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1.
Huan Jing Ke Xue ; 43(1): 442-453, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989529

RESUMO

In order to ascertain the impact of pyrite mining on the surrounding farmland soil environment and human health, 42 surface soil samples (from 0-20 cm) were collected around the pyrite mining area in Longyou county. In this study, the concentrations of eight heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) and the pH in the topsoil were analyzed, and the concentration characteristics of heavy metals, source analysis, and human health risks assessment were studied using statistical analysis (SA), geo-accumulation index (Igeo), positive matrix factorization (PMF), and the health risk model. The average of ω(Cd), ω(Cu), ω(Pb), and ω(Zn) concentrations exceeded the background values of soils in Zhejiang province and China. According to the agricultural land pollution risk screening values (GB 15618-2018), Cd, Cu, Pb, and Zn were up to 82%, 49%, 42%, and 31%, respectively. The Igeo shows that the major pollutant element in the soils was Cd, followed by Cu, Pb, and Zn. The PMF analysis indicates that nature sources (As, Cr, and Ni), comprehensive pollution sources caused by high geological background and mining of ore-forming geological bodies (Cd, Cu, Pb, and Zn), and anthropogenic sources (Hg) were the three major sources of heavy metals in the study area, with contributions of 32%, 46%, and 22%, respectively. The results of the health risk assessment indicate that the major non-carcinogenic factor triggering risks was the ingestion of Pb; Cr exposure had carcinogenic risk for adults, and Cr and As exposure had carcinogenic risk for children.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , China , Monitoramento Ambiental , Fazendas , Humanos , Ferro , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Sulfetos
2.
Huan Jing Ke Xue ; 43(1): 454-462, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989530

RESUMO

Agricultural products are a primary pathway for humans to accumulate heavy metals (HMs) via the soil-crop system and should therefore should be included as a crucial part of the food security in our country. Given that previous studies on protection zoning for preventing farmland HM pollution rarely considered agricultural products as a basic element, this study attempted to establish a zoning system for farmland HM prevention, which was based on the perspective of agricultural product pollution. We subsequently took a representative peri-urban area in the black soil region, which was provided with a higher risk of being polluted, as an empirical case. The results indicated that:① the comprehensive quality index of agricultural products (IICQAP) was 1.09, illustrating only a mild HM pollution, with Pb and Ni having the highest accumulation levels; ② the human health risk index (QHI) was 0.61, showing no risk for human health; and ③ the designed zoning method revealed 89.45% of the farmlands to be risk-free at the moment and 10.55% of the farmlands to be under low risk of HM pollution in agricultural products. According to the zoning results, we suggested prioritized protection and an early-warning strategy, respectively, and further recommended prevention methods such as accumulation intervention, crop restructuring, and in-situ passivation. The results served to enrich the theoretical basis for preventing farmland HM pollution, to reinforce the management standards for agricultural products in the black soil region, and also to build a differentiated urban-rural farmland protection system.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Fazendas , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
3.
J Environ Manage ; 304: 114300, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35021590

