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1.
Science ; 384(6696): 697-703, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38723080

RESUMEN

Changes in climate shift the geographic locations that are suitable for malaria transmission because of the thermal constraints on vector Anopheles mosquitos and Plasmodium spp. malaria parasites and the lack of availability of surface water for vector breeding. Previous Africa-wide assessments have tended to solely represent surface water using precipitation, ignoring many important hydrological processes. Here, we applied a validated and weighted ensemble of global hydrological and climate models to estimate present and future areas of hydroclimatic suitability for malaria transmission. With explicit surface water representation, we predict a net decrease in areas suitable for malaria transmission from 2025 onward, greater sensitivity to future greenhouse gas emissions, and different, more complex, malaria transmission patterns. Areas of malaria transmission that are projected to change are smaller than those estimated by precipitation-based estimates but are associated with greater changes in transmission season lengths.


Asunto(s)
Anopheles , Hidrología , Malaria , Mosquitos Vectores , Animales , Malaria/transmisión , África , Anopheles/parasitología , Mosquitos Vectores/parasitología , Cambio Climático , Humanos , Estaciones del Año , Lluvia , Modelos Teóricos , Agua , Gases de Efecto Invernadero/análisis
2.
Lancet Planet Health ; 8(5): e327-e333, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38729672

RESUMEN

Health care contributes 4·4% of global net carbon emissions. Hospitals are resource-intensive settings, using a large amount of supplies in patient care and have high energy, ventilation, and heating needs. This Viewpoint investigates emissions related to health care in a patient's last year of life. End of life (EOL) is a period when health-care use and associated emissions production increases exponentially due primarily to hospital admissions, which are often at odds with patients' values and preferences. Potential solutions detailed within this Viewpoint are facilitating advanced care plans with patients to ensure their EOL wishes are clear, beginning palliative care interventions earlier when treating a life-limiting illness, deprescribing unnecessary medications because medications and their supply chains make up a significant portion of health-care emissions, and, enhancing access to low-intensity community care settings (eg, hospices) within the last year of life if home care is not available. Our analysis was done using Canadian data, but the findings can be applied to other high-income countries.


Asunto(s)
Gases de Efecto Invernadero , Cuidado Terminal , Humanos , Canadá , Gases de Efecto Invernadero/análisis
3.
PLoS One ; 19(5): e0301254, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38713689

RESUMEN

Oil seed crops are the second most important field crops after cereals in the agricultural economy globally. The use and demand for oilseed crops such as groundnut, soybean and sunflower have grown significantly, but climate change is expected to alter the agroecological conditions required for oilseed crop production. This study aims to present an approach that utilizes decision-making tools to assess the potential climate change impacts on groundnut, soybean and sunflower yields and the greenhouse gas emissions from the management of the crops. The Decision Support Tool for Agrotechnology Transfer (DSSAT v4.7), a dynamic crop model and the Cool Farm Tool, a GHG calculator, was used to simulate yields and estimate GHG emissions from these crops, respectively. Four representative concentration pathways (RCPs 2.6, 4.5, 6.0, and 8.5), three nitrogen (0, 75, and 150 kg/ha) and phosphorous (0, 30 and 60 P kg/ha) fertilizer rates at three sites in Limpopo, South Africa (Ofcolaco, Syferkuil and Punda Maria) were used in field trials for calibrating the models. The highest yield was achieved by sunflower across all crops, years and sites. Soybean yield is projected to decrease across all sites and scenarios by 2030 and 2050, except at Ofcolaco, where yield increases of at least 15.6% is projected under the RCP 4.5 scenario. Positive climate change impacts are predicted for groundnut at Ofcolaco and Syferkuil by 2030 and 2050, while negative impacts with losses of up to 50% are projected under RCP8.5 by 2050 at Punda Maria. Sunflower yield is projected to decrease across all sites and scenarios by 2030 and 2050. A comparison of the climate change impacts across sites shows that groundnut yield is projected to increase under climate change while notable yield losses are projected for sunflower and soybean. GHG emissions from the management of each crop showed that sunflower and groundnut production had the highest and lowest emissions across all sites respectively. With positive climate change impacts, a reduction of GHG emissions per ton per hectare was projected for groundnuts at Ofcolaco and Syferkuil and for sunflower in Ofcolaco in the future. However, the carbon footprint from groundnut is expected to increase by 40 to 107% in Punda Maria for the period up to 2030 and between 70-250% for 2050, with sunflower following a similar trend. We conclude that climate change will potentially reduce yield for oilseed crops while management will increase emissions. Therefore, in designing adaptation measures, there is a need to consider emission effects to gain a holistic understanding of how both climate change impacts on crops and mitigation efforts could be targeted.


