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1.
J Environ Manage ; 289: 112432, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33838466

RESUMEN

Highway runoff impacts urban and natural ecosystems negatively. A financing model, that is economically feasible and accepted by all stakeholders, has been a limitation for the implementation of pollution control measures. A case-study on a 279-km Portuguese Highway is presented as a basis for a co-financing model. Runoff pollution load was estimated for quality indicators (TSS, COD, Zn, Cu, Pb), and the total cost of infiltration trenches, sand filters, bioretention filters, wet basins, dry basins and constructed wetlands systems was computed for four catchment scenarios. The effect of the equivalent catchment size and system type on the total cost was evaluated. The users 'Willingness to Pay' (defined as pay-per-user and availability to participate actively and financially) was assessed through a survey (1192 responses). A proposed co-financing model suggests that citizens will participate up to 36.8% of the constructed wetlands cost. This multidisciplinary approach results in potential outcomes that include a legal framework, proven technical solutions, and users' environmental responsibility.


Asunto(s)
Movimientos del Agua , Contaminantes Químicos del Agua , Ecosistema , Monitoreo del Ambiente , Contaminación Ambiental , Lluvia , Contaminantes Químicos del Agua/análisis , Humedales
2.
J Environ Manage ; 289: 112507, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33839610

RESUMEN

This study proposes a community rainwater harvesting (RWH) system as an alternative water supply solution for Paikgacha, a water-scarce coastal urban area in Bangladesh. Although individual household-based RWH systems have been implemented in many areas in Bangladesh, to date, no study has been conducted designing a community RWH system and assessing its reliability and financial feasibility. This study employs historical observed and available climate model predicted future rainfall data into stormwater management model (SWMM) for rainfall-runoff simulation of the community RWH, and compares SWMM's performance with rational formula based estimation. We then calculate volumetric and time reliability of the proposed system and assess its financial viability. We observe good agreement in reliability curves generated by SWMM and rational formula-based model. Under the historical rainfall scenario, our proposed community RWH shows up to 99% reliability for 100 L per day household demand, given that proper community size and storage tank size are chosen. Predicted rainfall pattern of 2041-2070 period shows similar reliability-tank size relation to that of historical observed rainfall; however, predicted high precipitation intensity during 2021-2040 and 2071-2100 seem to assist the system in attaining higher reliability. Cost-benefit analysis indicates the financial viability of the proposed system. Finally, we develop a nomograph incorporating interactive factors of RWH, which would ease decision making by the policymakers regarding the implementation of community RWH.


Asunto(s)
Cambio Climático , Lluvia , Bangladesh , Conservación de los Recursos Naturales , Estudios de Factibilidad , Reproducibilidad de los Resultados , Abastecimiento de Agua
3.
Water Sci Technol ; 83(8): 1932-1945, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33905363

RESUMEN

Permeable asphalt pavement types are generally selected according to local traffic volume and rainfall intensity. This study focuses on the design of the pavement drainage asphalt pavement combination scheme by analyzing the rainfall characteristics of five representative cities in North China. Furthermore, nine kinds of drainage pavement scheme applicable to Beijing are proposed. To this end, the permeable function design analysis, as well as the bearing capacity design analysis of permeable asphalt pavement, was carried out with the help of storm runoff simulation software SWMM5.1 and pavement structure analysis software BISAR3.0, respectively. The results indicate that the minimum total design thickness of permeable surface layer and permeable basic layer meeting the requirements of road drainage in this region is 170 mm, and the nine drainage pavement schemes meet the specification requirements.


