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Este libro de acceso abierto proporciona una perspectiva multidisciplinaria sobre el potencial de los árboles para mitigar los impactos negativos del cambio climático en la producción de cacao Ce livre en libre accès offre une perspective multidisciplinaire sur le potentiel des arbres pour atténuer les impacts négatifs du changement climatique sur la production de cacao This open access book provides multidisciplinary perspective on the potential of trees to mitigate negative impacts of climate change on cocoa production يوفر هذا الكتاب المفتوح منظورًا متعدد التخصصات حول إمكانات الأشجار للتخفيف من الآثار السلبية لتغير المناخ على إنتاج الكاكاو

The aim of this study is to identify non-technological critical success factors (CSFs) that influence the different phases of the project life cycle for the deployment of centralized biogas projects; as there is a knowledge gap in this area. This was performed by applying a longitudinal process analysis approach and an analytical framework based on findings from previous studies. Data were collected through extensive document collection and analysis, combined with in-depth semi-structured interviews. The study resulted in the identification of a total of 30 non-technological critical success factors in the case of Solrød Biogas. These were subsequently linked to one of the different phases of the project lifecycle (conceptualization phase, planning phase, execution phase) or categorized as general CSFs. We hope that the findings in this study can help ensure better management of biogas projects and enhance the capabilities of governmental bodies in supporting projects in the future, so a higher rate of centralized biogas projects is successfully implemented both in Denmark and other countries

Abstract Thermal stability experiments were performed at 100 °C of the dye-sensitized solar cell ruthenium dye N719. The experiments were performed as simple test-tube experiments carried out with colloidal solutions of N719-loaded TiO2 particles. The dye degradation was followed by the use of HPLC-coupled electrospray mass spectrometry. The longest half life of N719 of 84 h at 100 °C was obtained in 3-methoxypropionitrile based electrolytes containing 0.5 M 4-TBP, no Li+ ions and 0.25 M I 3 - . If 4-TBP was removed from the solution the degradation rate of N719 increased up to 3–15 times depending on the I 3 - concentration. If Li+ ions were added to the electrolyte the degradation increased by a factor of 4–16 times and the thermal degradation product mixture became more complex. It is suggested that an adsorbed layer of 4-TBP on the TiO2 protects the N719 dye against solvent substitution and oxidation processes. A complexation constant of Li+ ions with 4-TBP equal to 9 M−1 was obtained by 13C NMR. The Li+ complexation with 4-TBP is thought to destroy the adsorbed protection layer of 4-TBP on the TiO2 surface. It is concluded that addition of 4-TBP or other N-additives to the DSC electrolyte is important to enhance the dye life time at elevated temperatures. However, addition of Li+ to the electrolyte should be avoided if the wish is to construct DSCs with high thermal stability.

Abstract The kinetics of the thiocyanate substitution of the solar cell sensitizer [Ru(Hdcbpy)2(NCS)2]2−, 2(n-C4H9)4N+ (H2dcbpy=L=2,2′-bipyridine-4,4′-dicarboxylic acid), known as N719, by acetonitrile, 3-methoxypropionitrile, and 4-tert-butylpyridine (4-TBP) have been determined in both homogenous solutions and colloidal mixtures of N719-dyed TiO2 nanocrystalline particles. Thiocyanate ligand substitution by the solvents (S) acetonitrile or 3-methoxypropionitrile in homogeneous solutions occurs at elevated temperatures (80–110 °C) by means of a simple slow pseudo-first-order reaction leading to the formation of the product [RuL2(NCS)(S)]+ with a half-life time t1/2 ∼2000 h of N719 at 80 °C. If tert-butylpyridine (0.5 M) is added, the end product instead becomes [RuL2(NCS)(4-TBP)]+ with a t1/2 ∼1000 h. When N719 is bound to TiO2 particles, the reactions with S and 4-TBP give the same products as occur in the homogenous solutions; however, the reactions are approximately 10 times faster. For the reaction of a colloidal mixture of N719-dyed TiO2 particles in acetonitrile containing 0.5 M 4-TBP, a t1/2(het) of 120 h was calculated at 85 °C. The N719-based DSSC cells with acetonitrile and 4-TBP as solvent and additive are therefore not expected to be able to pass a 1000-h thermal stress test in the dark at 85 °C due to thermal degradation of the N719 dye. Adding guanidine thiocyanate to the colloidal solutions, however, decreased the rate of [RuL2(NCS)(4-TBP)]+ formation by a factor of 2–10; it thus may be used as an additive to prevent the thermal degradation of thiocyanate-based ruthenium complexes in DSSC solar cells.

