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1.
Proc Natl Acad Sci U S A ; 120(43): e2304826120, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37844251

RESUMO

Future food farming technology faces challenges that must integrate the core goal of keeping the global temperature increase within 1.5 °C without reducing food security and nutrition. Here, we show that boosting the production of insects and earthworms based on food waste and livestock manure to provide food and feed in China will greatly contribute to meeting the country's food security and carbon neutrality pledges. By substituting domestic products with mini-livestock (defined as earthworms and insects produced for food or feed) protein and utilizing the recovered land for bioenergy production plus carbon capture and storage, China's agricultural sector could become carbon-neutral and reduce feed protein imports to near zero. This structural change may lead to reducing greenhouse gas emissions by 2,350 Tg CO2eq per year globally when both domestic and imported products are substituted. Overall, the success of mini-livestock protein production in achieving carbon neutrality and food security for China and its major trading partners depends on how the substitution strategies will be implemented and how the recovered agricultural land will be managed, e.g., free use for afforestation and bioenergy or by restricting this land to food crop use. Using China as an example, this study also demonstrates the potential of mini-livestock for decreasing the environmental burden of food production in general.


Assuntos
Gado , Eliminação de Resíduos , Animais , Efeito Estufa , Alimentos , Carbono , Biodiversidade , Temperatura , Agricultura , Segurança Alimentar , China
2.
J Anim Ecol ; 93(4): 393-405, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38100230

RESUMO

Comprehending symbiont abundance among host species is a major ecological endeavour, and the metabolic theory of ecology has been proposed to understand what constrains symbiont populations. We parameterized metabolic theory equations to investigate how bird species' body size and the body size of their feather mites relate to mite abundance according to four potential energy (uropygial gland size) and space constraints (wing area, total length of barbs and number of feather barbs). Predictions were compared with the empirical scaling of feather mite abundance across 106 passerine bird species (26,604 individual birds sampled), using phylogenetic modelling and quantile regression. Feather mite abundance was strongly constrained by host space (number of feather barbs) but not by energy. Moreover, feather mite species' body size was unrelated to the body size of their host species. We discuss the implications of our results for our understanding of the bird-feather mite system and for symbiont abundance in general.


Assuntos
Doenças das Aves , Infestações por Ácaros , Ácaros , Passeriformes , Animais , Filogenia , Tamanho Corporal , Infestações por Ácaros/veterinária
3.
J Environ Manage ; 337: 117732, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36944291

RESUMO

Ammonia (NH3) volatilization, nitrous oxide (N2O) emissions, and nitrate (NO3-) leaching from agriculture cause severe environmental hazards. Research studies and mitigation strategies have mostly focused on one of these nitrogen (N) losses at a time, often without an integrated view of the agro-food system. Yet, at the regional scale, N2O, NH3, and NO3- loss patterns reflect the structure of the whole agro-food system. Here, we analyzed at the resolution of NUTS2 administrative European Union (EU) regions, N fluxes through the agro-food systems of a Temperate-Mediterranean gradient (France, Spain, and Portugal) experiencing contrasting climate and soil conditions. We assessed the atmospheric and hydrological N emissions from soils and livestock systems. Expressed per ha agricultural land, NH3 volatilization varied in the range 6.2-44.4 kg N ha-1 yr-1, N2O emission and NO3 leaching 0.3-4.9 kg N ha-1 yr-1 and 5.4-154 kg N ha-1 yr-1 respectively. Overall, lowest N2O emission was found in the Mediterranean regions, where NO3- leaching was greater. NH3 volatilization in both temperate and Mediterranean regions roughly follows the distribution of livestock density. We showed that these losses are also closely correlated with the level of fertilization intensity and agriculture system specialization into either stockless crop farming or intensive livestock farming in each region. Moreover, we explored two possible future scenarios at the 2050 horizon: (1) a scenario based on the prescriptions of the EU-Farm-to-Fork (F2F) strategy, with 25% of organic farming, 10% of land set aside for biodiversity, 20% reduction in N fertilizers, and no diet change; and (2) a hypothetical agro-ecological (AE) scenario with generalized organic farming, reconnection of crop and livestock farming, and a healthier human diet with an increase in the share of vegetal protein to 65% (i.e., the Mediterranean diet). Results showed that the AE scenario, owing to its profound reconfiguration of the entire agro-food system would have the potential for much greater reductions in NH3, N2O, and NO3- emissions, namely, 60-81% reduction, while the F2F scenario would only reach 24-35% reduction of N losses.