Asunto(s)
Lluvia , Movimientos del Agua , Beijing , China , Ciudades
4.
Artículo en Inglés | MEDLINE | ID: mdl-33805028

RESUMEN

In southern China, the growing period of rice is synchronized with the rainy period, and the loss of nutrients (such as nitrogen) due to unreasonable irrigation and drainage, along with rainfall and runoff, has become the main source of agricultural nonpoint source pollution. The laws of runoff and nitrogen loss in paddy fields under different irrigation and drainage modes are not clear. In this study, field experiments were adopted to observe the runoff and nitrogen loss under typical rainfall and throughout the whole growth period. The results showed that, compared with the traditional irrigation and drainage mode, the controlled irrigation and drainage mode reduced the drainage of two typical rainfall processes by 47.5% and 31.3% and the peak drainage by 38.9% and 14.4%. Compared with those under the traditional irrigation and drainage mode, the average concentrations of total nitrogen, nitrate nitrogen, and ammonium nitrogen under the controlled irrigation and drainage mode were reduced by 22.2%, 22.7%, and 27.8%, respectively, during the whole rainfall process on July 21 and were decreased by 27.1%, 11.4%, and 25.6%, respectively, on August 25. In irrigated rice areas, under the controlled irrigation and drainage mode, drainage was reduced after two intercepts through paddy fields and drainage ditches. The nitrogen concentration in the drainage ditch decreased due to the increase in retention time and the effect of the ditch and field wetland. Compared with the traditional irrigation and drainage mode, the total nitrogen, nitrate nitrogen, and ammonium nitrogen loads of the controlled irrigation and drainage mode were reduced by 69.8%, 65.3%, and 69.7%, respectively.


Asunto(s)
Nitrógeno , Oryza , Riego Agrícola , Agricultura , China , Nitrógeno/análisis , Fósforo/análisis , Lluvia
5.
Environ Monit Assess ; 193(5): 263, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33847840

RESUMEN

Rainfall is a climatic variable that dictates the daily rhythm of urban areas in Northeastern Brazil (NEB) and, therefore, understanding its dynamics is fundamental. The objectives of the study were (i) to validate the CHELSA product with data in situ, (ii) assess the spatial-temporality of the rains, and (iii) assess the trends and socio-environmental implications in the Metropolitan Region of Maceió (MRM). The monthly rainfall data observed between 1960 and 2016 were flawed and were filled with the imputation of data. These series were subjected to descriptive and exploratory statistics, statistical indicators, and the Mann-Kendall (MK) and Pettitt tests. CHELSA product was validated for MRM, and all stations obtained satisfactory determination coefficients (R2) and Pearson correlation (r). The standard error of the estimate (SEE), root mean square error (RMSE), and mean absolute error (MAE) were satisfactory. The highest annual rainfall accumulated occurred near the Mundaú and Manguaba lagoons. The Pettitt test identified that abrupt changes occur in El Niño and La Niña years (strong and weak). The monthly rain boxplots showed high variability in the rainy season (April-July). Outliers have been associated with extreme rainfall at MRM. The drought period was 5 months in all MRM seasons, except in Satuba and Pilar. The Mann-Kendall test and the Sen method showed a tendency for a significant increase in rainfall in Satuba and not significant in the Pilar, while in the others, there was a tendency for a decrease in rainfall. The MRM rainfall depends on physiographic factors, multiscale meteorological systems, and the coastal environment. These results will assist in planning conservationist practices, especially in areas of socio-environmental vulnerability.


Asunto(s)
Monitoreo del Ambiente , Lluvia , Brasil , El Niño Oscilación del Sur , Estaciones del Año
6.
Water Res ; 197: 117076, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33819662

RESUMEN

Stormwater runoff pollution has become a key environmental issue in urban areas. Reliable estimation of stormwater pollutant discharge is important for implementing robust water quality management strategies. Even though significant attempts have been undertaken to develop water quality models, deterministic approaches have proven inappropriate as they do not address the variability in stormwater quality. Due to the random nature of rainfall characteristics and the differences in catchment characteristics, it is difficult to generate the runoff pollutographs to a desired level of certainty. Bayesian hierarchical modelling is an effective tool for developing complex models with a large number of sources of variability. A Bayesian model does not look for a single value of the model parameters, but rather determines a distribution of the model parameters from which all inference is drawn. This study introduces a Bayesian hierarchical linear regression model to describe a catchment specific runoff pollutograph incorporating the associated uncertainties in the model parameters. The model incorporates catchment and rainfall characteristics including the effective impervious area, time of concentration, rain duration, average rainfall intensity and the antecedent dry period as the contributors to random effects.


