Termite sensitivity to temperature affects global wood decay rates.

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface

Invertebrate life-history trade-offs and dispersal across a pond-permanence gradient

Flexible life-history traits and dispersal may allow generalist populations to persist across a range of habitats despite experiencing contrasting selection pressures. Invertebrates exploiting temporary ponds must develop quickly and disperse as adults, or have wide environmental tolerances. Conversely, permanent-pond invertebrates must avoid a suite of predators (e.g., fish and dragonflies). This gradient of pond permanence can result in life-history trade-offs that influence fitness, population dynamics, and genetic structure. In addition, recruitment between habitats may balance juvenile life-history trade-offs and be crucial to sustain generalist invertebrate populations in ponds with unpredictable hydrology. Through a multi-year survey of three pond complexes in the Canterbury high-country and a series of mesocosm experiments using two generalist pond invertebrates, Xanthocnemis zealandica damselflies and Sigara arguta waterboatmen, I found these two species had alternative life-history strategies that influenced their distributions across the pond-permanence gradient. With longer juvenile development, X. zealandica benefited from flexible life-history traits: temporary-pond X. zealandica had accelerated development and short-term desiccation tolerance, but were excluded from ponds with long dry periods, whereas, permanent-pond X. zealandica had extended development and predator avoidance behaviours (e.g., reduced movement and refuge-use). In contrast, S. arguta had an opportunistic life-history strategy with a fixed, rapid development response that allowed them to inhabit more temporary ponds, but they were intolerant of drying and limited to permanent ponds that contained shallow refuges from fish. These results illustrate how alternative life-history strategies enabled two generalist species to achieve broad realised niches. Recruitment between habitats also appeared to be important for balancing trade-offs and maintaining meta-populations across the pond-permanence gradient. To evaluate the importance of X. zealandica dispersal among and within pond complexes I used microsatellite analyses. While there was unique genetic population structure between the North and South Islands, at lower spatial scales there was little variability in genetic diversity and limited genetic structure in populations, likely due to gene flow among different habitat types. Overall, this work shows how an interaction of juvenile strategies and adult dispersal could reduce life-history trade-offs, resulting in weak selection pressures across an unpredictable disturbance gradient. Whether increasingly unpredictable hydrological patterns under climate-warming favour generalist species will likely depend on how well generalist life-history traits and dispersal allow exploitation of a range of habitat types and resilience to variable selection pressures. Higher mean summer rainfall in New Zealand may allow both species to exploit more temporary ponds, whereas longer dry periods between extreme precipitation events could limit X. zealandica distributions. Thus, species with generalist strategies are likely to be favoured under warming, but their specific life-history strategies will likely promote or limit their ability to exploit more unpredictable habitats

Seasonal differences in climate change explain a lack of multi-decadal shifts in population characteristics of a pond breeding salamander.

There is considerable variation among studies that evaluate how amphibian populations respond to global climate change. We used 23 years of annual survey data to test whether changes in climate have caused predictable shifts in the phenology and population characteristics of adult spotted salamanders (Ambystoma maculatum) during spring breeding migrations. Although we observed year-to-year correlation between seasonal climate variables and salamander population characteristics, there have not been long-term, directional shifts in phenological or population characteristics. Warm winters consistently resulted in early migration dates, but across the 23-year study, there was no overall shift towards warmer winters and thus no advanced migration timing. Warm summers and low variability in summer temperatures were correlated with large salamander body sizes, yet an overall shift towards increasing body sizes was not observed despite rising summer temperatures during the study. This was likely due to the absence of long-term changes of within-year variation in summer temperatures, which was a stronger determinant of body size than summer temperature alone. Climate-induced shifts in population characteristics were thus not observed for this species as long-term changes in important seasonal climate variables were not observed during the 23-years of the study. Different amphibian populations will likely be more resilient to climate change impacts than others, and the probability of amphibians exhibiting long-term population changes will depend on how seasonal climate change interacts with a species' life history, phenology, and geographic location. Linking a wide range of seasonal climatic conditions to species or population characteristics should thus improve our ability for explaining idiosyncratic responses of species to climate change

Attitudes towards temporary and perennial rivers

Summary statistics for responses of anonymous participants to statements about temporary and perennial rivers, recorded on a Likert scale of 1 to 5 (strong disagreement to strong agreement). Data were collected by survey, in accordance with the human research ethics approvals granted by the ethics committees and review boards at the respective institutions at which the surveys were conducted. Notes defining the abbreviations used are provided within the file

