Background： The objective of this study was to investigate the effect of dietary restriction and subsequent compensatory growth on the relative expression of genes involved in volatile fatty acid transport, metabolis...Background： The objective of this study was to investigate the effect of dietary restriction and subsequent compensatory growth on the relative expression of genes involved in volatile fatty acid transport, metabolism and cell proliferation in ruminal epithelial tissue of beef cattle. Sixty Holstein Friesian bulls（mean liveweight 370 ± 35 kg;mean age 479 ± 15 d） were assigned to one of two groups：（i） restricted feed allowance（RES; n = 30） for 125 d（Period 1） followed by ad libitum access to feed for 55 d（Period 2） or（ii） ad libitum access to feed throughout（ADLIB; n = 30）. Target growth rate for RES was 0.6 kg/d during Period 1. At the end of each dietary period, 15 animals from each treatment group were slaughtered and ruminal epithelial tissue and liquid digesta harvested from the ventral sac of the rumen. Real-time q PCR was used to quantify m RNA transcripts of 26 genes associated with ruminal epithelial function. Volatile fatty acid analysis of rumen fluid from individual animals was conducted using gas chromatography.Results： Diet × period interactions were evident for genes involved in ketogenesis（BDH2, P = 0.017）, pyruvate metabolism（LDHa, P = 0.048; PDHA1, P = 0.015） and cellular transport and structure（DSG1, P = 0.019; CACT, P = 0.027）. Ruminal concentrations of propionic acid（P = 0.018） and n-valeric acid（P = 0.029） were lower in RES animals, compared with ADLIB, throughout the experiment. There was also a strong tendency（P = 0.064）toward a diet × period interaction for n-butyric with higher concentrations in RES animals, compared with ADLIB, during Period 1.Conclusions： These data suggest that following nutrient restriction, the structural integrity of the rumen wall is compromised and there is upregulation of genes involved in the production of ketone bodies and breakdown of pyruvate for cellular energy. These results provide an insight into the potential molecular mechanisms regulating ruminal epithelial absorptive metabolism and growth following nutrient restriction and subsequent compensatory growth.展开更多
Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. Modelling approaches minimize the presence of spatial variability of biogeochemical...Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. Modelling approaches minimize the presence of spatial variability of biogeochemical processes, leading to improved estimates of GHGs as well as identifying mitigation and policy options. The comparative performance of the three dynamic models (e.g., DNDC v9.4, DailyDayCent and ECOSSE v5+) with minimum numbers of common input parameters was evaluated against measured variables. Simulations were performed on conventionally-tilled spring barley crops receiving N fertilizer at 135 - 159 kg·N·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup> and crop residues at 3 t·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>. For surface soil nitrate (0 - 10 cm), the ECOSSE and DNDC simulated values showed significant correlations with measured values (R<sup>2</sup> = 0.31 - 0.55, p 0.05). Only the ECOSSE-simulated N<sub>2</sub>O fluxes showed a significant relationship (R<sup>2</sup> = 0.33, p 0.05) with values measured from fertilized fields, but not with unfertilized ones. The DNDC and DailyDayCent models significantly underestimated seasonal/annual N<sub>2</sub>O fluxes compared to ECOSSE, with emission factors (EFs), based on an 8-year average, were 0.09%, 0.31% and 0.52%, respectively. Predictions of ecosystem respiration by both DailyDayCent and DNDC showed reasonable agreement with Eddy Covariance data (R<sup>2</sup> = 0.34 - 0.41, p 0.05). Compared to the measured value (3624 kg·C·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>), the ECOSSE underestimated annual heterotrophic respiration by 7% but this was smaller than the DNDC (50%) and DailyDayCent (24%) estimates. All models simulated CH<sub>4</sub> uptake we展开更多
Aims Plant invasions represent a unique opportunity to study the mechanisms underlying community assembly rules and species distribution patterns.While a superior competitive ability has often been proposed as a major...Aims Plant invasions represent a unique opportunity to study the mechanisms underlying community assembly rules and species distribution patterns.While a superior competitive ability has often been proposed as a major driver of successful plant invasions,its significance depends crucially on the timing of any competitive interaction.We assess whether a mismatch in germination phenology can favor the establishment of alien species,allowing them to exploit vacant niches where competition is low.As well as having