Asunto(s)
Cambio Climático , Productos Agrícolas , Productos Agrícolas/crecimiento & desarrollo , Sudáfrica , Semillas/crecimiento & desarrollo , Glycine max/crecimiento & desarrollo , Helianthus/crecimiento & desarrollo , Modelos Teóricos , Fertilizantes/análisis , Gases de Efecto Invernadero/análisis , Aceites de Plantas , Agricultura/métodos
4.
Environ Sci Technol ; 58(19): 8360-8371, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38701334

RESUMEN

Artificial channels, common features of inland waters, have been suggested as significant contributors to methane (CH4) and carbon dioxide (CO2) dynamics and emissions; however, the magnitude and drivers of their CH4 and CO2 emissions (diffusive and ebullitive) remain unclear. They are characterized by reduced flow compared to the donor river, which results in suspended organic matter (OM) accumulation. We propose that in such systems hydrological controls will be reduced and OM accumulation will control emissions by promoting methane production and outgassing. Here, we monitored summertime CH4 and CO2 concentrations and emissions on six newly constructed river-fed artificial channels, from bare riparian mineral soil to lotic channels, under two distinct flow regimes. Chamber-based fluxes were complemented with hydrology, total fluxes (diffusion + ebullition), and suspended OM accumulation assessments. During the first 6 weeks after the flooding, inflowing riverine water dominated the emissions over in-channel contributions. Afterwards, a substantial accumulation of riverine suspended OM (≥50% of the channel's volume) boosted in-channel methane production and led to widespread ebullition 10× higher than diffusive fluxes, regardless of the flow regime. Our finding suggests ebullition as a dominant pathway in these anthropogenic systems, and thus, their impact on regional methane emissions might have been largely underestimated.


Asunto(s)
Gases de Efecto Invernadero , Hidrología , Metano , Ríos/química , Dióxido de Carbono , Monitoreo del Ambiente
5.
Environ Monit Assess ; 196(6): 563, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771410

RESUMEN

The greenhouse gas (GHG) emissions inventories in our context result from the production of electricity from fuel oil at the Mbalmayo thermal power plant between 2016 and 2020. Our study area is located in the Central Cameroon region. The empirical method of the second level of industrialisation was applied to estimate GHG emissions and the application of the genetic algorithm-Gaussian (GA-Gaussian) coupling method was used to optimise the estimation of GHG emissions. Our work is of an experimental nature and aims to estimate the quantities of GHG produced by the Mbalmayo thermal power plant during its operation. The search for the best objective function using genetic algorithms is designed to bring us closer to the best concentration, and the Gaussian model is used to estimate the concentration level. The results obtained show that the average monthly emissions in kilograms (kg) of GHGs from the Mbalmayo thermal power plant are: 526 kg for carbon dioxide (CO2), 971.41 kg for methane (CH4) and 309.41 kg for nitrous oxide (N2O), for an average monthly production of 6058.12 kWh of energy. Evaluation of the stack height shows that increasing the stack height helps to reduce local GHG concentrations. According to the Cameroonian standards published in 2021, the limit concentrations of GHGs remain below 30 mg/m3 for CO2 and 200 µg/m3 for N2O, while for CH4 we reach the limit value of 60 µg/m3. These results will enable the authorities to take appropriate measures to reduce GHG concentrations.


Asunto(s)
Contaminantes Atmosféricos , Algoritmos , Monitoreo del Ambiente , Gases de Efecto Invernadero , Metano , Centrales Eléctricas , Gases de Efecto Invernadero/análisis , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Camerún , Metano/análisis , Dióxido de Carbono/análisis , Óxido Nitroso/análisis , Contaminación del Aire/estadística & datos numéricos , Distribución Normal
6.
Lasers Med Sci ; 39(1): 134, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771416

RESUMEN

PURPOSE: Climate change has serious consequences for our wellbeing. Healthcare systems themselves contribute significantly to our total carbon footprint, of which emissions from surgical practice are a major component. The primary sources of emissions identified are anaesthetic gases, disposal of single-use equipment, energy usage, and travel to and from clinical areas. We sought to quantify the waste generated by laser surgery which, to our knowledge, has not been previously reported. METHODS: The carbon footprint of two laser centres operating within the United Kingdom were measured. The internationally recognised Greenhouse Gas Protocol was used as a guiding framework to classify sources of waste and conversion factors issued by the UK government were used to quantify emissions. RESULTS: The total carbon footprints per day at each unit were 299.181 carbon dioxide equivalents (kgCo2eq) and 121.512 kgCO2eq, respectively. We found the carbon footprint of individual laser treatments to be approximately 15 kgCO2eq per procedure. The biggest overall contributor to the carbon footprint was found to be the emissions generated from staff, patient and visitor travel. This was followed by electricity usage, and indirect emissions from physical waste and laundry. CONCLUSIONS: The carbon footprint of laser procedures was considerably less than the average surgical operation in the UK. This initial study measures the carbon footprint of a laser center in a clinical setting and allows us to identify where improvements can be made to eventually achieve a net carbon zero health care system.


