| 1. |
- Blume-Werry, Gesche, 1985-, et al.
(författare)
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Arctic rooting depth distribution influences modelled carbon emissions but cannot be inferred from aboveground vegetation type
- 2023
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Ingår i: New Phytologist. - : John Wiley & Sons. - 0028-646X .- 1469-8137. ; 240:2, s. 502-514
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Tidskriftsartikel (refereegranskat)abstract
- The distribution of roots throughout the soil drives depth-dependent plant–soil interactions and ecosystem processes, particularly in arctic tundra where plant biomass, is predominantly belowground. Vegetation is usually classified from aboveground, but it is unclear whether such classifications are suitable to estimate belowground attributes and their consequences, such as rooting depth distribution and its influence on carbon cycling. We performed a meta-analysis of 55 published arctic rooting depth profiles, testing for differences both between distributions based on aboveground vegetation types (Graminoid, Wetland, Erect-shrub, and Prostrate-shrub tundra) and between ‘Root Profile Types’ for which we defined three representative and contrasting clusters. We further analyzed potential impacts of these different rooting depth distributions on rhizosphere priming-induced carbon losses from tundra soils. Rooting depth distribution hardly differed between aboveground vegetation types but varied between Root Profile Types. Accordingly, modelled priming-induced carbon emissions were similar between aboveground vegetation types when they were applied to the entire tundra, but ranged from 7.2 to 17.6 Pg C cumulative emissions until 2100 between individual Root Profile Types. Variations in rooting depth distribution are important for the circumpolar tundra carbon-climate feedback but can currently not be inferred adequately from aboveground vegetation type classifications.
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| 2. |
- Chrysafi, Anna, et al.
(författare)
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Quantifying Earth system interactions for sustainable food production via expert elicitation
- 2022
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 5:10, s. 830-842
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Tidskriftsartikel (refereegranskat)abstract
- Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production.
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| 3. |
- Fader, Marianela, et al.
(författare)
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Past and present biophysical redundancy of countries as a buffer to changes in food supply
- 2016
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Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 11:5
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Tidskriftsartikel (refereegranskat)abstract
- Spatially diverse trends in population growth, climate change, industrialization, urbanization and economic development are expected to change future food supply and demand. These changes may affect the suitability of land for food production, implying elevated risks especially for resource-constrained, food-importing countries. We present the evolution of biophysical redundancy for agricultural production at country level, from 1992 to 2012. Biophysical redundancy, defined as unused biotic and abiotic environmental resources, is represented by the potential food production of 'spare land', available water resources (i.e., not already used for human activities), as well as production increases through yield gap closure on cultivated areas and potential agricultural areas. In 2012, the biophysical redundancy of 75 (48) countries, mainly in North Africa, Western Europe, the Middle East and Asia, was insufficient to produce the caloric nutritional needs for at least 50% (25%) of their population during a year. Biophysical redundancy has decreased in the last two decades in 102 out of 155 countries, 11 of these went from high to limited redundancy, and nine of these from limited to very low redundancy. Although the variability of the drivers of change across different countries is high, improvements in yield and population growth have a clear impact on the decreases of redundancy towards the very low redundancy category. We took a more detailed look at countries classified as 'Low Income Economies (LIEs)' since they are particularly vulnerable to domestic or external food supply changes, due to their limited capacity to offset for food supply decreases with higher purchasing power on the international market. Currently, nine LIEs have limited or very low biophysical redundancy. Many of these showed a decrease in redundancy over the last two decades, which is not always linked with improvements in per capita food availability.
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| 4. |
- Gerten, Dieter, et al.
(författare)
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Feeding ten billion people is possible within four terrestrial planetary boundaries
- 2020
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 3:3, s. 200-208
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Tidskriftsartikel (refereegranskat)abstract
- Global agriculture puts heavy pressure on planetary boundaries, posing the challenge to achieve future food security without compromising Earth system resilience. On the basis of process-detailed, spatially explicit representation of four interlinked planetary boundaries (biosphere integrity, land-system change, freshwater use, nitrogen flows) and agricultural systems in an internally consistent model framework, we here show that almost half of current global food production depends on planetary boundary transgressions. Hotspot regions, mainly in Asia, even face simultaneous transgression of multiple underlying local boundaries. If these boundaries were strictly respected, the present food system could provide a balanced diet (2,355 kcal per capita per day) for 3.4 billion people only. However, as we also demonstrate, transformation towards more sustainable production and consumption patterns could support 10.2 billion people within the planetary boundaries analysed. Key prerequisites are spatially redistributed cropland, improved water-nutrient management, food waste reduction and dietary changes. Agriculture transforms the Earth and risks crossing thresholds for a healthy planet. This study finds almost half of current food production crosses such boundaries, as for freshwater use, but that transformation towards more sustainable production and consumption could support 10.2 billion people.