important effects on the survival,growth and fitness of a species,asymmetric competition and potential soil legacies resulting from early or late germination can also impact on species recruitment.However,early or late germination comes at a cost,increases the risks of exposure to unfavorable conditions and requires an enhanced abiotic resistance if it is to lead to successful establishment.Important Findings While there are several anecdotal accounts of early and late ger-mination for invasive species,there are limited comparative data with resident species growing under natural conditions.Available evidence from grassland communities indicates that a short-term germination advantage or priority(few days/weeks)provides inva-sive species with a strong competitive advantage over native species and is a critical factor in many invasions.While the exploitation of periods of low competition is a plausible mechanism for the suc-cessful establishment of many invasive plants,direct evidence for this strategy is still scarce.This is particularly true with regard to the exploitation of late germination niches.Consequently,long-term comparative monitoring of the germination phenology of invasive and native plants in situ is needed to assess its significance in a range of ecosystems and its impact on community dynamics.展开更多
Aims Gunnera tinctoria is an unusual N-fixing plant species that has become invasive worldwide,generally in environments with a low evaporative demand and/or high rainfall.Amongst the many mechanisms that may explain ...Aims Gunnera tinctoria is an unusual N-fixing plant species that has become invasive worldwide,generally in environments with a low evaporative demand and/or high rainfall.Amongst the many mechanisms that may explain its success as an introduced species,a contrasting phenology could be important but this may depend on an ability to grow and utilize nutrients under sub-optimal conditions.We examined whether G.tinctoria has an advantage in terms of a contrasting phenology and N-fixing capability,in comparisons with Juncus effusus,the native species most impacted by G.tinctoria invasions.Methods We made phenological assessments on a weekly or bi-weekly basis on long-established populations on Achill Island,Ireland,during 2016-2017.Data on leaf and inflorescence number,total leaf area,light interception and above-ground biomass were collected alongside measurements of soil temperature,moisture and oxidation-reduction potential.The significance of N-fixing ability for supporting seasonal growth was assessed usingδ15N isotopic assessments,together with in situ acetylene reduction measurements.Important Findings The timing of the initiation of growth of G.tinctoria and J.effusus varied between 2016 and 2017,with the earlier emergence and expansion of leaves of G.tinctoria,and the largest above-ground biomass associated with higher water availability.The early growth of G.tinctoria was dependent on preformed structures,with maximum canopy development occurring in late May,prior to that of J.effusus.Whilst N-fixation was observed in March,this made a more significant contribution to growth during the later stages of canopy development.Based onδ15N isotopic analyses,early growth was predominantly associated with N-remobilization from the rhizomes,whilst seedlings were largely reliant on N-fixation.This emphasizes the importance of nutrient mobilization for early growth and shows that the importance of an N-fixing capability may vary developmentally,as well as during different stages of the invasion process.展开更多
Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene f...Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene flow via larval dispersal. Here we review and discuss 4 mechanisms that could generate such unexpected patterns： selection, sweepstakes reproductive success, collective dispersal, and temporal shifts in local population dynamics. First, we review examples where genetic differentiation at specific loci was driven by diversifying selection, which was historically the first process invoked to explain CGP. Second, we turn to neutral demographic processes that may drive genome-wide effects, and whose effects on CGP may be enhanced when they act together. We discuss how sweepstakes reproductive success accelerates genetic drift and can thus generate genetic structure, provided that gene flow is not too strong. Collective dispersal is another mechanism whereby genetic structure can be maintained regardless of dispersal intensity, because it may prevent larval cohorts from becoming entirely mixed. Theoretical analyses of both the sweepstakes and the collective dispersal ideas are presented. Finally, we discuss an idea that has received less attention than the other ones just mentioned, namely temporal shifts in local population dynamics.展开更多
