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1.
Sci Rep ; 13(1): 297, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609510

RESUMO

Bush encroachment affects much of the Namibian woodland landscape, causing significant loss of open savannah habitat and farm profits. Thinning of the trees/shrubs is recommended; however, research is required to identify the overall efficacy and effects of this method on the woodland habitat. We aimed to examine the effect of the thinning strategy applied on the vegetation structure of encroaching tree/shrub species, as well as the sighting lines of the habitat. Vegetation surveys were done on three freehold farms in north-central Namibia. The study utilised a combination of a blocked and split-plot study design: each block consisted of a pair of thinned and non-thinned plots with multiple subplots. Thinned plots had been manually thinned, with a post-thinning age of three years or more. Results revealed that tree/shrub abundance differed between species; thinned areas had the least abundance and overall species-treatment interactions were significant. Thinning caused a significant reduction in overall tree/shrub densities, settling within the recommended range for the area. Thinning also significantly reduced the average tree/shrub height, canopy area, medium-sized trees/shrubs, and increased sighting lines. This confirms a bush encroachment mitigation strategy that favours grass cover, and wildlife that rely on longer sighting lines for safety or when hunting.


Assuntos
Ecossistema , Madeira , Fazendas , Namíbia , Madeira/fisiologia , Florestas , Plantas , Árvores/fisiologia
2.
PLoS One ; 18(1): e0268385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656908

RESUMO

Downy mildew is caused by Plasmopara viticola, an obligate oomycete plant pathogen, a devasting disease of grapevine. To protect plants from the disease, complex III inhibitors are among the fungicides widely used. They specifically target the mitochondrial cytochrome b (cytb) of the pathogen to block cellular respiration mechanisms. In the French vineyard, P. viticola has developed resistance against a first group of these fungicides, the Quinone outside Inhibitors (QoI), with a single amino acid substitution G143A in its cytb mitochondrial sequence. The use of QoI was limited and another type of fungicide, the Quinone inside Inhibitors, targeting the same gene and highly effective against oomycetes, was used instead. Recently however, less sensitive P. viticola populations were detected after treatments with some inhibitors, in particular ametoctradin and cyazofamid. By isolating single-sporangia P. viticola strains resistant to these fungicides, we characterized new variants in the cytb sequences associated with cyazofamid resistance: a point mutation (L201S) and more strikingly, two insertions (E203-DE-V204, E203-VE-V204). In parallel with the classical tools, pyrosequencing and qPCR, we then benchmarked short and long-reads NGS technologies (Ion Torrent, Illumina, Oxford Nanopore Technologies) to sequence the complete cytb with a view to detecting and assessing the proportion of resistant variants of P. viticola at the scale of a field population. Eighteen populations collected from French vineyard fields in 2020 were analysed: 12 showed a variable proportion of G143A, 11 of E203-DE-V204 and 7 populations of the S34L variant that confers resistance to ametoctradin. Interestingly, the long reads were able to identify variants, including SNPs, with confidence and to detect a small proportion of P. viticola with multiple variants along the same cytb sequence. Overall, NGS appears to be a promising method for assessing fungicide resistance of pathogens linked to cytb modifications at the field population level. This approach could rapidly become a robust decision support tool for resistance management in the future.


Assuntos
Fungicidas Industriais , Oomicetos , Vitis , Citocromos b/genética , Complexo III da Cadeia de Transporte de Elétrons/genética , Fazendas , Fungicidas Industriais/farmacologia , Oomicetos/genética , Doenças das Plantas/microbiologia , Estrobilurinas/farmacologia , Vitis/microbiologia
3.
Science ; 379(6628): 140-141, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36634167

RESUMO

Farming edible insects can help improve food security and boost developing economies.


Assuntos
Alérgenos , Insetos , Animais , Humanos , Agricultura , Fazendas
4.
Science ; 379(6628): 138-139, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36634163

RESUMO

Insect farming for livestock feed has the potential to replace conventional feed.


