Above-ground carbon storage by urban trees in Leipzig, Germany: Analysis of patterns in a European city

Many aspects of global change, including carbon dioxide emissions, have been attributed to urban areas. On the other hand, cities have been found to provide valuable ecosystem services such as carbon storage. The aim of this study is to estimate the above-ground carbon storage in trees in the central European city of Leipzig and produce spatially explicit carbon storage maps. We used stratified random sampling across 19 land cover classes using 190 sample plots to measure carbon storage. In addition, we derived canopy cover from color-infrared orthophotos using an object-oriented approach and Random Forest machine learning. Finally, we apply an error assessment method that includes sampling error, but also uncertainty stemming from allometric equations, and that so far has only been applied to rural forests. The total above ground carbon stock of Leipzig was estimated using both land cover and canopy cover, which was more laborious than just using land cover but reduced the standard error. Canopy cover was approximately 19% of the city area. Leipzig's above-ground carbon storage was estimated to be 316,000 Mg C at 11 Mg C ha⁻¹. The distribution of carbon storage across the city showed the highest values at intermediate urbanization levels. Carbon storage in the city of Leipzig was in the lower range compared to cities in Europe, Asia and the USA, and our results indicate that great care should be taken when transferring values between cities. We provide spatially explicit and detailed maps of above-ground storage that can contribute to ecosystem services assessments.     

绿化带简化模型在风环境仿真中的应用

本文采用了一种新的绿化带模型进行阻力模拟计算,通过与常规的绿化带模拟方法进行对比,分析了两种不同的模拟方法对模拟结果的影响。首先对常规绿化带模型和新的绿化带模型的简化方式进行了简要说明,然后使用新的绿化带模拟方法建立了两个简化模型,再与常规的绿化带简化模型进行模拟计算对比,最后通过分析发现：使用新的绿化带模拟方法,可以设置与真实绿化带模型外形相似的LAD分布,能够获得更加合理的风场数据。     

核反应堆控制棒驱动机构管座Canopy焊缝间隙超差问题的分析

阳江核电厂1号机组控制棒驱动机构（CRDM）耐压壳部件在现场安装至反应堆压力容器顶盖管座后出现了Canopy焊缝间隙超差的问题,无法进一步完成施焊。介绍了上述Canopy焊缝间隙超差问题的分析及处理方法,并对该问题提出了相应的预防措施,为核电厂控制棒驱动机构耐压壳部件的安装提供可行的参考经验。     

Performance-Orientated Design Precursors and Potentials

Performance-oriented design is not without precedent. In the past, architecture responded with great sophistication and beauty to the need to preserve local resources and provide diverse and suitable conditions for human habitation. In the current context of escalating environmental and ecological changes, learning from precedents and developing their potential is becoming increasingly important. However, many architects refuse to look back in fear of returning to an imagined medieval condition, preferring instead to invest in the technologies that lie at the core of the environmental change and spatial and social division, which we may no longer be able to afford. In response to these circumstances, Michael Hensel examines the potential of past approaches to passive environmental modulation as a reworked spatial paradigm for design that interrelates material, spatial and environmental dynamics with dynamic patterns of habitation. Copyright © 2008 John Wiley & Sons, Ltd.     

Delineation of secondary succession mechanisms for tropical dry forests using LiDAR

Research suggests that secondary forest structure and composition subsequent to human disturbance could be related to wind or vertebrate dependent seed dispersal mechanisms. This paper examines the capability of a waveform LiDAR system (LVIS: LiDAR Vegetation Imaging System) to detect the location of wind-dispersed or vertebrate-dispersed forest patches in a mosaic of a secondary Tropical Dry Forest in the Santa Rosa National Park, Guanacaste, Costa Rica. Canopy-height estimations derived from LVIS data were used to identify and locate two types of dispersal-dependent arrangements of canopy heights: flat-topped (windborne seed dispersed) or dome-shaped (vertebrate-dispersed) fragments. Following identification, a Ripley's K indicator was used to compare the locations for each confirmed canopy type to those reported in existing maps. Results indicated that dome-shaped patches tended to be arranged in clusters at the middle of former pastures (far from older forests), and that flat-topped patches tended to be located adjacent to older forests, forming extensions from the old growth patches and at the downwind side of the slope. Such characteristics agree with the theoretical observation of the spatial configuration of vertebrate- and wind-dispersed fragments reported in the study site. Our findings demonstrate that processes controlling forest regeneration in the TDF can be successfully identified through LiDAR data.     

