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1.
Sci Rep ; 14(1): 4995, 2024 02 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424119

RESUMEN

Consuming foods high in iron benefits metabolic processes as well as the development of the neonatal and fetal brain. Despite the significance of eating foods high in iron for public health, Ethiopian practices are still limited when compared to the World Health Organization's (WHO) assessment of its consumption of such foods. This study used the Ethiopia Demographic and Health Survey (EDHS) to evaluate the consumption of iron-rich foods, regional clustering, and related characteristics among children aged 6-23 months. The information was taken from the typical EDHS 2019 dataset, which included a weighted sample of 1572 young children aged 6-23 months old in total. Utilizing Kuldorff's SaTScan version 9.6 software, spatial scan statistics were produced. Software from ArcGIS 10.8 was used to display the regional distribution of inadequate consumption of foods high in iron. Utilizing multilevel or mixed effects logistic regression analysis, the associated determinants for a healthy diet rich in foods containing iron were found. In the final model, a P-value of < 0.05 was announced as a statistical significance variable. Overall, in Ethiopia, children aged 6-23 months consumed iron-rich foods at a rate of 27.14% (95% CI 24.99-29.39). Poor intake of foods heavy in iron is concentrated in Ethiopia's regional states of Afar, a sizable portion of Amhara, Oromia, Tigray, Somali, Gambela, and SNNPS. Primary and secondary education (AOR = 1.73, CI 95%: 1.23, 2.41), and (AOR = 1.97,CI 95%: 1.25, 3.10), having ≥ 2 under five children, and current status of breastfeeding (AOR = 0.62 (CI 95%: 0.45, 0.84), and (AOR = 0.32, CI 95%: 0.23, 0.44), giving birth at health facilities (AOR = 1.51, CI 95%: 1.06, 2.13),being from Afar and Somali regions (AOR = 0.39, 95%: 0.17, 0.93), and (AOR = 0.26, CI 95%: 0.10, 0.69) have shown statistically significant association with the outcome variable respectively. In Ethiopia, providing high-iron meals and supplements to under-2-year-old children represents minimal, but persistent, public health expenses. Based on the identified determinants, the Ethiopian federal ministry of health and other stakeholders should pay special attention to the locations designated as hot spots for maternal and child health service enhancement to promote the consumption of iron-rich meals among children aged 6-23 months.


Asunto(s)
Población Negra , Lactancia Materna , Fenómenos Fisiológicos Nutricionales del Lactante , Hierro de la Dieta , Humanos , Lactante , Suplementos Dietéticos , Etiopía , Análisis Multinivel , Análisis Espacial , Hierro de la Dieta/administración & dosificación
2.
J Agric Food Chem ; 71(49): 19682-19693, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37988651

RESUMEN

Tea (Camellia sinensis) flowers emit a large amount of volatiles that attract pollinators. However, few studies have characterized temporal and spatial variation in tea floral volatiles. To investigate the distribution of volatiles within tea flowers and their variation among opening stages, volatile components from different parts of tea flowers and different opening stages were collected by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. A total of 51 volatile compounds of eight chemical classes were identified in the tea flowers. Volatile compounds were most abundant in tea flowers of the Shuchazao cultivar. Acetophenone, 1-phenylethanol, 2-phenylethanol, and benzyl alcohol were the most abundant volatiles. Terpenes were common in the sepals, and benzoids were common in the stamens. The fatty acid derivatives were mainly distributed in the pistils and receptacles and were less abundant in the petals, sepals, and stamens. During the opening phase of tea flowers, the volatile content increased 12-fold, which mainly stemmed from the increase in benzoids. These results enhance our understanding of the formation of volatiles in tea flowers.


Asunto(s)
Camellia sinensis , Compuestos Orgánicos Volátiles , Camellia sinensis/química , Flores/química , Terpenos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida , Té/química , Compuestos Orgánicos Volátiles/química
3.
J Environ Manage ; 345: 118693, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37598495

