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91.
Joe F. Bozeman III Shauhrat S. Chopra Philip James Sajjad Muhammad Hua Cai Kangkang Tong Maya Carrasquillo Harold Rickenbacker Destenie Nock Weslynne Ashton Oliver Heidrich Sybil Derrible Melissa Bilec 《Journal of Industrial Ecology》2023,27(2):382-394
Now is the time to refocus efforts in urban research and design. A changing climate and extreme weather events are presenting unique challenges to urban systems around the world. These challenges illuminate the social barriers that accompany disruptive events such as resource inequities and injustices. In this perspective, we provide three research priorities for just and sustainable urban systems that help to address these matters. The three research priorities are: (1) social equity and justice, (2) circularity, and (3) digital twins. Conceptual context and future research directions are provided for each. For social equity and justice, the future directions are mandatory equity analysis and inclusionary practices, understanding and reconciling historical injustices, and intentional integration with diverse community stakeholders. For circularity applications, they are better metrics for integration, more robust evaluation frameworks, and dynamic modeling at multiple spatial and temporal scales. Future directions for digital twins include developing principles to reduce complexity, integrating model and system components, and reducing barriers to data access. These research priorities are core to meeting several of the United Nations Sustainable Development Goals (i.e., 1—No Poverty, 8—Decent Work and Economic Growth, 10—Reduced Inequalities, and 11—Sustainable Cities and Communities). Useful social and technical matters are discussed throughout, where we highlight the importance of prioritizing localized research efforts, provide guidance for community-engaged research and co-development practices, and explain how these priorities interact to align with the evolving field of industrial ecology. 相似文献
92.
Jennifer D. Russell Sahra Svensson-Hoglund Jessika Luth Richter Carl Dalhammar Leonidas Milios 《Journal of Industrial Ecology》2023,27(3):845-855
Research into repair within the circular economy (CE) typically focuses on technical aspects of design, policy, and markets, and often assumes simplified conditions for the user/owner and the product system to explain the barriers to scaling repair activities. However, factors occurring at pre-use stages of the product's life cycle can significantly influence whether, and to what extent, repair is viable or possible, that is, warranty duration, after-sale service provision, and access to necessities. The passing of time can directly and indirectly affect the ability, difficulty, and thus, the likelihood of repair activities being performed at each stage of the product's life cycle. Drawing from the literature and applying inductive systems-thinking tools, we propose a framework for considering the “System of Repairability.” We delineate how the passing of time (temporal dimensions) affects one's ‘‘ability to repair,’’ as a product progresses through different life cycle phases (i.e., breakdown vs. repair vs. disposal), and the point(s) at which the repair is considered or attempted (i.e., year of usage). By integrating life cycle and temporal (time-based) dimensions into a broad System of Repairability framework, we clarify relevant interconnections, iterations, sequences, and timing of decision points, stakeholders, and necessary conditions to facilitate an outcome of successful repair at the individual level, and thus intervention strategies for scaling repair within CE. We discuss how a policy mix can address the life cycle of products and the repair system more holistically. We conclude with a future outlook on how temporal dimensions can inform policy strategies and future research. 相似文献
93.
Marta Royo Vicente Chulvi Elena Mulet Laura Ruiz-Pastor 《Journal of Industrial Ecology》2023,27(2):562-586
One of the approaches followed by the circular economy (CE) to achieve sustainability through design is product life extension. Extending the life of products to make them useful for as long as possible is a means to reduce waste production and materials consumption, as well as the related impacts. For designers, conceptualizing products in a way that allows them to be used for longer is a challenge, and assessing how well they extend their lifespan can be helpful when it comes to choosing the best proposal. In this paper, 70 tools and methods related to eco-design and circular economy are studied to determine how many of them consider parameters related to life extension and which can be applied in the early stages of design. The results of the analysis show that most of the existing tools and methods are applicable to developed products, and only a few of them take into account parameters related to extending the useful life. Of the 70 tools and methods, only 14 include some parameter related to life extension and are applicable to concepts. CE toolkit, Eco-design PILOT, CE Designer, Circularity Assessment tool, Circularity Potential Indicator and Circular Design Tools take into consideration eight or more parameters to assess life extension in concepts. This will help designers select the most appropriate and will indicate the need for more complete tools to consider useful life extension in the early stages of design and thus enhance the selection of more sustainable products. 相似文献
94.
在扬州地区,稻象虫一年发生1代。以老熟幼虫越冬,其越冬存活率免耕田>少耕田>常规耕田,肾发育的高低温临界点为38.16℃和9.84℃,最适发育温度26.52℃,有效积温117.8日度,每头稻虫产卵卵3-29粒,平均18.8粒;成虫羽化后17-31天为产卵盛期;产卵孔平均高度为4.1±1.5cm,水象下卵孔占28.6%:产卵孔与取食孔特征不同.卵期7±1.8天.成,幼虫的各群空间格局基本属密集颁布(仅x^-≤3时的成虫种群为随机分布).单季稻的为害重于双季稻;沙质土壤的发生量多于粘壤土,稻—麦(油菜)两熟制田的为害显重于稻-稻麦(油菜)三熟制田。 相似文献
95.