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| 5. |
- Gleeson, Tom, et al.
(författare)
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Illuminating water cycle modifications and Earth system resilience in the Anthropocene
- 2020
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Ingår i: Water resources research. - 0043-1397 .- 1944-7973. ; 56:4
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Tidskriftsartikel (refereegranskat)abstract
- Fresh water—the bloodstream of the biosphere—is at the center of the planetary drama of the Anthropocene. Water fluxes and stores regulate the Earth's climate and are essential for thriving aquatic and terrestrial ecosystems, as well as water, food, and energy security. But the water cycle is also being modified by humans at an unprecedented scale and rate. A holistic understanding of freshwater's role for Earth system resilience and the detection and monitoring of anthropogenic water cycle modifications across scales is urgent, yet existing methods and frameworks are not well suited for this. In this paper we highlight four core Earth system functions of water (hydroclimatic regulation, hydroecological regulation, storage, and transport) and key related processes. Building on systems and resilience theory, we review the evidence of regional‐scale regime shifts and disruptions of the Earth system functions of water. We then propose a framework for detecting, monitoring, and establishing safe limits to water cycle modifications and identify four possible spatially explicit methods for their quantification. In sum, this paper presents an ambitious scientific and policy grand challenge that could substantially improve our understanding of the role of water in the Earth system and cross‐scale management of water cycle modifications that would be a complementary approach to existing water management tools.
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| 6. |
- Guillaume, Joseph H. A., et al.
(författare)
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Giving Legs to Handprint Thinking : Foundations for Evaluating the Good We Do
- 2020
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Ingår i: Earth's Future. - 2328-4277. ; 8:6
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Tidskriftsartikel (refereegranskat)abstract
- In environmental management and sustainability there is an increasing interest in measurement and accounting of beneficial impact-as an incentive to action, as a communication tool, and to move toward a positive, constructive approach focused on opportunities rather than problems. One approach uses the metaphor of a handprint, complementing the notion of environmental footprints, which have been widely adopted for impact measurement and accounting. We analyze this idea by establishing core principles of handprint thinking: Handprint encourages actions with positive impacts and connects to analyses of footprint reductions but adds value to them and addresses the issue of what action should be taken. We also identify five key questions that need to be addressed and decisions that need to be made in performing a (potentially quantitative) handprint assessment, related to scoping of the improvement to be made, how it is achieved, and how credit is assigned, taking into account constraints on action. A case study of the potential water footprint reduction of an average Finn demonstrates how handprint thinking can be a natural extension of footprint reduction analyses. We find that there is a diversity of possible handprint assessments that have the potential to encourage doing good. Their common foundation is handprint thinking.
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| 7. |
- Heslin, Alison, et al.
(författare)
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Simulating the Cascading Effects of an Extreme Agricultural Production Shock : Global Implications of a Contemporary US Dust Bowl Event
- 2020
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Ingår i: Frontiers in Sustainable Food Systems. - : Frontiers Media SA. - 2571-581X. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Higher temperatures expected by midcentury increase the risk of shocks to crop production, while the interconnected nature of the current global food system functions to spread the impact of localized production shocks throughout the world. In this study, we analyze the global potential impact of a present-day event of equivalent magnitude to the US Dust Bowl, modeling the ways in which a sudden decline in US wheat production could cascade through the global network of agricultural trade. We use observations of country-level production, reserves, and trade data in a Food Shock Cascade model to explore trade adjustments and country-level inventory changes in response to a major, multiyear production decline. We find that a 4-year decline in wheat production of the same proportional magnitude as occurred during the Dust Bowl greatly reduces both wheat supply and reserves in the United States and propagates through the global trade network. By year 4 of the event, US wheat exports fall from 90.5 trillion kcal before the drought to 48 trillion to 52 trillion kcal, and the United States exhausts 94% of its reserves. As a result of reduced US exports, other countries meet their needs by leveraging their own reserves, leading to a 31% decline in wheat reserves globally. These findings demonstrate that an extreme production decline would lead to substantial supply shortfalls in both the United States and in other countries, where impacts outside the United States strongly depend on a country's reserves and on its relative position in the global trade network.