Almost everyone now seems to have a view about alien plant introductions and their significance and there is an ever increasing body of information,both in the scien-tific and popular press,about the dangers of allowi...Almost everyone now seems to have a view about alien plant introductions and their significance and there is an ever increasing body of information,both in the scien-tific and popular press,about the dangers of allowing the uncontrolled spread of alien species.Virtually all possible impacts of plant invasions have been reported,including alterations in biogeochemical cycling,disruption of food webs,alterations in plant-plant,plant-insect and plant-microbe interactions and reductions in biodiversity,leading to the proposal that this is resulting in the creation of novel or emerging ecosystems that have no historical analogue(Hobbs et al.2009).展开更多
Carbon(C)and nitrogen(N)coupling processes in terrestrial ecosystems have the potential to modify the sensitivity of the global C cycle to climate change.But the degree to which C–N interactions contribute to the seq...Carbon(C)and nitrogen(N)coupling processes in terrestrial ecosystems have the potential to modify the sensitivity of the global C cycle to climate change.But the degree to which C–N interactions contribute to the sequestration of terrestrial ecosystem C(C_(seq)),both now and in the future,remains uncertain.In this study,we used a meta-analysis to quantitatively synthesize C and N responses from feld experiments on grasslands subjected to simulated warming and assessed the relative importance of three properties(changes in ecosystem N amount,redistribution of N among soil,litter and vegetation,and modifcations in the C:N ratio)associated with grassland C_(seq) in response to warming.Warming increased soil,litter and vegetation C:N ratios and approximately 2%of N shifted from the soil to vegetation and litter.Warming-induced grassland C_(seq) was the result of the net balance between increases in vegetation and litter C(111.2 g·m^(−2))and decreases in soil C(30.0 g·m^(−2)).Warming-induced accumulation of C stocks in grassland ecosystems indicated that the three processes examined were the main contributors to C_(seq),with the changes in C:N ratios in soil,litter and vegetation as the major contributors,followed by N redistribution,whilst a decrease in total N had a negative effect on C_(seq).These results indicate that elevated temperatures have a signifcant infuence on grassland C and N stocks and their coupling processes,suggesting that ecological models need to include C–N interactions for more accurate predictions of future terrestrial C storage.展开更多
Background:Limited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.Methods:Three farmlet types were investigated in terms of their ...Background:Limited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.Methods:Three farmlet types were investigated in terms of their nutritive value:Lolium perenne(LP);L.perenne+Trifolium repens(LP+TR);and a multispecies sward containing grasses,legumes and herbs(MSS).Farmlets were stocked with beef steers(2.5 livestock units ha−1),grazed on a 1 ha scale to 6 cm(MSS)and 4 cm(LP and LP+TR)residuals.Results:A greater ash concentration was found in MSS than LP(84 vs.75 g kg−1 DM).Both LP+TR and MSS had higher crude protein and lower neutral detergent fibre concentrations than LP.The relative ranking of water soluble carbohydrate and dry matter(DM)concentration was LP>LP+TR>MSS.Despite the leaf component of the LP farmlet contributing more to herbage DM,the organic matter digestibilities of the swards were similar.Conclusions:The MSS and LP+TR farmlets achieved similar forage quality under intensive grazing to LP.However,it is worth noting that MSS had a higher concentration of acid detergent lignin,which can negatively impact digestibility.Further investigation is needed to determine optimal grazing management practices that can minimise the effects of higher lignin concentration on digestibility in multispecies swards.展开更多
Widespread adoption of electric vehicles(EVs)is a common and critical component of international strategies to mitigate environmental pollution,climate change and oil dependency.The ability of consumers to assess the ...Widespread adoption of electric vehicles(EVs)is a common and critical component of international strategies to mitigate environmental pollution,climate change and oil dependency.The ability of consumers to assess the total cost of ownership(TCO)of EVs relative to internal combustion engine vehicles(ICEVs)remains an important factor for EV uptake.The TCO of vehicles is not universal across different car segments and user profiles.We analyse and compare the TCO of ICEVs and EVs from 17 car segments across short-and long-term ownership periods,and further advance existing TCO approaches by integrating detailed activity-based driving profiles,taxation,grant structures and pricing.Results show that EV options in the most popular Irish car segments have existing battery EV options with a TCO averaging respectively 26% and 42% less than their equivalent petrol and diesel ICEV options over a 4-year ownership term when the current grant is included.This integrated method for granular TCO evaluation offers important insights for this market and affords scope to investigate how changes in travel patterns,car-segment pricing,taxation,grant policy,fuel costs,and carbon pricing and other transport policies can all affect TCO values over time across a broad range of market offerings.展开更多