RESUMO

Payment for Ecosystem Services (PES) has been widely accepted as a policy tool for promoting ecological and social progress. However, PES development and implementation in traditional agricultural and pastoral areas are often more challenging than in other areas. The contradiction between ecological protection and people's livelihood development in traditional agricultural and pastoral areas is related to developing country's sustainable development strategy. Based on this, we evaluate the PES (ERCCP: the Ecological Relocation and Capital Compensation Program) program in Tianzhu County, as a case study to investigated the impact of ERCCP on the local natural and social ecosystems on a 20-year scale. The results of indicated that ERCCP has achieved "win-win" gains of restoring environment and promoting socioeconomic development: in the 10 years since ERCCP was implemented, the area of forest land and grassland increased significantly, increasing by 1135.6 ha and 919.62 ha, respectively. 57.5% of farmland was converted to grassland and 30.8% to forest, respectively. In addition, 92.2% and 7.5% of bare land were replaced by grassland and forest, respectively, indicating a gradual recovery of green land during this period. We also analyzed the effects of ERCCP on social systems, and found that the change of agro-pastoralists' attitude towards ERCCP promoted the transfer of labor force from the primary industry to the tertiary industry, accelerated the development of urbanization, and made the poor population completely out of poverty by 2020. In addition, we predict that the income level of households, the PES return on investment of local governments, and the value of regional ecosystem services will increase significantly after 2025. In this context, We establish a theoretical model to explain the win-win plan for the coordinated development of ecosystem services and regional well-being to explore the sustainability of PES and provided a typical case for the similar research area in the world, especially in the areas with the ecological fragility and poverty problems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Agricultura , China , Fazendas , Florestas , Humanos
4.
Vet Rec ; 190(1): 8, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34994434
5.
Vet Rec ; 190(1): 7, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34994462
6.
Trop Anim Health Prod ; 54(1): 46, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35015157

RESUMO

In mid-2016, the local government of Papua, Indonesia, launched a subsidised program to improve pig farming in the area, with 250 participants. This study aimed to investigate factors associated with enduring participation in pig farming among the program participants. Two years after the commencement of the program, one hundred of the 250 participants were recruited into the study and divided into two groups: participants who continued to engage in pig farming ("remain") and those who had quit pig farming ("quit"). Data were collected from interviews, including personal data and events on the farms between April 2017 and March 2018. Multiple correspondence analysis, followed by a two-step cluster analysis and multivariate regression, was used to explore factors associated with the durability of pig farmings. Results indicated that associated factors included feed and water security, the use of concrete material for the pig house floor, the avoidance of swill feeding, reduced pig mortality, and continued pig husbandry training. This study highlights that a good feeding regimen and effective control of pig diseases should be priority pig husbandry techniques to be extended through training and assistance to improve traditional pig farming in Papua.


Assuntos
Criação de Animais Domésticos , Doenças dos Suínos , Animais , Análise por Conglomerados , Fazendas , Indonésia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controle
7.
Trop Anim Health Prod ; 54(1): 44, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35015158

RESUMO

In order to evaluate the environmental performance generated by a "semi-technified" pig farm, as well as the comparison of different pig production scenarios, pig feed and animal production subsystems were evaluated considering both: (a) origin of feed ingredients and (b) variations in pig weight. Life cycle assessment methodology was used to evaluate the environmental performance, establishing 1 market pig as the functional unit (FU). Three ingredient origin distances (400, 950, and 1800 km) and three slaughter weights (110, 100, and 90 kg) were considered for the simulation analysis and comparison. The feed production subsystem was the main generator of environmental impacts, mainly caused by the cultivation of sorghum and the production of fat. The origin of the inputs represented the main increase in environmental impact for the feed production subsystem, mainly in the Fossil Depletion category, with a fivefold increase by acquiring inputs from 900 km and a ninefold increase at a distance of 1800 km. Producing lighter pigs resulted in the best environmental alternative, given the resultant 11% reduction in environmental impact.


Assuntos
Carne de Porco , Carne Vermelha , Ração Animal/análise , Animais , Meio Ambiente , Fazendas , Estágios do Ciclo de Vida , Suínos
8.
Schweiz Arch Tierheilkd ; 164(1): 25-34, 2022 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-34983737

RESUMO

INTRODUCTION: Toxoplasmosis is a worldwide occurring zoonosis caused by the obligate intracellular parasite Toxoplasma gondii (T. gondii). All warm-blooded species, including humans, serve as intermediate hosts. Definitive hosts are exclusively cats. Farm poultry can become infected with oocysts from contaminated feed or directly from the ground, or by pecking of e.g. infected rodents. Outdoor or free-range housing of poultry increases the risk of infection with length of time. Poulty meat must be seen as a potential source of infection for humans with the increasing popularity of humane animal husbandry practices in poultry farming. This short literature review attempts to assess the current epidemiological situation in farmed poultry and to assess the possible relevance of toxoplasmosis of poultry meat and poultry meat products for human consumption.