Assuntos
Ração Animal , Gado , Animais , Insetos , Agricultura , Fazendas
5.
Artigo em Inglês | MEDLINE | ID: mdl-36673714

RESUMO

The green production behavior of pig farmers is the basis for high-quality development in animal husbandry. In order to solve the problem of poor green production behaviors in small- and medium-sized pig farmers, it is necessary to analyze the influencing factors and how they interact with each other. The Rational Peasant Theory and Prospect Theory were used in this paper to analyze the occurrence motivation of the green production behaviors of small- and medium-sized pig farmers. The Logit model and the ISM analysis method were used to test the influencing factors and their mechanisms. This was conducted using data from a study of 747 small- and medium-sized pig farmers in Henan Province. The results show that the green production behaviors of small- and medium-sized pig farmers are motivated by internal expected return, affected by the monitoring pressure from external stakeholders and limited by their own resource capacity; the influencing factors of different green production behaviors are different, and there are more influencing factors of scientific disease control, standardized management and waste recycling than of rational feeding. The following shows how the influencing factors on pig farmers' green production behavior interact with one another: level of education → external pressure, farming conditions and operating characteristics → cognition of return → green production behavior (i.e., cognition of return is the direct factor; external pressure, farming conditions and operating characteristics are indirect factors; and level of education is the underlying factor). Some measures should be implemented to promote green production behaviors, such as the continuation of the support for green production, the strengthening of supervision and publicity, the increasing of investment in technology and equipment, and the improving of the green production literacy of farmers. In conclusion, this paper deepens the understanding of the mechanism of green production behaviors of small- and medium-sized pig farmers, and provides the theoretical basis and concrete measures for the government and for pig farmers.


Assuntos
Agricultura , Fazendeiros , Suínos , Animais , Humanos , Inquéritos e Questionários , Criação de Animais Domésticos/métodos , Fazendas , China
6.
Artigo em Inglês | MEDLINE | ID: mdl-36673722

RESUMO

Farmland heavy metal pollution-caused by both human activity and natural processes-is a major global issue. In the current study, principal component analysis (PCA), cluster analysis (CA), rare earth elements and yttrium (REY) analysis, and isotope fingerprinting were combined to identify sources of heavy metal pollution in soil from different farmland types in the upper-middle area of the Yangtze River. The concentrations of Zn and Cu were found to be higher in the vegetable base and tea plantation soil compared with their concentrations in the orangery soil. On the other hand, greater accumulation of Cd and Pb was observed in the orangery soil versus the vegetable base and tea plantation soils. Influenced by the type of bedrock, REY was significantly enriched in the orangery soil and depleted in the vegetable base soil, as compared with the tea plantation soil. The Pb isotopic compositions of the tea plantation (1.173-1.193 for 206Pb/207Pb and 2.070-2.110 for 208Pb/206Pb) and vegetable base (1.181-1.217 for 206Pb/207Pb and 2.052-2.116 for 208Pb/206Pb) soils were comparable to those of coal combustion soil. The compositions of 206Pb/207Pb (1.149-1.170) and 208Pb/206Pb (2.121-2.143) in the orangery soil fell between those observed in soils obtained from coal combustion and ore smelting sites. Using the IsoSource model, the atmospheric Pb contributions of the vegetable base, tea plantation, and orangery soils were calculated to be 66.6%, 90.1%, and 82.0%, respectively, and the bedrock contributions of Pb were calculated to be 33.3%, 9.90%, and 18.1%, respectively. Based on the PCA, CA, and REY results, as well as the Pb isotope model, it appears that heavy metals in the orangery soil may be derived from atmospheric deposition and bedrock weathering, while heavy metals in the vegetable base and tea plantation soils may be derived from mining and the use of fertilizer.


