城市生态用地需求测算研究进展与展望

作为城市地域自然生态系统服务供给的基本载体,生态用地基于土地利用/土地覆被的内在关联将人类社会发展与自然生态演替耦合关联在一起,已成为统筹解决城市建设扩展与自然生态保护矛盾的重要综合途径;城市生态用地的需求测算直接决定供需均衡分析结果,是城乡统筹生态用地规划与管理的关键环节。本文在系统梳理生态用地概念内涵的基础上,对比分析了生态需求与生态用地需求的概念异同;提出基于空间与功能的城市生态用地需求测算概念框架,并据此将已有测算方法归并为经验判定法、生态系统服务法、空间格局法3大类,从综合性、代表性、阈值与规模、位置等方面对比分析了法定定额法、历史趋势预判法、生态足迹法、碳氧平衡法、生态安全格局法等具体方法的基本特征及其优缺点;最后将下一步研究的重点趋向概括为基于土地生态功能的城市生态用地分类、基于土地生态格局的城市生态用地效益综合测算、基于多目标情景的城市生态用地功能综合权衡、基于生态用地供需平衡分析的城市生态腹地识别4个方面。     

The political ecology of ecosystem services

The dominance of “ecosystem services” as a guiding concept for environmental management – where it appears as a neutral, obvious, taken-for-granted concept – hides the fact that there are choices implicit in its framing and in its application. In other words, it is a highly political concept, and its utility depends on the arena in which it is used and what it is used for. Following a political ecology framework, and based on a literature review, bibliometric analyses, and brief examples from two tropical rainforest countries, this review investigates four moments in the construction and application of the ecosystem services idea: socio-historical (the emergence of the discourse), ontological (what knowledge does the concept allow?), scientific (difficulties in its practical application), and political (who wins, who loses?). We show how the concept is a boundary object with widespread appeal, trace the discursive and institutional context within which it gained traction, and argue that choices of scale, definition, and method in measuring ecosystem services frustrate its straightforward application. As a result, it is used in diverse ways by different interests to justify different kinds of interventions that at times might be totally opposed. In Madagascar, the ecosystem services idea is mainly used to justify forest conservation in ways open to critique for its neoliberalization of nature or disempowerment of communities. In contrast, in the Brazilian Amazon, the discourse of ecosystem services has served the agendas of traditional populations and family farm lobbies. Ecosystem services, as an idea and tool, are mobilized by diverse actors in real-life situations that lead to complex, regionally particular and fundamentally political outcomes.     

天山中段地区重复地震时空特征研究

基于2009—2017年新疆区域数字地震台网记录的地震波形数据,利用波形互相关技术及主事件定位方法识别并重新定位了新疆天山中段及其周缘的重复地震。以波形互相关系数0.9作为阈值来确定研究区的重复地震事件,统计结果显示3万零181个事件中的1万1 618个为重复地震事件,这些重复地震事件组成了2395组重复地震对和重复地震丛,占总事件数的38.5%。根据重复地震重定位前后地震对之间距离的统计结果推测,该区域的系统定位误差约为5—10 km。进一步结合该区域最新的震源分类结果对不同震源类型重复地震的时空分布特征予以分析,结果显示:重复矿山爆破事件在空间上呈丛集性分布,且其中的93.6%发生于白天,同时呈现季节性发生模式,即爆破多发生于夏季,而冬季较少;而重复构造地震在空间上大多沿断层分布,24小时内呈随机分布的特征,且研究时段内每个月的活动水平相对平稳;重复诱发地震成丛分布于靠近油气田和水库的区域,但其中部分诱发地震的位置与构造地震重叠,发震时间特征与构造地震相似,为随机分布。      

Scientists' warning on extreme wildfire risks to water supply

2020 is the year of wildfire records. California experienced its three largest fires early in its fire season. The Pantanal, the largest wetland on the planet, burned over 20% of its surface. More than 18 million hectares of forest and bushland burned during the 2019–2020 fire season in Australia, killing 33 people, destroying nearly 2500 homes, and endangering many endemic species. The direct cost of damages is being counted in dozens of billion dollars, but the indirect costs on water-related ecosystem services and benefits could be equally expensive, with impacts lasting for decades. In Australia, the extreme precipitation (“200 mm day −1 in several location”) that interrupted the catastrophic wildfire season triggered a series of watershed effects from headwaters to areas downstream. The increased runoff and erosion from burned areas disrupted water supplies in several locations. These post-fire watershed hazards via source water contamination, flash floods, and mudslides can represent substantial, systemic long-term risks to drinking water production, aquatic life, and socio-economic activity. Scenarios similar to the recent event in Australia are now predicted to unfold in the Western USA. This is a new reality that societies will have to live with as uncharted fire activity, water crises, and widespread human footprint collide all-around of the world. Therefore, we advocate for a more proactive approach to wildfire-watershed risk governance in an effort to advance and protect water security. We also argue that there is no easy solution to reducing this risk and that investments in both green (i.e., natural) and grey (i.e., built) infrastructure will be necessary. Further, we propose strategies to combine modern data analytics with existing tools for use by water and land managers worldwide to leverage several decades worth of data and knowledge on post-fire hydrology.     