Assuntos
Toxoplasma , Toxoplasmose Animal , Animais , Fazendas , Oocistos , Aves Domésticas , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/prevenção & controle
9.
J Environ Manage ; 302(Pt B): 114059, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34773782

RESUMO

We examined the environmental impacts of farmland management practices (FMPs), considering FMPs as frequent or single actions that change both land use AND use rights (land and property relations). Based on a review of the international literature in both the social and life sciences and using an analytical framework of landscape agronomy, we explored the links between FMPs and changes in agricultural practices designed for the achievement of environmental goals. The Web of Science (WOS) and SCOPUS bibliographic databases were used to identify references on FMP types and their environmental effects based on the following search equations: 1- " Farmland tenure OR cropland tenure OR farm size and environment " and 2- "Farmland use rights OR farmland property rights AND environment OR pollution OR biodiversity." Ninety references were selected from these databases and read in depth. Google scholar enabled us to identify an additional 20 papers, using the snowball approach. From this analysis, we present a typology of FMPs based on the distinction between bottom-up strategies, which rely on local initiatives from farmers to improve the overall functioning of their farms, and top-down strategies, which originate from public bodies or private organizations. Our results also highlight the environmental impacts of FMPs considered in the literature: tenure arrangements, whether rental or exchange of land parcels, may alter crop succession and reduce phytosanitary pressure without changing cropping plans. Considering the direct agronomic implications of farmers' land dynamics, we conclude that the area of FMPs is a potential tool for reducing the environmental impacts of agricultural activities and protecting natural resources. This is the subject of ongoing research that seeks to explore a particular FMP in greater depth, along with temporary exchanges of plots between farmers as an agri-environmental tool to reduce agricultural impacts on environment.


Assuntos
Agricultura , Biodiversidade , Fazendeiros , Fazendas , Humanos , Recursos Naturais
10.
J Environ Manage ; 302(Pt A): 114066, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34872183

RESUMO

Providing for growing food demand while minimizing environmental degradation is a major contemporary environmental challenge. Agri-environmental schemes (AESs) are often promoted to meet this challenge by providing subsidies to farmers who adopt agri-environmental practices (AEPs). The success of these schemes depends on the ability to engage farmers, thus understanding farmers' perceptions about AEPs is pivotal. Yet, current knowledge is limited as most research explores farmer's attitudes towards existing AESs, often based on subsidies. We explored the attitudes of farmers and their communities towards five different AEPs, and towards a potential AES, in an area of intensive agriculture in Israel, where currently no AES are implemented. We conducted five focus group sessions with 41 farmers, 12 follow-up interviews, and a survey with 296 community members. Findings indicate that farmers' willingness to implement AEPs was driven by environmental, personal, and social considerations, particularly perceptions of "good farming" practices, such as community cohesiveness and maintaining control of one's field. Farmers' lack of trust in the government, and lack of personal or local experience with specific AEPs, are other major barriers for joining a potential AES. Farmers perceived financial compensation as a safety net, but placed social and cultural values on par with, or above, financial considerations for joining an AES. Farmers' communities demonstrated high support for implementing AEPs, indicating that communities could be an asset for AES development. Therefore, while incentives for many AESs are based primarily on monetary compensation, to achieve their desired long-term results they should also focus on farmer resilience, independence, knowledge creation, and socio-cultural capital development.