Assuntos
Metais Pesados , Metais Terras Raras , Poluentes do Solo , Humanos , Solo , Fazendas , Ítrio/análise , Chumbo/análise , Rios , Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Metais Pesados/análise , Metais Terras Raras/análise , Verduras , Isótopos/análise , Carvão Mineral/análise , Chá , China , Medição de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-36673774

RESUMO

A regional-scale survey was conducted to assess the occurrence, distribution, and risk of two extensively used pesticides (organophosphate pesticides and pyrethroids) in agricultural soils from the Pearl River Delta (PRD), South China. All target organophosphate pesticides (OPPs) and pyrethroids (PYs) were detected in the soil samples and both with a detection rate of 100%. The residues of the sum of six OPPs and the sum of four PYs were in the range of LOD-991 ng/g and 8.76-2810 ng/g, respectively. Dimethoate was the dominant OPPs, and fenpropathrin was the predominant PYs in the soils of the PRD region. With intensive agricultural activities, higher residues of OPPs and PYs in soils were detected closer to the seaside, among which Zhuhai city and Huizhou city suffered more serious combined pesticide pollution. The vertical compositional profiles showed that dimethoate could be detected through each soil layer in the PRD region's nine cities. The human exposure estimation of OPPs showed insignificant risks to the local population. In contrast, cypermethrin and fenpropathrin showed a potential ecological risk of 2.5% and 3.75% of the sampling sites, respectively. These results can facilitate those commonly used pesticide controls and promote sustainable soil management.


Assuntos
Inseticidas , Praguicidas , Piretrinas , Poluentes do Solo , Humanos , Fazendas , Dimetoato , Rios , Piretrinas/análise , Praguicidas/análise , Solo/química , Compostos Organofosforados , China , Monitoramento Ambiental , Poluentes do Solo/análise
8.
Sci Rep ; 13(1): 685, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639408

RESUMO

The poultry red mite (PRM), Dermanyssus gallinae, is arguably the most harmful, ubiquitous haematophagous ectoparasite infesting egg-laying hens. PRM is a vector of various microorganisms, with some being important for food microbiology and public health. The present study aimed to investigate the presence of specific pathogens, including Escherichia coli, Salmonella spp. and Listeria spp., carried by PRM infesting a chicken farm in Greece. Mites were caught using cardboard traps (Avivet), and 100 unwashed PRM were homogenized and used for microbiological cultures. Microbiological cultures were carried out on general and selective substrates to detect the above-mentioned bacteria. Specifically for Listeria spp., DNA was extracted from bacteria grown in Tryptone Soya Yeast Extract Agar using a commercial kit. The hly gene encoding the Listeriolysin O protein was amplified by PCR. Mites were identified as D. gallinae using morphological keys as well as by COI DNA barcoding. Microbiological cultures and PCR assays were positive for Listeria monocytogenes. No other bacteria were detected. The current study constitutes the first molecular isolation of L. monocytogenes from D. gallinae, confirming that PRM can carry this food-borne pathogen. PRM control measures and hygiene practices should be applied to minimize any possible contamination risk of poultry products with L. monocytogenes and safeguard public health.


Assuntos
Listeria monocytogenes , Infestações por Ácaros , Ácaros , Doenças das Aves Domésticas , Trombiculidae , Animais , Feminino , Galinhas , Aves Domésticas , Infestações por Ácaros/parasitologia , Listeria monocytogenes/genética , Grécia , Fazendas , Doenças das Aves Domésticas/parasitologia , Ácaros/genética , Escherichia coli
9.
Sensors (Basel) ; 23(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36679645

RESUMO

The potential of image proximal sensing for agricultural applications has been a prolific scientific subject in the recent literature. Its main appeal lies in the sensing of precise information about plant status, which is either harder or impossible to extract from lower-resolution downward-looking image sensors such as satellite or drone imagery. Yet, many theoretical and practical problems arise when dealing with proximal sensing, especially on perennial crops such as vineyards. Indeed, vineyards exhibit challenging physical obstacles and many degrees of variability in their layout. In this paper, we present the design of a mobile camera suited to vineyards and harsh experimental conditions, as well as the results and assessments of 8 years' worth of studies using that camera. These projects ranged from in-field yield estimation (berry counting) to disease detection, providing new insights on typical viticulture problems that could also be generalized to orchard crops. Different recommendations are then provided using small case studies, such as the difficulties related to framing plots with different structures or the mounting of the sensor on a moving vehicle. While results stress the obvious importance and strong benefits of a thorough experimental design, they also indicate some inescapable pitfalls, illustrating the need for more robust image analysis algorithms and better databases. We believe sharing that experience with the scientific community can only benefit the future development of these innovative approaches.