The parliamentary election in Austria, November 2002

Temporary rivers (TRs) are prevalent, biodiverse ecosystems yet often overlooked and underprotected. This may be because inadequate understanding of their ecosystem services leaves them undervalued by society. However, evidence of negative attitudes towards TRs is scant. We investigated the strength and extent of negative attitudes by surveying undergraduate students from Australia, UK, and USA on their agreement (positive attitude) or disagreement (negative attitude) with statements about the ecosystem services, moral consideration, and protection of perennial and TRs. Students were surveyed at the start and end of teaching units covering environmental topics. Disagreement with statements was uncommon (17% across all statements and surveys) and attitudes towards TRs were mostly positive. However, attitudes towards perennial rivers were more positive, particularly in comparison with non‐flowing TRs and with regard to their aesthetic value and recreational amenity. There were no significant differences in attitudes towards perennial and TRs in one teaching unit in Australia, and responses were more often more positive at the end of teaching units in the UK. Our study indicates education can change attitudes. The overall positive response to statements may reflect underlying environmental awareness and pre‐existing interest of participants enrolled in environmental and biology degrees, but not necessarily specific knowledge of TRs. General environmental education across the wider community could improve attitudes towards TRs, particularly when they are not flowing or in regions where they are uncommon or inconspicuous, and could support positive protection measures and innovative, inclusive management

Diverse circular replication-associated protein encoding viruses circulating in invertebrates within a lake ecosystem

International audienceOver the last five years next-generation sequencing has become a cost effective and efficient method for identifying known and unknown microorganisms. Access to this technique has dramatically changed the field of virology, enabling a wide range of environmental viral metagenome studies to be undertaken of organisms and environmental samples from polar to tropical regions. These studies have led to the discovery of hundreds of highly divergent single stranded DNA (ssDNA) virus-like sequences encoding replication-associated proteins. Yet, few studies have explored how viruses might be shared in an ecosystem through feeding relationships. Here we identify 169 circular molecules (160 CRESS DNA molecules, nine circular molecules) recovered from a New Zealand freshwater lake, that we have tentatively classified into 51 putatively novel species and five previously described species (DflaCV-3, -5, -6, -8, -10). The CRESS DNA viruses identified in this study were recovered from molluscs (Echyridella menzeisii, Musculium novaezelandiae, Potamopyrgus antipodarum and Physella acuta) and insect larvae (Procordulia grayi, Xanthocnemis zealandica, and Chironomus zealandicus) collected from Lake Sarah, as well as from the lake water and benthic sediments. Extensive diversity was observed across most CRESS DNA molecules recovered. The putative capsid protein of one viral species was found to be most similar to those of members of the Tombusviridae family, thus expanding the number of known RNA-DNA hybrid viruses in nature. We noted a strong association between the CRESS DNA viruses and circular molecules identified in the water and browser organisms (C. zealandicus, P. antipodarum and P. acuta), and between water sediments and undefended prey species (C. zealandicus). However, we were unable to find any significant correlation of viral assemblages to the potential feeding relationships of the host aquatic invertebrates. (C) 2016 Elsevier B.V. All rights reserved

Aquilegia, Vol. 16 No. 5, September-October 1992: Newsletter of the Colorado Native Plant Society

https://epublications.regis.edu/aquilegia/1064/thumbnail.jp

Edaphic controls on sedge invasion in a tropical wetland assessed with electromagnetic induction

Invasion of sedge in the wetlands of Trinidad is causing an increase in wetland dry season fires and a reduction in coastal pasture, adversely affecting the livelihoods of people living and working in the wetlands. The purpose of our research was to determine if soil properties and water quality could help to explain why the area of sedge is expanding. We conducted an observational study, using geophysical methods and standard sampling techniques to determine the relationship between grass and sedge zonation and soil properties and water quality. Our findings showed that both the electrical conductivity of the soil solution at saturation (ECe) and surface water electrical conductivity (ECw) were significantly higher (P < 0.05) in sedge communities than in grass communities (mean ECe of sedge = 4.4 dS/m; mean ECe grass = 3.7 dS/m; mean ECw of sedge = 0.5 dS/m; mean ECw of grass = 0.2 dS/m). Our interpretation is that changes to the local hydrology by channelizing and levying rivers, reducing wetland flooding, is enhancing saline intrusion and facilitating the invasion of brackish water sedge species into non-salt-tolerant grassland areas