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61.
Sofie Joosse Taylor Brydges 《Environmental Communication: A Journal of Nature and Culture》2018,12(5):686-700
The rise of social media radically broadens the sources and platforms used for environmental communication. Especially personal green blogs are worthy of study as they are spaces of everyday cultural politics through which people make sense of sustainability issues, and because they entail a radical break from conventional media in terms of legitimacy, form, and content of environmental communication processes. This paper studies the representation of sustainability on personal green blogs, and the communication processes through which these representations are constructed. It does so through a qualitative study of Swedish-language blogs. We study three blogs in-depth: a living experiment blog on sustainable food practices; a lifestyle blog centered around green family life; and a blog about consuming green beauty products. The analysis shows that all three blogs translate the complex landscape of sustainability to individual everyday practices. Yet, what these sustainability practices entail differs considerably between the blogs, ranging from a-political and doable lifestyle choices to an onset to radical redefining of consumption. Also, the communication processes on the blogs differ in quality and quantity. The paper uses these insights to reflect on the debates about how environmental communication is shaped by blogging and social media practices. 相似文献
62.
Jordan Wood Jonathan D. Ballou Taylor Callicrate Jeremie B. Fant M. Patrick Griffith Andrea T. Kramer Robert C. Lacy Abby Meyer Sara Sullivan Kathy Traylor-Holzer Seana K. Walsh Kayri Havens 《Conservation biology》2020,34(6):1416-1425
Maintaining a living plant collection is the most common method of ex situ conservation for plant species that cannot be seed banked (i.e., exceptional species). Viability of living collections, and their value for future conservation efforts, can be limited without coordinated efforts to track and manage individuals across institutions. Using a pedigree-focused approach, the zoological community has established an inter-institutional infrastructure to support long-term viability of captive animal populations. We assessed the ability of this coordinated metacollection infrastructure to support the conservation of 4 plant species curated in living collections at multiple botanic gardens around the world. Limitations in current practices include the inability to compile, share, and analyze plant collections data at the individual level, as well as difficulty in tracking original provenance of ex situ material. The coordinated metacollection framework used by zoos can be adopted by the botanical community to improve conservation outcomes by minimizing the loss of genetic diversity in collections. We suggest actions to improve ex situ conservation of exceptional plant species, including developing a central database to aggregate data and track unique individuals of priority threatened species among institutions and adapting a pedigree-based population management tool that incorporates life-history aspects unique to plants. If approached collaboratively across regional, national, and global scales, these actions could transform ex situ conservation of threatened plant species. 相似文献
63.
I. D. Tuck A. C. Taylor R. J. A. Atkinson M. E. Gramitto C. Smith 《Marine Biology》1997,129(3):505-511
Changes in the biochemical composition of the ovary of Nephrops norvegicus (L.) were examined throughout maturation at stations with fast and slow growing individuals in Scottish waters and in the
Mediterranean. Ovary index (ovary wt:total body wt) increased significantly with maturation. Lipid, protein and water content
of the ovary increased with maturation, while carbohydrate content decreased. Similar changes were also identified in the
hepatopancreas. Significant spatial differences in ovary and hepatopancreas composition were identified, which may be related
to whole-body growth rate. The ovary maturation scale commonly used for N. norvegicus was shown to reflect biochemically distinct stages in ovary development.
Received: 7 February 1997 / Accepted: 25 February 1997 相似文献
64.
Irena Rot-Nikcevic Christopher N. Taylor Richard J. Wassersug 《Behavioral ecology and sociobiology》2006,60(1):116-25
Tadpoles can alter their behavior, morphology, and life history in response to habitat change. Although chemical signals from
conspecifics or predators play an important role in tadpole habitat assessment, little is known about the role of visual cues
and the extent to which tadpoles rely on their vision for intraspecific social assessment. The aim of our experiments was
to determine whether larval anurans use visual images of other tadpoles as indicators of density and to analyze how, and to
what extent, images of conspecifics alone affect tadpole development, growth, and behavior. To assess this, we raised both
Rana sylvatica and Bufo americanus tadpoles in aquaria with either quarter- or half-mirrored walls. Both physically increased density and increased density
simulated with mirrors decreased tadpole growth and developmental rates, and increased activity in Rana tadpoles. Bufo tadpoles did not significantly alter their growth and development in response to visually increased density. Only true, i.e.,
physically, increased density had an effect on growth and activity in Bufo tadpoles. Our data show that images of conspecifics are used as visual cues by Rana tadpoles and can induce phenotypically plastic changes in several traits. This response to visual cues is taxon-specific.
An erratum to this article can be found at 相似文献
65.
