Potsdam Institute for Climate Impact Research

About: Potsdam Institute for Climate Impact Research is a facility organization based out in Potsdam, Germany. It is known for research contribution in the topics: Climate change & Global warming. The organization has 1519 authors who have published 5098 publications receiving 367023 citations.

Climate change responses benefit from a global food system approach

Abstract: A food system framework breaks down entrenched sectoral categories and existing adaptation and mitigation silos, presenting novel ways of assessing and enabling integrated climate change solutions from production to consumption.

Physiology-based phenology models for forest tree species in Germany.

Abstract: Models of phenology are needed for the projection of effects of a changing climate on, for example, forest production, species competition, vegetation-atmosphere feedback and public health. A new phenology model for deciduous tree bud burst is developed and parameters are determined for a wide geographical range (Germany) and several forest tree species. The new model is based on considerations of simple interactions between inhibitory and promotory agents that are assumed to control the developmental status of a plant. Several alternative model structures were formulated emphasizing different hypothetical physiological processes. The new models fitted the observations better than classical models. The bias of the classical models, i.e. overestimation of early observations and underestimation of late observations, could be reduced but not completely removed. Differences in the best-fitting model equations for each species indicated that, for the late spring phases (bud burst of Fagus sylvatica and Quercus robur), the photoperiod played a more dominant role than for early spring phases (bud burst of Betula pendula and Aesculus hippocastanum). Chilling only plays a subordinate role for spring bud burst compared to temperatures preceding this event in our data. The presented modeling approach allowed for a species-specific weighting of the dominant processes. The model results are in accordance with experimental findings that indicate an important role of day length in late spring BB. Potentials for model improvement are discussed.

Resilience of Amazon forests emerges from plant trait diversity

Abstract: Application of a terrestrial biogeochemical model that simulates diverse forest communities suggests that plant trait diversity may enable the Amazon rainforest to adjust to new climate conditions via a process of ecological sorting. Climate change threatens ecosystems worldwide, yet their potential future resilience remains largely unquantified1. In recent years many studies have shown that biodiversity, and in particular functional diversity, can enhance ecosystem resilience by providing a higher response diversity2,3,4,5. So far these insights have been mostly neglected in large-scale projections of ecosystem responses to climate change6. Here we show that plant trait diversity, as a key component of functional diversity, can have a strikingly positive effect on the Amazon forests’ biomass under future climate change. Using a terrestrial biogeochemical model that simulates diverse forest communities on the basis of individual tree growth7, we show that plant trait diversity may enable the Amazon forests to adjust to new climate conditions via a process of ecological sorting, protecting the Amazon’s carbon sink function. Therefore, plant trait diversity, and biodiversity in general, should be considered in large-scale ecosystem projections and be included as an integral part of climate change research and policy.

δ13C of CO2 respired in the dark in relation to δ13C of leaf carbohydrates in Phaseolus vulgaris L. under progressive drought

Abstract: A, leaf net CO2 assimilation a, fractionation against 13C for CO2 diffusion through air b, net fractionation against 13C during CO2 fixation by Rubisco and PEPc δ13C, carbon isotopic composition Δ, discrimination against 13C during CO2 assimilation d, the term including the fractionation due to CO2 dissolution, liquid phase diffusion and also discrimination during both respiration and photorespiration DW, leaf dry weight dδ13C, the difference between CO2 respired in the dark and plant material in their carbon isotope composition dΔ, variation in modelled discrimination at a given pi/pa relative to a reference value at pi/pa = 0·7 FW, leaf fresh weight gc, leaf conductance to CO2 diffusion HPLC, high-performance liquid chromatography LMA, leaf mass per area pa, ambient partial pressure of CO2 pi, intercellular partial pressure of CO2 PEPc, phosphoenolpyruvate carboxylase PPFD, photosynthetic photon flux density RPDB, 13C/12C ratio of standard PDB RS, 13C/12C ratio of sample Rubisco, ribulose 1,5 bisphosphate carboxylase-oxygenase RWC, leaf relative water content SW, leaf saturated weight VPD, vapour pressure deficit The variations in δ13C in both leaf carbohydrates (starch and sucrose) and CO2 respired in the dark from the cotyledonary leaves of Phaseolus vulgaris L. were investigated during a progressive drought. As expected, sucrose and starch became heavier (enriched in 13C) with decreasing stomatal conductance and decreasing pi/pa during the first half (15 d) of the dehydration cycle. Thereafter, when stomata remained closed and leaf net photosynthesis was near zero, the tendency was reversed: the carbohydrates became lighter (depleted in 13C). This may be explained by increased pi/pa but other possible explanations are also discussed. Interestingly, the variations in δ13C of CO2 respired in the dark were correlated with those of sucrose for both well-watered and dehydrated plants. A linear relationship was obtained between δ13C of CO2 respired in the dark and sucrose, respired CO2 always being enriched in 13C compared with sucrose by ≈ 6‰. The whole leaf organic matter was depleted in 13C compared with leaf carbohydrates by at least 1‰. These results suggest that: (i) a discrimination by ≈ 6‰ occurs during dark respiration processes releasing 13C-enriched CO2; and that (ii) this leads to 13C depletion in the remaining leaf material.

Resource nexus perspectives towards the United Nations Sustainable Development Goals

Abstract: Debate around increasing demand for natural resources is often framed in terms of a ‘nexus’, which is perhaps at risk of becoming a buzz word. A nexus between what? Over what scales? And what are the consequences of such a nexus? This article analyses why readers should care about the nexus concept in relation to the United Nations Sustainable Development Goals (SDGs). We discuss a five-nodes definition and propose perspectives that may lead to a reload of climate policy with buy-in from supply-chain managers and resource-rich developing countries. Our research perspectives address modelling approaches and scenarios at the interface of bio-physical inputs and the human dimensions of security and governance.