Assuntos
Agricultura , Nitrogênio , Humanos , Nitrogênio/análise , Agricultura/métodos , Solo/química , Amônia/análise , Fazendas , Fertilizantes , Óxido Nitroso/análise
4.
Agron Sustain Dev ; 43(6): 75, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37969112

RESUMO

Early energy analyses of agriculture revealed that behind higher labor and land productivity of industrial farming, there was a decrease in energy returns on energy (EROI) invested, in comparison to more traditional organic agricultural systems. Studies on recent trends show that efficiency gains in production and use of inputs have again somewhat improved energy returns. However, most of these agricultural energy studies have focused only on external inputs at the crop level, concealing the important role of internal biomass flows that livestock and forestry recirculate within agroecosystems. Here, we synthesize the results of 82 farm systems in North America and Europe from 1830 to 2012 that for the first time show the changing energy profiles of agroecosystems, including livestock and forestry, with a multi-EROI approach that accounts for the energy returns on external inputs, on internal biomass reuses, and on all inputs invested. With this historical circular bioeconomic approach, we found a general trend towards much lower external returns, little or no increases in internal returns, and almost no improvement in total returns. This "energy trap" was driven by shifts towards a growing dependence of crop production on fossil-fueled external inputs, much more intensive livestock production based on feed grains, less forestry, and a structural disintegration of agroecosystem components by increasingly linear industrial farm managements. We conclude that overcoming the energy trap requires nature-based solutions to reduce current dependence on fossil-fueled external industrial inputs and increase the circularity and complexity of agroecosystems to provide healthier diets with less animal products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-023-00925-5.

5.
J Environ Manage ; 288: 112304, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33773210

RESUMO

Enhanced-efficiency nitrogen (N) fertilizers, such as those containing nitrification or urease inhibitors, can mitigate the carbon (C) footprint linked to the production of bioenergy crops through a reduction in direct nitrous oxide (N2O) emissions and indirect N2O losses. These indirect emissions are derived from ammonia (NH3) volatilization, which also have important environmental and health implications. The evaluation of the global warming potential (GWP) of different N sources using site-specific data of yield and direct and indirect emissions is needed for oilseed rape under rainfed semi-arid conditions, especially when meteorological variability is taken into account. Using urea as a N source, the N2O mitigation efficacy of the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) alone or combined with the nitrification inhibitor 2-(3,4-dimethyl-1H-pyrazol-1-yl) succinic acid isomeric mixture (DMPSA) was evaluated under field conditions in a rainfed oilseed rape (Brassica napus L.) crop. Two additional N sources from calcium ammonium nitrate (CAN), with and without DMPSA, were included. The GWP of the treatments was estimated considering the emissions from inputs, operations and other direct and indirect emissions of greenhouse gases (GHGs), such as methane (CH4) and the volatilization of NH3. We also measured the abundance of key genes involved in nitrification and denitrification to improve the understanding of N2O emissions on a biochemical basis under the conditions of our study. The results show that due to the intense rainfall after fertilization and a rewetting event, N2O losses from fertilizers without inhibitors were greater than those previously reported under Mediterranean conditions, while NH3 losses were low and not affected by the urease inhibitor. The cumulative N2O emissions (which were greatly influenced by a rewetting peak three months after fertilization) from the urea fertilization were significantly higher than those from CAN. The presence of NBPT significantly reduced N2O losses by an average of 71%, with respect to urea. The use of DMPSA with CAN resulted in an abatement of N2O emissions (by 57%) and a significant increase in oil yield in comparison with CAN alone. All inhibitor-based treatments were effective in abating N2O emissions during the rewetting peak. The abundances of the nitrifier and denitrifier communities, especially ammonia-oxidizing bacteria (AOB), significantly decreased relative to the urea or CAN treatments as inhibitors were applied. Under the conditions of our study, the sustainability of a bioenergy crop such as oilseed rape can be improved by using inhibitors because they mitigated N2O emissions and/or enhanced the oil yield.