RESUMEN

Effects of climate change and nutrient load caused by human activities on lake phytoplankton blooms have attracted much attention globally. However, their roles and synergistic effects on phytoplankton biomass and community historical succession are not well understood, especially for meso-eutrophic plateau lakes. In this study, a multi-year (1997-2022) monthly dataset including hydro-chemical and meteorological indicators of the meso-eutrophic plateau lake Erhai in China, was used to explore the contributions of climate change and nutrients on phytoplankton biomass variation and community succession. Phytoplankton biomass increased from 1997 to 2006, slowly decreased from 2006 to 2015, then increased again from 2015 to 2022, according to a generalised additive model (GAM). Alongside warming, nitrogen, phosphorus and organic matter are key drivers of long-term interannual variation in phytoplankton biomass and historical succession of the phytoplankton community. The extensive blooms in recent years were strongly associated with both organic matter accumulation and global warming. Phytoplankton biomass in northern and southern districts was greater than in central areas, with Cyanophyta and Pyrrophyta dominating in the north and Chlorophyta prevalent in the south. Since 2015, phytoplankton diversity has increased significantly, and biomass has declined in the southern district but increased markedly in the northern district. Spatial heterogeneity was caused by the spatial distribution of nutrients and the buoyancy regulation capacity of cyanobacteria. The results demonstrate that bloom mitigation responds strongly to nitrogen and phosphorus control in meso-eutrophic lakes, therefore preventing and controlling blooms through nitrogen and phosphorus reduction is still an effective measure. Given the accumulation of organic matter in recent years, synergistic control of organic matter and total nitrogen and phosphorus could effectively reduce the risk of cyanobacterial and dinoflagellate blooms.


Asunto(s)
Cianobacterias , Fitoplancton , Humanos , Fitoplancton/fisiología , Biomasa , Lagos/microbiología , Estaciones del Año , Cianobacterias/fisiología , China , Fósforo/análisis , Nitrógeno/análisis , Eutrofización
4.
Huan Jing Ke Xue ; 43(6): 3118-3127, 2022 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-35686781

RESUMEN

The agricultural non-point source pollution (ANPSP) load in Guangdong province is very large and has a serious impact on the regional ecological environment. Inventory analysis was used to assess and analyze the temporal and spatial variation characteristics of the ANPSP load of Guangdong province during 1999-2019, and the sources of ANPSP were discussed, as well as the relationship between them. The results showed that, during the past 20 years, the total ANPSP pollution loads of Guangdong province decreased by 6.08%, and the pollution loads of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) increased by -11.88%, 4.99%, and 26.17%, respectively. The input intensity of chemical fertilizers and pesticides increased by 112.19% and 60.38%, respectively. The Pearl River Delta had the highest ANPSP loads in Guangdong province, followed by those in northern, western, and eastern Guangdong. Livestock and poultry breeding were the main sources of COD, the total percent fertilizers and livestock and poultry breeding were the main sources of TN, and livestock and poultry breeding and aquaculture were the main sources of TP. In addition, the contribution of pollutants discharged from aquaculture showed an obvious increasing trend. There were certain differences in the pollution sources in different regions. In western Guangdong, northern Guangdong, and eastern Guangdong, livestock and poultry breeding were the main sources of COD and TP, and fertilizer was the main source of TN; by contrast in the Pearl River Delta, aquaculture had become the main source of TN and TP pollution loads. The correlation results showed that the decline in the total ANPSP in Guangdong province was mainly due to the increase in high urbanization rate and the decrease in the proportion of rural population. In general, there were stage changes in the time and differences in spatial characteristics and sources of ANPSP in Guangdong province. A combination of comprehensive treatment and targeted pollution treatment should be adopted, and fertilizer reduction measures and pollution treatment in the aquaculture should be strengthened in an all-around way, focusing on strengthening the treatment of pollution from aquaculture in the Pearl River Delta region and the treatment of rural life pollution in northern Guangdong.


Asunto(s)
Contaminación Difusa , Contaminantes Químicos del Agua , Animales , Análisis de la Demanda Biológica de Oxígeno , China , Monitoreo del Ambiente/métodos , Fertilizantes/análisis , Humanos , Ganado , Nitrógeno/análisis , Contaminación Difusa/análisis , Fósforo/análisis , Aves de Corral , Contaminantes Químicos del Agua/análisis
5.
Microbiol Spectr ; 10(4): e0026022, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35735985

RESUMEN

Thuja sutchuenensis Franch. is an endangered species in southwest China, distributed sporadically in mountainous areas. Soil property and soil fungal community play a crucial role in plant growth and survival. Nevertheless, understanding soil properties and the soil fungal community in the areas where T. sutchuenensis is distributed is extremely limited. Hence, this study collected a total of 180 soil samples from five altitudinal distribution areas (altitudinal gradients) and three vertical depths throughout four horizontal distances from the base of each tree. The results found that altitudinal gradients and vertical depths altered soil properties, including pH, organic matter content, water content, total nitrogen, phosphorus, and potassium, and available nitrogen, phosphorus, and potassium. The fungal alpha diversity indexes (Chao1 and Shannon) and beta diversity were dramatically decreased with elevation. In addition, high altitudes (2,119 m) harbored the highest relative abundance of ectomycorrhizal fungi (27.57%) and the lowest relative abundance of plant-pathogenic fungi (1.81%). Meanwhile, we identified a series of fungal communities, such as Tomentella, Piloderma, Cortinarius, Sebacina, and Boletaceae, that play an essential role in the survival of T. sutchuenensis. The correlation analysis and random forest model identified that water content and total phosphorus showed strong relationships with fungal characteristics and were the primary variables for Zygomycota and Rozellomycota. Collectively, the findings of this integrated analysis provide profound insights into understanding the contrasting responses of T. sutchuenensis soil fungal communities and provide a theoretical basis for T. sutchuenensis habitat restoration and species conservation from multispatial perspectives. IMPORTANCE The present study highlights the importance of fungal communities in an endangered plant, T. sutchuenensis. Comparative analysis of soil samples in nearly all extant T. sutchuenensis populations identified that soil properties, especially soil nutrients, might play critical roles in the survival of T. sutchuenensis. Our findings prove that a series of fungal communities (e.g., Tomentella, Piloderma, and Cortinarius) could be key indicators for T. sutchuenensis survival. In addition, this is the first time that large-scale soil property and fungal community investigations have been carried out in southwest China, offering important values for exploring the distribution pattern of regional soil microorganisms. Collectively, our findings display a holistic picture of soil microbiome and environmental factors associated with T. sutchuenensis.