Jan Streeck Stefan Pauliuk Hanspeter Wieland Dominik Wiedenhofer 《Journal of Industrial Ecology》2023,27(2):436-456
Dynamic material flow analysis (dMFA) is widely used to model stock-flow dynamics. To appropriately represent material lifetimes, recycling potentials, and service provision, dMFA requires data about the allocation of economy-wide material consumption to different end-use products or sectors, that is, the different product stocks, in which material consumption accumulates. Previous estimates of this allocation only cover few years, countries, and product groups. Recently, several new methods for estimating end-use product allocation in dMFA were proposed, which so far lack systematic comparison. We review and systematize five methods for tracing material consumption into end-use products in inflow-driven dMFA and discuss their strengths and limitations. Widely used data on industry shipments in physical units have low spatio-temporal coverage, which limits their applicability across countries and years. Monetary input–output tables (MIOTs) are widely available and their economy-wide coverage makes them a valuable source to approximate material end-uses. We find four distinct MIOT-based methods: consumption-based, waste input–output MFA (WIO-MFA), Ghosh absorbing Markov chain, and partial Ghosh. We show that when applied to a given MIOT, the methods’ underlying input–output models yield the same results, with the exception of the partial Ghosh method, which involves simplifications. For practical applications, the MIOT system boundary must be aligned to those of dMFA, which involves the removal of service flows, sector (dis)aggregation, and re-defining specific intermediate outputs as final demand. Theoretically, WIO-MFA, applied to a modified MIOT, produces the most accurate results as it excludes massless and waste transactions. In part 2 of this work, we compare methods empirically and suggest improvements for aligning MIOT-dMFA system boundaries. 相似文献
96.
97.
Aims
Woody plant encroachment is a widespread phenomenon affecting treeless or sparsely treed habitats. We aimed to determine the extent and timing of tree and shrub encroachment into rock barrens of eastern Ontario over the last century, and to assess implications for their ongoing management.Location
Queen's University Biological Station in the Frontenac Arch ecoregion.Methods
We quantified the extent of change in woody vegetation in 290 rock barrens using aerial photography from 1925, 1965, and 2008. Composition and structure of woody plant communities in 10 barrens was subsequently quantified in the field using plot-based sampling. Cores or cross-sections were obtained from individuals >1.5 m height and dendrochronological techniques were used to determine their age and identify temporal patterns of any woody encroachment.Results
Aerial photography indicated that the mean proportion of woody plant cover in barrens increased 22.5% from 1925 to 2008. Dendroecological analysis supported this. Few trees were present prior to 1900 and most established since 1960. Fraxinus americana, Juniperus virginiana, and Juniperus communis were the most common woody species colonizing the barrens. Remnants of large Pinus strobus stumps with extensive charring were found in 90% of the sampled barrens at a mean density of 22.6 stumps ha−1.Conclusions
Rock barrens on the Frontenac Arch have changed substantially over the past century; gradually being colonized by trees and shrubs and losing their distinctly open character. Active management — including prescribed fire and mechanical thinning — may be necessary if there is a desire to maintain these barrens and the rare species they support as components of the region's biodiversity. However, identification of a reference state for restoration is complicated by the fact that the structure and composition of these habitats were undoubtedly altered by European land clearance in the 19th century, and that some of these areas likely existed as pine woodlands before that. 相似文献98.
James Richardson Alexander C. Lees Eliot T. Miller Stuart J. Marsden 《Ecology letters》2023,26(8):1301-1313
Understanding the composition of urban wildlife communities is crucial to promote biodiversity, ecosystem function and links between nature and people. Using crowdsourced data from over five million eBird checklists, we examined the influence of urban characteristics on avian richness and function at 8443 sites within and across 137 global cities. Under half of the species from regional pools were recorded in cities, and we found a significant phylogenetic signal for urban tolerance. Site-level avian richness was positively influenced by the extent of open forest, cultivation and wetlands and avian functional diversity by wetlands. Functional diversity co-declined with richness, but groups including granivores and aquatic birds occurred even at species-poor sites. Cities in arid areas held a higher percentage of regional species richness. Our results indicate commonalities in the influence of habitat on richness and function, as well as lower niche availability, and phylogenetic diversity across the world's cities. 相似文献
99.
T. W. Cronin N. J. Marshall R. L. Caldwell 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1993,172(3):339-350
1. | We examined the retinas of 2 species of stomatopods in the superfamily Squilloidea, Cloridopsis dubia and Squilla empusa, and 2 species of the super-family Lysiosquilloidea, Coronis scolopendra and Lysiosquilla sulcata, using microspectrophotometry in the visible region of the spectrum. |
2. | Retinas of all species included numerous photostable pigments, such as green reflecting pigment, hemocyanin, colored oil droplets, and vesicles. Both lysiosquilloid species also had intrarhabdomal filters within specialized photoreceptors of the midband. |
3. | Squilloid species contained a single visual pigment throughout all photoreceptors, with peak absorption at medium wavelengths (near 515nm). Retinas of lysiosquilloids contained a diversity of visual pigments, with estimated max values ranging from 397 to 551 nm. |
4. | Spectral sensitivity functions were estimated for the lysiosquilloid species based on estimates of visual pigment nax, photoreceptor dimensions, and specific absorbances of the visual pigments and intrarhabdomal filters. Ommatidia of midband Rows 1 to 4 contained pairs of narrowly tuned spectral receptors, appropriate for spectral discrimination, while ommatidia of midband Rows 5 and 6, and all peripheral ommatidia, had broad spectral sensitivity functions. |
5. | Lysiosquilloid stomatopods have retinas that closely resemble those of gonodactyloids both structurally and in their visual pigment diversity. In contrast, squilloids have retinas that are much simpler. These differences appear to be related to the habitats and activity cycles of species belonging to the 3 major superfamilies of stomatopod crustaceans. |
100.
P. A. Chave 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1993,2(2):65-71
The paper describes the regulatory functions of a new body set up in England and Wales for the management of water pollution, the National Rivers Authority. It outlines proposals for a new water quality classification scheme incorporating biological monitoring as an integral part, and describes other areas of pollution control where biology could be used with advantage. The derivation of statutory water quality objectives as a new concept in the management of natural waters is described, together with an indication of some of the legal mechanisms available to the NRA to ensure that the objectives are met. 相似文献