Assuntos
Agricultura , Algoritmos , Fazendas , Retroalimentação , Agricultura/métodos , Processamento de Imagem Assistida por Computador , Produtos Agrícolas
10.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688760

RESUMO

Extraintestinal pathogenic Escherichia coli (ExPEC) associated infections are significant health concerns for both animals and humans. ExPEC strains are associated with various infections in humans, i.e. urinary tract infections, meningitis, septicemia, and other infections. Over the few years, several studies revealed, food animals act as a reservoir for ExPEC pathovars, but there is no information about the agricultural sector. In particular, the extensive use of antibiotics in food animals and agricultural settings could be significantly contributed to the emergence of antibiotic-resistant pathogens. However, global outbreaks of food-borne illnesses from contaminated food have made a significant concern for both public health and food safety. This review focuses on the reservoirs for ExPEC and their potential circulation between animals, humans, and environment. In this, we first report that the agricultural setting could be the reservoir of ExPEC and can play a role in disseminating antimicrobial-resistant ExPEC. A thorough understanding of ExPEC ecology, reservoirs, and transmission dynamics can significantly contribute to reducing the burden of ExPEC-associated infections. Overall, the study provides the important data on the current state of knowledge for different reservoirs with dynamic, dissemination, and transmission of antimicrobial-resistance ExPEC in animals, humans, and environment in the "One-Health" context.


Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Animais , Humanos , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Fazendas , Farmacorresistência Bacteriana Múltipla , Antibacterianos/farmacologia , Medição de Risco
11.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688778

RESUMO

Extended-spectrum beta-lactamases (ESBLs) and AmpC beta-lactamases (AmpCs)-producing Enterobacteriaceae have been increasingly reported and imposing significant threat to public. Livestock production industry might be the important source for clinically important ESBL-producing Enterobacteriaceae. This study aims to investigate the resistance profile, phenotypic ESBL production, beta-lactamase genes, virulence factors, and plasmid replicon types among 59 Enterobacteriaceae strains isolated from poultry faecal samples in Malaysia's commercial poultry farm. There were 38.7% and 32.3% of Escherichia coli resistant to cefotaxime and cefoxitin, respectively, while Klebsiellaspp. demonstrated resistance rate of 52.6% to both mentioned antimicrobials. Majority of the E. coli isolates carried blaTEM and blaCMY-2 group. blaSHV was the most prevalent gene detected in Klebsiellaspp., followed by blaDHA and blaTEM. Resistance to extended spectrum cephalosporin in our isolates was primarily mediated by plasmid mediated AmpC beta-lactamase such as CMY-2 group and DHA enzyme. The CTX-M genes were found in two ESBL-producing E. coli. IncF, IncI1, and IncN plasmids were most frequently detected in E. coli and Klebsiellaspp. The virulence factor, including EAST1 and pAA were identified at low frequency. This study highlights the poultry as a reservoir of resistance and virulence determinants and prevalence of plasmids in Enterobacteriaceae might drive their dissemination.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Animais , Escherichia coli/genética , Aves Domésticas , Infecções por Escherichia coli/veterinária , Fazendas , Enterobacteriaceae/genética , Malásia , Proteínas de Bactérias/genética , beta-Lactamases/genética , Plasmídeos , Antibacterianos
12.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688777