Asunto(s)
Movimientos del Agua , Contaminantes Químicos del Agua , Teorema de Bayes , Ciudades , Monitoreo del Ambiente , Lluvia , Contaminantes Químicos del Agua/análisis
7.
Sci Rep ; 11(1): 8358, 2021 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-33863938

RESUMEN

Climate seems to influence the spread of SARS-CoV-2, but the findings of the studies performed so far are conflicting. To overcome these issues, we performed a global scale study considering 134,871 virologic-climatic-demographic data (209 countries, first 16 weeks of the pandemic). To analyze the relation among COVID-19, population density, and climate, a theoretical path diagram was hypothesized and tested using structural equation modeling (SEM), a powerful statistical technique for the evaluation of causal assumptions. The results of the analysis showed that both climate and population density significantly influence the spread of COVID-19 (p < 0.001 and p < 0.01, respectively). Overall, climate outweighs population density (path coefficients: climate vs. incidence = 0.18, climate vs. prevalence = 0.11, population density vs. incidence = 0.04, population density vs. prevalence = 0.05). Among the climatic factors, irradiation plays the most relevant role, with a factor-loading of - 0.77, followed by temperature (- 0.56), humidity (0.52), precipitation (0.44), and pressure (0.073); for all p < 0.001. In conclusion, this study demonstrates that climatic factors significantly influence the spread of SARS-CoV-2. However, demographic factors, together with other determinants, can affect the transmission, and their influence may overcome the protective effect of climate, where favourable.


Asunto(s)
/transmisión , Clima , Modelos Teóricos , Presión Atmosférica , /patología , Humanos , Humedad , Densidad de Población , Prevalencia , Lluvia , Temperatura
8.
Environ Monit Assess ; 193(4): 241, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33791871

RESUMEN

Stormwater runoff is a major concern in urban areas which is mostly the result of vast urbanization. To reduce urban stormwater runoff and improve water quality, low impact development (LID) is used in urban areas. Therefore, it is vital to find the optimal combination of LID controls to achieve maximum reduction in both stormwater runoff and pollutants with optimal cost. In this study, a simulation-optimization model was developed by linking the EPA Storm Water Management Model (SWMM) to the Multi-Objective Particle Swarm Optimization (MOPSO) using MATLAB. The coupled model could carry out multi-objective optimization (MOO) and find potential solutions to the optimization objectives using the SWMM simulation model outputs. The SWMM model was developed using data from the BUNUS catchment in Kuala Lumpur, Malaysia. The total suspended solids (TSS) and total nitrogen (TN) were selected as pollutants to be used in the simulation model. Vegetated swale and rain garden were selected as LID controls for the study area. The LID controls were assigned to the model using the catchment characteristics. The target objectives were to minimize peak stormwater runoff, TSS, and TN with the minimum number of LID controls applications. The LID combination scenarios were also tested in SWMM to identify the best LID types and combination to achieve maximum reduction in both peak runoff and pollutants. This study found that the peak runoff, TSS, and TN were reduced by 13%, 38%, and 24%, respectively. The optimal number of LID controls that could be used at the BUNUS catchment area was also found to be 25.


Asunto(s)
Monitoreo del Ambiente , Lluvia , Malasia , Control de Calidad , Urbanización , Movimientos del Agua
9.
Sci Adv ; 7(10)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33674320

RESUMEN

The COVID-19 (coronavirus disease 2019) pandemic has resulted in a marked slowdown in greenhouse gas and aerosol emissions. Although the resulting emission reductions will continue to evolve, this will presumably be temporary. Here, we provide estimates of the potential effect of such short-term emission reductions on global and regional temperature and precipitation by analyzing the response of an Earth System Model to a range of idealized near-term emission pathways not considered in available model intercomparison projects. These estimates reveal the modest impact that temporary emission reductions associated with the COVID-19 pandemic will have on global and regional climate. Our simulations suggest that the impact of carbon dioxide and aerosol emission reductions is actually a temporary enhancement in warming rate. However, our results demonstrate that even large emission reductions applied for a short duration have only a small and likely undetectable impact.