Assuntos
Brassica napus , Óxido Nitroso , Agricultura , Fertilizantes/análise , Aquecimento Global , Óxido Nitroso/análise , Solo
6.
Glob Chang Biol ; 26(7): 4158-4168, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32412147

RESUMO

This study evaluates the dynamics of soil organic carbon (SOC) under perennial crops across the globe. It quantifies the effect of change from annual to perennial crops and the subsequent temporal changes in SOC stocks during the perennial crop cycle. It also presents an empirical model to estimate changes in the SOC content under crops as a function of time, land use, and site characteristics. We used a harmonized global dataset containing paired-comparison empirical values of SOC and different types of perennial crops (perennial grasses, palms, and woody plants) with different end uses: bioenergy, food, other bio-products, and short rotation coppice. Salient outcomes include: a 20-year period encompassing a change from annual to perennial crops led to an average 20% increase in SOC at 0-30 cm (6.0 ± 4.6 Mg/ha gain) and a total 10% increase over the 0-100 cm soil profile (5.7 ± 10.9 Mg/ha). A change from natural pasture to perennial crop decreased SOC stocks by 1% over 0-30 cm (-2.5 ± 4.2 Mg/ha) and 10% over 0-100 cm (-13.6 ± 8.9 Mg/ha). The effect of a land use change from forest to perennial crops did not show significant impacts, probably due to the limited number of plots; but the data indicated that while a 2% increase in SOC was observed at 0-30 cm (16.81 ± 55.1 Mg/ha), a decrease in 24% was observed at 30-100 cm (-40.1 ± 16.8 Mg/ha). Perennial crops generally accumulate SOC through time, especially woody crops; and temperature was the main driver explaining differences in SOC dynamics, followed by crop age, soil bulk density, clay content, and depth. We present empirical evidence showing that the FAO perennialization strategy is reasonable, underscoring the role of perennial crops as a useful component of climate change mitigation strategies.


Assuntos
Carbono , Solo , Agricultura , Sequestro de Carbono , Produtos Agrícolas
7.
Environ Sci Technol ; 53(9): 5091-5101, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30939241

RESUMO

Irrigation in the Mediterranean region has been used for millennia and has greatly expanded with industrialization. Irrigation is critical for climate change adaptation, but it is also an important source of greenhouse gas emissions. This study analyzes the carbon (C) footprint of irrigation in Spain, covering the complete historical process of mechanization. A 21-fold total, 6-fold area-based, and 4-fold product-based increase in the carbon footprint was observed during the 20th century, despite an increase in water use efficiency. CH4 emissions from waterbodies, which had not previously been considered in the C footprint of irrigation systems, dominated the emission budget during most of the analyzed period. Technologies to save water and tap new water resources greatly increased energy and infrastructure demand, while improvements in power generation efficiency had a limited influence on irrigation emissions. Electricity production from irrigation dams may contribute to climate change mitigation, but the amount produced in relation to that consumed in irrigation has greatly declined. High uncertainty in CH4 emission estimates from waterbodies stresses a need for more spatially resolved data and an improved empirical knowledge of the links between water quality, water level fluctuations, and emissions at the regional scale.


Assuntos
Pegada de Carbono , Gases de Efeito Estufa , Metano , Espanha , Água
8.
Reg Environ Change ; 18(4): 1089-1101, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31258413