RESUMO

The silent pandemic of antimicrobial resistance (AR) has been on the rise for the past decades. It is essential to determine the burden of AR in animal farms that spreads leading to human exposure. A total of 100 samples including soil, litter, animal excreta, and wastewater were collected from seven conventional and one organic farm in Egypt. The prevalence of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-producing E. coli), fluoroquinolone-resistant E. coli, fluoroquinolone-resistant Salmonella, and vancomycin-resistant enterococci (VRE) was determined in studied farms. Conventional farms had a higher prevalence of antimicrobial-resistant bacteria than the organic farm (73.81% vs. 18.75%, P < .001). In conventional farms 21.43% of samples yielded mixed isolates; however, in the organic farm, only single isolates of ESBL-producing E. coli were detected. The most prevalent ESBL-production gene was blaTEM (82.14%), followed by blaCTX-M (48.22%), and blaSHV (19.64%), either alone or in combination with another gene. The most prevalent fluoroquinolone-resistance genes were qnrS (82.69%) and qnrB (42.30%), either alone or in combination with another gene(s). A total of five VRE isolates harbored vanA gene (83.33%), none carried vanB gene, and one isolate was negative for both genes. The studied conventional livestock farms had significantly higher rates of serious AR threats than the organic farm.


Assuntos
Anti-Infecciosos , Infecções por Escherichia coli , Humanos , Animais , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Fazendas , Gado , Estudos Transversais , Prevalência , Egito , beta-Lactamases/genética , Fluoroquinolonas , Antibacterianos
13.
Theor Appl Genet ; 136(1): 1-12, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36688966

RESUMO

KEY MESSAGE: VCU trials can provide unbiased estimates of post-breeding trends given that all data is used. Dropping data of genotypes tested for up to two years may result in biased post-breeding trend estimates. Increasing yield trends are seen on-farm in Germany. The increase is based on genetic trend in registered genotypes and changes in agronomic practices and climate. To estimate both genetic and non-genetic trends, historical wheat data from variety trials evaluating a varieties' value for cultivation und use (VCU) were analyzed. VCU datasets include information on varieties as well as on genotypes that were submitted by breeders and tested in trials but could not make it to registration. Therefore, the population of registered varieties (post-registration population) is a subset of the population of genotypes tested in VCU trials (post-breeding population). To assess post-registration genetic trend, historical VCU trial datasets are often reduced, e.g. to registered varieties only. This kind of drop-out mechanism is statistically informative which affects variance component estimates and which can affect trend estimates. To investigate the effect of this informative drop-out on trend estimates, a simulation study was conducted mimicking the structure of German winter wheat VCU trials. Zero post-breeding trends were simulated. Results showed unbiased estimates of post-breeding trends when using all data. When restricting data to genotypes tested for at least three years, a positive genetic trend of 0.11 dt ha-1 year-1 and a negative non-genetic trend (- 0.11 dt ha-1 year-1) were observed. Bias increased with increasing genotype-by-year variance and disappeared with random selection. We simulated single-trait selection, whereas decisions in VCU trials consider multiple traits, so selection intensity per trait is considerably lower. Hence, our results provide an upper bound for the bias expected in practice.


Assuntos
Agricultura , Melhoramento Vegetal , Fenótipo , Genótipo , Fazendas
14.
PeerJ ; 11: e14661, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36691487

RESUMO

Background: Potato is an essential food staple and a critical tuber crop for rural livelihoods in Ethiopia, where many pathogenic pests are threatening production. Bacterial wilt, also known as brown rot of potato, ranks among the diseases that most affect many potato farmers in Ethiopia and the disease losses dramatically threatening the vibrant potato sector even in the highlands of the country where it has been uncommon so far. Methodology: To devise a strategy towards boosting potato productivity in Ethiopia where food insecurity is most prevalent, production constraints should be investigated and properly addressed. Hence, we have used existing reviews and reports on the subjects, such as textbooks, and proceeding and conference abstracts in Plant Protection Society of Ethiopia; Web of Science; Google Scholar; Research Gate and CIP's database to document most relevant information on the occurrence, distribution, and disease management of bacterial wilt in Ethiopia. Results: Provision of comprehensive information on potato bacterial wilt occurrence, distribution, and management techniques are crucial for potato growers, researchers and stakeholders engaged on potato industry. In this review, we provided insights on the history, status, and future perspectives of potato bacterial wilt in Ethiopia. Conclusions: Awareness of potato bacterial wilt and integrated disease management approaches could bring a fundamental impact to the farming community mostly to smallholder farmers in developing countries. This document compiled such imperative information targeting bacterial wilt management techniques to ensure food security.


