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Application of a Decision-Making Model to Reduce CO2 Emissions in Iran (Case Study: CHP-CCS technology and renewable energy)
2020
Alinejad, H. R. | Behbahaninia, A. | Mackialeagha, M.
Iran is one of the largest producers of CO2 in the world. Therefore, in order to lessen its greenhouse gas production, thus complying with the Intended Nationally Determined Contributions (INDCs), it should cut its CO2 emissions by about 4% by 2030, compared to 2010. Hence this paper aims at finding an early solution to this problem. Because the country's electricity sector is responsible for the highest annual CO2 emissions, the paper focuses on two technologies that can effectively reduce CO2 emissions from the electricity sector, namely renewable energy and Combined Heat And Power Plants (CHP) with CO2 capture and storage (CCS). Further it assesses adoption of these technologies and their impact on Iran's annual CO2 emission by 2030, considering two main scenarios: the optimistic scenario (OS) which assumes that the policies of the Sixth Development Plan (SDP) will be fully realized as well as the fair scenario (FS) which believes that SDP policies will be followed to some extent by the end of the program. To this end, twenty six micro-factors, affecting CO2 emissions, have been identified and classified into five different groups. The detected micro factors are then introduced to a Gradient Boosting Decision Tree (GBDT) Algorithm to identify the most important specific microscopic factors in Iran. The final detected micro-factors have finally been included in a Gaussian regression model to predict CO2 emissions in Iran by 2030. The findings suggest that if Iran intends to comply with the INDCs, CHP-CCS technology is a solution that has an early return, compared to renewable technologies.
Afficher plus [+] Moins [-]Pb phytostabilization by fast-growing trees inoculated with Pb-resistant plant growth-promoting endophytic bacterium
2020
Yongpisanphop, Jiraporn | Babel, S. | Kruatrachue, M. | Pokethitiyook, P.
Inoculation of endophytic bacteria has been accepted as a promising technique to assist phytostabilization of heavy metal-contaminated soils. This study investigated the effects of inoculating a bacterial strain closely related to Pseudomonas pyschrophila on the plant growth, and phytostabilization of fast-growing trees Acacia mangium and Eucalyptus camaldulensis, growing on artificial spiked soil with Pb up to 1500 mg/kg. After 60 days, the results showed that the strain closely related to P. pyschrophila slightly increased Pb bioavailability and Pb uptake by A. mangium, compared to non-inoculated controls. It slightly reduced Pb bioavailability in soil, but it did not affect the Pb uptake by E. camaldulensis, compared to non-inoculated controls. Interestingly, it was able to significantly increase Pb content in shoots by 3.07-fold in A. mangium and 2.95-fold in E. camaldulensis, compared to non-inoculated controls. Although the inoculation of the strain closely related to P. pyschrophila slightly increased the translocation factor (TF) of Pb in both tree species, their TF values were less than 1. This indicates that plants associated with the strain closely related to P. pyschrophila are suitable for phytostabilization of A. mangium, which may be used for cleaning up Pb contaminated sites. This strain displayed different influences on plant species and was found not suitable for phytostabilization of E. camaldulensis.
