Towards a Paradigmatic Shift in Sustainability Studies: A Systematic Review of Peer Reviewed Literature and Future Agenda Setting to Consider Environmental (Un)sustainability of Digital Communication

The materiality of digital communication inflicts substantial environmental damage: the extraction of resources needed to produce digital devices; the toxicity of e-waste; and the rapidly increasing energy demands required to sustain data generated by digital communication. This damage, however, is paradoxically under-theorized in scholarship on environmental sustainability. Despite the existing critique of the “techno-fix” approach in sustainability studies, digitization – and digital communication in particular – continue to be celebrated as the tool for environmental sustainability; an approach we coin “digital solutionism.” The article presents the first systematic review of the literature to map the implicit assumptions about the relationships between digital communications and environmental sustainability, in order to examine how digital solutionism manifests, and why it persists. We propose a concept matrix that identifies the key blind spots with regards to environmental damages of the digital, and call for a paradigmatic shift in environmental sustainability studies. An agenda for future research is put forward that advocates for the following: (1) a systematic account of material damages of devices, platforms and data systems adopted into sustainability research and practice, resulting in changes in both research framing and methodological foundations; (2) a reconceptualization and denaturalization of the digital itself as a promising solution; (3) a theoretical dialogue between sustainability studies and environmental communication. (4) an expansion of environmental communication as a field, from focusing on the communication aspect of environmental change to include the environmental footprint of communication itself.     

黄土区陡坡侵蚀过程试验研究

通过室内放水冲刷试验,结果表明,陡坡单宽径流能耗与单宽径流产沙率之间存在以下线性关系:Dr=18.672(ΔE - 0.751),说明土壤的可蚀性参数为18.672 g/J,发生坡面细沟侵蚀的临界径流能耗为0.751 J/(ms)。坡面单宽径流能耗随流量增大而增加,随坡度变化呈抛物线趋势,临界坡度出现在21和24之间。坡面上各段面单宽径流能耗均随流量的增大而增加,随着坡度逐渐增加,坡面上部段面能耗渐增,中部段面渐减,下部较稳定。坡面各段面侵蚀产沙也有类似特征。此研究对于深入了解黄土高原陡坡土壤侵蚀过程和机理具有重要意义。     

Foraging in the seed-harvester ant genus Pogonomyrmex: are energy costs important?

Energy intake and expenditure on natural foraging trips were estimated for the seed-harvester ants, Pogonomyrmex maricopa and P. rugosus. During seed collection, P. maricopa foraged individually, whereas P. rugosus employed a trunk-trail foraging system. Energy gain per trip and per minute were not significantly different between species. There was also no interspecific difference in energy cost per trip, but energy cost per minute was lower for P. maricopa foragers because they spent on average 7 min longer searching for a load on each trip. Including both unsuccessful and successful foraging trips, average energy gain per trip was more than 100 times the energy cost per trip for both species. Based on this result, we suggest that time cost incurred during individual foraging trips is much more important than energy cost in terms of maximizing net resource intake over time. In addition, because energy costs are so small relative to gains, we propose that energy costs associated with foraging may be safely ignored in future tests of foraging theory with seed-harvesting ant species.     

Is Current Consumption Excessive? A General Framework and Some Indications for the United States

Abstract:  Many prior studies have explored the implications of human population growth and environmentally problematic technologies for biodiversity loss and other forms of environmental degradation. Relatively few, however, have examined the impacts of the level and composition of consumption. We offer a framework that shows how the level and composition of a society's total consumption relate to the uses of various forms of capital and to the sustainability of natural resources and human well-being. We relate the framework to two main approaches—top–down macro studies and bottom–up computer models—for measuring whether overall consumption in the United States satisfies a sustainability requirement. Existing top–down studies have shortcomings that bias their results toward optimism, and current computer simulation models, although strong on revealing biophysical outcomes, are limited in their ability to evaluate impacts on human well-being. Although some ambiguities arise in determining whether overall consumption in the United States is excessive, our conclusions regarding the composition of U.S. consumption are unambiguous. Distorted consumption patterns and associated production methods lead to excessively rapid natural resource depletion; greater conservation would yield gains to current and future generations that more than compensate for the sacrifices involved. Public policies that deal with the composition problem not only would help conserve natural resources and improve current welfare but also would reduce the costs of meeting the goal of sustainability.     