Asunto(s)
Basidiomycota , Micobioma , Micorrizas , Thuja , Tracheophyta , Hongos , Nitrógeno , Fósforo , Plantas , Potasio , Suelo/química , Microbiología del Suelo , Agua
6.
Cancer Inform ; 20: 11769351211028194, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34285460

RESUMEN

BACKGROUND: Noncommunicable diseases (NCDs) like cancer are posing a challenge in the health system especially in low- and middle-income countries (LMICs). In South Africa, cancer is under-reported due to the lack of a comprehensive cancer surveillance system. The limited knowledge on the extent of cancer burden has led to inaccurate allocation of public health resources. The aim of this study was to describe cancer incidence and spatial distribution of cancer cases seen at 3 main public oncology facilities in KwaZulu-Natal. METHODS: In this retrospective study, cases of cancer observed from year 2015 to 2017 were extracted from medical records. The crude incidence rate was estimated for the total cancer cases and for different type of cancer reported over that period. Age-standardised incidence rates (ASR) per 100 000 was calculated per year using age groups and sex according to the district population data of KwaZulu-Natal. The comparisons of cancer diagnosed incidences were made between 11 districts using the ASR. Choropleth spatial maps and Moran's Index were used to assess the ASR cancer spatial distribution along with geographical patterns among the districts. One sample chi-square test was used to assess the significant increase/decrease over time. RESULTS: The study lost numerous cases due to incompleteness. A total of 4909 new cases were diagnosed with cancer during 2015 to 2017, 62% of which were female. Both uMgungundlovu and eThekwini districts had the highest ASR among district municipalities of KwaZulu-Natal for both male and female (83.6 per 100 000 per men year for men, 158.2 per 100 000 women per year, and 60.1 per 100 000 men per year and 96.9 per 100 000 women per year, respectively). Random distribution of reported cancer cases in KwaZulu-Natal was observed with a high concentration being in and around 2 metropolitan districts. Spatial variation showed a significant difference from year to year between the districts with the random spatial distribution. Overall, there was a significant decline of cancer incidences observed from 2015 to 2017 (P < .05) in the province. CONCLUSION: The overall cancer incidence in the study shows that female cancers (breast and cervical) are still on the rise and still need to be given priority as they were most prevalent in KwaZulu-Natal. Spatial analysis (choropleth maps) was used to show a pattern of higher concentration of cancer incidence in the north-western parts of the province.

7.
Huan Jing Ke Xue ; 41(2): 734-742, 2020 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-32608732

RESUMEN

Spatial and temporal characteristics of release fluxes of sediment nitrogen (N) and phosphorus (P) were investigated in the high-risk period of algal blooms in Lake Erhai. Moreover, the influence factors were examined. Results show that the release flux of N and P increased in recent years, exhibiting a clear increase in the period from 2009 to 2013, and a slight increase in the period since 2013. The release flux of dissolved total nitrogen (DTN) ranged between 11.71-14.15 mg·(m2·d)-1, within which the release flux of dissolved organic nitrogen (DON) and dissolved inorganic nitrogen (DIN) were 6.39-8.42 mg·(m2·d)-1 and 5.31-5.73 mg·(m2·d)-1, accounting for 58% and 42% of the DTN, respectively. The release flux of dissolved total phosphorus (DTP) ranged between 0.11-0.14 mg·(m2·d)-1, within which the release flux of dissolved organic phosphorus (DOP) and dissolved inorganic phosphorus (DIP) were 0.04-0.05 mg·(m2·d)-1 and 0.07-0.09 mg·(m2·d)-1, accounting for 34% and 66% of the DTP, respectively. The distribution of release flux of N showed a decreasing order:south > north > middle, while P was north > middle > south. The release flux of N increased by 17%, 13% and 23%, and the release flux of P increased by 19%, 28%, and 29% in north, middle, and south part of Lake Erhai from 2009 to 2018. Comparing the years 2009, 2013 and 2018, although the contents of N and P were stable, the release flux of N and P in the sediment was enhanced due to increasing pH and decreasing DO. Therefore, the increasing release of nitrogen and phosphorus from sediments, caused by changes in the water environment factors, should be paid attention to for the protection of Lake Erhai.