基金funded through Science Foundation Ireland(SFI)contract no 09/RFP/GEN2447
文摘Background： The objective of this study was to investigate the effect of dietary restriction and subsequent compensatory growth on the relative expression of genes involved in volatile fatty acid transport, metabolism and cell proliferation in ruminal epithelial tissue of beef cattle. Sixty Holstein Friesian bulls（mean liveweight 370 ± 35 kg;mean age 479 ± 15 d） were assigned to one of two groups：（i） restricted feed allowance（RES; n = 30） for 125 d（Period 1） followed by ad libitum access to feed for 55 d（Period 2） or（ii） ad libitum access to feed throughout（ADLIB; n = 30）. Target growth rate for RES was 0.6 kg/d during Period 1. At the end of each dietary period, 15 animals from each treatment group were slaughtered and ruminal epithelial tissue and liquid digesta harvested from the ventral sac of the rumen. Real-time q PCR was used to quantify m RNA transcripts of 26 genes associated with ruminal epithelial function. Volatile fatty acid analysis of rumen fluid from individual animals was conducted using gas chromatography.Results： Diet × period interactions were evident for genes involved in ketogenesis（BDH2, P = 0.017）, pyruvate metabolism（LDHa, P = 0.048; PDHA1, P = 0.015） and cellular transport and structure（DSG1, P = 0.019; CACT, P = 0.027）. Ruminal concentrations of propionic acid（P = 0.018） and n-valeric acid（P = 0.029） were lower in RES animals, compared with ADLIB, throughout the experiment. There was also a strong tendency（P = 0.064）toward a diet × period interaction for n-butyric with higher concentrations in RES animals, compared with ADLIB, during Period 1.Conclusions： These data suggest that following nutrient restriction, the structural integrity of the rumen wall is compromised and there is upregulation of genes involved in the production of ketone bodies and breakdown of pyruvate for cellular energy. These results provide an insight into the potential molecular mechanisms regulating ruminal epithelial absorptive metabolism and growth following nutrient restriction and subsequent compensatory growth.
文摘Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. Modelling approaches minimize the presence of spatial variability of biogeochemical processes, leading to improved estimates of GHGs as well as identifying mitigation and policy options. The comparative performance of the three dynamic models (e.g., DNDC v9.4, DailyDayCent and ECOSSE v5+) with minimum numbers of common input parameters was evaluated against measured variables. Simulations were performed on conventionally-tilled spring barley crops receiving N fertilizer at 135 - 159 kg·N·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup> and crop residues at 3 t·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>. For surface soil nitrate (0 - 10 cm), the ECOSSE and DNDC simulated values showed significant correlations with measured values (R<sup>2</sup> = 0.31 - 0.55, p 0.05). Only the ECOSSE-simulated N<sub>2</sub>O fluxes showed a significant relationship (R<sup>2</sup> = 0.33, p 0.05) with values measured from fertilized fields, but not with unfertilized ones. The DNDC and DailyDayCent models significantly underestimated seasonal/annual N<sub>2</sub>O fluxes compared to ECOSSE, with emission factors (EFs), based on an 8-year average, were 0.09%, 0.31% and 0.52%, respectively. Predictions of ecosystem respiration by both DailyDayCent and DNDC showed reasonable agreement with Eddy Covariance data (R<sup>2</sup> = 0.34 - 0.41, p 0.05). Compared to the measured value (3624 kg·C·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>), the ECOSSE underestimated annual heterotrophic respiration by 7% but this was smaller than the DNDC (50%) and DailyDayCent (24%) estimates. All models simulated CH<sub>4</sub> uptake we
基金MG and PP were funded by the projects no.15-13491S(Czech Science Foundation)14-36079G Centre of Excellence PLADIAS(Czech Science Foundation)and long-term research development project RVO 67985939(The Czech Academy of Sciences).PP acknowledges support by Praemium Academiae award from The Czech Academy of Sciences.