RESUMO

Energy efficiency in biomass production is a major challenge for a future transition to sustainable food and energy provision. This study uses methodologically consistent data on agroecosystem energy flows and different metrics of energetic efficiency from seven regional case studies in North America (USA and Canada) and Europe (Spain and Austria) to investigate energy transitions in Western agroecosystems from the late nineteenth to the late twentieth centuries. We quantify indicators such as external final energy return on investment (EFEROI, i.e., final produce per unit of external energy input), internal final EROI (IFEROI, final produce per unit of biomass reused locally), and final EROI (FEROI, final produce per unit of total inputs consumed). The transition is characterized by increasing final produce accompanied by increasing external energy inputs and stable local biomass reused. External inputs did not replace internal biomass reinvestments, but added to them. The results were declining EFEROI, stable or increasing IFEROI, and diverging trends in FEROI. The factors shaping agroecosystem energy profiles changed in the course of the transition: Under advanced organic and frontier agriculture of the late nineteenth and early twentieth centuries, population density and biogeographic conditions explained both agroecosystem productivity and energy inputs. In industrialized agroecosystems, biogeographic conditions and specific socio-economic factors influenced trends towards increased agroecosystem specialization. The share of livestock products in a region's final produce was the most important factor determining energy returns on investment.

9.
Glob Chang Biol ; 21(3): 1313-27, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25393229

RESUMO

The establishment of sustainable soil waste management practices implies minimizing their environmental losses associated with climate change (greenhouse gases: GHGs) and ecosystems acidification (ammonia: NH3 ). Although a number of management strategies for solid waste management have been investigated to quantify nitrogen (N) and carbon (C) losses in relation to varied environmental and operational conditions, their overall effect is still uncertain. In this context, we have analyzed the current scientific information through a systematic review. We quantified the response of GHG emissions, NH3 emissions, and total N losses to different solid waste management strategies (conventional solid storage, turned composting, forced aerated composting, covering, compaction, addition/substitution of bulking agents and the use of additives). Our study is based on a meta-analysis of 50 research articles involving 304 observations. Our results indicated that improving the structure of the pile (waste or manure heap) via addition or substitution of certain bulking agents significantly reduced nitrous oxide (N2 O) and methane (CH4 ) emissions by 53% and 71%, respectively. Turned composting systems, unlike forced aerated composted systems, showed potential for reducing GHGs (N2 O: 50% and CH4 : 71%). Bulking agents and both composting systems involved a certain degree of pollution swapping as they significantly promoted NH3 emissions by 35%, 54%, and 121% for bulking agents, turned and forced aerated composting, respectively. Strategies based on the restriction of O2 supply, such as covering or compaction, did not show significant effects on reducing GHGs but substantially decreased NH3 emissions by 61% and 54% for covering and compaction, respectively. The use of specific additives significantly reduced NH3 losses by 69%. Our meta-analysis suggested that there is enough evidence to refine future Intergovernmental Panel on Climate Change (IPCC) methodologies from solid waste, especially for solid waste composting practices. More holistic and integrated approaches are therefore required to develop more sustainable solid waste management systems.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Nitrogênio/análise , Gerenciamento de Resíduos , Gases/análise , Efeito Estufa , Resíduos Sólidos/análise
10.
J Environ Manage ; 153: 48-9, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25646676

RESUMO

Sommer and Bossio (2014) model the potential soil organic carbon (SOC) sequestration in agricultural soils (croplands and grasslands) during the next 87 years, concluding that this process cannot be considered as a climate stabilization wedge. We argue, however, that the amounts of SOC potentially sequestered in both scenarios (pessimistic and optimistic) fulfil the requirements for being considered as wedge because in both cases at least 25 GtC would be sequestered during the next 50 years. We consider that it is precisely in the near future, and meanwhile other solutions are developed, when this stabilization effort is most urgent even if after some decades the sequestration rate is significantly reduced. Indirect effects of SOC sequestration on mitigation could reinforce the potential of this solution. We conclude that the sequestration of organic carbon in agricultural soils as a climate change mitigation tool still deserves important attention for scientists, managers and policy makers.