Asunto(s)
Eutrofización , Lagos/química , Nitrógeno/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , China , Monitoreo del Ambiente , Sedimentos Geológicos/química , Análisis Espacio-Temporal
8.
Huan Jing Ke Xue ; 40(4): 1779-1787, 2019 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-31087919

RESUMEN

Construction of cascade reservoirs in Lancang River had a certain influence on the ecological water environment of the basin, dividing the water into natural reaches and reservoir reaches. To explore the impact of the cascade reservoirs on the ecological environment, the nutrient and the chlorophyll a distribution data were measured in the natural reaches, reservoir reaches, and tributaries in June 2017. The results showed that the TN ranged from 0.37 to 1.22 mg·L-1, with an average of 0.70 mg·L-1, and the TP ranged from 0.01 to 0.19 mg·L-1, with an average of 0.04 mg·L-1. One-way ANOVA analysis showed significant spatial differences in the TN, with the TN concentration following the order tributaries > reservior reaches > natural reaches. However, the TP concentration did not show a significant trend. The chlorophyll a concentration varied from 2.6 to 10.2 µg·L-1, with a mean of 5.8 µg·L-1. Pearson correlation analysis showed significant relationships between the chlorophyll a concentration and the TP, water temperature, and Zeu/Zmix. The relationship between chlorophyll a and Zeu/Zmix was particularly significant, which indicated the Zeu/Zmix caused by thermal stratification may be the key factor influencing the growth of phytoplankton.


Asunto(s)
Clorofila A/análisis , Monitoreo del Ambiente , Ríos/química , China , Nitrógeno/análisis , Fósforo/análisis
9.
Huan Jing Ke Xue ; 40(2): 590-602, 2019 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-30628321

RESUMEN

It is of great significance to investigate the spatio-temporal variation in nitrogen and phosphorus nutrients as a mechanism for controlling the sudden increase of algae in eutrophic water. Based on the geostatistical analysis, we studied the sources and occurring forms of nitrogen and phosphorus in different areas of Lake Taihu-a large shallow and eutrophic lake in China. We also examined the spatial distribution of the type of nutrient restriction and its reason by monitoring the sites seasonally from August 2014 to May 2015. The results showed that:① The concentrations of soluble nitrogen and phosphorus were higher in the winter than in other seasons, and they gradually decreased spatially from the northwest to southeast. The concentrations of particulate nitrogen, phosphorus, and chlorophyll a were highest in the summer, and the high-concentration regions in the winter and other seasons were located in the southern and northwestern parts of the lake, respectively. ② The composition of nitrogen and phosphorus in algae-and macrophyte-dominated regions changed substantially with the seasonal change. The algae-dominated regions were dominated by nitrate nitrogen and organic phosphorus in the winter and particulate nitrogen and phosphorus during the other seasons. However, the macrophyte-dominated region was dominated by particulate nitrogen and phosphorus in the winter and ammonia, organic nitrogen, and phosphorus during the other seasons. ③ The ratios of total nitrogen to total phosphorus in the algae-dominated region were greater than 16:1 in the autumn and winter but less than 16:1 in the summer and spring. Meanwhile, the ratios of total nitrogen to total phosphorus in the macrophyte-dominated region increased from less than 16:1 in the autumn and winter to more than 16:1 in the summer and spring. In the algae-dominated region, the spatial variation in the dissolved total nitrogen to total phosphorus ratio was consistent with the ratio of total nitrogen to total phosphorus. In the macrophyte-dominated region, the dissolved total nitrogen to total phosphorus ratio increased from less than 16:1 in the autumn to more than 16:1 in the summer, winter, and spring. The temporal and spatial variation in the ratio of particulate nitrogen to phosphorus was not significant (P>0.05), and this ratio was less than and greater than 16 in algae-and macrophyte-dominated regions, respectively.


