Effects of imidacloprid on the ecology of sub-tropical freshwater microcosms
Sumon, Kizar Ahmed ; Ritika, Afifat Khanam ; Peeters, Edwin T.H.M. ; Rashid, Harunur ; Bosma, Roel H. ; Rahman, Md Shahidur ; Fatema, Mst Kaniz ; Brink, Paul J. Van den - \ 2018
Environmental Pollution 236 (2018). - ISSN 0269-7491 - p. 432 - 441.
Bangladesh - Freshwater ecosystem - Insecticide - Neonicotinoid
The neonicotinoid insecticide imidacloprid is used in Bangladesh for a variety of crop protection purposes. Imidacloprid may contaminate aquatic ecosystems via spray drift, surface runoff and ground water leaching. The present study aimed at assessing the fate and effects of imidacloprid on structural (phytoplankton, zooplankton, macroinvertebrates and periphyton) and functional (organic matter decomposition) endpoints of freshwater, sub-tropical ecosystems in Bangladesh. Imidacloprid was applied weekly to 16 freshwater microcosms (PVC tanks containing 400 L de-chlorinated tap water) at nominal concentrations of 0, 30, 300, 3000 ng/L over a period of 4 weeks. Results indicated that imidacloprid concentrations from the microcosm water column declined rapidly. Univariate and multivariate analysis showed significant effects of imidacloprid on the zooplankton and macroinvertebrate community, some individual phytoplankton taxa, and water quality variables (i.e. DO, alkalinity, ammonia and nitrate), with Cloeon sp., Diaptomus sp. and Keratella sp. being the most affected species, i.e. showing lower abundance values in all treatments compared to the control. The observed high sensitivity of Cloeon sp. and Diaptomus sp. was confirmed by the results of single species tests. No significant effects were observed on the species composition of the phytoplankton, periphyton biomass and organic matter decomposition for any of the sampling days. Our study indicates that (sub-)tropical aquatic ecosystems can be much more sensitive to imidacloprid compared to temperate ones.
The Paris Agreement: resolving the inconsistency between global goals and national contributions
Höhne, Niklas ; Kuramochi, Takeshi ; Warnecke, Carsten ; Röser, Frauke ; Fekete, Hanna ; Hagemann, Markus ; Day, Thomas ; Tewari, Ritika ; Kurdziel, Marie ; Sterl, Sebastian ; Gonzales, Sofia - \ 2017
Climate Policy 17 (2017)1. - ISSN 1469-3062 - p. 16 - 32.
The adoption of the Paris Agreement in December 2015 moved the world a step closer to avoiding dangerous climate change. The aggregated individual intended nationally determined contributions (INDCs) are not yet sufficient to be consistent with the long-term goals of the agreement of ‘holding the increase in global average temperature to well below 2°C’ and ‘pursuing efforts’ towards 1.5°C. However, the Paris Agreement gives hope that this inconsistency can be resolved. We find that many of the contributions are conservative and in some cases may be overachieved. We also find that the preparation of the INDCs has advanced national climate policy-making, notably in developing countries. Moreover, provisions in the Paris Agreement require countries to regularly review, update and strengthen these actions. In addition, the significant number of non-state actions launched in recent years is not yet adequately captured in the INDCs. Finally, we discuss decarbonization, which has happened faster in some sectors than expected, giving hope that such a transition can also be accomplished in other sectors. Taken together, there is reason to be optimistic that eventually national action to reduce emissions will be more consistent with the agreed global temperature limits.