scholarly journals Identification of Groundwater Contamination in a Rapidly Urbanized Area on a Regional Scale: A New Approach of Multi-Hydrochemical Evidences

2021 ◽  
Vol 18 (22) ◽  
pp. 12143
Author(s):  
Pan Bi ◽  
Lixin Pei ◽  
Guanxing Huang ◽  
Dongya Han ◽  
Jiangmin Song
Keyword(s):  
Groundwater Contamination ◽  
Organic Contaminants ◽  
Urban Areas ◽  
Large Scale ◽  
Regional Scale ◽  
Principal Component ◽  
Livestock Waste ◽  
New Approach ◽  
The Pearl River ◽  
Socioeconomic Data

Efficient identification of groundwater contamination is a major issue in the context of groundwater use and protection. This study used a new approach of multi-hydrochemical indicators, including the Cl-Br mass ratio, the hydrochemical facies, and the concentrations of nitrate, phosphate, organic contaminants, and Pb in groundwater to identify groundwater contamination in the Pearl River Delta (PRD) where there is large scale urbanization. In addition, the main factors resulting in groundwater contamination in the PRD were also discussed by using socioeconomic data and principal component analysis. Approximately 60% of groundwater sites in the PRD were identified to be contaminated according to the above six indicators. Contaminated groundwaters commonly occur in porous and fissured aquifers but rarely in karst aquifers. Groundwater contamination in porous aquifers is positively correlated with the urbanization level. Similarly, in fissured aquifers, the proportions of contaminated groundwater in urbanized and peri-urban areas were approximately two times that in non-urbanized areas. Groundwater contamination in the PRD was mainly attributed to the infiltration of wastewater from township-village enterprises on a regional scale. In addition, livestock waste was also an important source of groundwater contamination in the PRD. Therefore, in the future, the supervision of the wastewater discharge of township-village enterprises and the waste discharge of livestock should be strengthened to protect against groundwater contamination in the PRD.

scholarly journals Mid-21st century air quality at the urban scale under the influence of changed climate and emissions: case studies for Paris and Stockholm

2015 ◽  
Vol 15 (19) ◽  
pp. 27041-27085
Author(s):  
K. Markakis ◽  
M. Valari ◽  
M. Engardt ◽  
G. Lacressonnière ◽  
R. Vautard ◽  
...  
Keyword(s):  
Climate Change ◽  
Urban Areas ◽  
Large Scale ◽  
Regional Scale ◽  
Influential Factor ◽  
Daily Average ◽  
Pollutant Concentrations ◽  
Emission Projections ◽  
The Impact ◽  
The City

Abstract. Ozone, PM10 and PM2.5 concentrations over Paris, France and Stockholm, Sweden were modeled at 4 and 1 \\unit{km} horizontal resolutions respectively for the present and 2050 periods employing decade-long simulations. We account for large-scale global climate change (RCP-4.5) and fine resolution bottom-up emission projections developed by local experts and quantify their impact on future pollutant concentrations. Moreover, we identify biases related to the implementation of regional scale emission projections over the study areas by comparing modeled pollutant concentrations between the fine and coarse scale simulations. We show that over urban areas with major regional contribution (e.g., the city of Stockholm) the bias due to coarse emission inventory may be significant and lead to policy misclassification. Our results stress the need to better understand the mechanism of bias propagation across the modeling scales in order to design more successful local-scale strategies. We find that the impact of climate change is spatially homogeneous in both regions, implying strong regional influence. The climate benefit for ozone (daily average and maximum) is up to −5 % for Paris and −2 % for Stockholm city. The joined climate benefit on PM2.5 and PM10 in Paris is between −10 and −5 % while for Stockholm we observe mixed trends up to 3 % depending on season and size class. In Stockholm, emission mitigation leads to concentration reductions up to 15 % for daily average and maximum ozone and 20 % for PM and through a sensitivity analysis we show that this response is entirely due to changes in emissions at the regional scale. On the contrary, over the city of Paris (VOC-limited photochemical regime), local mitigation of NOx emissions increases future ozone concentrations due to ozone titration inhibition. This competing trend between the respective roles of emission and climate change, results in an increase in 2050 daily average ozone by 2.5 % in Paris. Climate and not emission change appears to be the most influential factor for maximum ozone concentration over the city of Paris, which may be particularly interesting in a health impact perspective.

scholarly journals The national and regional impacts of direct payments modulation in the Czech Republic

2009 ◽  
Vol 55 (No. 4) ◽  
pp. 200-210
Author(s):  
T. Medonos ◽  
L. Jelínek ◽  
J. Humpál
Keyword(s):  
Czech Republic ◽  
Urban Areas ◽  
Large Scale ◽  
Agricultural Sector ◽  
Regional Scale ◽  
Farm Size ◽  
The Czech Republic ◽  
Regional Impacts ◽  
Direct Payments ◽  
Farm Structures

