Global Environmental Scenarios Research Articles

Between continuous presents and disruptive futures: Identifying the ideological backbones of global environmental scenarios

Despite the great relevance of global environmental scenarios for the study of environmental change and sustainability transitions, they have rarely been the object of analysis for scholars of the social sciences. In this article, we analyze the ideological assumptions of 993 global environmental scenarios contained in 243 academic works. By developing a new categorization of environmental scenarios, we investigate the economic and governance organization reflected in the scenarios, as well as the portrayed human-nature relationships. We find that global environmental scenarios developed and used by the scientific community largely reproduce rather than break with dominant power structures in the economic, governance and cultural domain. The majority of scenarios reflects an anthropocentric worldview and assumes that the logic of global capitalism and of the Westphalian state-based governance system will not change radically during the 21st century. The implicit solution of sustainability problems dominating these scenarios is a combination of continuous economic growth, rapid technological progress and an international (environmental) agreement. ‘Alternative scenarios’ are scarce, often only problematize one dimension of the social structure of world society and frequently lack explicit drivers of change or pathways to desirable futures. To increase the diversity of scenarios, future research should focus on refining and quantifying existing post-capitalist, post-state-centric and/or ecocentric scenarios, and on developing a range of scenarios whose storyline systematically problematize or even break with current power structures.

Seeds of good anthropocenes: developing sustainability scenarios for Northern Europe

Scenario development helps people think about a broad variety of possible futures; however, the global environmental change community has thus far developed few positive scenarios for the future of the planet and humanity. Those that have been developed tend to focus on the role of a few common, large-scale external drivers, such as technology or environmental policy, even though pathways of positive change are often driven by surprising or bottom-up initiatives that most scenarios assume are unchanging. We describe an approach, pioneered in Southern Africa and tested here in a new context in Northern Europe, to developing scenarios using existing bottom-up transformative initiatives to examine plausible transitions towards positive, sustainable futures. By starting from existing, but marginal initiatives, as well as current trends, we were able to identify system characteristics that may play a key role in sustainability transitions (e.g., gender issues, inequity, governance, behavioral change) that are currently under-explored in global environmental scenarios. We suggest that this approach could be applied in other places to experiment further with the methodology and its potential applications, and to explore what transitions to desirables futures might be like in different places.

Elevated CO2 affects secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils

Secondary metabolites play important roles in plant interactions with the environment. The co-occurrence of heavy metal contamination of soils and rising atmospheric CO2 has important effects on plant. It is important to explore the ways in which production of plant secondary metabolites is affected by heavy metals under elevated atmospheric CO2. We examined the effects of elevated CO2 on secondary metabolite contents in Robinia pseudoacacia seedlings grown in Cd- and lead (Pb)-contaminated soils. The increase in secondary metabolites was greater under Cd + Pb exposure than under exposure to individual metals regardless of elevated CO2 with the exception of condensed tannins in leaves and total alkaloids in stems. Except for phenolic compounds and condensed tannins, elevated CO2 was associated with increased secondary metabolite contents in leaves and stems of plants exposed to Cd, Pb, and Cd + Pb compared to plants exposed to ambient CO2 + metals. Changes in saponins in leaves and alkaloids in stems were greater than changes in the other secondary metabolites. Significant interactive effects of CO2, Cd, and Pb on secondary metabolites were observed. Saponins in leaves and alkaloids in stems were more sensitive than other secondary metabolites to elevated CO2 + Cd + Pb. Elevated CO2 could modulate plant protection and defense mechanisms in R. pseudoacacia seedlings exposed to heavy metals by altering the production of secondary metabolites. The increased Cd and Pb uptake under elevated CO2 suggested that R. pseudoacacia may be used in the phytoremediation of heavy metal-contaminated soils under global environmental scenarios.

Overexpression of bacterial mtlD gene in peanut improves drought tolerance through accumulation of mannitol.

In the changing global environmental scenarios, water scarcity and recurrent drought impose huge reductions to the peanut (Arachis hypogaea L.) crop yield. In plants, osmotic adjustments associated with efficient free radical scavenging ability during abiotic stress are important components of stress tolerance mechanisms. Mannitol, a compatible solute, is known to scavenge hydroxyl radicals generated during various abiotic stresses, thereby conferring tolerance to water-deficit stress in many plant species. However, peanut plant is not known to synthesize mannitol. Therefore, bacterial mtlD gene coding for mannitol 1-phosphate dehydrogenase under the control of constitutive promoter CaMV35S was introduced and overexpressed in the peanut cv. GG 20 using Agrobacterium tumefaciens-mediated transformation. A total of eight independent transgenic events were confirmed at molecular level by PCR, Southern blotting, and RT-PCR. Transgenic lines had increased amount of mannitol and exhibited enhanced tolerance in response to water-deficit stress. Improved performance of the mtlD transgenics was indicated by excised-leaf water loss assay and relative water content under water-deficit stress. Better performance of transgenics was due to the ability of the plants to synthesize mannitol. However, regulation of mtlD gene expression in transgenic plants remains to be elucidated.

Modelling suitable areas for Hyla meridionalis under current and future hypothetical expansion scenarios

AbstractNew records of the frog Hyla meridionalis have been reported on the Iberian Central mountain range, although it is not clear if those records correspond to an expansion process or to a lack of sampling. The species' global distribution was modelled to identify possible areas of expansion in the current environment and in a near future environment. To verify the effects of modelling a dynamic situation, the hypothetical expansion process from south to north was simulated in the current scenario. The species records were partitioned in four different datasets and modelled iteratively over a study area enclosing all records: records only from North Africa, from North Africa and South Iberian Peninsula, from North Africa and all the Iberian Peninsula, and from the entire distribution. The complete dataset was also used to extrapolate the model to a current and future global environmental scenarios. The models were compared by subtraction per pairs and by Cohen's Kappa. No spatio-temporal trends were detected in species records; therefore, the hypothesis of a recent expansion is nor supported. The species spread only to the Mediterranean part of the Iberian Peninsula when modelling only with African records, and to Europe when modelling also with Iberian records. The extrapolation models were moderately similar: large suitable areas were predicted in all the continents. Temperature variables contributed more to models. The species can expand to new suitable areas, although it is not possible to know if it would expand outside the biogeographical regions where the species is present.

Where next with global environmental scenarios?

This article was submitted without an abstract, please refer to the full-text PDF file.

Where next with global environmental scenarios?

Where next with global environmental scenarios?

Why global scenarios need ecology

Human well-being depends on ecosystem services such as food and clean water. Yet ecosystems and the services they provide are changing, often in ways we cannot anticipate. How can we cope with surprises and uncertainties when we cannot predict them? One approach is to make decisions that are robust to a number of different futures. Those interested in global environmental issues have used scenarios – sets of stories about the future – to help discuss those issues and to identify policy alternatives. To date, most global environmental scenarios have treated ecological dynamics as the product of large-scale anthropogenic drivers and have not considered ecological feedbacks to these drivers. Global scenarios could benefit from the input of ecologists, as this would lead to the incorporation of more realistic ecosystem dynamics. Similarly, ecology could benefit from involvement in scenario planning. Unlike many technical models, scenarios, easily understood as stories, can be used for communication and outreach, to build public appreciation of ecological science and the ecological dilemmas we face.