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| 8. |
- Kummu, Matti, et al.
(författare)
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Interplay of trade and food system resilience : Gains on supply diversity over time at the cost of trade independency
- 2020
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Ingår i: Global food security. - : Elsevier BV. - 2211-9124. ; 24
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Tidskriftsartikel (refereegranskat)abstract
- Rapidly increasing international food trade has drastically altered the global food system over the past decades. Using national scale indicators, we assess two of the resilience principles that directly reflect the effects of global trade on food systems - namely, maintaining diversity and redundancy, and managing connectivity. We perform our analysis for four nutritional components: dietary energy, proteins, fat, and quantity of vegetables & fruits the key pillars of the WHO dietary recommendations. Our results indicate that, between 1987 and 2013, food supply diversity increased significantly for most of the world's population at the cost of an elevated dependency upon food imports. Food production diversity, particularly in terms of dietary energy and vegetables & fruits, increased for a large proportion of the world population, with the exception being major exporting countries, where it decreased. Of particular note is our finding that, despite a growing number of people being heavily dependent upon imports, the number of import partners decreased more often than it increased, except for the case of vegetables & fruits. This combination of increased dependency on imports and a reduced number of import partners indicates a potential vulnerability to disruptions in linked food systems. Additionally, it is alarming that we found many countries where the studied resilience aspects systematically declined, elevating their exposure to future shocks in the food system.
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| 9. |
- Marchand, Philippe, et al.
(författare)
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Reserves and trade jointly determine exposure to food supply shocks
- 2016
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Ingår i: Environmental Research Letters. - : Institute of Physics Publishing (IOPP). - 1748-9326. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- While a growing proportion of global food consumption is obtained through international trade, there is an ongoing debate on whether this increased reliance on trade benefits or hinders food security, and specifically, the ability of global food systems to absorb shocks due to local or regional losses of production. This paper introduces a model that simulates the short-term response to a food supply shock originating in a single country, which is partly absorbed through decreases in domestic reserves and consumption, and partly transmitted through the adjustment of trade flows. By applying the model to publicly-available data for the cereals commodity group over a 17 year period, we find that differential outcomes of supply shocks simulated through this time period are driven not only by the intensification of trade, but as importantly by changes in the distribution of reserves. Our analysis also identifies countries where trade dependency may accentuate the risk of food shortages from foreign production shocks; such risk could be reduced by increasing domestic reserves or importing food from a diversity of suppliers that possess their own reserves. This simulation-based model provides a framework to study the short-term, nonlinear and out-of-equilibrium response of trade networks to supply shocks, and could be applied to specific scenarios of environmental or economic perturbations.
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| 10. |
- Mohan, Chinchu, et al.
(författare)
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Poor correlation between large-scale environmental flow violations and freshwater biodiversity : implications for water resource management and the freshwater planetary boundary
- 2022
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Ingår i: Hydrology and Earth System Sciences. - : Copernicus GmbH. - 1027-5606 .- 1607-7938. ; 26:23, s. 6247-6262
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Tidskriftsartikel (refereegranskat)abstract
- The freshwater ecosystems around the world are degrading, such that maintaining environmental flow (EF) in river networks is critical to their preservation. The relationship between streamflow alterations (subsequent EF violations2) and the freshwater biodiversity response is well established at the scale of stream reaches or small basins (~< 100 km2). However, it is unclear if this relationship is robust at larger scales, even though there are large-scale initiatives to legalize the EF requirement. Moreover, EFs have been used in assessing a planetary boundary for freshwater. Therefore, this study intends to conduct an exploratory evaluation of the relationship between EF violation and freshwater biodiversity at globally aggregated scales and for freshwater ecoregions. Four EF violation indices (severity, frequency, probability of shifting to a violated state, and probability of staying violated) and seven independent freshwater biodiversity indicators (calculated from observed biota data) were used for correlation analysis. No statistically significant negative relationship between EF violation and freshwater biodiversity was found at global or ecoregion scales. These findings imply the need for a holistic bio-geo-hydro-physical approach in determining the environmental flows. While our results thus suggest that streamflow and EF may not be the only determinant of freshwater biodiversity at large scales, they do not preclude the existence of relationships at smaller scales or with more holistic EF methods (e.g., including water temperature, water quality, intermittency, connectivity, etc.) or with other biodiversity data or metrics
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