This paper addresses <i>(ex ante)</i> the issue of the potential impact of the modulation of direct payments on a sector and regional scale in the Czech Republic. The ultimate version of the compulsory modulation measure adopted under the Health Check of the Common Agricultural Policy (CAP) assumes the reduction of direct payments if the total individual claim exceeds 5 thousand € or 300 thousand € level. The Czech agricultural sector will be impacted by this measure substantially, given the large scale farming enterprises. In 2013, the total farmers’ direct payments will be cut by more than 10% (€ 91 million). Moreover, there are regional differences in farm structures (the average farm size and the extent of collectivization) which will bring about various effects of policies in the heterogeneous regions. The analysis further shows that the regions that are least affected are at the same time more environmental sensitive and are mostly situated in the mountainous or sub-mountainous parts of the country or more urban areas than the average. Hence the effect of the modulation, from a purely environmental perspective, may not contradict the objectives of other environmental policies. That is to say the regions that need support the most will be reduced the least. However, the picture is less obvious in the regional economies where more rural regions (potentially more vulnerable with socio-economic problems) tend to be more affected.

scholarly journals Validation of the Swiss methane emission inventory by atmospheric observations and inverse modelling

2016 ◽  
Vol 16 (6) ◽  
pp. 3683-3710 ◽  
Author(s):  
Stephan Henne ◽  
Dominik Brunner ◽  
Brian Oney ◽  
Markus Leuenberger ◽  
Werner Eugster ◽  
...  
Keyword(s):  
Natural Gas ◽  
Greenhouse Gas ◽  
Urban Areas ◽  
Large Scale ◽  
Transport Model ◽  
Regional Scale ◽  
Inverse Modelling ◽  
Gas Distribution ◽  
Bottom Up ◽  
Ch4 Emissions

Abstract. Atmospheric inverse modelling has the potential to provide observation-based estimates of greenhouse gas emissions at the country scale, thereby allowing for an independent validation of national emission inventories. Here, we present a regional-scale inverse modelling study to quantify the emissions of methane (CH4) from Switzerland, making use of the newly established CarboCount-CH measurement network and a high-resolution Lagrangian transport model. In our reference inversion, prior emissions were taken from the "bottom-up" Swiss Greenhouse Gas Inventory (SGHGI) as published by the Swiss Federal Office for the Environment in 2014 for the year 2012. Overall we estimate national CH4 emissions to be 196 ± 18 Gg yr−1 for the year 2013 (1σ uncertainty). This result is in close agreement with the recently revised SGHGI estimate of 206 ± 33 Gg yr−1 as reported in 2015 for the year 2012. Results from sensitivity inversions using alternative prior emissions, uncertainty covariance settings, large-scale background mole fractions, two different inverse algorithms (Bayesian and extended Kalman filter), and two different transport models confirm the robustness and independent character of our estimate. According to the latest SGHGI estimate the main CH4 source categories in Switzerland are agriculture (78 %), waste handling (15 %) and natural gas distribution and combustion (6 %). The spatial distribution and seasonal variability of our posterior emissions suggest an overestimation of agricultural CH4 emissions by 10 to 20 % in the most recent SGHGI, which is likely due to an overestimation of emissions from manure handling. Urban areas do not appear as emission hotspots in our posterior results, suggesting that leakages from natural gas distribution are only a minor source of CH4 in Switzerland. This is consistent with rather low emissions of 8.4 Gg yr−1 reported by the SGHGI but inconsistent with the much higher value of 32 Gg yr−1 implied by the EDGARv4.2 inventory for this sector. Increased CH4 emissions (up to 30 % compared to the prior) were deduced for the north-eastern parts of Switzerland. This feature was common to most sensitivity inversions, which is a strong indicator that it is a real feature and not an artefact of the transport model and the inversion system. However, it was not possible to assign an unambiguous source process to the region. The observations of the CarboCount-CH network provided invaluable and independent information for the validation of the national bottom-up inventory. Similar systems need to be sustained to provide independent monitoring of future climate agreements.

scholarly journals Detecting Traffic Anomalies in Urban Areas Using Taxi GPS Data

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Weiming Kuang ◽  
Shi An ◽  
Huifu Jiang
Keyword(s):  
Traffic Flow ◽  
Urban Areas ◽  
Large Scale ◽  
Detection Method ◽  
Principal Component ◽  
Transportation Systems ◽  
Gps Data ◽  
Metropolitan Cities ◽  
Gps Devices ◽  
Traffic Anomaly

