整合动态评价,用层次分析法确定各级指标权重。在参考国家标准值和国内良好特色城市现状值的基础上,结合雅安实际,构造了各项对应指标的目标序列,将其作为该市2007年目标值,计算得到各子系统分指数和整合指数,对其变化趋势和关联性进行了评价分析,发现雅安市正处于强生态弱城市化的勉强协调发展阶段。     

飞机草提取物对小菜蛾产卵驱避活性的研究

以干扰作用控制指数作为评价指标,测定了飞机草提取物和乙醇提取物的不同萃取物对小菜蛾产卵驱避作用活性。结果表明,飞机草乙醇提取物及其氯仿萃取物对小菜蛾具有较强的驱避作用,驱避效果达80％以上,对小菜蛾起驱避作用的活性成分主要存在于氯仿萃取物中。     

Modelling strategies for the management of the critically endangered Carpentarian rock-rat (Zyzomys palatalis) of northern Australia

The Carpentarian rock-rat (Zyzomys palatalis) is a critically endangered endemic rodent known from only four sandstone gorges in the southeast Gulf of Carpentaria, Northern Territory, Australia. These gorges harbour thickets of monsoon rainforest and broadleaf woodland, surrounded by a Eucalypt savanna matrix. The long-term persistence of Z. palatalis is threatened by altered fire regimes, grazing by feral animals and stock, weed intrusion, and the stochastic hazards associated with small, fragmented populations. To assess the relative importance of these threats and develop practical management options, a population and habitat simulation model was developed, based on the best existing data. Population viability was predicted to be highly sensitive to the frequency of hot, late dry-season fires. Progressive habitat degradation (due predominantly to intense late dry-season fires) is likely to substantially reduce population size and lead to the probable extinction of the species within the next 100 years. The most effective management strategy to counteract this threat would be regular, controlled, fuel reduction burns in the vegetation around the gorge entrances during the early dry season. Establishing a new population (through translocation of captive-bred individuals) would not appreciably reduce extinction risk, but could provide valuable additional data on the impact of threats, if conducted as an adaptive management experiment.     

有害物品运输的总风险分析

随着工业的发展,有害物品的生产量和运输量均在逐年增加,有害物品对环境和人的危害正在扩大和加深。有害物品运输中的风险是有害物品对于人类、环境和财产等方面威胁的最为重要的组成部分。笔者将有害物品的运输风险分为人口风险、环境风险和财产风险3个部分;在基于事故发生率和事故产生的后果两个方面,分别对人口风险、环境风险和财产风险进行了度量,并给出了风险度量的模型。同时由于各个部分风险度量的量纲并不统一,笔者对3部分风险进行了度量的统一化,获得了总风险的构成,并与传统的单独考虑人口风险的情况进行了对比,为有害物品的运输提供了参考依据。