Asunto(s)
Huella de Carbono , Huella de Carbono/estadística & datos numéricos , Reino Unido , Humanos , Terapia por Láser/métodos , Terapia por Láser/estadística & datos numéricos , Gases de Efecto Invernadero/análisis , Dióxido de Carbono/análisis
7.
Trop Anim Health Prod ; 56(5): 172, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771474

RESUMEN

The increasing global demand for food and the strong effect of climate change have forced animal science to advance regarding new methods of selection in search of more efficient animals in production systems. Feed consumption represents more than 70% of the costs of sheep farms, and more efficient animals can increase the farmers' profitability. One of the main measures of feed efficiency is estimated residual feed intake (RFI), created in 1963 by Robert Koch for estimation in cattle and later adapted for sheep. Animals with negative RFI values (RFI-) are more efficient than animals with positive values (RFI+), with influence on the variables of performance, carcass quality and production of enteric gases. The RFI is the most common and accepted metric of the feed efficiency trait for genetic selection, since it is independent of growth traits, unlike the feed conversion ratio. The purpose of this review article was to present updated literature information on the relationship of RFI estimates with performance measures, molecular markers, greenhouse gas production and feed efficiency, the technical aspects and physiological basis of metabolic in sheep.


Asunto(s)
Alimentación Animal , Animales , Alimentación Animal/análisis , Crianza de Animales Domésticos/métodos , Ingestión de Alimentos/fisiología , Ovinos/fisiología , Ovinos/crecimiento & desarrollo , Oveja Doméstica/fisiología , Oveja Doméstica/crecimiento & desarrollo , Fenómenos Fisiológicos Nutricionales de los Animales , Gases de Efecto Invernadero/análisis
8.
Nutr J ; 23(1): 55, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762743

RESUMEN

BACKGROUND: Assessing the trends in dietary GHGE considering the social patterning is critical for understanding the role that food systems have played and will play in global emissions in countries of the global south. Our aim is to describe dietary greenhouse gas emissions (GHGE) trends (overall and by food group) using data from household food purchase surveys from 1989 to 2020 in Mexico, overall and by education levels and urbanicity. METHODS: We used cross-sectional data from 16 rounds of Mexico's National Income and Expenditure Survey, a nationally representative survey. The sample size ranged from 11,051 in 1989 to 88,398 in 2020. We estimated the mean total GHGE per adult-equivalent per day (kg CO2-eq/ad-eq/d) for every survey year. Then, we estimated the relative GHGE contribution by food group for each household. These same analyses were conducted stratifying by education and urbanicity. RESULTS: The mean total GHGE increased from 3.70 (95%CI: 3.57, 3.82) to 4.90 (95% CI 4.62, 5.18) kg CO2-eq/ad-eq/d between 1989 and 2014 and stayed stable between 4.63 (95% CI: 4.53, 4.72) and 4.89 (95% CI: 4.81, 4.96) kg CO2-eq/ad-eq/d from 2016 onwards. In 1989, beef (19.89%, 95% CI: 19.18, 20.59), dairy (16.87%, 95% CI: 16.30, 17.42)), corn (9.61%, 95% CI: 9.00, 10.22), legumes (7.03%, 95% CI: 6.59, 7.46), and beverages (6.99%, 95% CI: 6.66, 7.32) had the highest relative contribution to food GHGE; by 2020, beef was the top contributor (17.68%, 95%CI: 17.46, 17.89) followed by fast food (14.17%, 95% CI: 13.90, 14.43), dairy (11.21%, 95%CI: 11.06, 11.36), beverages (10.09%, 95%CI: 9.94, 10.23), and chicken (10.04%, 95%CI: 9.90, 10.17). Households with higher education levels and those in more urbanized areas contributed more to dietary GHGE across the full period. However, households with lower education levels and those in rural areas had the highest increase in these emissions from 1989 to 2020. CONCLUSIONS: Our results provide insights into the food groups in which the 2023 Mexican Dietary Guidelines may require to focus on improving human and planetary health.