Assuntos
Solanum tuberosum , Humanos , Solanum tuberosum/microbiologia , Etiópia , Agricultura/métodos , Fazendas , Fazendeiros
15.
Sensors (Basel) ; 23(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36617130

RESUMO

Effective livestock management is critical for cattle farms in today's competitive era of smart modern farming. To ensure farm management solutions are efficient, affordable, and scalable, the manual identification and detection of cattle are not feasible in today's farming systems. Fortunately, automatic tracking and identification systems have greatly improved in recent years. Moreover, correctly identifying individual cows is an integral part of predicting behavior during estrus. By doing so, we can monitor a cow's behavior, and pinpoint the right time for artificial insemination. However, most previous techniques have relied on direct observation, increasing the human workload. To overcome this problem, this paper proposes the use of state-of-the-art deep learning-based Multi-Object Tracking (MOT) algorithms for a complete system that can automatically and continuously detect and track cattle using an RGB camera. This study compares state-of-the-art MOTs, such as Deep-SORT, Strong-SORT, and customized light-weight tracking algorithms. To improve the tracking accuracy of these deep learning methods, this paper presents an enhanced re-identification approach for a black cattle dataset in Strong-SORT. For evaluating MOT by detection, the system used the YOLO v5 and v7, as a comparison with the instance segmentation model Detectron-2, to detect and classify the cattle. The high cattle-tracking accuracy with a Multi-Object Tracking Accuracy (MOTA) was 96.88%. Using these methods, the findings demonstrate a highly accurate and robust cattle tracking system, which can be applied to innovative monitoring systems for agricultural applications. The effectiveness and efficiency of the proposed system were demonstrated by analyzing a sample of video footage. The proposed method was developed to balance the trade-off between costs and management, thereby improving the productivity and profitability of dairy farms; however, this method can be adapted to other domestic species.


Assuntos
Aprendizado Profundo , Feminino , Bovinos , Humanos , Animais , Indústria de Laticínios/métodos , Algoritmos , Agricultura , Fazendas
16.
Huan Jing Ke Xue ; 44(1): 436-443, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635831

RESUMO

A strain of Enterobacter was screened from cadmium and arsenic contaminated farmland soil and its passivation mechanism of cadmium and arsenic were explored through removing performance and characterization experiments. The results showed that the screened strain M5 was identified as Enterobacter sp. with a sulfate-reduction function, and its maximum resistance concentration was approximately 1 mmol·L-1 to cadmium and arsenic. In the simulation system, the maximum removal efficiencies of cadmium and arsenic were 94.13% and 27.26% by strain M5, respectively. The results of SEM-EDS and XRD confirmed that Cd and As were fixed to CdS and As2S3, and XPS results showed that carboxyl groups, hydroxyl groups, and amide groups on the surface of the bacteria were mainly involved in biological adsorption. These results can provide new ideas and a theoretical basis for microbial applications to soil remediations for heavy metal pollution.