A ciliate red tide at Barrow,Alaska 总被引:1,自引:0,他引:1
In September 1968 the first occurrence of extensive red water in the Arctic Ocean in the vicinity of Point Barrow, Alaska, was recorded. The organism causing this water discoloration was a fairly large (100 to 150 ) ciliated protozoan, with chlorophyll-containing endosymbionts. This ciliate, which is not identical to the commonly reported Mesodinium or Cyclotrichium species, is described in this paper, but cannot be identified with any organism described in the literature. Concentrations of dissolved inorganic nutrients and trace metals were determined on water samples obtained from the red water and also in the clear water adjacent to it. These data are discussed relative to the hydrographic conditions in the Chuckchi Sea around Point Barrow. A direct species' analysis by microscopic methods indicated that the plankton were quite similar in all the water samples except for the aforementioned red ciliate, which accounted for over 90% of the total cellular organic carbon in the samples from the red water. Chemical analyses indicated that the red tide ciliate contained approximately 51% protein, 33% lipid, 8% carbohydrate, 0.2% chlorophyll a, and 1.2% DNA. 相似文献
66.
67.
The distribution of the cladoceran Podon polyphemoides (Leuckart) in the Chesapeake Bay (USA) estuarine system was determined by a quantitative pump sampling method, and the patterns of abundance were correlated with temperature and salinity distributions. The species was seasonally recurrent, with distinct population maxima in the central portion of the bay. Population densities in excess of 60,000 podonids/m3 have been recorded. The podonids first appeared in the spring in the shallow tributaries, when water temperatures near the bottom reached 6°C. The vernal populations disappeared when summer temperatures exceeded 27°C, but reappeared in the fall as the water cooled. The species was euryhaline and eurythermal in its distribution, but the greatest concentrations were attained within relatively narrow zones of temperatures between 11o and 26°C, and salinities between 8 and 18. The production of males, sexual females and sexual eggs occurred both in the spring and the fall between the thermal limits of 11o and 17°C. 相似文献
68.
Metabolic responses of the prawns Palaemon elegans and P. serratus (Crustacea: Decapoda) to acute hypoxia and anoxia 总被引:2,自引:0,他引:2
Using prawns, Palaemon elegans (Rathke) from intertidal pools on the Isle of Cumbrae, Scotland, and P. serratus (Pennant) from the subtidal at Plymouth, England, some metabolic responses to hypoxia and anoxia have been studied. P. elegans was found to have a greater tolerance of severe hypoxia than P. serratus. Tolerance of totally anoxic conditions, however, was limited to only 4 h in P. elegans and to approximately 1 h in P. serratus. exposure to moderate hypoxia (30 torr) resulted in little change in the concentration of L-lactate in the blood or in the tissues of either P. elegans or P. serratus. When exposed to extreme hypoxia (10 or 5 torr for P. elegans), however, there was a progressive increase in the concentration of L-lactate in the blood and in the tissues of both species. After normoxic conditions had been restored, the concentration of L-lactate in the blood and in the tissues returned to normal resting levels more rapidly in P. elegans than in P. serratus. Under hypoxic conditions, both P. elegans and P. serratus showed an increase in the concentration of blood glucose and a slight reduction in the glycogen content of the tissues. The concentrations of blood glucose and of tissue glycogen returned to normal levels within 6 h of the prawns being returned to normoxic conditions. The results of an in situ study in April and August 1986 to examine the metabolic responses of P. elegans to the hypoxic conditions normally experienced in high-shore rock pools are also presented. The ecological significance of the differing abilities of these species to survive hypoxic exposure is discussed. 相似文献
69.
Fucus distichus L. was collected near Vancouver, Canada, in late fall and early winter, 1981. The effects of the forms of nitrogen (nitrate, ammonium or urea) and periodic exposure to air on growth, rhizoid development and nitrogen uptake in germlings was investigated. Gamete release, fertilization, germination and germling growth had no requirement for a specific form of nitrogen. Periodic exposure to air increased secondary rhizoid development twofold. Nitrate and ammonium uptake rates of the germlings were higher than for the mature thalli (20 to 40 times for nitrate and 8 times for ammonium), while the halfsaturation constant (K
s) values for nitrate were similar (1 to 5 M). The germlings showed saturable uptake kinetics but the mature thalli did not. When germlings were exposed to air it caused a 70% decrease in nitrate uptake, but not change in ammonium uptake. Ammonium uptake in the mature thalli was proportional to the ambient ammonium concentration. Nitrate uptake in the mature thalli appeared to follow saturation kinetics at low nitrate concentrations, but showed a non-saturable component at concentrations greater than 10 M. Presence of ammonium inhibited nitrate uptake by the mature plants but not by the germlings. 相似文献
70.
Desulfobacter sp. (Strain 3ac10), an acetate-utilizing sulphatereducing bacteria, was added to sterile marine pore water spiked with 14C-acetate, and changes in both the natural acetate pool and the added 14C-acetate were measured over time. Initially, both the added 14C-acetate and the chemically measured acetate were rapidly mineralized, but then the rate of removal decreased and a significant amount (approximately 20%) of both 14C-acetate and chemically measured acetate remained unmetabolised. In a replicate experiment, approximately 50% of the acetate was not metabolised. Kinetic analysis of the data indicated that there were two pools of acetate in the original pore water, a biologically available pool (which is rapidly metabolised) and a recalcitrant pool (which is only very slowly metabolised). Addition of 14C-acetate after the biologically available acetate had been removed resulted in rapid removal of the added acetate but no change in the recalcitrant acetate pool. The implications of this data to radiolabelled techniques of measuring in situ acetate turnover are discussed. 相似文献