The tropicalization of temperate marine ecosystems can lead to increased herbivory rates, reducing the standing stock of seaweeds and potentially causing increases in detritus production. However, long-term studies analysing these processes associated with the persistence of tropical herbivores in temperate reefs are lacking. We assessed the seasonal variation in abundances, macrophyte consumption, feeding modes and defecation rates of the range-extending tropical rabbitfishSiganus fuscescensand the temperate silver drummerKyphosus sydneyanusand herring caleOlisthops cyanomelason tropicalized reefs of Western Australia. Rabbitfish overwintered in temperate reefs, consumed more kelp and other macrophytes in all feeding modes, and defecated more during both summer and winter than the temperate herbivores. Herbivory and defecation increased with rabbitfish abundance, but this was dependent on temperature, with higher rates attained by big schools during summer and lower rates in winter. Still, rabbitfish surpassed temperate herbivores, leading to a fivefold acceleration in the transformation of macrophyte standing stock to detritus, a function usually attributed to sea urchins in kelp forests. Our results suggest that further warming and tropicalization will not only increase primary consumption and affect the habitat structure of temperate reefs but also increase detritus production, with the potential to modify energy pathways.

Abstract This study evaluates the potential to produce phosphorus (P)-rich fertilizer substrates with high plant availability as well as carbon (C)-rich biochar with soil enhancement properties in a single slow-pyrolysis plant. Campaign-based production or co-production of soil enhancers and fertilizer substrates may increase the potential societal value of slow pyrolysis plants. The assessment focus on conventional slow pyrolysis operated at 600 °C to produce biochar from various substrates as well as two options for post-process char treatments—char oxidation at 550 °C and char steam gasification at 800 °C, as a potential way to improve substrate fertilizer value. Four P-rich biomass residues including municipal sewage sludge (SS), biogas fiber (BF), cattle manure (CM), and poultry manure (PM) as well as two C-rich biomasses: wood chips (WC) and wheat straw (WS), were tested. Production yields of biochar and ash from char oxidation and steam gasification were compared and the materials were characterized to be used as soil enhancers and P-fertilizers through direct analysis and soil incubation studies with two different agricultural soils. All thermal treatments increased the concentration of the plant nutrients P, potassium and magnesium in the resulting biochar and ashes compared to the dry biomass. At the same time, concentrations of nitrogen and sulfur were reduced. The dry biomasses generally increased the amount of available P in the soils to a greater extent than biochar or ashes at an application rate of 80 mg P/kg soil. The P-rich biochar and ash made from BF, CM and PM had higher P fertilizer values than those made from SS. In terms of thermal processes, pyrolysis with subsequent char steam gasification was found to be the best option for high P availability in both soils, except for operation on SS where the oxidized char gave the best results. The C-rich biochars made from wood and wheat straw both showed potential for improving soil properties including soil organic matter (SOM) content, cation exchange capacity (CEC) and water holding capacity (WHC). The study shows that campaign operation of slow pyrolysis with the option for char steam gasification is a viable option for producing fertilizer substrates with high levels of plant available P as well as biochar with substantial soil enhancing properties on a single plant. In addition, results also indicate that direct co-pyrolysis of P-rich substrates—especially BF and CM, with any of the two tested C-rich substrates—without subsequent char treatment may be a sufficiently well integrated option for combined soil fertility and soil P fertilization management. Graphic Abstract

AbstractTropical marine ecosystems are highly vulnerable to pollution and climate change. It is relatively unknown how tropical species may develop an increased tolerance to these stressors and the cost of adaptations. We addressed these issues by exposing a keystone tropical marine copepod, Pseudodiaptomus annandalei, to copper (Cu) for 7 generations (F1–F7) during three treatments: control, Cu and pCu (the recovery treatment). In F7, we tested the “contaminant-induced climate change sensitivity” hypothesis (TICS) by exposing copepods to Cu and extreme temperature. We tracked fitness and productivity of all generations. In F1, Cu did not affect survival and grazing but decreased nauplii production. In F2-F4, male survival, grazing, and nauplii production were lower in Cu, but recovered in pCu, indicating transgenerational plasticity. Strikingly, in F5-F6 nauplii production of Cu-exposed females increased, and did not recover in pCu. The earlier result suggests an increased Cu tolerance while the latter result revealed its cost. In F7, extreme temperature resulted in more pronounced reductions in grazing, and nauplii production of Cu or pCu than in control, supporting TICS. The results suggest that widespread pollution in tropical regions may result in high vulnerability of species in these regions to climate change.

There is an increasing need to accelerate the diffusion of biogas technology, to contribute to handling grand societal challenges. It is thus concerning that around 30% of all biogas projects are abandoned. Previous studies have found that challenges for deployment of bioenergy technology are mainly economic and financial challenges, market and infrastructure challenges, regulatory and administrative challenges, local opposition, site selection challenges and ecological aspects. Very few studies have however tried to understand how these different types of challenges specifically affect individual biogas projects. Also, no previous studies have identified where these challenges occur in the different phases of a project’s lifecycle (conceptualization, planning, and execution). A lack of understanding that limits the ability of both public institutions and project owners to ensure the success of biogas projects. The aim of this study is to fill this knowledge gap and provide a unique insight into the often very complex and long project lifecycle for the realization of centralized biogas projects. Results based on five comprehensive longitudinal case studies of attempts to realize centralized biogas projects, all taking place between 2008–2020 in Denmark, provide insight into how projects are specially affected by these different types of challenges, and shows that both successful and abandoned projects typically faced an array of challenges that project owners need to overcome. The study also from a bottom-up perspective provides insight into the implementation of national policies and initiatives assigned to the accelerated deployment of biogas technology in Denmark between 2008–2020 as well as critical factors at the local level driving the development.