Assuntos
Arsênio , Poluentes do Solo , Cádmio/análise , Enterobacter , Fazendas , Poluentes do Solo/análise , Solo , Biodegradação Ambiental
17.
Huan Jing Ke Xue ; 44(1): 356-366, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635823

RESUMO

The farmland environment is directly related to the quality and safety of agricultural products. In order to understand the characteristics and main influencing factors of heavy metals in farmland soil in the Yellow River irrigation area of Ningxia, sampling and monitoring were conducted for five consecutive years from 2017 to 2021, and the distribution characteristics and correlation of heavy metals were analyzed. The pollution status and potential ecological risks of heavy metals were evaluated, and the main sources of heavy metals in farmland were analyzed. The results showed that the average values of Pb, As, Zn, Ni, Cu, Hg, Cr, and Cd in the soil of the Ningxia Yellow River irrigation area were 19.74, 11.67, 66.88, 29.09, 22.55, 0.03, 62.27, and 0.19 mg·kg-1, respectively, which were enriched to some extent compared with the background values of the soil environment in Ningxia. Among them, Hg and Cd had middle- and high-grade ecological risk points; however, none of them exceeded the control value of agricultural land soil pollution risk, and all sampling sites had no high-risk or extremely high-risk levels. The results of source analysis based on positive matrix factorization (PMF) and correlation analysis showed that there were five main sources of heavy metals in farmland soil in the study area: natural sources, mixed sources of industrial and mining activities and the production and life of residents, transportation sources, agricultural production activities sources, and industrial sources, with contribution rates of 26.54%, 25.59%, 22.52%, 15.63%, and 9.72%, respectively. On the whole, the heavy metals in farmland soil in the Ningxia Yellow River irrigation area did not exceed the standard, and there was no high-level ecological risk. The production environment of the farmland soil was good, but the contribution rate of human activities to soil heavy metals was large.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Humanos , Solo , Fazendas , Cádmio/análise , Rios , Monitoramento Ambiental/métodos , Poluentes do Solo/análise , Metais Pesados/análise , Mercúrio/análise , Medição de Risco , China
18.
Huan Jing Ke Xue ; 44(1): 482-493, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635836

RESUMO

This study was conducted to clarify the structure and function of the fungal community and the microecology change characteristics of farmland soil fertility response to different fallow rotation patterns. It aimed to provide a reference for promoting farmland ecological restoration and farmland quality improvement in the alluvial plain of the lower Yellow River. Farmland soil subject to a long-term rotation fallow experiment since 2018 was studied using Illumina MiSeq high-throughput sequencing technology, and the 'FUNGuild' fungal function prediction tool was used to analyze differences in soil fungal community structure and function under the following four rotation fallow regimes: long fallow (LF), winter wheat and summer fallow (WF), winter fallow and summer maize (FM), and annual rotation of winter wheat and summer maize (WM). The results showed that LF (fallow lasting two years) increased the richness and diversity of fungal communities in the topsoil (0-20 cm layer), whereas WF increased the richness and diversity of fungi in the deep soil (20-40 cm layer) after winter wheat harvest. A total of 2262 OTU were obtained from all soil samples, which were divided into 14 phyla, 34 classes, 75 orders, 169 families, 309 genera, and 523 species. OTU shared by the two soil layers included 420 types (0-20 cm layer) and 253 types (20-40 cm layer), respectively. The fungal community structure of the four rotation fallow soils was similar at the phylum level, mainly including Ascomycota, Basidiomycota, and Mortierellomycota. The total abundances of the three dominant bacteria were 91.69%-96.91% (0-20 cm layer) and 91.67%-94.86% (20-40 cm layer), respectively. Principal component analysis showed that the first principal component (PC1) and the second principal component (PC2) could explain the difference in community structure by 45.56% (0-20 cm layer) and 46.20% (20-40 cm layer). Additionally, the LDA results of LEfSe (threshold was 4.0) showed that there were 64 fungal evolutionary branches in LF, FM, WF, and WM with statistically significant differences (P<0.05). According to RDA analysis, total organic carbon (TOC), total phosphorus (TP), available nitrogen (AN), and soil water content (SWC) were the main environmental factors that significantly affected fungal community in the 0-40 cm soil layer (P<0.05). The functional prediction with FUNGuild showed that the main nutrient types among different treatments in different soil layers were saprotrophic, saprotrophic-symbiotrophic, pathotrophic-saprotrophic-symbiotrophic, and pathotrophic. In LF, the nutrient type of topsoil was mainly pathotrophic-saprotrophic-symbiotrophic, whereas in deep soil, the relative abundance of pathotrophic fungi was the highest. Additionally, in the treatments with planted wheat or corn (FM, WF, and WM), saprotrophic was the main type in both soil layers. Therefore, different fallow patterns were linked to variation in the structure, diversity, and nutrient types of soil fungal communities. Based on these results, seasonal fallow practices could regulate the farmland soil micro-ecological environment of intensive planting and promote the health and harmony of farmland soil ecosystems.


