589 research outputs found
Means for accommodating large overstrain in lead wires
An electrical wire is reported along whose length loops are formed at intervals and retained in a plastic capsule that allows unfolding of the loop when tension is exerted on the opposite ends of the wire. The capsule is formed by encompassing each loop with a sleeve of heat shrinkable synthetic plastic material which overlaps the loop and heat shrinking the overlapping portions. Thus, a length of electrical wire is formed which stores extra lengths of wire in the quantity needed to match the expected stretching of materials or elements such as ropes, cords and the like of high elongation to which the electrical wire may be attached
Soil microarthropod community dynamics in extensive green roofs
Green roofs are of increasing interest to ecologists, engineers and architects, as cities grow and aim to become more sustainable. They could be exploited to improve urban biodiversity and ecosystem services, yet almost nothing is known about them from a soil community ecology perspective, despite how critical soil food webs are to ecosystem functioning. This paper provides the first comprehensive study incorporating the annual cycle of green roof soil microarthropods.Microarthropod communities were monitored over 14 months on two extensive green roofs. Abiotic factors, including substrate moisture, were recorded, as were biotic factors such as plant and mycorrhizal colonisation. Microarthropod interactions with these variables were then examined.Microarthropod diversity was low overall, with a few dominant species peaking seasonally. On occasion, total abundance was comparable to other early successional soils. The majority of species present were drought tolerant collembola and xerophillic mites, suggesting that moisture levels on green roofs are a major limiting factor for soil microarthropods.Our results suggest that the microarthropod community present in extensive green roof soils is impoverished, limiting the success of above-ground flora and fauna and ultimately the success of the roof as an urban habitat. We conclude that green roof building guidelines should incorporate soil communities in their design and should aim to be heterogeneous at the roof and landscape level, for the purpose of supporting soil biodiversity and creating sustainable habitats
Understanding and Applying Ecological Principles in Cities
Renaturing cities requires a thorough understanding of how plants and animals interact with the urban environment and humans. But cities are a challenging environment for ecologists to work in, with high levels of heterogeneity and rapid rates of change. In addition, the hostile conditions often found in cities mean that each city, and region of a city, can have their own unique geographical context. In this chapter, we contrast urban ecological research in the UK and Brazil, to demonstrate the challenges and approaches needed to renature cities. In so doing, we provide a platform for global transferability of these locally contextualised approaches. The UK has a long history of urbanisation and, as a result of increasing extinction debts over 200 years, well-established urban ecological research. Research is generally focused on encouraging species back into the city. In contrast, Brazil is a biodiversity hotspot with relatively rich urban flora and fauna. This rich ecosystem is imperilled by current rapid urbanisation and lack of support for urban nature by city-dwellers. By working together and transferring expertise, UK and Brazilian researchers stand a better chance of understanding urban ecological processes and unlocking renaturing processes in each location. We present one such method for applying ecological knowledge to cities, so-called Ecological Engineering, in particular by discussing ecomimicry—the adaptive approach needed to apply global ecological principles to local urban challenges. By reading the ecological landscape in which urban developments sit and applying tailored green infrastructure solutions to new developments and greenspaces, cities may be able to reduce the rate at which extinction debt is accumulated
Museum of Futures: Pandemic Pivots
The Museum of Futures: Pandemic Pivots is a work of collaborative foresight and participatory futures. In 2020, it is clear that we are living in post-normal times. A summer of catastrophic bushfires followed by a global pandemic has shown us all the importance of thinking about the future. In this exhibition, ten communities explored how they hoped that life in Sydney would pivot after the Covid-19 pandemic. Their ideas were given to nine Australian artists to interpret into works that you see in this exhibition. Alongside each work you will also see the 'history' of what happened to make this future occur
Multi-scale Habitat Use of Male Ruffed Grouse in the Black Hills National Forest
Ruffed grouse (Bonasa umbellus) are native upland game birds and a management indicator species (MIS) for aspen (Populus tremuloides) in the Black Hills National Forest (Black Hills). Our objective was to assess resource selection of male ruffed grouse to identify the most appropriate scale to manage for aspen and ruffed grouse in the Black Hills. During spring 2007 and 2008, we conducted drumming surveys throughout the central and northern Black Hills to locate used and unused sites from which we compared habitat characteristics at increasing spatial scales. Aspen with \u3e70% overstory canopy cover (OCC) was important to the occurrence of ruffed grouse across all spatial scales, but was most influential within 1600 m of drumming sites. Probability of a site being used was maximized when 20% of the 1600-m scale (~804 ha) had aspen with \u3e70% OCC. Ruffed grouse also selected for areas with many small, regular shaped patches of aspen over those with few large patches. At the smallest scale evaluated of 200 m (~12.5 ha), ruffed grouse selected drumming logs in close proximity to high stem densities of aspen with a minimal presence of roads. Ponderosa pine (Pinus ponderosa) had a negative influence on site selection at the 400-m (~50 ha), 1600-m (~804 ha), and 4800-m (~7200 ha) scales. Management for ruffed grouse in the Black Hills as the MIS for aspen should focus on increasing the extent of aspen with a goal of at least 20% occurrence on the landscape. Management efforts also should incorporate multiple age and size classes of aspen with an emphasis on enhancing early successional habitat to provide valuable cover through increased stem densities
Museum of Futures: Pandemic Pivots
The Museum of Futures: Pandemic Pivots is a work of collaborative foresight and participatory futures. In 2020, it is clear that we are living in post-normal times. A summer of catastrophic bushfires followed by a global pandemic has shown us all the importance of thinking about the future. In this exhibition, ten communities explored how they hoped that life in Sydney would pivot after the Covid-19 pandemic. Their ideas were given to nine Australian artists to interpret into works that you see in this exhibition. Alongside each work you will also see the 'history' of what happened to make this future occur
Museum of Futures: Pandemic Pivots
The Museum of Futures: Pandemic Pivots is a work of collaborative foresight and participatory futures. In 2020, it is clear that we are living in post-normal times. A summer of catastrophic bushfires followed by a global pandemic has shown us all the importance of thinking about the future. In this exhibition, ten communities explored how they hoped that life in Sydney would pivot after the Covid-19 pandemic. Their ideas were given to nine Australian artists to interpret into works that you see in this exhibition. Alongside each work you will also see the 'history' of what happened to make this future occur
The Wild Turkey in South Dakota
This bulletin provides an extensive look at the wild turkey in South Dakota
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