Asunto(s)
Monitoreo del Ambiente , Lagos/química , Nitrógeno/análisis , Fósforo/análisis , China , Clorofila A/análisis , Eutrofización , Estaciones del Año , Análisis Espacio-Temporal
10.
Biol Trace Elem Res ; 189(2): 354-360, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30167960

RESUMEN

Selenium is an important nutrient for humans and livestock. Soil selenium concentration in the world is highly variable; deficiency and toxicity occur in populations living short distance apart. Knowledge of Se concentrations in humans and the environments, especially because the range for toxicity and deficiency is narrow, is important for effective intervention. Dietary data and serum samples were collected from children (n = 555) 69-78 months old from rural villages of the Amhara Region, Ethiopia. In addition, information on the socio-demography of households was collected. Serum Se was analyzed by inductively coupled plasma mass spectrometer. Almost all (90.3%) of participants reported eating grain, roots, or tubers 24 h preceding the survey followed by legumes, nuts, and seeds (64.6%). Consumption of animal source foods was very low (4.6%). Compared to children from the western part of the region, children from eastern Amhara had higher dietary diversity score (2.1 ± 0.9 vs 1.8 ± 0.7; p < 0.001).The median serum Se concentration was 70.6 µg/l (IQR 48.2, 96.6). Selenium inadequacy (serum Se < 70 µg/l) was detected in 49.1% of children. However, the distribution had an important geographical pattern across administrative zones. Children from the western part of the Amhara Region were highly deficient (up to 91.1% prevalence), while there was little or no Se deficiency in children from the eastern part of the region. Serum Se level exhibited an important spatial variation in the Amhara Region, Ethiopia. Further studies investigating contributing factors for the variation such as soil characteristics and Se concentration in staple crops are needed.


Asunto(s)
Selenio/sangre , Niño , Preescolar , Dieta , Etiopía , Femenino , Humanos , Masculino , Factores Socioeconómicos , Encuestas y Cuestionarios
11.
PeerJ ; 6: e6069, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30564524

RESUMEN

Primate species have been increasingly threatened by legal and illegal trade in China, mainly for biomedical research or as pets and traditional medicine, yet most reports on trade from China regard international trade. To assess a proxy for amount of national primate trades, we quantified the number of reports of native primate species featuring in unique web news reports from 2000 to 2017, including accuracy of their identification, location where they were confiscated or rescued, and their condition upon rescue. To measure temporal trends across these categories, the time span was divided into three sections: 2000-2005, 2006-2011 and 2012-2017. A total of 735 individuals of 14 species were reported in 372 news reports, mostly rhesus macaques (n = 165, 22.5%, Macaca mulatta) and two species of slow lorises (n = 487, 66.3%, Nycticebus spp.). During the same period, live individuals of rhesus macaques were recorded 206 times (70,949 individuals) in the Convention on International Trade in Endangered Species of Wild Fauna and Flora Trade Database, whereas slow lorises were only recorded four times (nine individuals), indicating that the species originated illegally from China or were illegally imported into China. Due to their rescued locations in residential areas (n = 211, 56.7%), most primates appeared to be housed privately as pets. A higher proportion of 'market' rescues during 2006-2011 (χ2 = 8.485, df = 2, p = 0.014), could be partly attributed to an intensive management on wildlife markets since the outbreak of severe acute respiratory syndrome (SARS) in 2003. More than half (68.3%, 502 individuals) of the primate individuals were unhealthy, injured or dead when rescued. Thus, identification and welfare training and capacity-building should be provided to husbandry and veterinary professionals, as well as education to the public through awareness initiatives. The increase in presence of some species, especially slow lorises, with a declining population in restricted areas, also suggests the urgent need for public awareness about the illegal nature of keeping these taxa as pets.

12.
Environ Monit Assess ; 190(10): 604, 2018 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-30244370

RESUMEN

Jordan relies heavily on reservoirs building and development to cope with water supply challenges, where monitoring and assessment of reservoir water quality are critically important for the sustainable use of these water supplies. Mujib Dam is an important water supply source in central western Jordan. Evaluation of water quality parameters and their spatial distributions (vertical and horizontal) showed near-neutral pH values with nearly similar values from surface to bottom. The vertical profile of DO and TDS in the dammed reservoir showed slight decreasing trends with increasing depth. Although Ca, Mg, Na, and K concentrations varied slightly with depths, their variations showed no trends. Similarly, the vertical and horizontal distribution patterns of Cl, SO4, HCO3, NO3, and PO4 in Mujib reservoir water showed insignificant variations in surface water layer and relatively unchanged values or decreasing trends through the water column. Higher values of TN have been observed, especially in the western part, suggesting that agricultural activities and livestock farming in the upstream catchment are impacting water quality. Results revealed that weathering and dissolution of rocks are the major source of water chemistry. The majority of trace metal levels (Cd, Cr, Cu, Fe, Mn, Pb, Zn, Co, Ni, Sr, and B) in water showed relatively similar surface and bottom values. The concentrations of COD and BOD5 in surface water were relatively low with higher concentrations observed in the northwestern corner, coincided with higher levels of chlorophyll a. The average ratio of TN to TP in surface water suggests that phosphorus is the limiting factor for the algal blooms, whereas the average chlorophyll a level in surface water indicates oligo-mesotrophic water.