Afficher plus [+] Moins [-]Sorption of PAHs to microplastic and their bioavailability and toxicity to marine copepods under co-exposure conditions
2020
Sørensen, Lisbet | Rogers, Emilie | Altin, Dag | Salaberria, Iurgi | Booth, Andy
Organic chemical pollutants associated with microplastic (MP) may represent an alternative exposure route for these chemicals to marine biota. However, the bioavailability of MP-sorbed organic pollutants under conditions where co-exposure occurs from the same compounds dissolved in the water phase has rarely been studied experimentally, especially where pollutant concentrations in the two phases are well characterized. Importantly, higher concentrations of organic pollutants on ingested MP may be less bioavailable to aquatic organisms than the same chemicals present in dissolved form in the surrounding water. In the current study, the sorption kinetics of two model polycyclic aromatic hydrocarbons (PAHs; fluoranthene and phenanthrene) to MP particles in natural seawater at 10 and 20 °C were studied and the bioavailability of MP-sorbed PAHs to marine copepods investigated. Polyethylene (PE) and polystyrene (PS) microbeads with mean diameters ranging from 10-200 µm were used to identify the role of MP polymer type and size on sorption mechanisms. Additionally, temperature dependence of sorption was investigated. Results indicated that adsorption dominated at lower temperatures and for smaller MP (10 µm), while absorption was the prevailing process for larger MP (100 µm). Monolayer sorption dominated at lower PAH concentrations, while multilayer sorption dominated at higher concentrations. PE particles representing ingestible (10 µm) and non-ingestible (100 µm) MP for the marine copepod species Acartia tonsa and Calanus finmarchicus were used to investigate the availability and toxicity of MP-sorbed PAHs. Studies were conducted under co-exposure conditions where the PAHs were also present in the dissolved phase (Cfree), thereby representing more environmentally relevant exposure scenarios. Cfree reduction through MP sorption was reflected in a corresponding reduction of lethality and bioaccumulation, with no difference observed between ingestible and non-ingestible MP. This indicates that only free dissolved PAHs are significantly bioavailable to copepods under co-exposure conditions with MP-sorbed PAHs. | publishedVersion
Afficher plus [+] Moins [-]Measurements of underwater noise radiated by commercial ships at a cabled ocean observatory
2020
Zhang, Guosong | Forland, Tonje Nesse | Johnsen, Espen | Pedersen, Geir | Dong, Hefeng
Measurements of underwater noise radiated under ship normal operations are presented. The acoustic data, from the cabled ocean observatory, are analyzed under each identified ship passage, which was obtained by the Automatic Identification System. Under each passage, sound pressure level is calculated to observe local noise variations due to shipping noise. This paper emphasizes the study of noise variations at the observatory, presents the noise measurements under identified ship passages in the last several years, and provides references for predictive models of underwater noise pollution from commercial ship traffic. From the passages of one ship to the passages of 26 ships, the measurements reveal similar variation patterns when the ships traveled at similar courses, but different patterns when they traveled at different courses. When evaluating the noise variations due to ship traffics, it is important to consider the shipping noise propagation as well as ship movement. | publishedVersion
Afficher plus [+] Moins [-]The 2016 red tide crisis in southern Chile: Possible influence of the mass oceanic dumping of dead salmons
2020
Armijo, Julien | Oerder, Vera | Auger, Pierre-Amaël | Bravo Lizana, Angela | Molina, Ernesto
In 2016, a massive harmful algal bloom (HAB) of Alexandrium catenella around Chiloe island caused one of the major socio-ecological crisis in Chilean history. This red tide occurred in two distinct pulses, the second, most anomalous, bursting with extreme toxicity on the Pacific coast, weeks after the highly controversial dumping off Chiloe of 4,700 t of rotting salmons, killed by a previous HAB of Pseudochattonella verruculosa. We study the transport of this pollution, analyzing the physical oceanographic conditions during and after the dumping. We find that a cyclonic gyre was present between the dumping site and the coast, visible in satellite altimetry and sea surface temperature data. Using Lagrangian simulations, we confirm that near-surface currents could have brought part of the pollution to the coast, and fueled the bloom. This scenario explains also the anomalous later finding of ammonium near Chiloe. Finally we discuss the mismanagement of risk throughout the events. | Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 3150587