Asunto(s)
Clima , Efecto Invernadero/prevención & control , Aire , Dióxido de Carbono/análisis , Internacionalidad , Lluvia , Temperatura , Factores de Tiempo
10.
Ying Yong Sheng Tai Xue Bao ; 32(3): 1015-1022, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33754568

RESUMEN

The distribution pattern of biological soil crusts (biocrusts) is one of the main factors affecting runoff and sediment yield. The relationship between runoff and sediment yield and biocrusts' distribution pattern is not clear, which hinders understanding the mechanism underlying the effects of biocrusts on runoff and sediment from slopes. To fill the knowledge gap, we investigated the relationship between the landscape indices of three biocrusts' distribution patterns, i.e. zonation, chessboard and random, and the hydraulic parameters, using of simulated rainfall experiments and landscape ecology methods. The results showed that biocrust significantly affected the erosion force of slopes and that its distribution pattern could affect slope erosion dynamics. Compared to bare soil, the presence of biocrusts significantly reduced the runoff velocity (54.6%) and Froude number (67.0%), increased the runoff depth (86.2%) and Darcy-Weisbach resistance coefficient (10.68 times), but did not affect the Reynolds number and runoff power. Expect for the runoff depth, there were significant differences in the hydraulic parameters of the three biocrusts' distribution patterns, with the random pattern having the strongest impacts on the dynamics of slope erosion. Based on factor analysis and cluster analysis, five indices of percentage of patch to landscape area, patch density, landscape shape index, patch cohesion and splitting could be used as the indicators for the distribution characteristics of biocrust patches. The patch cohesion and splitting of biocrust patches were the main distribution pattern indices of the hydrodynamics of surface runoff. As the patches patch cohesion decreased, the splitting increased, which caused the surface runoff velocity increase, the resistance decrease, and the slope erosion became more severe.


Asunto(s)
Lluvia , Suelo , Sedimentos Geológicos , Hidrodinámica
11.
Artículo en Inglés | MEDLINE | ID: mdl-33669684

RESUMEN

Seepage plays a key role in nutrient loss and easily occurs in widely-used contour ridge systems due to the ponding process. However, the characteristics of nutrient loss and its influential factors under seepage with rainfall condition in contour ridge systems are still unclear. In this study, 23 seepage and rainfall simulation experiments are arranged in an orthogonal rotatable central composite design to investigate the role of ridge height, row grade, and field slope on Nitrate (NO3--N) and Orthophosphate (PO4+3-P) losses resulting from seepage in contour ridge systems. In total, three types of NO3--N and PO4+3-P loss were observed according to erosion processes of inter-rill-headward, inter-rill-headward-contour failure, and inter-rill-headward-contour failure-rill. Our results demonstrated that second-order polynomial regression models were obtained to predict NO3--N and PO4+3-P loss with the independent variables of ridge height, row grade, and field slope. Ridge height was the most important factor for nutrient loss, with a significantly positive effect and the greatest contribution (52.35-53.47%). The secondary factor of row grade exerted a significant and negative effect, and was with a contribution of 19.86-24.11% to nutrient loss. The interaction between ridge height and row grade revealed a significantly negative effect on NO3--N loss, whereas interactions among the three factors did not significantly affect PO4+3-P loss. Field slope only significantly affected NO3--N loss. The optimal design of a contour ridge system to control nutrient loss was obtained at ridge height of 8 cm, row grade of 2°, and field slope of 6.5°. This study provides a method to assess and model nutrient loss, and improves guidance to implement contour ridge systems in terms of nutrient loss control.