Asunto(s)
Agua Potable/química , Monitoreo del Ambiente/métodos , Fósforo/análisis , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua , Agricultura/métodos , Clorofila A/análisis , Agua Potable/análisis , Eutrofización , Jordania , Abastecimiento de Agua
13.
Ying Yong Sheng Tai Xue Bao ; 29(6): 1893-1901, 2018 Jun.
Artículo en Chino | MEDLINE | ID: mdl-29974699

RESUMEN

Based on a grid (25 m X 25 m) equidistant sampling, the spatial variability of pH, organic matter, total nitrogen, available phosphorus, CEC and three typical heavy metal elements Cd, As and Pb in soil tillage layer (0-20 cm) were analyzed by using GIS and Geostatistics in the paddy field of 3.56 hm2 in Beishan Town, Changsha County, Hunan Province. The results showed that soil pH value and Pb content showed weak variation, and other indexes showed moderate variation. The order of variation was following available phosphorus > Cd > total nitrogen > organic matter > CEC > As > Pb > pH. Results of the semi-variance test showed that the best fitting model of the semi-variance function of organic matter, available phosphorus and As was exponential, and the best semi-variance function of pH, total nitrogen, CEC, Cd, Pb was spherical. All the indicators had a strong spatial correlation except for CEC, which showed moderate spatial correlation. Kriging interpolation analysis showed that pH, total nitrogen, CEC, Pb were plaque distribution, while organic matter, available phosphorus, Cd and As were block and banded distribution. Vegetation, topography and human activities were the main factors driving the variation of soil nutrients and heavy metals in the study area. The correlation between soil nutrients and heavy metals content was significant, among which pH and organic matter, Cd and Pb reached a very significant correlation level.


Asunto(s)
Monitoreo del Ambiente , Sistemas de Información Geográfica , Metales Pesados/análisis , Oryza , China , Fósforo , Suelo , Contaminantes del Suelo
14.
Environ Monit Assess ; 190(5): 314, 2018 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-29705824

RESUMEN

Coastal lagoon ecosystems are vulnerable to eutrophication, which leads to the accumulation of nutrients from the surrounding watershed over the long term. However, there is a lack of information about methods that could accurate quantify this problem in rapidly developed countries. Therefore, various statistical methods such as cluster analysis (CA), principal component analysis (PCA), partial least square (PLS), principal component regression (PCR), and ordinary least squares regression (OLS) were used in this study to estimate total organic matter content in sediments (TOM) using other parameters such as temperature, dissolved oxygen (DO), pH, electrical conductivity (EC), nitrite (NO2), nitrate (NO3), biological oxygen demand (BOD), phosphate (PO4), total phosphorus (TP), salinity, and water depth along a 3-km transect in the Gomishan Lagoon (Iran). Results indicated that nutrient concentration and the dissolved oxygen gradient were the most significant parameters in the lagoon water quality heterogeneity. Additionally, anoxia at the bottom of the lagoon in sediments and re-suspension of the sediments were the main factors affecting internal nutrient loading. To validate the models, R2, RMSECV, and RPDCV were used. The PLS model was stronger than the other models. Also, classification analysis of the Gomishan Lagoon identified two hydrological zones: (i) a North Zone characterized by higher water exchange, higher dissolved oxygen and lower salinity and nutrients, and (ii) a Central and South Zone with high residence time, higher nutrient concentrations, lower dissolved oxygen, and higher salinity. A recommendation for the management of coastal lagoons, specifically the Gomishan Lagoon, to decrease or eliminate nutrient loadings is discussed and should be transferred to policy makers, the scientific community, and local inhabitants.


Asunto(s)
Monitoreo del Ambiente , Contaminación Química del Agua/análisis , Análisis de la Demanda Biológica de Oxígeno , Ecosistema , Eutrofización , Irán , Análisis Multivariante , Nitratos/análisis , Oxígeno/análisis , Fósforo/análisis , Salinidad , Contaminación Química del Agua/estadística & datos numéricos , Calidad del Agua/normas
15.
Mar Pollut Bull ; 122(1-2): 139-148, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28669479