Assuntos
Agricultura , Carbono/análise , Mudança Climática , Solo/química
11.
Environ Pollut ; 341: 122814, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37898427

RESUMO

Ammonia (NH3) volatilization is the major source of nitrogen (N) loss resulting from the application of synthetic and organic N fertilizers to croplands. It is well known that in Mediterranean cropping systems, there is a relationship between the intrinsic characteristics of the climate and nitrous oxide (N2O) emissions, but whether the same relation exists for NH3 emissions remains uncertain. Here, we estimated the impact of edaphoclimatic conditions (including meteorological conditions after N fertilization), crop management factors, and the measurement technique on both the cumulative emissions and the NH3 emission factor (EF) in Mediterranean climate zones, drawing on a database of 234 field treatments. We used a machine learning method, random forest (RF), to predict volatilization and ranked variables based on their importance in the prediction. Random forest had a good predictive power for the NH3 EF and cumulative emissions, with an R2 of 0.69 and 0.76, respectively. Nitrogen fertilization rate (N rate) was the top-ranked predictor variable, increasing NH3 emissions substantially when N rate was higher than 170 kg N ha-1. Soil pH was the most important edaphoclimatic variable, showing greater emissions (36.7 kg NH3 ha-1, EF = 19.3%) when pH was above 8.2. Crop type, fertilizer type, and N application method also affected NH3 emission patterns, while water management, mean precipitation, and soil texture were ranked low by the model. Our results show that intrinsic Mediterranean characteristics had only an indirect effect on NH3 emissions. For instance, relatively low N fertilization rates result in small NH3 emissions in rainfed areas, which occupy a very significant surface of Mediterranean agricultural land. Overall, N fertilization management is a key driver in reducing NH3 emissions, but additional field factors should be studied in future research to establish more robust abatement strategies.


Assuntos
Agricultura , Amônia , Amônia/análise , Volatilização , Solo , Nitrogênio/análise , Fertilizantes/análise , Óxido Nitroso/análise
12.
Sci Total Environ ; 892: 164467, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37268115

RESUMO

Along its route through the agro-food system nitrogen (N) can be wasted, heightening diverse environmental problems. Geopolitical instabilities affect prices of N fertilisers and livestock feed, challenging production systems and increasing their need to reduce N waste. The analysis of N flows is essential to understanding the agroenvironmental performance of agro-food systems to detect leakages and to design strategies for reducing N pollution while producing feed and food. Sectorial analyses can mislead conclusions, prompting the need for integrated approaches. We present a multiscale analysis of N flows for the 1990-2015 period to identify both the strengths and weaknesses of the Spanish agro-food system. We constructed N budgets at three system scales, namely crop, livestock and the agro-food system, and at two spatial scales: national and regional (50 provinces). The big picture shows a country with increasing crop (575 to 634 GgN/yr) and livestock (138 to 202 GgN/yr, edible) production and nitrogen use efficiency improvements, especially for certain crop and livestock categories. Nevertheless, this falls short of reducing agricultural surpluses (812 GgN/yr) and external dependency, which is closely related to the externalisation of certain environmental impacts (system NUE, from 31 % to 19 % considering externalisation). The regional picture shows the contrasted operation between provinces, assigned to three agro-food system categories: fuelled by synthetic fertiliser (29 provinces), grassland inputs to livestock (5 provinces) or the net import of feed (16 provinces). Regional specialisation on crop or livestock production was reinforced, hampering good recirculation of N through livestock feed from regional cropland and their N fertilisation by regional livestock excretion. We conclude that pollution and external dependency need to be further reduced in Spain. To do so, the big picture of the full system is paramount but must be adapted to the regional particularities.


Assuntos
Agricultura , Nitrogênio , Animais , Meio Ambiente , Alimentos , Poluição Ambiental , Gado , Fertilizantes
13.
Sci Total Environ ; 889: 164249, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37209724

RESUMO

Irrigation, one of the 28 agri-environmental indicators defined in the European Common Agricultural Policy, is often neglected in agricultural nitrogen (N) budgets, while it can be a considerable source of N in irrigated agriculture. The annual N input from irrigation water sources (NIrrig) to cropping systems was quantified for Europe for 2000-2010 at a resolution of 10 × 10 km, accounting for crop-specific gross irrigation requirements (GIR) and surface- and groundwater nitrate concentration. GIR were computed for 20 crops, while spatially explicit nitrate concentration in groundwater was derived using a random forest model. We show that although GIR were relatively stable (46-60 km3 yr-1), the Nirrig in Europe increased over the 10-year period (184 to 259 Gg N yr-1), approximately 68 % of which occurred in the Mediterranean region. The main hotspots appeared in areas with both high irrigation requirements and high groundwater nitrate concentration, reaching up to averaged values of 150 kg N ha-1 yr1. These were mainly located in Mediterranean Europe (Greece, Portugal and Spain) and to a lesser extent in Northern Europe (The Netherlands, Sweden and Germany). By not including NIrrig, environmental and agricultural policies are underestimating the real extent of N pollution hotspots in European irrigated systems.


