-
Analysing fossil-fuel displacement
-
It is commonly assumed that fossil fuels can be replaced by alternative forms of energy. Now research challenges this assumption, and highlights the role of non-technological solutions to reduce fossil-fuel consumption.
Located in
Resources
/
Climate Science Documents
-
Brownness of organics in aerosols from biomass burning linked to their black carbon content
-
Atmospheric particulate matter plays an important role in the Earth’s radiative balance. Over the past two decades, it has been established that a portion of particulate matter, black carbon, absorbs significant amounts of light and exerts a warming effect rivalling that of anthropogenic carbon dioxide1,2. Most climate models treat black carbon as the sole light-absorbing carbonaceous particulate. However, some organic aerosols, dubbed brown carbon and mainly associated with biomass burning emissions3–6 , also absorbs light7 . Unlike black carbon, whose light absorption properties are well understood8, brown carbon comprises a wide range of poorly characterized compounds that exhibit highly variable absorptivities, with reported values spanning two orders of magnitude3–6,9,10. Here we present smog chamber experiments to characterize the effective absorptivity of organic aerosol from biomass burning under a range of conditions. We show that brown carbon in emissions from biomass burning is associated mostly with organic compounds of extremely low volatility11. In addition, we find that the effective absorptivity of organic aerosol in biomass burning emissions can be parameterized as a function of the ratio of black carbon to organic aerosol, indicating that aerosol absorptivity depends largely on burn conditions, not fuel type. We conclude that brown carbon from biomass burning can be an important factor in aerosol radiative forcing.
Located in
Resources
/
Climate Science Documents
-
Challenges in the conservation, rehabilitation and recovery of native stream salmonid populations: beyond the 2010 Luarca symposium
-
– In May 2010, I chaired a session on challenges to salmonid conservation at the international symposium
‘Advances in the population ecology of stream salmonids’ in Luarca, Spain. I suggested that in addition to scientific challenges, a major challenge will be improving the links between ecologists, conservationists and policy makers. Because the Luarca symposium focused mainly on ecological research, little time was explicitly devoted to conservation. My objective in this paper is to further discuss the role of ecological research in informing salmonid conservation. I begin with a brief overview of research highlights from the symposium. I then use selected examples to show that ecological research has already contributed much towards informing salmonid conservation, but that ecologists will always be faced with limitations in their predictive ability. I suggest that conservation will need to move forward regardless of these limitations, and I call attention to some recent efforts wherein ecological research has played a crucial role. I conclude that ecologists should take urgent action to ensure that their results are availableto inform resource managers, conservation organisations and policy makers regarding past losses and present threats to native, locally-adapted salmonid stocks.
Located in
Resources
/
Climate Science Documents
-
‘As Earth’s testimonies tell’: wilderness conservation in a changing world
-
Too often, wilderness conservation ignores a temporal perspective greater than the past
50 years, yet a long-term perspective (centuries to millennia) reveals the dynamic nature
of many ecosystems. Analysis of fossil pollen, charcoal and stable isotopes, combined
with historical analyses and archaeology can reveal how ongoing interactions between
climatic change, human activities and other disturbances have shaped today’s landscapes
over thousands of years. This interdisciplinary approach can inform wilderness
conservation and also contribute to interpreting current trends and predicting how
ecosystems might respond to future climate change. In this paper, we review literature
that reveals how increasing collaboration among palaeoecologists, archaeologists,
historians, anthropologists and ecologists is improving understanding of ecological
complexity. Drawing on case studies from forested and non-forested ecosystems in
Europe, the Americas, Africa and Australia, we discuss how this integrated approach can
inform wilderness conservation and ecosystem management.
Located in
Resources
/
Climate Science Documents
-
Bird Richness and Abundance in Response to Urban Form in a Latin American City
-
There is mounting evidence that urban areas influence biodiversity. Generalizations how- ever require that multiple urban areas on multiple continents be examined. Here we evaluated the role of urban areas on avian diversity for a South American city, allowing us to examine the effects of urban features common worldwide, using the city of Valdivia, Chile as case study. We assessed the number of birds and their relative abundance in 152 grid cells of equal size (250 m2) distributed across the city. We estimated nine independent variables: land cover diversity (DC), building density (BD), impervious surface (IS),municipal green space (MG),non-municipal green space (NG), domestic garden space (DG), distance to the periphery (DP), social welfare index (SW), and vegetation diversity (RV). Impervious surface represent 41.8% of the study area, while municipal green, non-municipal green and domestic garden represent 11.6%, 23.6% and 16% of the non- man made surface. Exotic vegetation species represent 74.6% of the total species identified across the city. We found 32 bird species, all native with the exception of House Sparrow and Rock Pigeon. The most common species were House Sparrow and Chilean Swallow. Total bird richness responds negatively to IS and MG, while native bird richness responds positively to NG and negatively to BD, IS DG and, RV. Total abundance increase in areas with higher values of DC and BD, and decrease in areas of higher values of IS, SW and VR. Native bird abundance responds positively to NG and negatively to BD, IS MG, DG and RV. Our results suggest that not all the general patterns described in previous studies, conducted mainly in the USA, Europe, and Australia, can be applied to Latin American cities, having important implications for urban planning. Conservation efforts should focus on non-municipal areas, which harbor higher bird diversity, while municipal green areas need to be improved to include elements that can enhance habitat quality for birds and other species. These findings are relevant for urban planning in where both types of green space need to be considered, especially non-municipal green areas, which includes wetlands, today critically threatened by urban development.