Afficher plus [+] Moins [-]First measurement of human exposure to current use pesticides (CUPs) in the atmosphere of central Chile: The case study of Mauco cohort
2020
Cortés, Sandra | Pozo, Karla | Llanos, Yasna | Martínez, Natalia | Foerster, Claudia | Leiva, Cinthya | Ustáriz, Javier | Přibylová, Petra | Klánová, Jana | Jorquera, Héctor
Chile is a leading agricultural producer and thus consumer of insecticides, herbicides, and fungicides. In Molina, Central Chile, a prospective cohort has been established for studying the incidence and risk factors of chronic diseases in the adult population. Our goals were to measure airborne current use pesticides (CUPs), assess their spatial distribution and potential sources, and estimate health risks for the population in Molina. CUPs were measured using passive air samplers (PAS), deployed on six sites from October 2015 to August 2016. Thirty-eight pesticides were analyzed using high performance liquid chromatography (HPLC), but only nine of them were detected. Chlorpyrifos (CPF) was detected with air concentrations ranging from 444 to 14 624 (pg m(-3)). Diazinon, atrazine, dimethoate, metolachlor, simazine, terbuthylazine and tebuconazole were also detected; only pendimethalin had concentrations as high as those of CPF, with a maximum of 14 927 (pg m(-3)). Backward wind trajectories were used to estimate locations of potential sources contributing to airborne CUPs concentrations. Most of the exposure to CUPs was associated with local sources, while regional sources southern/eastern/western of Molina appear to contribute as secondary sources (soil evaporation followed by atmospheric transport) in spring and summer seasons. A health risk assessment using US-EPA's methodology was carried out for inhalation exposure of detected pesticides. None of the measured CUPs were associated with a hazard quotient (HQ) greater than 1, indicating no significant risk due to inhalation of pesticides in Molina's population with the exception of the group of children below 12 years old. However, further investigations are needed to evaluate others CUPs exposure route such as food consumption and dermal exposure to improve our health risk estimations. | Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) 15130011-15110020 180078 1161673 Vicerrectoria de Investigacion, Pontificia Universidad Catolica de Chile 9/2014 RECETOX Research Infrastructure LM2015051 CZ.02.1.01/0.0/0.0/16_013/0001761
Afficher plus [+] Moins [-]Monitoring the occurrence of microplastic ingestion in otariids along the peruvian and chilean coasts
2020
Pérez Venegas, Diego J. | Toro Valdivieso, Constanza | Ayala, Félix | Brito, Beatriz | Iturra, Lunna | Arriagada, Maite | Seguel, Mauricio | Barrios, Carmen | Sepúlveda, Maritza | Oliva, Doris | Cárdenas Alayza, Susana | Urbina, Mauricio A. | Jorquera, Alberto | Castro Nallar, Eduardo | Galbán Malagón, Cristóbal
Repeated reports of microplastic pollution in the marine pinniped diet have emerged in the last years. However, only few studies address the drivers of microplastics presence and the potential implications for monitoring microplastic pollution in the ocean. This study monitored their in the scats (N = 205) of four pinniped species/subspecies at five different locations in the southern Pacific Ocean (Peru and Chile). Samples from all rookeries contained microplastics, and overall, 68% of the examined scats contained fragments/fibers, mostly blue colored. We confirmed that 81.5% of the fragments/fibers were anthropogenic in origin , but only 30% were polymers. Scats from Juan Fernandez Archipelago presented higher microplastic concentrations than continental rookeries. Also, the common diet in each location may influence the levels found in the samples. This study presents a useful non-invasive technique to track plastic pollution in top predator diets as bioindicators for future surveillance/management plans applied to different location. | Rufford Foundation: N 18815-1. Dirección de Investigación y Doctorados, Universidad Andres Bello. Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), CONICYT FONDECYT: 11150548, 116504, 111609059. Instituto Antártico Chileno Grant: INACh RT_12_17. Conicyt PCI: REDI 170292, REDI 170403. Ministerio de Economia, Fomento y Turismo through Iniciativa Científica Milenio (Núcleo Milenio INVASAL). Direccion de Investigación Universidad de Variarais: DIUV 38/2013. Morris Animal Foundation fellowship: N D16ZO-413. Saint Louis Zoo. Chicago Zoological Society. Kansas City Zoo. Woodland Park Zoo.