基于卓越测绘工程师培养的“双师型”教学团队的打造

"双师型"教学团队的打造是培养卓越测绘工程师的重要保障。介绍了"卓越工程师教育培养计划"的概念,详细分析了"双师型"教师及其教学团队的内涵,从调整政策,重构教师的考核和激励机制;加强教育,引导教师到企业进行专业实践;拓宽渠道,扩大兼职教师比例;产学研结合,丰富教师的实践经验等四个方面,论述了"双师型"教学团队的建设途径。     

A domain-independent methodology to analyze IoT data streams in real-time. A proof of concept implementation for anomaly detection from environmental data

ABSTRACT

Pushed by the Internet of Things (IoT) paradigm modern sensor networks monitor a wide range of phenomena, in areas such as environmental monitoring, health care, industrial processes, and smart cities. These networks provide a continuous pulse of the almost infinite activities that are happening in the physical space and are thus, key enablers for a Digital Earth Nervous System. Nevertheless, the rapid processing of these sensor data streams still continues to challenge traditional data-handling solutions and new approaches are being requested. We propose a generic answer to this challenge, which has the potential to support any form of distributed real-time analysis. This neutral methodology follows a brokering approach to work with different kinds of data sources and uses web-based standards to achieve interoperability. As a proof of concept, we implemented the methodology to detect anomalies in real-time and applied it to the area of environmental monitoring. The developed system is capable of detecting anomalies, generating notifications, and displaying the recent situation to the user.     

Free rocking response of a regular stone masonry wall with equivalent block approach: experimental and analytical evaluation

The evaluation of the dynamic behaviour of rocking elements is directly correlated to the energy dissipated because of the impacts at the base interface, which can be represented by means of a coefficient of restitution. This schematization is commonly accepted as representative of the out‐of‐plane response of stone masonry walls. An experimental campaign (in a lab environment) aiming at assessing the value of this coefficient for a sacco granite masonry wall is presented in this work. The rocking motion at a predefined bed joint level was induced in the tested specimens in order to validate a novel test setup designed to assess the coefficient of restitution value by means of a realistic reproduction of the rocking behaviour of a single element, under the hypothesis of an infinitely stiff system above the bed joint level. As the main objective of the work was to assess the rocking behaviour of a masonry wall that looses energy at the impacts at a certain joint level, the flexural behaviour was not desirable and had to be avoided. For this purpose, a test setup based on the equivalent block approach was developed. In the final section of this work, comparisons between experimental and numerical results are presented together with some preliminary conclusions on the appropriate modelling strategy and the values of the coefficient of restitution to be used for the seismic assessment of the out‐of‐plane rocking behaviour of this type of sacco stone masonry walls. Copyright © 2013 John Wiley & Sons, Ltd.     

订正与集成多模式的中国季度降水预测

针对两个最新换代的季度集合预测系统对中国季度降水预测中存在的系统缺陷,应用改进的贝叶斯联合概率模型（BJP）加以订正。对订正后的单一模式概率预测应用一种混合模型贝叶斯模型平均（BMA）方法加以集成,以综合各模式的优势来提高中国季度降水预测技巧。结果表明:BJP模型可有效地消除集合模式预测的系统偏差,同时大幅提高了概率预测的可靠性。经过订正的欧洲中尺度天气预报中心的 System4预测在许多季度在中国的很大区域范围内都显示出了一定的预测技巧;而澳洲气象局的POAMA2.4预测只在个别季度局部范围内具有技巧。使用BMA对订正后的单一模式预测进行集成可显著提高对中国季度降水预测的精度,相比单一模式预测,技巧得分为正值的网格百分率分别提高了13.3%和20.0%。     

Quantifying the impact of small variations in fracture geometric characteristics on peak rock mass properties at a mining project using a coupled DFN–DEM approach

Using field data from Agnico-Eagle’s Meliadine gold project located in Nunavut Territory in northern Canada, a coupled DFN–DEM approach was used to evaluate the rock mass mechanical properties at REV. Variability in the structural data gathered on site and the variability associated with the stochastic modeling process have an impact on discrete fracture model (DFN) properties. Through a sensitivity analysis, this paper assesses the influence of a variation in the DFN model input parameters’ values on the rock mass peak properties – uniaxial compressive strength, Young modulus and Poisson ratio. The results not only highlight the possibilities associated with DFN–DEM modeling in characterizing rock mass properties at the engineering scale, they also provide a systematic way to assess the critical structural parameters controlling the rock mass properties.     

基于肥满度-最大养殖收益的底播养殖虾夷扇贝(Patinopecten yessoensis)养殖容量评估及养殖区区划

养殖容量评估是合理规划养殖区的基础。基于虾夷扇贝养殖生态系统模型,模拟了2006年12月至2017年11月不同放苗密度下底播养殖虾夷扇贝的生长情况。在考虑肥满度对虾夷扇贝养殖收益的影响下,计算最大养殖收益及其对应的最适放苗密度和养殖容量,并通过最大养殖收益及其年际差异的聚类分析结果进行养殖区区划。结果表明:考虑扇贝肥满度的养殖收益能很好的抵消扇贝品质对养殖收益的影响;底播养殖虾夷扇贝的养殖容量和最适放苗密度有明显的时空差异,獐子岛和小长山岛之间并向长海海域东北部延伸的条带海域是高收益区;中收益区在高收益区南北两侧;低收益区位于研究区西北部和南中收益区南部;研究区南部由于饵料匮乏导致扇贝生长缓慢,为不适宜养殖区。开阔海域养殖容量也是有限的,片面增加放苗密度并不能达到增产增收的效果。研究结果可为合理规划和管理养殖区提供参考。