Asunto(s)
Gases de Efecto Invernadero , México , Gases de Efecto Invernadero/análisis , Humanos , Estudios Transversales , Bebidas/estadística & datos numéricos , Dieta/estadística & datos numéricos , Dieta/tendencias , Alimentos/estadística & datos numéricos , Efecto Invernadero , Composición Familiar
9.
J Environ Manage ; 359: 120848, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38696850

RESUMEN

This study investigates the least-cost decarbonization pathways in the Finnish electricity generation industry in order to achieve the national carbon neutrality goal by 2035. Various abatement measures, such as downscaling production, capital investment, and increasing labor and intermediate inputs, are considered. The marginal abatement costs (MACs) of greenhouse gas emissions are estimated using the convex quantile regression method and applied to unique register-based firm-level greenhouse gas emission data merged with financial statement data. We adjust the MAC estimates for the sample selection bias caused by zero-emission firms by applying the two-stage Heckman correction. Our empirical findings reveal that the median MAC ranges from 0.1 to 3.5 euros per tonne of CO2 equivalent. The projected economic cost of a 90% reduction in emissions is 62 million euros, while the estimated cost of achieving zero emissions is 83 million euros.


Asunto(s)
Electricidad , Finlandia , Gases de Efecto Invernadero/análisis , Dióxido de Carbono/análisis
10.
J Environ Manage ; 359: 121055, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38701585

RESUMEN

Globally, forest soils are considered as important sources and sinks of greenhouse gases (GHGs). However, most studies on forest soil GHG fluxes are confined to the topsoils (above 20 cm soil depths), with only very limited information being available regarding these fluxes in the subsoils (below 20 cm soil depths), especially in managed forests. This limits deeper understanding of the relative contributions of different soil depths to GHG fluxes and global warming potential (GWP). Here, we used a concentration gradient-based method to comprehensively investigate the effects of thinning intensity (15% vs. 35%) and nutrient addition (no fertilizer vs. NPK fertilizers) on soil GHG fluxes from the 0-40 cm soil layers at 10 cm depth intervals in a Chinese fir (Cunninghamia lanceolata) plantation. Results showed that forest soils were the sources of CO2 and N2O, but the sinks of CH4. Soil GHG fluxes decreased with increasing soil depth, with the 0-20 cm soil layers identified as the dominant producers of CO2 and N2O and consumers of CH4. Thinning intensity did not significantly affect soil GHG fluxes. However, fertilization significantly increased CO2 and N2O emissions and CH4 uptake at 0-20 cm soil layers, but decreased them at 20-40 cm soil layers. This is because fertilization alleviated microbial N limitation and decreased water filled pore space (WFPS) in topsoils, while it increased WFPS in subsoils, ultimately suggesting that soil WFPS and N availability (especially NH4+-N) were the predominant regulators of GHG fluxes along soil profiles. Generally, there were positive interactive effects of thinning and fertilization on soil GHG fluxes. Moreover, the 35% thinning intensity without fertilization had the lowest GWP among all treatments. Overall, our results suggest that fertilization may not only cause depth-dependent effects on GHG fluxes within soil profiles, but also impede efforts to mitigate climate change by promoting GHG emissions in managed forest plantations.


Asunto(s)
Fertilizantes , Gases de Efecto Invernadero , Suelo , Gases de Efecto Invernadero/análisis , Suelo/química , Bosques , Metano/análisis , Dióxido de Carbono/análisis , Cunninghamia/crecimiento & desarrollo , Calentamiento Global , Óxido Nitroso/análisis , China
11.
Chemosphere ; 358: 142186, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38701860

RESUMEN

Fluorinated compounds (FCs) such as sulfur hexafluoride (SF6) and nitrogen trifluoride (NF3) have garnered attention due to their environmental impact. This study investigates the mineralization and removal of two potent FCs: SF6 and NF3. The results confirm that utilizing various oxalate salts leads to the formation of corresponding metallic fluorides: lithium fluoride (LiF), sodium fluoride (NaF), and potassium fluoride (KF), validating the occurrence of mineralization reactions. Among the oxalate salts, sodium oxalate demonstrates the highest mineralization efficiency in both SF6 and NF3 removal. Real-time Fourier transform infrared spectroscopy (FT-IR) gas-phase analysis confirms rapid and complete gas removal within a short reaction time using the selected oxalate salts. Meticulous mass balance calculations revealed that oxalates (LiF, NaF, and KF) yielded sulfur (S) at rates of 92.09%, 91.85%, and 84.98% following SF6 mineralization. Additionally, the conversion rates of oxalates to the corresponding metallic fluorides (LiF, NaF, and KF) after SF6 mineralization were 98.18%, 95.82%, and 95.21%, respectively. Similarly, after NF3 mineralization, these conversion rates stood at 92.18%, 90.67%, and 90.02%, respectively. The removal efficiencies for SF6 (1000 ppm) were 4.98, 12.01, and 7.23 L/g, while those for NF3 (1000 ppm) were 14.1, 12.6, and 11.7 L/g, respectively. Notably, sodium oxalate exhibits superior effectiveness, achieving 100% SF6 conversion within 30 min and 100% NF3 conversion within 50 min. This work underscores the potential of oxalate mineralization as a promising strategy for efficient and rapid removal of potent fluorinated compounds, paving the way for environmentally benign FC remediation techniques with broader implications for sustainable gas treatment technologies.