Asunto(s)
Nitratos , Fosfatos , Nutrientes , Fósforo , Lluvia , Suelo , Movimientos del Agua
12.
Artículo en Inglés | MEDLINE | ID: mdl-33670054

RESUMEN

Cultivated land plays an important role in water and soil loss in earthy/rocky mountainous regions in northern China, however, its response to soil conservation measures and rainfall characteristics are still not fully understood. In the present study, 85 erosive rainfall events in 2011-2019 were grouped into three types, and the responses of runoff and soil loss to soil conservation measures and rainfall regimes on five cultivated plots with different slopes in the upstream catchment of the Miyun Reservoir were evaluated. Results found that mean event runoff depths and soil loss rates on the five plots ranged from 0.03 mm to 7.05 mm and from 0.37 t km-2 to 300.51 t km-2 respectively, depending on rainfall regimes, soil conservation measures, and slope gradients. The high frequency (i.e., 72.94%) rainfall regime A with a short rainfall duration (RD), low rainfall amount (P), and high mean rainfall intensity (Im) yielded a lower runoff depth and higher soil loss rate. Rainfall regime B with a longer RD, and a higher P and Im, however, produced higher a runoff depth and lower soil loss rate. Terraced plots had the highest runoff and soil loss reduction efficiencies of over 96.03%. Contour tillage had comparable sediment reduction efficiency to that of the terraced plots on gentle slopes (gradient less than 11.0%), while its runoff reduction efficiency was less than 13.11%. This study implies that in the Miyun Reservoir catchment and similar regions in the world, contour tillage should be promoted on gentle slopes, and the construction of terraced plots should be given ample consideration as they could greatly reduce water quantity and cause water shortages in downstream catchments.


Asunto(s)
Suelo , Movimientos del Agua , China , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Sedimentos Geológicos , Lluvia
13.
Artículo en Inglés | MEDLINE | ID: mdl-33673170

RESUMEN

Urban evaporation, as an essential part of local water vapor resources in urban areas, has often been underestimated. One possible reason is that the evaporation of urban hardened surfaces is seldom considered and poorly understood in urban evaporation estimation. This study focused on the mechanisms and calculation of evaporation on hardened surfaces in urban areas. Experimental monitoring was used to monitor the processes and characteristics of evaporation on hardened surfaces. Mathematical models based on water quantity constraints were built to calculate evaporation of hardened surfaces. The results showed that: The interception abilities for rainwater and rainfall days of impervious hardened surfaces determine their evaporated water amount, which means no water, no evaporation for the impervious surfaces. The greater evaporation of artificial sprinkling on roads happened in fewer days of rainfall and frost. The evaporation of pervious hardened ground is continuous compared to the impervious surface. Its soil moisture in the sub-layer of permeable concrete decreases periodically with a period of one day. The evaporation of hardened surfaces occupies 16-29% of the total amount of evaporation in the built-up areas in cities. Therefore, the hardened surface evaporation has great significance on the urban hydrological cycle and urban water balance.


Asunto(s)
Suelo , Movimientos del Agua , Ciudades , Modelos Teóricos , Lluvia , Ciclo Hidrológico
14.
Nat Commun ; 12(1): 1824, 2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33758189

RESUMEN

There is an urgent need to synthesize the state of our knowledge on plant responses to climate. The availability of open-access data provide opportunities to examine quantitative generalizations regarding which biomes and species are most responsive to climate drivers. Here, we synthesize time series of structured population models from 162 populations of 62 plants, mostly herbaceous species from temperate biomes, to link plant population growth rates (λ) to precipitation and temperature drivers. We expect: (1) more pronounced demographic responses to precipitation than temperature, especially in arid biomes; and (2) a higher climate sensitivity in short-lived rather than long-lived species. We find that precipitation anomalies have a nearly three-fold larger effect on λ than temperature. Species with shorter generation time have much stronger absolute responses to climate anomalies. We conclude that key species-level traits can predict plant population responses to climate, and discuss the relevance of this generalization for conservation planning.