Large-scale GPS data contain hidden information and provide us with the opportunity to discover knowledge that may be useful for transportation systems using advanced data mining techniques. In major metropolitan cities, many taxicabs are equipped with GPS devices. Because taxies operate continuously for nearly 24 hours per day, they can be used as reliable sensors for the perceived traffic state. In this paper, the entire city was divided into subregions by roads, and taxi GPS data were transformed into traffic flow data to build a traffic flow matrix. In addition, a highly efficient anomaly detection method was proposed based on wavelet transform and PCA (principal component analysis) for detecting anomalous traffic events in urban regions. The traffic anomaly is considered to occur in a subregion when the values of the corresponding indicators deviate significantly from the expected values. This method was evaluated using a GPS dataset that was generated by more than 15,000 taxies over a period of half a year in Harbin, China. The results show that this detection method is effective and efficient.

scholarly journals Regional-Scale Rainy Season Onset Detection: A New Approach Based on Multivariate Analysis

2013 ◽  
Vol 26 (22) ◽  
pp. 8916-8928 ◽  
Author(s):  
Joseph Boyard-Micheau ◽  
Pierre Camberlin ◽  
Nathalie Philippon ◽  
Vincent Moron
Keyword(s):  
Rainy Season ◽  
Regional Scale ◽  
Principal Component ◽  
Local Scale ◽  
Climatic Conditions ◽  
Rainfall Thresholds ◽  
New Approach ◽  
Dry Spell ◽  
Definition Of ◽  
Crucial Parameter

Abstract In agroclimatology, the rainy season onset and cessation dates are often defined from a combination of several empirical rainfall thresholds. For example, the onset may be the first wet day of N consecutive days receiving at least P millimeters without a dry spell lasting n days and receiving less than p millimeters in the following C days. These thresholds are parameterized empirically in order to fit the requirements of a given crop and to account for local-scale climatic conditions. Such local-scale agroclimatic definition is rigid because each threshold may not be necessarily transposable to other crops and other climate environments. A new approach is developed to define onset/cessation dates and monitor their interannual variability at the regional scale. This new approach is less sensitive to parameterization and local-scale contingencies but still has some significance at the local scale. The approach considers multiple combinations of rainfall thresholds in a principal component analysis so that a robust signal across space and parameters is extracted. The regional-scale onset/cessation date is unequally influenced by input rainfall parameters used for the definition of the local rainy season onset. It appears that P is a crucial parameter to define onset, C plays a significant role at most stations, and N seems to be of marginal influence.

scholarly journals Mid-21st century air quality at the urban scale under the influence of changed climate and emissions – case studies for Paris and Stockholm

2016 ◽  
Vol 16 (4) ◽  
pp. 1877-1894 ◽  
Author(s):  
Konstantinos Markakis ◽  
Myrto Valari ◽  
Magnuz Engardt ◽  
Gwendoline Lacressonniere ◽  
Robert Vautard ◽  
...  
Keyword(s):  
Climate Change ◽  
Urban Areas ◽  
Large Scale ◽  
Regional Scale ◽  
Influential Factor ◽  
Coarse Scale ◽  
Pollutant Concentrations ◽  
Emission Projections ◽  
The Impact ◽  
The City

Abstract. Ozone, PM10 and PM2.5 concentrations over Paris, France and Stockholm, Sweden were modelled at 4 and 1 km horizontal resolutions respectively for the present and 2050 periods employing decade-long simulations. We account for large-scale global climate change (RCP-4.5) and fine-resolution bottom-up emission projections developed by local experts and quantify their impact on future pollutant concentrations. Moreover, we identify biases related to the implementation of regional-scale emission projections by comparing modelled pollutant concentrations between the fine- and coarse-scale simulations over the study areas. We show that over urban areas with major regional contribution (e.g. the city of Stockholm) the bias related to coarse-scale projections may be significant and lead to policy misclassification. Our results stress the need to better understand the mechanism of bias propagation across the modelling scales in order to design more successful local-scale strategies. We find that the impact of climate change is spatially homogeneous in both regions, implying strong regional influence. The climate benefit for ozone (daily mean and maximum) is up to −5 % for Paris and −2 % for Stockholm city. The climate benefit on PM2.5 and PM10 in Paris is between −5 and −10 %, while for Stockholm we estimate mixed trends of up to 3 % depending on season and size class. In Stockholm, emission mitigation leads to concentration reductions up to 15 % for daily mean and maximum ozone and 20 % for PM. Through a sensitivity analysis we show that this response is entirely due to changes in emissions at the regional scale. On the contrary, over the city of Paris (VOC-limited photochemical regime), local mitigation of NOx emissions increases future ozone concentrations due to ozone titration inhibition. This competing trend between the respective roles of emission and climate change, results in an increase in 2050 daily mean ozone by 2.5 % in Paris. Climate and not emission change appears to be the most influential factor for maximum ozone concentration over the city of Paris, which may be particularly interesting from a health impact perspective.