Asunto(s)
Fluoruros , Gases de Efecto Invernadero , Oxalatos , Hexafluoruro de Azufre , Oxalatos/química , Hexafluoruro de Azufre/química , Fluoruros/química , Gases de Efecto Invernadero/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Restauración y Remediación Ambiental/métodos
12.
Sci Total Environ ; 931: 172942, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38719032

RESUMEN

Biochar is increasingly used in climate-smart agriculture, yet its impact on greenhouse gas (GHG) emissions and soil carbon (C) sequestration remains poorly understood. This study examined biochar-mediated changes in soil properties and their contribution to C stabilization and GHG mitigation by evaluating four types of biochar. Soil carbon dioxide (CO2) and nitrous oxide (N2O) emissions, soil chemical and biological properties, and soil organic carbon (SOC) mineralization kinetics were monitored using greenhouse, laboratory, and modeling experiments. Three pine wood biochars pyrolyzed at 460 °C (PB-460), 500 °C (PB-500), 700 °C (PB-700), and one pine bark biochar from gasification at 760 °C (GB-760) were added into soil at 1 % w/w basis. Soils amended with biochar were used to cultivate sorghum for three months in a greenhouse, followed by three months of laboratory incubation. Data obtained from laboratory incubation was modeled using various statistical approaches. The PB-500 and PB-700 reduced cumulative N2O-N emissions by 68.5 % and 73.9 % and CO2 equivalent C emissions by 66.9 % and 72.4 %, respectively, compared to unamended control. The N2O emissions were positively associated with soil nitrate N, available P, and biochar ash content while negatively associated with SOC. The CO2 emission was negatively related to biochar C:N ratio and volatile matter content. Biochar amended soils had 49.2 % (PB-500) to 87.7 % (PB-700) greater SOC and 22.9 % (PB-700) to 48.1 % (GB-760) greater sorghum yield than the control. While PB-700 had more saprophytes than the control, the GB-760 yielded a greater yield than biochars prepared by pyrolysis. Microbial biomass C was 7.23 to 23.3 % greater in biochar amended soils than in control. The double exponential decay model best explained the dynamics of C mineralization, which was associated with initial soil nitrate N and available P positively and total fungi and protozoa biomass negatively. Biochar amendment could be a climate smart agricultural strategy. Pyrolysis pine wood biochar showed the greatest potential to reduce GHG emissions and enhance SOC storage and stability, and gasification biochar contributed more to SOC storage and increased crop yield.


Asunto(s)
Carbono , Carbón Orgánico , Gases de Efecto Invernadero , Suelo , Carbón Orgánico/química , Suelo/química , Gases de Efecto Invernadero/análisis , Carbono/análisis , Bosques , Secuestro de Carbono , Óxido Nitroso/análisis , Dióxido de Carbono/análisis , Agricultura/métodos , Contaminantes Atmosféricos/análisis
13.
Nat Commun ; 15(1): 4151, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755154

RESUMEN

Atmospheric methane oxidizing bacteria (atmMOB) constitute the sole biological sink for atmospheric methane. Still, the physiological basis allowing atmMOB to grow on air is not well understood. Here we assess the ability and strategies of seven methanotrophic species to grow with air as sole energy, carbon, and nitrogen source. Four species, including three outside the canonical atmMOB group USCα, enduringly oxidized atmospheric methane, carbon monoxide, and hydrogen during 12 months of growth on air. These four species exhibited distinct substrate preferences implying the existence of multiple metabolic strategies to grow on air. The estimated energy yields of the atmMOB were substantially lower than previously assumed necessary for cellular maintenance in atmMOB and other aerobic microorganisms. Moreover, the atmMOB also covered their nitrogen requirements from air. During growth on air, the atmMOB decreased investments in biosynthesis while increasing investments in trace gas oxidation. Furthermore, we confirm that a high apparent specific affinity for methane is a key characteristic of atmMOB. Our work shows that atmMOB grow on the trace concentrations of methane, carbon monoxide, and hydrogen present in air and outlines the metabolic strategies that enable atmMOB to mitigate greenhouse gases.