Barcelona Reset: Circuit of Ephemeral Architecture

During the summer of 2014, new life was injected into the auspicious squares and parks of the city centre of historic Barcelona by the Enric Miralles Foundation. This came in the form of celebrative temporary installations commissioned from teams, including among them Odile Decq, Yael Reisner and Peter Cook, Grafton Architects and Urban-Think Tank. Commemorating the 300th anniversary of the end of the siege of Barcelona, each group of collaborators was asked by the curators, architect Benedetta Tagliabue and theatre director Àlex Ollé, to create a structure that embodied a universal principle, such as diversity, democracy and identity. Benedetta Tagliabue describes the project.     

Multi-temporal vegetation canopy water content retrieval and interpretation using artificial neural networks for the continental USA

An inversion of linked radiative transfer models (RTM) through artificial neural networks (ANN) was applied to MODIS data to retrieve vegetation canopy water content (CWC). The estimates were calibrated and validated using water retrievals from AVIRIS data from study sites located around the United States that included a wide range of environmental conditions. The ANN algorithm showed good performance across different vegetation types, with high correlations and consistent determination coefficients. The approach outperformed a multiple linear regression approach used to independently retrieve the same variable. The calibrated algorithm was then applied at the MODIS 500 m scale to follow changes in CWC for the year 2005 across the continental United States, subdivided into three vegetation types (grassland, shrubland, and forest). The ANN estimates of CWC correlated well with rainfall, indicating a strong ecological response. The high correlations suggest that the inversion of RTM through an ANN provide a realistic basis for multi-temporal assessments of CWC over wide areas for continental and global studies.     

Changing Building Sites: Industrialisation and Automation of the Building Process

The introduction of robotics in construction is part of a much longer history of industrialisation and automation on the building site. Thomas Bock of the Technical University of Munich and Silke Langenberg of the University of Applied Sciences, Munich, highlight how the Industrial Revolution and the development of a transport infrastructure in the 18th and 19th centuries in Europe first triggered the shift in the building trade from a largely localised industry into a national and mechanised one, leading to the highly advanced automated construction techniques that continue to be developed in Japan and other Asian countries to this day.     

Local Design Responding to Urban Problems— The Metro-Forest Project,Bangkok

To respond to the urban problems and to increase forest areas in the city, an urban forest reflecting Bangkok’s former landscape was designed and constructed. To create diverse forest ecology and stimulate plant growth, Miyawaki’s ecological method to reforestation was implemented, and local tree species were used for pioneer planting as they had once established territorial populations around Bangkok. The layout of the species was carefully grouped, and planting locations were also carefully selected. The skywalk and observation tower were designed to minimize disturbance of the burgeoning forest and allow close-up views of the maturing canopy. This project is distinguished by strong design gestures that are well integrated into the landscape by using Bangkok’s design language, creating a space truly to inspire public awareness of urban forestry and the importance of environmental stewardship in Thailand.     

Spatial and temporal patterns of gap dominance by low-canopy lianas detected using EO-1 Hyperion and Landsat Thematic Mapper

Woody lianas are critical to tropical forest dynamics because of their strong influence on forest regeneration, disturbance ecology, and biodiversity. Recent studies synthesizing plot data from the tropics indicate that lianas are increasing in both abundance and importance in tropical forests. Moreover, lianas exhibit competitive advantages over trees in elevated CO₂ environments and under strong seasonal droughts, suggesting that lianas may be poised to increase not only in abundance but also in spatial distribution in response to changing climate. We used a combination of high-resolution color-infrared videography and hyperspectral imagery from EO-1 Hyperion to map low-lying lianas in Noel Kempff Mercado National Park (NKMNP) in the Bolivian Amazon. Evergreen liana forests comprise as much as 14% of the NKMNP landscape, and low-stature liana patches occupy 1.5% of these forests. We used change vector analysis (CVA) of dry season Landsat TM and ETM+ imagery from 1986 and 2000 to determine changes in liana-dominated patches over time and to assess whether those patches were regenerating to canopy forest. The spatial distribution of liana patches showed that patches were spatially aggregated and were preferentially located in proximity to waterways. The CVA results showed that most of the dense liana patches increased in brightness and greenness and decreased in wetness over the 14 years of the change analysis, while non-liana forest patches changed less and in more random directions. Persistent liana patches increased in area by an average of 59% over the time period. In comparison, large burned areas appeared to recover completely to canopy forest in the same time period. This suggests that the dense liana patches of NKMNP represent an alternative successional pathway characterized not by tree regeneration but rather by a stalled state of low-canopy liana dominance. This research supports hypotheses that liana forests can be a persistent rather than transitional component of tropical forests, and may remain so due to competitive advantages that lianas enjoy under changing climatic conditions.