Assuntos
Agricultura , Fazendeiros , Atitude , Fazendas , Humanos , Israel
11.
Bioresour Technol ; 344(Pt B): 126272, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34737048

RESUMO

Cattle farm wastewater, as a significant reservoir for antibiotic resistance genes (ARGs), has received wide attention. Intracellular and extracellular ARGs (iARGs and eARGs) were detected during wastewater treatment, including solid-liquid separation, anaerobic regulation, upflow anaerobic sludge blanket (UASB) digestion, an anoxic-oxic-anoxic-oxic (A2O2) process, a membrane bioreactor (MBR), and ozone disinfection. Ten abundant ARGs were chosen as the target ARGs according to metagenomic sequencing. The concentrations of the total target iARGs and eARGs were 6.12 × 107 and 3.24 × 106 copy numbers/mL in raw wastewater, and then 3.79 × 103 and 3.95 × 105 copy numbers/mL in final effluent, because UASB, A2O2, MBR and ozone disinfection can gradually reduce the concentrations of most ARGs. The concentrations of ARGs were positively correlated with almost all wastewater quality indicators. Positive correlation was also observed between iARGs and Bacteroidetes, Firmicutes and Spirochaetes, indicating that the bacteria in these three phyla might be the main hosts of ARGs. Wastewater quality indicators and bacterial community composition affected the distribution and removal of ARGs during cattle wastewater treatment.


Assuntos
Antibacterianos , Purificação da Água , Animais , Antibacterianos/farmacologia , Bovinos , Resistência Microbiana a Medicamentos/genética , Fazendas , Genes Bacterianos/genética , Águas Residuárias/análise
12.
Food Chem ; 369: 130850, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461510

RESUMO

Recent studies have shown that mild to moderate iron chlorosis can have positive effects on grape quality potential, including volatile profile. The main objective of this work was to investigate, for the first time, how moderate iron stress in grapevines affects the presence of volatile organic compounds (VOCs) in wines. The study was carried out during 2018-2019 seasons, in 20 Tempranillo vineyard subzones with different degree of iron deficiency, located in Ribera del Duero (North-Central Spain). The results showed that moderate iron stress increased in wines the concentrations of VOCs associated with floral notes, such as 2-phenylacetaldehyde, 2-phenylethanol and 2-phenylethyl acetate, while reducing the presence of C6-alcohols, responsible for green-herbaceous aroma. A favourable reduction of pH and a betterment of parameters related to colour were detected in wines from iron deficient subzones. Chlorosis incidence was associated to improvements in wine sensory attributes as layer intensity, black fruit and aroma intensity.


Assuntos
Anemia Hipocrômica , Vitis , Compostos Orgânicos Voláteis , Vinho , Fazendas , Frutas/química , Humanos , Ferro , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise
13.
Sci Total Environ ; 802: 149657, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34464797

RESUMO

The decomposition of organic matter mediated by soil enzymes is the key process that transports carbon from the soil into the atmosphere. To better understand the effect of global warming on organic matter decomposition, we evaluated the temperature sensitivity (Q10) of invertase (EC3.2.1.26), ß-glucosidase (EC3.2.1.21), urease (EC3.1.1.5), acid phosphatase (EC3.1.3.2), and arylsulfatase (EC3.1.6.1) activities in red soil from the subtropical region and black soil from the mid-temperate region at 5, 15, 25, 35, and 45 °C. Further, the in-situ stoichiometry of the products released by enzymes was modelled. All of the enzyme activities in the tested soils increased with the increasing temperature (1.1-8.9 fold per 10 °C), indicating an enhanced degradation of the organic substrate with warming. In the lower temperature range (5-25 °C), Q10 of the enzyme activities in the red soil evaluated in terms of total enzyme activity index were more prominent than that in black soil (1.53 and 3.46 vs 1.16 and 3.19). Changes in the in-situ stoichiometry of enzyme products with warming indicated that, in colder months (Jan. to Apr. and Oct. to Dec.), the microbial nutrient demand in the red soil exhibited the following order, N > P > S > C. While in the black soil, it suggested that there is increasing microbial demand for only N and S. In the warmer months (May to Sep.), the microbial nutrient demands in the two soils were opposite to the colder months. The results suggested differential changes in microbial nutrient limitation with warming, which has significant implications for the carbon stocks management in farmlands under the changing global climate.