文摘Aims Plant invasions represent a unique opportunity to study the mechanisms underlying community assembly rules and species distribution patterns.While a superior competitive ability has often been proposed as a major driver of successful plant invasions,its significance depends crucially on the timing of any competitive interaction.We assess whether a mismatch in germination phenology can favor the establishment of alien species,allowing them to exploit vacant niches where competition is low.As well as having important effects on the survival,growth and fitness of a species,asymmetric competition and potential soil legacies resulting from early or late germination can also impact on species recruitment.However,early or late germination comes at a cost,increases the risks of exposure to unfavorable conditions and requires an enhanced abiotic resistance if it is to lead to successful establishment.Important Findings While there are several anecdotal accounts of early and late ger-mination for invasive species,there are limited comparative data with resident species growing under natural conditions.Available evidence from grassland communities indicates that a short-term germination advantage or priority(few days/weeks)provides inva-sive species with a strong competitive advantage over native species and is a critical factor in many invasions.While the exploitation of periods of low competition is a plausible mechanism for the suc-cessful establishment of many invasive plants,direct evidence for this strategy is still scarce.This is particularly true with regard to the exploitation of late germination niches.Consequently,long-term comparative monitoring of the germination phenology of invasive and native plants in situ is needed to assess its significance in a range of ecosystems and its impact on community dynamics.
基金supported by the Brazilian National Council for Scientific and Technological Development(CNPq).M.C.M.received the grant number 205031/2014-5.A.B.G.and L.G.S.were supported by grants from the Spanish Ministerio de Economía y Competitividad(BES-2013-062945 and CTM2015-64728-C2-1-R,respectively).
文摘Aims Gunnera tinctoria is an unusual N-fixing plant species that has become invasive worldwide,generally in environments with a low evaporative demand and/or high rainfall.Amongst the many mechanisms that may explain its success as an introduced species,a contrasting phenology could be important but this may depend on an ability to grow and utilize nutrients under sub-optimal conditions.We examined whether G.tinctoria has an advantage in terms of a contrasting phenology and N-fixing capability,in comparisons with Juncus effusus,the native species most impacted by G.tinctoria invasions.Methods We made phenological assessments on a weekly or bi-weekly basis on long-established populations on Achill Island,Ireland,during 2016-2017.Data on leaf and inflorescence number,total leaf area,light interception and above-ground biomass were collected alongside measurements of soil temperature,moisture and oxidation-reduction potential.The significance of N-fixing ability for supporting seasonal growth was assessed usingδ15N isotopic assessments,together with in situ acetylene reduction measurements.Important Findings The timing of the initiation of growth of G.tinctoria and J.effusus varied between 2016 and 2017,with the earlier emergence and expansion of leaves of G.tinctoria,and the largest above-ground biomass associated with higher water availability.The early growth of G.tinctoria was dependent on preformed structures,with maximum canopy development occurring in late May,prior to that of J.effusus.Whilst N-fixation was observed in March,this made a more significant contribution to growth during the later stages of canopy development.Based onδ15N isotopic analyses,early growth was predominantly associated with N-remobilization from the rhizomes,whilst seedlings were largely reliant on N-fixation.This emphasizes the importance of nutrient mobilization for early growth and shows that the importance of an N-fixing capability may vary developmentally,as well as during different stages of the invasion process.
文摘Chaotic genetic patchiness （CGP） refers to surprising patterns of spatial and temporal genetic structure observed in some marine species at a scale where genetic variation should be efficiently homogenized by gene flow via larval dispersal. Here we review and discuss 4 mechanisms that could generate such unexpected patterns： selection, sweepstakes reproductive success, collective dispersal, and temporal shifts in local population dynamics. First, we review examples where genetic differentiation at specific loci was driven by diversifying selection, which was historically the first process invoked to explain CGP. Second, we turn to neutral demographic processes that may drive genome-wide effects, and whose effects on CGP may be enhanced when they act together. We discuss how sweepstakes reproductive success accelerates genetic drift and can thus generate genetic structure, provided that gene flow is not too strong. Collective dispersal is another mechanism whereby genetic structure can be maintained regardless of dispersal intensity, because it may prevent larval cohorts from becoming entirely mixed. Theoretical analyses of both the sweepstakes and the collective dispersal ideas are presented. Finally, we discuss an idea that has received less attention than the other ones just mentioned, namely temporal shifts in local population dynamics.
文摘Almost everyone now seems to have a view about alien plant introductions and their significance and there is an ever increasing body of information,both in the scien-tific and popular press,about the dangers of allowing the uncontrolled spread of alien species.Virtually all possible impacts of plant invasions have been reported,including alterations in biogeochemical cycling,disruption of food webs,alterations in plant-plant,plant-insect and plant-microbe interactions and reductions in biodiversity,leading to the proposal that this is resulting in the creation of novel or emerging ecosystems that have no historical analogue(Hobbs et al.2009).