Afficher plus [+] Moins [-]The effect of long-term use on the Catch efficiency of Biodegradable gillnets
2020
Grimaldo, Eduardo | Herrmann, Bent | Jacques, Nadine | Kubowicz, Stephan | Cerbule, Kristine | Su, Biao | Larsen, Roger B. | Vollstad, Jørgen
The effect of long-term use on the catch efficiency of biodegradable gillnets was investigated during commercial fishing trials and in controlled lab aging tests. The relative catch efficiency between biodegradable and nylon gillnets was evaluated over three consecutive fishing seasons for Atlantic cod (Gadus morhua) in Norway. The biodegradable gillnets progressively lost catch efficiency over time, as they caught 18.4%, 40.2%, and 47.4% fewer fish than the nylon gillnets during the first, second, and third season, respectively. A 1000-hour aging test revealed that both materials began to degrade after just 200 h and that biodegradable gillnets degraded faster than the nylon gillnets. Infrared spectroscopy revealed that the chemical structure of the biodegradable polymer changed more than the nylon. Although less catch efficient than nylon gillnets, biodegradable gillnets have great potential for reducing both capture in lost fishing gear and plastic pollution at sea, which are major problems in fisheries worldwide. | publishedVersion
Afficher plus [+] Moins [-]Cadmium distribution in mature durum wheat grains using dissection, laser ablation-ICP-MS and synchrotron techniques *
2020
Yan, Bofang | Isaure, Marie-Pierre | Mounicou, Sandra | Castillo-Michel, Hiram | De Nolf, Wout | Nguyen, Christophe | Cornu, Jean-Yves
Understanding how essential and toxic elements are distributed in cereal grains is a key to improving the nutritional quality of cereal-based products. The main objective of this work was to characterize the distribution of Cd and of nutrients (notably Cu, Fe, Mn, P, S and Zn) in the durum wheat grain. Laser ablation inductively coupled mass spectrometry and synchrotron micro X-ray fluorescence were used for micro-scale mapping of Cd and nutrients. A dissection approach was used to quantitatively assess the distribution of Cd and nutrients among grain tissues. Micro X-ray absorption near-edge spectroscopy was used to identify the Cd chemical environment in the crease. Cadmium distribution was characterized by strong accumulation in the crease and by non-negligible dissemination in the endosperm. Inside the crease, Cd accumulated most in the pigment strand where it was mainly associated with sulfur ligands. High-resolution maps highlighted very specific accumulation areas of some nutrients in the germ, for instance Mo in the root cortex primordia and Cu in the scutellum. Cadmium loading into the grain appears to be highly restricted. In the grain, Cd co-localized with several nutrients, notably Mn and Zn, which challenges the idea of selectively removing Cd-enriched fractions by dedicated milling process.
Afficher plus [+] Moins [-]Microplastic dispersal behavior in a novel overhead stirring aqueous exposure system
2020
Salaberria, Iurgi | Nadvornik-Vincent, Colette | Monticelli, Giovanna | Altin, Dag | Booth, Andy
Using nominal dose metrics to describe exposure conditions in laboratory-based microplastic uptake and effects studies may not adequately represent the true exposure to the organisms in the test system, making data interpretation challenging. In the current study, a novel overhead stirring method using flocculators was assessed for maintaining polystyrene (PS) microbeads (Ø10.4 μm; 1.05 g cm−3) in suspension in seawater during 24 h and then compared with static and rotational exposure setups. Under optimized conditions, the system was able to maintain 59% of the initial PS microbeads in suspension after 24 h, compared to 6% using a static system and 100% using a rotating plankton wheel. Our findings document for the first time that overhead stirring as well as other, commonly used exposure systems (static) are unable to maintain constant microplastic exposure conditions in laboratory setups whereas rotation is very effective. This suggests toxicological studies employing either static or overhead stirring systems may be greatly overestimating the true microplastic exposure conditions. | publishedVersion
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