Assuntos
Microbiologia do Solo , Solo , Carbono , Fazendas , Aquecimento Global , Nutrientes
14.
Food Chem ; 369: 130753, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488135

RESUMO

Approximately 11.4 million tonnes of solid by-products and an increased amount of waste water will be generated during the 2020/21 coffee harvest. There are currently no truly value-adding uses for these potentially environmentally threatening species. This work presents the most wide-ranging chemical investigation of coffee by-products collected from farms to factories, including eight never previously investigated. Twenty compounds were found for the first time in coffee by-products including the bioactive neomangiferin, kaempferol-3-O-rutinoside, lup-20(29)-en-3-one and 3,4-dimethoxy cinnamic acid. Five by-products generated inside a factory showed caffeine (53.0-17.0 mg.g-1) and/or chlorogenic acid (72.9-10.1 mg.g-1) content comparable to coffee beans, while mature leaf from plant pruning presented not only high contents of both compounds (16.4 and 38.9 mg.g-1, respectively), but also of mangiferin (19.4 mg.g-1) besides a variety of flavonoids. Such by-products are a source of a range of bioactive compounds and could be explored with potential economic and certainly environmental benefits.


Assuntos
Café , Extratos Vegetais , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Fazendas
15.
Sci Total Environ ; 803: 150017, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34500278

RESUMO

Circular economy principle aims to achieve sustainable production systems, focusing on the waste valorisation and the reduction of gaseous losses to the atmosphere. Nitrogen (N) compounds in terms of ammonia (NH3) and nitrous oxide (N2O) represent the major losses to the atmosphere of laying hen manure management chain. We present a study aimed to evaluate NH3 and N2O emission and mitigation strategies at housing, storage and land spreading stages. The whole manure management chain was evaluated under different scenarios which combined mitigation strategies of each stage. Two intensive laying hen facilities were involved in the study. Evaluated mitigation strategies were: (i) frequency of manure removal from housing facility, (ii) dried manure storage after passing throughout a manure drying tunnel (MDT) compared to fresh manure storage and (iii) fresh or dried manure incorporation versus surface land application. Increasing the frequency of manure removal from 4 days to 1/3 daily, reduced N losses around 68%. Dried manure storage achieved around 75% reduction in N losses compared to fresh manure storage. Spreading dried manure on grassland surface reduced ≈77% NH3 losses in relation to the emission level reached by fresh manure. The reduction was similar when dried manure was incorporated compared to surface application of fresh manure (≈79%). A 40% reduction in N losses was achieved using the MDT compared to no drying strategy. In the whole manure management chain, the combination of strategies that most reduced N losses was: removal frequency of 1/3 daily, dry storage after passing through the MDT and incorporated land application. These strategies reduced N losses between 40 and 60% compared to the 4 days of removal frequency, fresh storage and surface application of fresh manure.


Assuntos
Esterco , Óxido Nitroso , Amônia/análise , Animais , Galinhas , Fazendas , Feminino , Óxido Nitroso/análise
16.
Sci Total Environ ; 802: 149946, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525759

RESUMO

Photovoltaic technology plays an important role in the sustainable development of clean energy, and arid areas are particularly ideal locations to build large-scale solar farms, all over the world. Modifications to the energy balance and water availability through the installation of large-scale solar farms, however, fundamentally affect the energy budget, water, and biogeochemical cycles. In-situ field observations, though, fail to draw definitive conclusions on how photovoltaic panels (PVs) affect the ambient environment, or how microclimates and soil moisture evolve under the long-term, continuous, cumulative influence of PVs. Here, we designed a synthetic model, integrating processes of energy budget and water cycle, to quantify the ecohydrological effects of PVs on soil microclimate and moisture regimes at different locations (zones) near individual PVs. Simulations run with a stochastically generated 100-year climate time series were examined to capture the evolutionary trends of soil microclimate and soil moisture. The results indicate that soil moisture content was increased by 59.8% to 113.6% in the Middle and Front zones, and soil temperature was decreased by 1.47 to 1.66 °C in all the sheltered zones, mainly because there was 5- 7 times more available water and ~27% less available radiation there, compared with the control zone. On the other hand, if the ground clearance of the PVs is too low, turbulence beneath hot PVs will have a significant influence on not only soil temperature but also soil moisture content. The innovative contribution of this study lies in reinforcing existing theoretical patterns for the development of soil microclimate and moisture dynamics influenced by PVs, and can be used to provide reliable insights into the hydrological and biogeochemical processes on Earth and the sustainable management of large-scale solar farms in arid ecosystems.