Assuntos
Micobioma , Solo , Humanos , Solo/química , Ecossistema , Fazendas , Rios , Rotação , Triticum , Microbiologia do Solo
19.
Proc Natl Acad Sci U S A ; 120(4): e2209475119, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36649433

RESUMO

Nearly 20 y ago, Jared Diamond and Peter Bellwood reviewed the evidence for the associated spread of farming and large language families by the demographic expansions of farmers. Since then, advances in obtaining and analyzing genomic data from modern and ancient populations have transformed our knowledge of human dispersals during the Holocene. Here, we provide an overview of Holocene dispersals in the light of genomic evidence and conclude that they have a complex history. Even when there is a demonstrated connection between a demographic expansion of people, the spread of agriculture, and the spread of a particular language family, the outcome in the results of contact between expanding and resident groups is highly variable. Further research is needed to identify the factors and social circumstances that have influenced this variation and complex history.


Assuntos
Agricultura , Genômica , Humanos , História Antiga , Fazendas , Migração Humana
20.
World J Microbiol Biotechnol ; 39(3): 81, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36646798

RESUMO

Hexavalent chromium is resistant to degradation and harmful toxic substance to environment and community health. Physicochemical treatment methods are demanding high cost, used large quantities of chemicals & energy, release large amount of secondary toxic degradants. Mycoremediation is an eco-friendly alternative treatment method. The main objective of this research is to isolate and characterize chrome (VI) tolerant fungi from farm soil & industry effluent for mycoremedation purpose. The screening and isolation of yeast was carried out on potato dextrose agar media. PDA and broth assay test for fungi tolerance to hexavalent chromium at different concentration, temperature and pH was evaluated. Fungi species was identified biochemically using Biolog Microstation depending on carbon utilization and chemical sensitivity test. The result revealed that 10 yeast species was identified with full ID from effluent waste and farm soil based on their probability ≥  75% and similarity index ≥  0.5 as well as their Cr (VI) tolerance ability up to 2500 ppm. These are Yarrowia lipolytica (100%, 0.7), Cryptococcus luteolus(100%, 0.64), Rhodotorula aurantiaca A(100%, 0.62), Ustilago maydis(100%, 0.58) Trichosporon beigelii B (100%, 0.51), Cryptococcus terreus A (100%, 0.62), Zygosaccharomyces bailii (98%, 0.65), Nadsoniafulvenscens (90%, 0.62), Schizoblastosporonstarkeyihenricii (89%, 0.56), Endomycopsis vivi (84%, 0.62), Rhodotorula pustula (Sim, 0.59). Two yeast species Yarrowia lipolytica and Nadsoniafulvenscens show the highest growth mean Optical density (OD) measure 0.74 ± 0.2 & 0.60 ± 0.2 respectively at pH 7 & 25 °C. The highest tolerance index (mm) was recorded by Schizoblastosporon starkey henricii 0.3067 ± 0.152. Cr (VI)-tolerance ability of these yeast strains used in the development of chromium-bioremediation technologies provide an alternative option for chromium sequestration after HPLC analysis& molecular characterization.


Assuntos
Solo , Verduras , Etiópia , Fazendas , Cromo/metabolismo , Leveduras/metabolismo , Biodegradação Ambiental
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