RESUMEN

Aliphatic hydrocarbons (AHs), biomarker and polycyclic aromatic hydrocarbons (PAHs) concentrations of surface water and sediment samples collected from Yellow River Estuary and adjacent coastal area in China were measured to determine their spatial distributions, analyze their sources and evaluate the ecological risk of PAHs in the water-sediment system. The spatial distributions of n-alkane in sediments are mainly controlled by the mixing inputs of terrigenous and marine components. In comparison with AHs, the total concentrations of Σ16PAHs in surface sediments from a transect of the offshore area were noticeably higher than that of the riverine and estuary areas. Additionally, the AHs and total PAHs concentrations all indicated an overall pattern of a seaward decrease. The PAHs concentrations during the dry season (mainly in the form of dissolved phase) were higher than that of PAHs (mainly dissolved phase and particulate phase form) in the flooding season. In comparison with global concentration levels of PAHs, the level of PAHs in suspended particulate matter and sediments from the Yellow River Estuary was lower than those from other countries, while the concentration of PAHs in the dissolved phase were in the middle range. Petroleum contamination, mainly from oil exploration and discharge of pollutants from rivers, was the main source of n-alkanes. The PAHs in the river were mostly of petrogenic origin, while those in the estuarial and marine areas originated mainly from pyrogenic sources. The results of the toxicology assessment suggested that the PAHs in sediments from Yellow River Estuary and adjacent coastal area exhibited a low potential eco-toxicological contamination level.


Asunto(s)
Petróleo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Contaminantes Químicos del Agua/toxicidad , China , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos , Hidrocarburos Policíclicos Aromáticos/análisis , Ríos , Agua , Contaminantes Químicos del Agua/análisis
16.
Environ Monit Assess ; 188(10): 565, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27629555

RESUMEN

Bobcats (Lynx rufus) are wide-ranging mammals found throughout the continental USA. As carnivores near the top of their food chain, bobcats would seem to be a useful bioindicator of metal pollution in terrestrial environments. However, there is very limited research on bobcats in toxicology studies. Here, we offer the first analysis of metal (copper, selenium, silver, and zinc) contaminants in the livers of wild bobcats. Liver tissues from 120 adult bobcats (i.e., estimated to be ≥1 year old) were collected from 2003 to 2006 at four sites in Georgia and Florida, USA that experienced relatively similar levels of human disturbance. We found no differences in metal concentrations between males and females. At two of the sites sampled over three consecutive years, there was substantial year-to-year variation in the concentrations of Cu, Se, and Zn. We also documented some variation between sites, but only between sites sampled in different years, which may reflect additional temporal, rather than spatial, variation. Concentrations of Cu and Ag were significantly positively correlated with one another, as were concentrations of Se and Zn. Contrary to expectation, there were no significant relationships between body weight and metal concentrations. Finally, comparison with results from previous metal toxicology studies of nine-banded armadillos (Dasypus novemcinctus) and Virginia opossums (Didelphis virgianus), collected from the same sites during the same years, showed differential patterns of accumulation across species, suggesting that ecological lifestyle is an important influence on metal accumulation. This study provides reference levels of metal contaminants in the liver of bobcats as well as insight into metal accumulation in a top level carnivore.


Asunto(s)
Cobre/análisis , Monitoreo del Ambiente , Hígado/química , Lynx/metabolismo , Selenio/análisis , Plata/análisis , Zinc/análisis , Animales , Contaminación Ambiental/análisis , Femenino , Florida , Cadena Alimentaria , Masculino , Sudeste de Estados Unidos
17.
Ying Yong Sheng Tai Xue Bao ; 27(4): 1211-1220, 2016 Apr 22.
Artículo en Chino | MEDLINE | ID: mdl-29732778

RESUMEN

Soil phosphorus is an important indicator to measure the soil fertility, because the content of soil phosphorus has an important effect on physical and chemical properties of soil, plant growth, and microbial activity in soil. In this study, the soil samples collecting and indoor analysis were conducted in Zhoukou City located in the flooded area of the Yellow River. By using GIS combined with geo-statistics, we tried to analyze the spatial variability and content distribution of soil total phosphorus (TP) and soil available phosphorus (AP) in the study area. Results showed that TP and AP of both soil layers (0-20 cm and 20-40 cm) were rich, and the contents of TP and AP in surface layer (0-20 cm) were higher than in the second layer (20-40 cm). TP and AP of both soil layers exhibited variation at medium level, and AP had varied much higher than TP. TP of both layers showed medium degree of anisotropy which could be well modeled by the Gaussian model. TP in the surface layer showed strong spatial correlation, but that of the second layer had medium spatial correlation. AP of both layers had a weaker scope in anisotropy which could be simulated by linear model, and both soil layers showed weaker spatial correlations. TP of both soil layers showed a slowly rising change from southwest to northeast of the study area, while it gradually declined from northwest to southeast. AP in soil surface layer exhibited an increase tendency firstly and then decrease from southwest to the northeast, while it decreased firstly and then increased from southeast to the northwest. AP in the second soil layer had an opposite change in the southwest to the northeast, while it showed continuously increasing tendency from northwest to the southeast. The contents of TP and AP in the surface layer presented high grades and the second layer of TP belonged to medium grade, but the second layer of AP was in a lower grade. The artificial factors such as land use type, cropping system, irrigation and fertilization were the main factors influencing the distribution and spatial variation of soil phosphorus in this area.