Assuntos
Microclima , Solo , China , Ecossistema , Fazendas , Água/análise
17.
Sci Total Environ ; 805: 150301, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34536860

RESUMO

Several studies in European and North American agroecosystems conclude that organic farming benefits birds compared to conventional farming. Nevertheless, there are some biases toward these geographic regions and farm size. Argentinian agroecosystems are particularly homogeneous with large arable fields and sparse uncultivated field margins (i.e. large-scale homogenous cropping systems). In Argentina only 0.55% of the total farmland is under organic farming. Thus, our aims were to assess differences in bird occupancy between organic versus conventional farming regimes, and whether bird occupancy varied in relation to annual crop proportion in both farming regimes in central Argentina agroecosystems. We surveyed 156 points in farms under conventional and 154 in organic farming regimes during two bird-breeding seasons. We used multi-species occupancy models with a Bayesian approach to estimate bird occupancy. We observed that the type of farming regime (organic in relation to conventional) had a weak effect on avian occupancy, varying by species and groups. Probability of occupancy was higher for a few insectivorous and omnivorous species but lower for carnivores in organic farms in relation to conventional ones. The proportion of annual crops was positively correlated with occupancy of an insectivore aerial forager, some insectivore foliage gleaners, a granivore, and some omnivorous species in organic farms, but not conventional farms. This work contributes to reducing geographic and small-scale heterogeneous cropping system biases in the avian agroecological literature. Our results, together with future studies needed to assess landscape configuration and composition, and resource availability for birds in each farming regime, will allow the evaluation of organic farming as a tool for the conservation of bird species in large-scale homogeneous cropping systems in temperate regions.


Assuntos
Biodiversidade , Melhoramento Vegetal , Agricultura , Animais , Argentina , Teorema de Bayes , Aves , Fazendas
18.
Sci Total Environ ; 805: 150286, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34537692

RESUMO

Due to the unfavorable soil conditions and water resources, the cropland use pattern in the farming-pastoral ecotone in northern China is complex. The program named "Grain for Green" has accelerated the cropland change. However, the complex cropland and retired cropland are challenging to monitor with remote sensing due to their spatially dispersed and easily confused with spectrally similar land use classes such as nature grasslands and non-cropped fields. Taking farming-pastoral ecotone in the northern foot of the Yinshan Mountains as a case study, we explored a classification approach for complex cropland and retired cropland, which was introduced as a specific land use class by using multi-temporal Landsat TM and OLI images with Google Earth Engine. During 1990-2000, cropland increased with a sharper growth and increased with a slower growth from 2001 to 2010, and then decreased significantly from 2011 to 2019, to lead the cropland area in 2019 was smaller than an area in 1990. We analyzed the spatiotemporal trajectories of retired cropland in 2019 using the Land Use Change Trajectory method to evaluate its source. In our finding, approximately 77% of retired cropland was labelled as cropland before 2019; albeit, not all retired cropland was converted from cropland. Moreover, we qualitatively assessed the vegetation dynamics in the study area by utilizing the long-term NDVI-mean value to reveal that vegetation coverage has shown a continuously increasing trend. It is related to the decline of cropland and the increase of retired cropland at the same rate. Our results highlighted that the "Grain for Green" program had led the vegetation restoration in the farming-pastoral ecotone. Our approach for monitoring cropland and retired cropland can improve the understanding of the driving factors and consequences of these critical land use change trajectories.