Asunto(s)
Cambio Climático , Desarrollo de la Planta/fisiología , Plantas/efectos adversos , Dinámica Poblacional/estadística & datos numéricos , Variación Biológica Poblacional/fisiología , Clima , Bases de Datos Factuales , Ecosistema , Modelos Estadísticos , Lluvia , Análisis de Regresión , Temperatura
15.
Int. j. med. surg. sci. (Print) ; 8(1): 1-4, mar. 2021. ilus
Artículo en Inglés | LILACS | ID: biblio-1151626

RESUMEN

The effect of climatological parameter on infectious disease is an interesting issue in clinical epidemiology. Of several parameters, rainfall is reported for its interrelationship with many tropical diseases such as malaria. In this short communication, the authors report the observation on correlation between rainfall and the prevalence of scrub typhus from a tropical endemic country.


El efecto del parámetro climatológico en las enfermedades infecciosas es un tema interesante en la epidemiología clínica. De varios parámetros, se reportan precipitaciones por su interrelación con muchas enfermedades tropicales como el paludismo. En esta breve comunicación, los autores informan de la observación sobre la correlación entre las precipitaciones y la prevalencia del tifus de matorral de un país endémico tropical.


Asunto(s)
Lluvia , Tifus por Ácaros/etiología , Prevalencia , Tailandia , Clima Tropical , Enfermedades Endémicas
16.
An Acad Bras Cienc ; 93(1): e20200198, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33759952

RESUMEN

Various studies have identified that between 2012 and 2017, Brazil's semiarid region suffered severe drought. However, few studies have analyzed whether this drought also affected the eastern coastal region of Northeast Brazil (ENEB). Therefore, the objective of this work is to identify rainfall anomalies in these regions and verify the hydrometeorological impact on reservoirs in the 2012-2017 interval. For this purpose, we used precipitation data and atmospheric variables in the period from 1981 to 2017 to investigate the rainy season and associated dynamic patterns, as well as the consequences of these mechanisms on the variation of the water parameters of important reservoirs. The results indicated that rain events in the ENEB during 2012-2017 presented similar climatological behavior, without the characteristic of a drought event as observed in the semiarid region. The meteorological analyses showed that the combination of convergence with moisture over the Atlantic Ocean possibly favored greater frequency of shallow convective rainfall in ENEB, an important factor to explain the absence of generalized negative anomalies in the region. As a consequence, the reservoirs did not suffer from water collapse, unlike in the semiarid region.


Asunto(s)
Sequías , Lluvia , Océano Atlántico , Brasil , Estaciones del Año
17.
Braz J Biol ; 82: e236499, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33729383

RESUMEN

Distribution pattern and relative abundance of the agricultural rodent pests of rain-fed and irrigated areas of district Swat Khyber Pakhtunkhwa, Pakistan were recorded from April 2011 to November 2013 using wire mesh live traps. A total of 350 rodents (269 Rattus rattus and 81 Mus musculus) were captured under 2268 trap nights (trap success: 0.15). Regression of daily captures on cumulative captures revealed an estimate of 350 rodents from all the sampled structures with an average of 21.8 rodents per crop field. House rats (R. rattus; 76.8% of captures) were numerically dominant in almost all types of agricultural fields, and were significantly different from the mice (Mus musculus; 23.1% of captures). Both species were found together in some fields. The sex ratio revealed that males outnumbered the females in both of the reported species.


Asunto(s)
Lluvia , Roedores , Agricultura , Animales , Femenino , Masculino , Ratones , Pakistán , Ratas , Simbiosis
18.
J Infect Dev Ctries ; 15(2): 230-236, 2021 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-33690205

RESUMEN

INTRODUCTION: The spatiotemporal patterns of Corona Virus Disease 2019 (COVID-19) is detected in the United States, which shows temperature difference (TD) with cumulative hysteresis effect significantly changes the daily new confirmed cases after eliminating the interference of population density. METHODOLOGY: The nonlinear feature of updated cases is captured through Generalized Additive Mixed Model (GAMM) with threshold points; Exposure-response curve suggests that daily confirmed cases is changed at the different stages of TD according to the threshold points of piecewise function, which traces out the rule of updated cases under different meteorological condition. RESULTS: Our results show that the confirmed cases decreased by 0.390% (95% CI: -0.478 ~ -0.302) for increasing each one degree of TD if TD is less than 11.5°C; It will increase by 0.302% (95% CI: 0.215 ~ 0.388) for every 1°C increase in the TD (lag0-4) at the interval [11.5, 16]; Meanwhile the number of newly confirmed COVID-19 cases will increase by 0.321% (95% CI: 0.142 ~ 0.499) for every 1°C increase in the TD (lag0-4) when the TD (lag0-4) is over 16°C, and the most fluctuation occurred on Sunday. The results of the sensitivity analysis confirmed our model robust. CONCLUSIONS: In US, this interval effect of TD reminds us that it is urgent to control the spread and infection of COVID-19 when TD becomes greater in autumn and the ongoing winter.