Asunto(s)
Monóxido de Carbono , Hidrógeno , Metano , Oxidación-Reducción , Metano/metabolismo , Monóxido de Carbono/metabolismo , Hidrógeno/metabolismo , Atmósfera/química , Aire , Nitrógeno/metabolismo , Gases de Efecto Invernadero/metabolismo
14.
Animal ; 18(5): 101158, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38703756

RESUMEN

The transformation of pastures from a degraded state to sustainable productivity is a major challenge in tropical livestock production. Stoloniferous forage legumes such as Arachis pintoi (forage peanut) are one of the most promising alternatives for intensifying pasture-based beef livestock operations with reduced greenhouse gas (GHG) emissions. This 2-year study assessed beef cattle performance, nutrient intake and digestibility, and balance of GHG emissions in three pasture types (PT): (1) mixed Palisade grass - Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster (syn. Brachiaria brizantha Stapf cv. Marandu) and forage peanut (A. pintoi Krapov. & W.C. Greg. cv. BRS Mandobi) pastures (Mixed), (2) monoculture Palisade grass pastures with 150 kg of N/ha per year (Fertilised), and (3) monoculture Palisade grass without N fertiliser (Control). Continuous stocking with a variable stocking rate was used in a randomised complete block design, with four replicates per treatment. The average daily gain and carcass gain were not influenced by the PT (P = 0.439 and P = 0.100, respectively) and were, on average, 0.433 kg/animal per day and 83.4 kg/animal, respectively. Fertilised and Mixed pastures increased by 102 and 31.5%, respectively, the liveweight gain per area (kg/ha/yr) compared to the Control pasture (P < 0.001). The heifers in the Mixed pasture had lower CH4 emissions (g/animal per day; P = 0.009), achieving a reduction of 12.6 and 10.1% when compared to the Fertilised and Control pastures, respectively. Annual (N2O) emissions (g/animal) and per kg carcass weight gain were 59.8 and 63.1% lower, respectively, in the Mixed pasture compared to the Fertilised pasture (P < 0.001). Mixed pasture mitigated approximately 23% of kg CO2eq/kg of carcass when substituting 150 kg of N/ha per year via fertiliser. Mixed pastures with forage peanut are a promising solution to recover degraded tropical pastures by providing increased animal production with lower GHG emissions.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos , Arachis , Gases de Efecto Invernadero , Animales , Bovinos/fisiología , Alimentación Animal/análisis , Gases de Efecto Invernadero/análisis , Crianza de Animales Domésticos/métodos , Dieta/veterinaria , Masculino , Femenino , Fenómenos Fisiológicos Nutricionales de los Animales , Digestión , Fabaceae
15.
Environ Sci Technol ; 58(19): 8349-8359, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696360

RESUMEN

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the Australian government, in compliance with the Paris Agreement. Total annual methane emissions increased by 58% from 1990 (26 kilotons CH4 year-1) to 2022 (41 kilotons CH4 year-1). This increase is linked to the water surface of agricultural ponds growing by 51% between 1990 (115 kilo hectares; 1,150 km2) and 2022 (173 kilo hectares; 1,730 km2). In Australia, 16,000 new agricultural ponds are built annually, expanding methane-emitting water surfaces by 1,230 ha yearly (12.3 km2 year-1). On average, the methane flux of agricultural ponds in Australia is 0.238 t CH4 ha-1 year-1. These results offer policymakers insights into developing targeted mitigation strategies to curb these specific forms of anthropogenic emissions. For instance, financial incentives, such as carbon or biodiversity credits, can mobilize widespread investments toward reducing greenhouse gas emissions and enhancing the ecological and environmental values of agricultural ponds. Our data and modeling tools are available on a free cloud-based platform for other countries to adopt this approach.


Asunto(s)
Agricultura , Gases de Efecto Invernadero , Metano , Estanques , Metano/análisis , Gases de Efecto Invernadero/análisis , Australia , Monitoreo del Ambiente , Cambio Climático
16.
Sci Total Environ ; 932: 173066, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38729366

RESUMEN

Agriculture activity contributes to greenhouse gas (GHG) emissions through its utilization of land, water, and energy for food production. Hence, the interactions between land, water, and GHG emissions in agricultural production need to be comprehensively studied. The study aimed to assess the Land-Water-GHG-Food Nexus Index (LWGFNI) of rice cultivation across various land suitability classes in Central Thailand and determining the physical, socio-economic, and policy factors that can influence farmers' decisions to choose for cultivating rice instead of shifting to other crops. The results indicated that the highest LWGFNI score was 0.69 for the rice grown in the moderate suitability land class which revealed a lower use of land and water resources as well as GHG emissions compared to other levels of land suitability. The LWGFNI scores of major rice cultivation were greater compared to the second rice in all four-land suitability. The use of fertilizers had a crucial role in enhancing productivity levels and was a significant factor in the generation of GHG emissions. Hence, improving effective production should consider the appropriate use of fertilizer. The physical, socio-economic, and policy-related aspects that significantly influenced farmers' decisions on cultivation of rice included topography, water resources, inherited professions, price guarantee, and knowledge/training factors. The methodology used and results obtained can help policy makers to plan the use of water and land resources efficiently and appropriately with local resources based on land suitability class. The assessment results revealed the GHG hotspots and the strategies to mitigate GHG emissions associated with rice cultivation.