Asunto(s)
Fósforo/análisis , Suelo/química , China , Inundaciones , Sistemas de Información Geográfica , Ríos , Análisis Espacial
18.
Complement Ther Med ; 23(3): 439-50, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26051580

RESUMEN

Despite the recognition for rising consumption rate of traditional medicine (TRM) in health and spatio-medical literature in the global scale, the impact of location in traditional therapy use has been explored least in Ghana. This paper analysed the role of spatial variation in TRM use in Kumasi Metropolis and Sekyere South District of Ashanti Region, Ghana. A retrospective cross-sectional and place-based survey was conducted in a representative sample (N=324) selected through systematic random sampling technique. Structured interviewer-administered questionnaires were espoused as the main research instruments. Data were analysed with Pearson's Chi-square and Fisher's exact tests from the Predictive Analytics Software (PASW) version 17.0. The study found that over 86% reported TRM use. Whilst majority (59.1%) of the respondents had used TRM two or more times within the last 12 months, biologically-based therapies and energy healing were common forms of TRM accessed. Although, the use of TRM did not vary (p>0.05), knowledge about TRM, modalities of TRM and the sources of TRM differed significantly across geographically demarcated rural and urban splits (p<0.005). The study advances our understanding of the spatial dimensions as regards TRM utilisation.


Asunto(s)
Medicinas Tradicionales Africanas/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Adulto , Estudios Transversales , Femenino , Ghana/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Análisis Espacial , Adulto Joven
19.
Mar Pollut Bull ; 89(1-2): 390-406, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25440897

RESUMEN

The present study gives a summary using state-of-the-art technology to monitor Posidonia oceanica and Mytilus galloprovincialis as bioindicators of the pollution of the Mediterranean littoral with trace elements (TEs), and discusses their complementarity and specificities in terms of TE bioaccumulation. Furthermore, this study presents two complementary indices, the Trace Element Spatial Variation Index (TESVI) and the Trace Element Pollution Index (TEPI): these indices were shown to be relevant monitoring tools since they led to the ordering of TEs according to the overall spatial variability of their environmental levels (TESVI) and to the relevant comparison of the global TE pollution between monitored sites (TEPI). In addition, this study also discusses some underestimated aspects of P. oceanica and M. galloprovincialis bioaccumulation behaviour, with regard to their life style and ecophysiology. It finally points out the necessity of developing consensual protocols between monitoring surveys in order to publish reliable and comparable results.


Asunto(s)
Alismatales/química , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Mytilus/química , Contaminantes Químicos del Agua/análisis , Animales , Agua de Mar , Oligoelementos/análisis
20.
J Vector Ecol ; 38(2): 229-36, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24581350

RESUMEN

Nearly 30% of emerging infectious disease events are caused by vector-borne pathogens with wildlife origins. Their transmission involves a complex interplay among pathogens, arthropod vectors, the environment and host species, and they pose a risk for public health, livestock and wildlife species. Examining habitat associations of vector species known to transmit infectious diseases, and quantifying spatio-temporal dynamics of mosquito vector communities is one aspect of the holistic One Health approach that is necessary to develop effective control measures. A survey was conducted from May to August, 2010 of the abundance and diversity of mosquito species occurring in the mixed-grass prairie habitat of the Smoky Hills of Kansas. This region is an important breeding ground for North America's grassland nesting birds and, as such, it could represent an important habitat for the enzootic amplification cycle of avian malaria and infectious encephalitides, as well as spill-over events to humans and livestock. A total of 11 species, belonging to the three genera Aedes, Anopheles, and Culex, was collected during this study. Aedes nigromaculis, Ae. sollicitans, Ae. taeniorhynchus, Culex salinarius, and Cx. tarsalis accounted for 98% of the collected species. Multiple linear regression models suggested that mosquito abundances in the grasslands of the central Great Plains were explained by meteorological and environmental variables. Temporal dynamics in mosquito abundances were well supported by models that included maximum and minimum temperature indices (adjusted R(2) = 0.73). Spatial dynamics of mosquito abundances were best explained by a model containing the following environmental variables (adjusted R(2) =0.37): ground curvature, topographic wetness index, distance to woodland, and distance to road. The mosquito species we detected are known vectors for infectious encephalitides, including West Nile virus. Understanding the microhabitat characteristics of these mosquito species in a grassland ecosystem will aid in the control and management of these disease vectors.


Asunto(s)
Culicidae/fisiología , Análisis Espacio-Temporal , Animales , Kansas
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