Assuntos
Água Subterrânea , Nitrogênio , Nitrogênio/análise , Nitratos/análise , Agricultura , Europa (Continente) , Ciclo do Nitrogênio , Irrigação Agrícola
14.
J Anim Ecol ; 81(5): 1113-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22372885

RESUMO

1. Understanding the impact of environmental variability on migrating species requires the estimation of sequential abiotic effects in different geographic areas across the life cycle. For instance, waterfowl (ducks, geese and swans) usually breed widely dispersed throughout their breeding range and gather in large numbers in their wintering headquarters, but there is a lack of knowledge on the effects of the sequential environmental conditions experienced by migrating birds on the long-term community dynamics at their wintering sites. 2. Here, we analyse multidecadal time-series data of 10 waterfowl species wintering in the Guadalquivir Marshes (SW Spain), the single most important wintering site for waterfowl breeding in Europe. We use a multivariate state-space approach to estimate the effects of biotic interactions, local environmental forcing during winter and large-scale climate during breeding and migration on wintering multispecies abundance fluctuations, while accounting for partial observability (observation error and missing data) in both population and environmental data. 3. The joint effect of local weather and large-scale climate explained 31·6% of variance at the community level, while the variability explained by interspecific interactions was negligible (<5%). In general, abiotic conditions during winter prevailed over conditions experienced during breeding and migration. Across species, a pervasive and coherent nonlinear signal of environmental variability on population dynamics suggests weaker forcing at extreme values of abiotic variables. 4. Modelling missing observations through data augmentation increased the estimated magnitude of environmental forcing by an average 30·1% and reduced the impact of stochasticity by 39·3% when accounting for observation error. Interestingly however, the impact of environmental forcing on community dynamics was underestimated by an average 15·3% and environmental stochasticity overestimated by 14·1% when ignoring both observation error and data augmentation. 5. These results provide a salient example of sequential multiscale environmental forcing in a major migratory bird community, which suggests a demographic link between the breeding and wintering grounds operating through nonlinear environmental effects. Remarkably, this study highlights that modelling observation error in the environmental covariates of an ecological model can be proportionally more important than modelling this source of variance in the population data.


Assuntos
Migração Animal/fisiologia , Anseriformes/classificação , Anseriformes/fisiologia , Modelos Biológicos , Processos Estocásticos , Tempo (Meteorologia) , Animais , Ecossistema , Dinâmica Populacional , Fatores de Tempo
15.
Sci Data ; 8(1): 288, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34716345

RESUMO

This paper presents EuropeAgriDB v1.0, a dataset of crop production and nitrogen (N) flows in European cropland 1961-2019. The dataset covers 26 present-day countries, detailing the cropland N harvests in 17 crop categories as well as cropland N inputs in synthetic fertilizers, manure, symbiotic fixation, and atmospheric deposition. The study builds on established methods but goes beyond previous research by combining data from FAOSTAT, Eurostat, and a range of national data sources. The result is a detailed, complete, and consistent dataset, intended as a basis for further analyses of past and present agricultural production patterns, as well as construction of scenarios for the future.


Assuntos
Produção Agrícola , Fertilizantes , Pradaria , Nitrogênio , Europa (Continente) , Nitrogênio/análise
16.
Sci Data ; 6(1): 57, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086193

RESUMO

A global, unified dataset on Soil Organic Carbon (SOC) changes under perennial crops has not existed till now. We present a global, harmonised database on SOC change resulting from perennial crop cultivation. It contains information about 1605 paired-comparison empirical values (some of which are aggregated data) from 180 different peer-reviewed studies, 709 sites, on 58 different perennial crop types, from 32 countries in temperate, tropical and boreal areas; including species used for food, bioenergy and bio-products. The database also contains information on climate, soil characteristics, management and topography. This is the first such global compilation and will act as a baseline for SOC changes in perennial crops. It will be key to supporting global modelling of land use and carbon cycle feedbacks, and supporting agricultural policy development.