Asunto(s)
Agricultura , Gases de Efecto Invernadero , Oryza , Oryza/crecimiento & desarrollo , Tailandia , Agricultura/métodos , Gases de Efecto Invernadero/análisis , Factores Socioeconómicos , Productos Agrícolas/crecimiento & desarrollo , Fertilizantes/análisis
17.
Huan Jing Ke Xue ; 45(5): 2891-2904, 2024 May 08.
Artículo en Chino | MEDLINE | ID: mdl-38629551

RESUMEN

The increasing use of nitrogen fertilizers exerts extreme pressure on the environment (e.g., greenhouse gas emissions, GHGs) for winter wheat-summer maize rotation systems in the North China Plain. The application of controlled-release fertilizers is considered as an effective measure to improve crop yield and nitrogen fertilizer utilization efficiency. To explore the impact of one-time fertilization of controlled-release blended fertilizer on crop yield and GHGs of a wheat-maize rotation system, field experiments were carried out in Dezhou Modern Agricultural Science and Technology Park from 2020 to 2022. Five treatments were established for both winter wheat and summer maize, including no nitrogen control (CK), farmers' conventional nitrogen application (FFP), optimized nitrogen application (OPT), CRU1 (the blending ratio of coated urea and traditional urea on winter wheat and summer maize was 5:5 and 3:7, respectively), and CRU2 (the blending ratio of coated urea and traditional urea on winter wheat and summer maize was 7:3 and 5:5, respectively). The differences in yield, nitrogen fertilizer utilization efficiency, fertilization economic benefits, and GHGs among different treatments were compared and analyzed. The results showed that nitrogen application significantly increased the single season and annual crop yields of the wheat-maize rotation system (P < 0.05). Compared with those of FFP, the CRU1 and CRU2 treatments increased the yields of summer maize by 0.4% to 5.6%, winter wheat by -5.4% to 4.1%, and annual yields by -1.1% to 3.9% (P > 0.05). N recovery efficiency (NRE), N agronomic efficiency (NAE), and N partial factor productivity (NPFP) were increased by -8.6%-43.4%, 2.05-6.24 kg·kg-1, and 4.24-10.13 kg·kg-1, respectively. Annual net income increased by 0.2% to 6.3%. Nitrogen application significantly increased the annual emissions of soil N2O and CO2 in the rotation system (P < 0.05) but had no effect on the annual emissions of CH4 (except for in the FFP treatment in the first year). The annual total N2O emissions under the CRU1 and CRU2 treatments were significantly reduced by 23.4% to 30.2% compared to those under the FFP treatment (P < 0.05). Additionally, nitrogen application significantly increased the annual global warming potential (GWP) of the rotation system (P < 0.05), but the intensity of greenhouse gas emissions was reduced due to the increase in crop yields. Compared with that under FFP, the annual GWP under the CRU1 and CRU2 treatments decreased by 9.6% to 11.5% (P < 0.05), and the annual GHGs decreased by 11.2% to 13.8% (P > 0.05). In summary, the one-time application of controlled-release blended fertilizer had a positive role in improving crop yield and economic benefits, reducing nitrogen fertilizer input and labor costs, and GHGs, which is an effective nitrogen fertilizer management measure to promote cleaner production of food crops in the North China Plain.


Asunto(s)
Gases de Efecto Invernadero , Fertilizantes , Triticum , Zea mays , Preparaciones de Acción Retardada , Óxido Nitroso/análisis , Agricultura/métodos , Suelo , China , Nitrógeno , Urea
18.
J Environ Manage ; 357: 120736, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38574706

RESUMEN

Onsite sanitation systems (OSS) are significant sources of greenhouse gases (GHG) including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). While a handful of studies have been conducted on GHG emissions from OSS, systematic evaluation of literature on this subject is limited. Our systematic review and meta-analysis provides state-of-the- art information on GHG emissions from OSS and identifies novel areas for investigation. The paper analyzes GHG emission rates from different OSS, the influence of various design, operational, and environmental factors on emission rates and proffers mitigation measures. Following the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) guidelines, we identified 16 articles which quantified GHG emissions from OSS. Septic tanks emit substantial amounts of CO2 and CH4 ranging from 1.74 to 398.30 g CO2/cap/day and 0.06-110.13 g CH4/cap/day, respectively, but have low N2O emissions (0.01-0.06 g N2O/cap/day). CH4 emissions from pit latrines range from 0.77 to 20.30 g CH4/cap/day N2O emissions range from 0.76 to 1.20 gN2O/cap/day. We observed statistically significant correlations (p < 0.05) between temperature, biochemical oxygen demand, chemical oxygen demand, dissolved oxygen, storage period, and GHG emissions from OSS. However, no significant correlation (p > 0.05) was observed between soil volumetric water content and CO2 emissions. CH4 emissions (expressed as CO2 equivalents) from OSS estimated following Intergovernmental Panel for Climate Change (IPCC) guidelines were found to be seven times lower (90.99 g CO2e/cap/day) than in-situ field emission measurements (704.7 g CO2e/cap/day), implying that relying solely on IPCC guidelines may lead to underestimation of GHG emission from OSS. Our findings underscore the importance of considering local contexts and environmental factors when estimating GHG emissions from OSS. Plausible mitigation measures for GHG emissions from OSS include converting waste to biogas in anaerobic systems (e.g. biogas), applying biochar, and implementing mitigation policies that equally address inequalities in sanitation service access. Future research on GHG from OSS should focus on in-situ measurements of GHGs from pit latrines and other common OSS in developing countries, understanding the fate and transport of dissolved organics like CH4 in OSS effluents and impacts of microbial communities in OSS on GHG emissions. Addressing these gaps will enable more holistic and effective management of GHG emissions from OSS.