Located in
Resources
/
Climate Science Documents
-
The influence of contextual cues on the perceived status of consumption-reducing behavior
-
The question of whether and when behaviors that reduce overall consumption are associated with low status has not been adequately explored. Previous research suggests that some low cost environmentally-friendly behaviors are stigmatized, but has not accounted for the impact of contextual information on perceived status. Here, we use costly signaling theory to describe why consumption-reducing behaviors may be associated with low status and when and how this perception might change. We report two empirical studies in the U.S. that use a large sample of graduate students (N = 447) to examine the effects of contextual information on how consumption-reducing behaviors are perceived. We then explore the perceived appropriateness of consumption-reducing behavior for signaling status relative to alternative non-environmental behaviors. Using linear mixed-effects models, we find that information indicating that consumption-reducing behavior is a choice results in higher perceived status. However, we find that consumption-reducing behaviors are perceived to be less appropriate for conveying status than consumption-intensive behaviors. The environmental orientation of the respondent has little effect on perceptions of status in both studies. These results provide insights into the dynamic, evolutionary process by which sustainable consumption might become more socially acceptable and the social factors that may inhibit this process.
Located in
Resources
/
Climate Science Documents
-
Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios
-
The ocean moderates anthropogenic climate change at the cost of profound alterations of its physics, chemistry, ecology, and services. Here, we evaluate and compare the risks of impacts on marine and coastal ecosystems—and the goods and services they provide—for growing cumulative carbon emissions under two contrasting emissions scenarios. The current emissions trajectory would rapidly and significantly alter many ecosystems and the associated services on which humans heavily depend. A reduced emissions scenario — consistent with the Copenhagen Accord’s goal of a global temperature increase of less than 2°C — is much more favorable to the ocean but still substantially alters important marine ecosystems and associated goods and services. The management options to address ocean impacts narrow as the ocean warms and acidifies.
Located in
Resources
/
Climate Science Documents
-
Stop misuse of biodiversity offsets
-
Governments should not meet existing conservation targets using the compensation that developers pay for damaging biodiversity, say Martine Maron and colleagues.
Located in
Resources
/
Climate Science Documents
-
Formation of soil organic matter via biochemical and physical pathways of litter mass loss
-
Soil organic matter is the largest terrestrial carbon pool (1). The pool size depends on the balance between formation of soil organic matter from decomposition of plant litter and its mineralization to inorganic carbon. Knowledge of soil organic matter formation remains limited (2) and current C numerical models assume that stable soil organic matter is formed primarily from recalcitrant plant litter (3) . However, labile components of plant litter could also form mineral-stabilized soil organic matter (4). Here we followed the decomposition of isotopically labelled above-ground litter and its incorporation into soil organic matter over three years in a grassland in Kansas, USA, and used laboratory incubations to determine the decay rates and pool structure of litter-derived organic matter. Early in decomposition, soil organic matter formed when non-structural compounds were lost from litter. Soil organic matter also formed at the end of decomposition, when both non-structural and structural compounds were lost at similar rates. We conclude that two pathways yield soil organic matter efficiently. A dissolved organic matter–microbial path occurs early in decomposition when litter loses mostly non-structural compounds, which are incorporated into microbial biomass at high rates, resulting in efficient soil organic matter formation. An equally efficient physical-transfer path occurs when litter fragments move into soil.
Located in
Resources
/
Climate Science Documents
-
Experimental studies of dead-wood biodiversity — A review identifying global gaps in knowledge
-
The importance of dead wood for biodiversity is widely recognized but strategies for conservation exist only in some regions worldwide. Most strategies combine knowledge from observational and experimental studies but remain preliminary as many facets of the complex relationships are unstudied. In this first global review of 79 experimental studies addressing biodiversity patterns in dead wood, we identify major knowledge gaps and aim to foster collaboration among researchers by providing a map of previous and ongoing experiments. We show that research has focused primarily on temperate and boreal forests, where results have helped in developing evidence-based conservation strategies, whereas comparatively few such efforts have been made in subtropical or tropical zones. Most studies have been limited to early stages of wood decomposition and many diverse and functionally important saproxylic taxa, e.g., fungi, flies and termites, remain under-represented. Our meta-analysis confirms the benefits of dead-wood addition for biodiversity, particularly for saproxylic taxa, but shows that responses of non-saproxylic taxa are heterogeneous. Our analysis indicates that global conservation of organisms associated with dead wood would benefit most by prioritizing research in the tropics and other neglected regions, focusing on advanced stages of wood decomposition and assessing a wider range of taxa. By using existing experimental set-ups to study advanced decay stages and additional taxa, results could be obtained more quickly and with less effort compared to initiating new experiments.
Located in
Resources
/
Climate Science Documents