低温对日本沼虾耗氧率、排氨率和Na+/K+ ATPase比活力的影响

在低温和室温条件下，测定了两种规格日本沼虾(Macrobrachium nipponens)的耗氧率、排氨率和Na^ ／K^ ATPase比活力．结果表明，低温条件下日本沼虾的耗氧率和排氨率均低于室温，且与体重呈负相关；而Na^ ／K^ ATPase比活力高于室温，且与体重呈正相关．表4参21     

南京住宅小区雨水回用方案技术经济分析

分析了南京城区雨水资源量和杂用水需求量的关系，通过示例，提出了住宅小区4种雨水回用方案，进行工程造价、雨水处理成本等方面的技术经济比较，结果方案3最优。     

Does begging affect growth in nestling tree swallows,<Emphasis Type="Italic"> Tachycineta bicolor</Emphasis>?

Much of the theoretical work on the evolution of begging assumes this elaborate display is costly. The evidence for an energetic cost to begging has, however, been equivocal. Metabolic studies on nestling birds suggest that begging requires minimal energy, but some growth studies have shown that excess begging reduces growth rates. One difficulty in interpreting these results is that metabolic and growth studies have each been performed on different species. Here, we test whether high begging frequencies depress growth in nestling tree swallows, Tachycineta bicolor, a species in which the metabolic cost of begging has been measured. When we compared the growth of nestlings stimulated to beg at either high or low frequencies, we found no significant differences in their mass gained, wing growth or portion of ingested energy devoted to begging either during the experimental period or in the 24 h following the end of the experiment. We also found no significant relationship between begging intensity and growth measurements. The results of our study are consistent with previous metabolic studies on this species suggesting that the energetic cost of begging is relatively low. More generally, evidence for a fitness cost of begging via decreased growth is equivocal.Communicated by J. Dickinson     

开花前后变水条件对春小麦的补偿效应

在防雨棚内的盆栽实验条件下，研究了4种梯度的10种不分组合对红芒麦和宁春10号产量及耗水量等的影响。结果表明，试验期间充分灌水，轻度，中度，重度干旱处理，随着干旱程度的加剧，株高，干物质积累，产量，耗水量都逐渐减少；红芒麦灌浆期不同程度的,匀有利于产量的形成，促进物质运输，提高千粒重，同时减少水分消耗，提高WUE；孕穗期干旱处理后，灌浆期复水，会造成减产，和灌浆期相比，孕穗期是水分的敏感的时期，而灌浆期对水分亏缺不敏感，两种小麦相比较，宁春10号耗水量大，产量低，抗旱性较强，图2表2参7     

Determinants of chorus tenure in barking treefrogs (Hyla gratiosa)

In all species of anuran amphibians studied to date, male mating success is positively correlated with male chorus tenure (the number of nights that a male is present in breeding aggregations), yet males spend only a small portion of the total breeding season in choruses. Three hypotheses might explain abbreviated chorus tenure in anuran amphibians: (1) mortality, (2) energy limitations, and (3) movement among choruses. I tested these hypotheses in a study of the barking treefrog (Hyla gratiosa), a species with very abbreviated chorus tenure. Mortality accounted for the short tenures of some males: an estimated 20% of males died while calling in the chorus. Energy limitations were an important determinant of chorus tenure. Males lost weight over successive nights in the chorus, and males with longer chorus tenures were in better condition on their first night in the chorus, lost condition more slowly, and were in poorer condition on their last night in the chorus than were males with shorter chorus tenures. Males that I fed crickets as they left the chorus returned sooner and for more nights than did control (unfed) males. Movement between ponds did not explain abbreviated chorus tenure: less than 16% of the males called at more than one pond, and these males increased their chorus tenures by a median of only 2.5 nights by calling in another chorus. Thus, abbreviated chorus tenure in H. gratiosa appears to be primarily the result of energy limitations, with mortality playing a secondary role.     

煤矿井下气候参数和劳动强度对矿工生理参数影响的研究

对机械化采煤工作面的采煤机司机和支柱工的劳动心率和能量代谢进行了现场实测。就气候参数和劳动强度对作业人员的生理参数影响进行了模拟实验,取得一些实验研究成果。对改善劳动条件和作业环境,提高生产效率,保护井下矿工的身心健康与安全,提供了科学依据。