Asunto(s)
/epidemiología , Dinámicas no Lineales , Presión Atmosférica , Humanos , Humedad , Conceptos Meteorológicos , Densidad de Población , Lluvia , Análisis Espacio-Temporal , Temperatura , Estados Unidos/epidemiología , Viento
19.
An Acad Bras Cienc ; 93(1): e20200392, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33787756

RESUMEN

Itapuã State Park is located in the municipality of Viamão, between the 30º 20 'and 30º 27' S and between 50º 50' and 51º 05' W, in the state of Rio Grande do Sul, southern Brazil. The Park is one of the state conservation units, maintaining remnants of the Atlantic forest, rocky fields vegetation, coastal forest, "vassoural," mixed grassland, moist, bathed and juncal plains. Artificial pollen traps were installed inside the park, between forest and human-modified field. The study presents a morphological description of 34 plant families, represented by 47 different pollen grains and monilophyte spores (including exotic taxa), unpublished data for the park's palinoflora. Quantitative data revealed the presence of 77% of non-arboreal pollen grains, 20% of arboreal pollen grains, 2% of monilophyte spores and 1% of other that can be both arboreal and non-arboreal pollen grains. Non-arboreal pollen grains, especially Poaceae, dominated in all the traps, even those located in forest areas. The dominance of the human-modified fields around collectors and winds from the northeast influenced the dispersion of these grains. Exotic pollen grains of the Betulaceae family, of Andean origin, also occurred in the pollen rain, resulting from dispersion by atmospheric currents of long distances.


Asunto(s)
Bosques , Polen , Brasil , Humanos , Plantas , Lluvia
20.
J Environ Manage ; 286: 112223, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33684801

RESUMEN

Increases in world population and climate change are some of the pressures affecting water resources for current and future water availability. The variability in water availability can reduce agricultural yields, food supplies and potentially leads to malnutrition and spread of diseases in water-poor countries. Even some water-rich countries can experience prolonged periods of dry weather, causing a drop in water reservoirs levels, forcing more restricted water resources management. Rainwater harvesting is one key option in adapting to water shortage and future demands that may alleviate the pressure on existing water resources. This work evaluates a roof top rainwater harvesting system (RWHS) installed as part of a decentralised wastewater treatment system designed to enable a circular economy by providing a more reliable water supply system in a remote public school in rural India. The effectiveness of the RWHS in reducing the pressure on a groundwater supply was assessed along with the physical, chemical and microbial characteristics of the stored rainwater over time. Further, the application of a low-cost primary treatment to make the harvested water safe to use for multiple purposes was investigated. The results revealed that the harvested water was of acceptable quality at the start of collection, however, microbial abundance increased when the rainwater was stored for a long time without treatment. Thus, a chlorine dosing regimen for the RWHS was designed based on laboratory and field experiments. The results also demonstrated that the low-cost chlorination process was effective in the field in reducing microbial abundance in the stored water for more than 30 days. However, as the residual chlorine level was reduced with time to <0.2 mg/l in the storage vessel, the microbial abundance increased, albeit to a much lower level that meets the Indian bathing water standards. The results provide evidence that installed RWHS has reduced the pressure on existing water supply at the school by up to 25% of the water that used for washing and flushing with no treatment, and with regular chlorination, greater savings and multiple uses of the stored rainwater can be achieved.


Asunto(s)
Purificación del Agua , Recursos Hídricos , India , Lluvia , Agua , Abastecimiento de Agua
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