基金supported by the Excellent Youth Scholars Program and the Special Project on Hi-Tech Innovation Capacity(KJCX20210416)from Beijing Academy of Agriculture and Forestry Sciences(BAAFS)the National Key Research and Development Program of China(2017YFA0604604).
文摘Carbon(C)and nitrogen(N)coupling processes in terrestrial ecosystems have the potential to modify the sensitivity of the global C cycle to climate change.But the degree to which C–N interactions contribute to the sequestration of terrestrial ecosystem C(C_(seq)),both now and in the future,remains uncertain.In this study,we used a meta-analysis to quantitatively synthesize C and N responses from feld experiments on grasslands subjected to simulated warming and assessed the relative importance of three properties(changes in ecosystem N amount,redistribution of N among soil,litter and vegetation,and modifcations in the C:N ratio)associated with grassland C_(seq) in response to warming.Warming increased soil,litter and vegetation C:N ratios and approximately 2%of N shifted from the soil to vegetation and litter.Warming-induced grassland C_(seq) was the result of the net balance between increases in vegetation and litter C(111.2 g·m^(−2))and decreases in soil C(30.0 g·m^(−2)).Warming-induced accumulation of C stocks in grassland ecosystems indicated that the three processes examined were the main contributors to C_(seq),with the changes in C:N ratios in soil,litter and vegetation as the major contributors,followed by N redistribution,whilst a decrease in total N had a negative effect on C_(seq).These results indicate that elevated temperatures have a signifcant infuence on grassland C and N stocks and their coupling processes,suggesting that ecological models need to include C–N interactions for more accurate predictions of future terrestrial C storage.
基金Department of Agriculture,Food and the Marine Research,Irish Government,Grant/Award Number:RSF 17/S/267:SMARTSWARD。
文摘Background:Limited information is available regarding the nutritive value and structural characteristics of multispecies swards when rotationally grazed.Methods:Three farmlet types were investigated in terms of their nutritive value:Lolium perenne(LP);L.perenne+Trifolium repens(LP+TR);and a multispecies sward containing grasses,legumes and herbs(MSS).Farmlets were stocked with beef steers(2.5 livestock units ha−1),grazed on a 1 ha scale to 6 cm(MSS)and 4 cm(LP and LP+TR)residuals.Results:A greater ash concentration was found in MSS than LP(84 vs.75 g kg−1 DM).Both LP+TR and MSS had higher crude protein and lower neutral detergent fibre concentrations than LP.The relative ranking of water soluble carbohydrate and dry matter(DM)concentration was LP>LP+TR>MSS.Despite the leaf component of the LP farmlet contributing more to herbage DM,the organic matter digestibilities of the swards were similar.Conclusions:The MSS and LP+TR farmlets achieved similar forage quality under intensive grazing to LP.However,it is worth noting that MSS had a higher concentration of acid detergent lignin,which can negatively impact digestibility.Further investigation is needed to determine optimal grazing management practices that can minimise the effects of higher lignin concentration on digestibility in multispecies swards.
基金supported by the China Scholarship Council(CSC)(Grant No.201708300027)the Environmental Protection Agency of Ireland.
文摘Widespread adoption of electric vehicles(EVs)is a common and critical component of international strategies to mitigate environmental pollution,climate change and oil dependency.The ability of consumers to assess the total cost of ownership(TCO)of EVs relative to internal combustion engine vehicles(ICEVs)remains an important factor for EV uptake.The TCO of vehicles is not universal across different car segments and user profiles.We analyse and compare the TCO of ICEVs and EVs from 17 car segments across short-and long-term ownership periods,and further advance existing TCO approaches by integrating detailed activity-based driving profiles,taxation,grant structures and pricing.Results show that EV options in the most popular Irish car segments have existing battery EV options with a TCO averaging respectively 26% and 42% less than their equivalent petrol and diesel ICEV options over a 4-year ownership term when the current grant is included.This integrated method for granular TCO evaluation offers important insights for this market and affords scope to investigate how changes in travel patterns,car-segment pricing,taxation,grant policy,fuel costs,and carbon pricing and other transport policies can all affect TCO values over time across a broad range of market offerings.