Asunto(s)
Gases de Efecto Invernadero , Gases de Efecto Invernadero/análisis , Dióxido de Carbono/análisis , Biocombustibles/análisis , Saneamiento , Suelo/química , Metano/análisis , Óxido Nitroso/metabolismo , Efecto Invernadero
19.
J Environ Manage ; 357: 120841, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38581898

RESUMEN

Quercus gilva, an evergreen tree species in Quercus section Cyclobalanopsis, is an ecologically and economically valuable species in subtropical regions of East Asia. Predicting the impact of climate change on potential distribution of Q. gilva can provide a scientific basis for the conservation and utilization of its genetic resources, as well as for afforestation. In this study, 74 distribution records of Q. gilva and nine climate variables were obtained after data collection and processing. Current climate data downloaded from WorldClim and future climate data predicted by four future climate scenarios (2040s SSP1-2.6, 2040s SSP5-8.5, 2060s SSP1-2.6, and 2060s SSP5-8.5) mainly based on greenhouse gases emissions of distribution sites were used in MaxEnt model with optimized parameters to predict distribution dynamics of Q. gilva and its response to climate change. The results showed that the predicted current distribution was consistent with natural distribution of Q. gilva, which was mainly located in Hunan, Jiangxi, Zhejiang, Fujian, Guizhou, and Taiwan provinces of China, as well as Japan and Jeju Island of South Korea. Under current climate conditions, precipitation factors played a more significant role than temperature factors on distribution of Q. gilva, and precipitation of driest quarter (BIO17) is the most important restriction factor for its current distribution (contribution rate of 57.35%). Under future climate conditions, mean temperature of driest quarter (BIO9) was the essential climate factor affecting future change in potential distribution of Q. gilva. As the degree of climatic anomaly increased in the future, the total area of predicted distribution of Q. gilva showed a shrinking trend (decreased by 12.24%-45.21%) and Q. gilva would migrate to high altitudes and latitudes. The research results illustrated potential distribution range and suitable climate conditions of Q. gilva, which can provide essential theoretical references for the conservation, development, and utilization of Q. gilva and other related species.


Asunto(s)
Gases de Efecto Invernadero , Quercus , Cambio Climático , China , Taiwán , Ecosistema
20.
PLoS One ; 19(4): e0297784, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38603686

RESUMEN

Based on the integrated model of Super-SBM model, spatial Durbin model (SDM) and Grey neural network model, this paper analyzes the panel data of various provinces in China from multiple angles and dimensions. It was found that there were significant differences in eco-efficiency between organic rice production and conventional rice production. The response of organic rice to climate change, the spatial distribution of ecological and economic benefits and the impact on carbon emission were analyzed. The results showed that organic rice planting not only had higher economic benefits, but also showed a rising trend of ecological benefits and a positive feedback effect. This finding highlights the importance of organic rice farming in reducing carbon emissions. Organic rice farming effectively reduces greenhouse gas emissions, especially carbon dioxide and methane, by improving soil management and reducing the use of fertilizers and pesticides. This has important implications for mitigating climate change and promoting soil health and biodiversity. With the acceleration of urbanization, the increase of organic rice planting area shows the trend of organic rice gradually replacing traditional rice cultivation, further highlighting the potential of organic agriculture in emission reduction, environmental protection and sustainable agricultural production. To this end, it is recommended that the Government implement a diversified support strategy to encourage technological innovation, provide guidance and training, and raise public awareness and demand for organic products. At the same time, private sector participation is stimulated to support the development of organic rice cultivation through a public-private partnership model. Through these measures, further promote organic rice cultivation, achieve the dual goals of economic benefits and environmental benefits, and effectively promote the realization of double carbon emission reduction targets.


Asunto(s)
Gases de Efecto Invernadero , Oryza , Agricultura/métodos , Suelo , Agricultura Orgánica , China , Metano/análisis , Fertilizantes
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