17.
Rev Invest Clin ; 60(5): 432-7, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-19227441

RESUMO

The prehispanic medicines of Mexico are considered as testimony of the splendor of the Meso-American cultures; their great scientific advance and technical allowed them to accumulate a vast collection of clinical and pathological data based on the observation and experimentation. They integrated a nomenclature medical surgical that reflected their advance in those fields of the knowledge, where the anatomy and surgery occupied a preponderant paper. The medicine was known generically as ticiotl, of where it derives the term tícitl for the doctor. In their concept health-illness the limits among the magic, religion and the empiricism for natural causes were not clear, therefore they considered that the divine, human or natural origin of the illnesses influenced in an important way in its nature. Inside this complex causal system, the illnesses caused by the gods, spirits and celestial beings were considered as hot, while those caused by beings of the other realm were cold. The practice of the medicine had a very established organization designing a very advanced system of specialties that allowed them to accumulate a vast experience for the handling of chronic and acute illnesses in different progression phases, which managed with an integral therapy that had a plurality of resources of vegetable origin, animal, and mineral. The surgery was designated as texoxotlaliztli and its cures tepatiliztli. The surgeon was designated as texoxotlaticitl and it developed advanced techniques in the handling of sutures, wounded, drainage of abscesses, fractures and joint dislocations, pterygium, tonsillitis, circumcision, and amputations.


Assuntos
Cirurgia Geral/história , Medicina Tradicional/história , Feminino , História do Século XVI , História Antiga , Humanos , Indígenas Norte-Americanos/história , Magia/história , Masculino , México , Fitoterapia/história , Religião e Medicina , Ferimentos e Lesões/história , Ferimentos e Lesões/cirurgia , Ferimentos e Lesões/terapia
18.
Sci Total Environ ; 621: 634-648, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29202285

RESUMO

Soil organic carbon (SOC) management is key for soil fertility and for mitigation and adaptation to climate change, particularly in desertification-prone areas such as Mediterranean croplands. Industrialization and global change processes affect SOC dynamics in multiple, often opposing, ways. Here we present a detailed SOC balance in Spanish cropland from 1900 to 2008, as a model of a Mediterranean, industrialized agriculture. Net Primary Productivity (NPP) and soil C inputs were estimated based on yield and management data. Changes in SOC stocks were modeled using HSOC, a simple model with one inert and two active C pools, which combines RothC model parameters with humification coefficients. Crop yields increased by 227% during the studied period, but total C exported from the agroecosystem only increased by 73%, total NPP by 30%, and soil C inputs by 20%. There was a continued decline in SOC during the 20th century, and cropland SOC levels in 2008 were 17% below their 1933 peak. SOC trends were driven by historical changes in land uses, management practices and climate. Cropland expansion was the main driver of SOC loss until mid-20th century, followed by the decline in soil C inputs during the fast agricultural industrialization starting in the 1950s, which reduced harvest indices and weed biomass production, particularly in woody cropping systems. C inputs started recovering in the 1980s, mainly through increasing crop residue return. The upward trend in SOC mineralization rates was an increasingly important driver of SOC losses, triggered by irrigation expansion, soil cover loss and climate change-driven temperature rise.