Assuntos
Agricultura , Solo , China , Grão Comestível , Fazendas
19.
Sci Total Environ ; 806(Pt 3): 150685, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34600986

RESUMO

Livestock farms are recognized as the main sources of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) with potential implications for human health. In this study, we systematically analyzed microbiome composition, distribution of ARGs and mobile genetic elements (MGEs) in the oropharynx and gut of workers in cattle farms and surrounding villagers, cattle feces and farm air, and the relationship of microbial communities among farm air, cattle feces and farmworkers (oropharynx and gut). Exposure to the farm environment may have remodeled farmworkers' oropharynx and gut microbiota, with reduced microbial diversity (P < 0.05) and enrichment of some opportunistic pathogenic bacteria like Shigella, Streptococcus, and Neisseria in the oropharynx. Meanwhile, compared with villagers, ARG abundance in oropharynx of farmworkers increased significantly (P < 0.05), but, no significant difference in gut (P > 0.05). Microbial composition and ARG profile in farmworkers might be influenced by working time and work type, ARG abundance in farmworkers' gut was positively correlated with working time (P < 0.01), and higher ARG abundance was found in the oropharynx of drovers. The network analysis revealed that 4 MGEs (tnpA-01, tnpA-04, Tp614, and IS613), 5 phyla (e.g. Bacteroidetes, Fusobacteria, and TM7), and 6 genera were significantly associated with 37 ARGs (ρ > 0.6, P < 0.01). Overall, our results indicated that farm exposure may have affected the microbial composition and increased ARG abundance of farmworkers. Transmission of some ARGs may have occurred among the environment, animals and humans via host bacteria, which might pose a potential threat to human health.


Assuntos
Antibacterianos , Microbiota , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Animais , Antibacterianos/farmacologia , Bovinos , Resistência Microbiana a Medicamentos , Fazendas , Genes Bacterianos , Orofaringe
20.
Sci Total Environ ; 806(Pt 3): 150608, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606854

RESUMO

Nitrous oxide (N2O) emissions from dairy-grazing pastures can be dominated by large emissions from small areas ('hotspots') frequently used by grazing dairy cattle (i.e., water troughs and gateways). N2O emissions from these hotspots are quantified by investigating whether N2O emissions and emission factors (% of applied N emitted as N2O, EF3) from potential hotspots are different from non-hotspots. To better characterise N2O emissions from hotspots and non-hotspots of farms to understand their contributions to national agricultural greenhouse gas inventory calculations, a series of measurements were conducted during winter and spring on two NZ typical dairy farms with contrasting soil drainage (poorly versus well drained). Before measurements were taken, the soils either received a cow urine application or remained untreated. The results showed that changes in water-filled pore space (WFPS) and mineral N around water troughs and gateways, due to additional stock movements and disproportionate excreta-N deposition during previous grazing events, affected both background and total N2O emissions. But there was little impact on EF3 values (calculated using IPCC guidelines) from deposited urine between hotspot and pasture areas. These results suggest the same EF3 values can be used for both to calculate emissions from urine deposited on grazed pastures. However, these results raise concerns about higher background emission in hotspots subtracted from measured emissions from urine-N deposition in calculating EF3 values and discounting the effects of disproportionate N inputs in intensive agriculture on increased background emissions (legacy effect). This IPCC inventory method does not account for the legacy effect of N loading prior to the measurements which may underestimate the emissions. Thus, an allowance for higher hotspot background emissions could be included in the Inventory to accurately estimate total emissions from agriculture.


Assuntos
Gases de Efeito Estufa , Óxido Nitroso , Agricultura , Animais , Bovinos , Fazendas , Feminino , Gases de Efeito Estufa/análise , Óxido Nitroso/análise , Solo
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