19.
Cir Cir ; 85(3): 254-259, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-27260218

RESUMO

BACKGROUND: The first reported case of intestinal perforation secondary to metastatic lung carcinoma was reported in 1957. Intestinal metastases are present in up to 1.8% of the cases, with small bowel obstruction as the most common clinical presentation. CLINICAL CASE: An 89 year-old male, who was diagnosed with a high-grade pulmonary mucoepidermoid tumour 2 months previously. The patient was admitted to the hospital for 3 days due to diffuse colic abdominal pain of moderate to severe intensity, accompanied by nausea and gastric vomiting, as well as 2 episodes of bloody bowel movements. On physical examination, the patient was noted to have tachycardia and tachypnoea, as well as clinical signs of acute abdomen. He had white cells of 24,900 per mm3, and 87% neutrophils. Exploratory laparotomy was performed, which showed a bowel perforation associated with a tumour mass 15cm beyond the angle of Treitz. Bowel resection and primary anastomosis were performed. The histopathological analysis reported the diagnosis of a high-grade mucoepidermoid tumour with small bowel and mesentery with disease-free surgical margins. Unfortunately the patient had a fatal outcome secondary to hospital-acquired pneumonia. CONCLUSION: The cases of metastases to small bowel are extremely rare, and to our knowledge this is first case reported in Mexico. The patient described went to the emergency room with gastrointestinal bleed and intestinal perforation that required urgent surgical intervention with small bowel resection and primary anastomosis. Unfortunately the patient died secondary to hospital acquired pneumonia.


Assuntos
Carcinoma Mucoepidermoide/secundário , Perfuração Intestinal/etiologia , Doenças do Jejuno/etiologia , Neoplasias do Jejuno/secundário , Neoplasias Pulmonares/patologia , Abdome Agudo/etiologia , Idoso de 80 Anos ou mais , Carcinoma Mucoepidermoide/complicações , Carcinoma Mucoepidermoide/diagnóstico por imagem , Infecção Hospitalar/etiologia , Evolução Fatal , Humanos , Perfuração Intestinal/diagnóstico por imagem , Doenças do Jejuno/diagnóstico por imagem , Neoplasias do Jejuno/complicações , Neoplasias do Jejuno/diagnóstico por imagem , Masculino , Pneumonia/etiologia , Complicações Pós-Operatórias/etiologia , Tomografia Computadorizada por Raios X
20.
Cancer Biother Radiopharm ; 32(2): 49-56, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28301259

RESUMO

Recent successes in the development of new therapies for metastatic melanoma, such as mitogen-activated protein kinase pathway inhibitors, anticytotoxic T lymphocyte-associated antigen-4, and programmed cell death protein 1/programmed cell death ligand 1 (PD-L1) pathway-blocking antibodies, as well as combination strategies, all yielded promising results, changing the continually evolving landscape of therapeutic options for patients with melanoma. One promising new treatment modality is based on the use of immunomodulatory monoclonal antibodies that enhance the function of components of the antitumor immune response such as T cells or block immunologic checkpoints that restrain effective antitumor immunity. Program death-1 receptor and its ligand, PD-L1, is a major mechanism by which a tumor suppresses T cell-mediated antitumor immune responses. Studies in mice have shown that GK-1, an 18 amino acid peptide from Taenia crassiceps cisticerci, has the potential to be used as a primary or adjuvant component for the treatment of cancers by stimulating proinflammatory cytokines. The authors hypothesized that treatment with GK-1 in combination with anti-PD-L1 will increase survival in mice bearing melanoma tumors. C57BL/6 mice were injected with B16-F10-luc2 cells and separated into four groups: control, GK-1, anti-PD-L1, and GK-1/anti-PD-L1. The tumor sizes were measured and monitored using calipers and bioluminescence. The GK-1 peptide in combination with anti-PD-L1 showed significantly longer survival (34 days) compared with the other groups (23-27 days). This means an increase; survival increased 47.82% in the mice treated with GK-1+anti-PD-L1, 21.7% in mice treated with GK-1 alone, and 6.08% in those mice treated with anti-PD-L1 only. Blood samples were collected at days 0, 14, and at euthanization or end of the experiment and monitored for cytokines using mouse-specific V-PLEX Proinflammatory Panel. A decrease in TNF-α, IL-4, IL-5, IL-6, and IL-10 serum levels was observed in the GK-1/anti-PD-L1 combination group that may explain the beneficial effects of the combination treatment in prolonging the life of mice bearing melanoma. The data indicate that GK-1/anti-PD-L1 combined therapy affectively increases survival and warrants further clinical investigations.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Melanoma/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Animais , Linhagem Celular Tumoral , Citocinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Imunoterapia/métodos , Inflamação , Luminescência , Masculino , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Peptídeos/uso terapêutico , Modelos de Riscos Proporcionais , Taenia
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