scholarly journals Regional differences in resilience of social and physical systems: Case study of Puerto Rico after Hurricane Maria

2020 ◽  
pp. 239980832098074
Author(s):  
Takahiro Yabe ◽  
P Suresh C Rao ◽  
Satish V Ukkusuri
Keyword(s):  
Puerto Rico ◽  
Urban Communities ◽  
Urban Areas ◽  
Large Scale ◽  
Regional Scale ◽  
Quality Data ◽  
Economic Systems ◽  
Median Income ◽  
Physical Systems ◽  
Physical Infrastructure

Physical infrastructure networks in diverse urban settlements are designed to be robust and reliable, while the socio-economic systems offer the necessary adaptive capacity at household, city, and regional scales to recover from major service disruptions resulting from disasters. Here, our urban resilience analyses are based on exploring explicit links between the physical infrastructure/assets and the socio-economic systems. Increased availability of high-quality data from mobile devices allows quantification of diverse socio-economic metrics and thus enables tracking city- and regional-scale community recovery from disasters. Here, recovery trajectories for five regions within Puerto Rico island with differences in socio-economic status (e.g., median income) after Hurricanes Irma and Maria are analyzed using large-scale mobility data and are combined with earlier synthesis of seven global cities based on capital portfolio analysis. Systemic inequalities are manifested in highly variable ability to cope with chronic shocks and recovery from extreme events. Island urban communities face the geographic-isolation effect, legacy socioeconomic constraints, and chronic inefficiencies in governance, all of which delay recovery from disasters. Hurricane recovery efforts include two types of responses. First, in larger urban areas, households use their social ties and financial resources to evacuate to larger cities and return when damaged facilities and infrastructure are repaired. Second, smaller urban communities are already adapted to coping with inadequate critical services and experience disproportionate impacts of disasters. Lacking socio-economic resources, such communities self-organize to access local and external resources and actively engage in repairing and rebuilding damaged facilities. However, recovery is much slower than their counterparts in larger cities. Given the interdependencies of connected social and physical systems and cross-scale feedbacks, such inequalities must be addressed at both city and regional scales to continue progress in urban community preparedness for and recovery from disasters.

scholarly journals Urbanization effect on trends in sunshine duration in China

2017 ◽  
Vol 35 (4) ◽  
pp. 839-851 ◽  
Author(s):  
Yawen Wang ◽  
Martin Wild ◽  
Arturo Sanchez-Lorenzo ◽  
Veronica Manara
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Large Scale ◽  
Sunshine Duration ◽  
Regional Scale ◽  
Urbanization Effect ◽  
Surface Solar Radiation ◽  
Urbanization Level ◽  
Decadal Variations

Abstract. There is an ongoing debate on whether the observed decadal variations in surface solar radiation, known as dimming and brightening periods, are a large-scale or solely local phenomenon. We investigated this issue using long-term sunshine duration records from China, which experienced a rapid increase in urbanization during the past decades. Over the period 1960–2013, 172 pairs of urban and nearby rural stations were analyzed. Urban and rural sunshine duration trends show similar spatial patterns during a dimming phase (1960–1989) and a subsequent period during which trends were leveling off (1990–2013). This indicates that rather than local effects, the trends in sunshine duration are on more of a national or regional scale in China. Nevertheless, in the dimming phase, the declining rate of sunshine duration in rural areas is around two-thirds of that in urban areas. The ratio of rural to urban dimming generally increases from a minimum of 0.39 to a maximum of 0.87 with increasing indices of urbanization calculated based on the year 2013. It reaches a maximum when the urbanization level exceeds 50 %, the urban population exceeds 20 million, or the population density becomes higher than 250 person km−2. After the transition into the leveling-off period, sunshine duration trends are no longer significantly affected by urbanization. Meanwhile, the number of laws and regulations related to air pollution and investment in pollution treatment have been increasing in China.

Scientific-methodological approach to the substantiation of the rational seasonal scenario of using combine harvesters by large-scale agricultural producers

2020 ◽  
pp. 205-217
Author(s):  
V. Skibchyk ◽  
V. Dnes ◽  
R. Kudrynetskyi ◽  
O. Krypuch
Keyword(s):  
Large Scale ◽  
System Analysis ◽  
Methodological Approach ◽  
Production Unit ◽  
Agricultural Producers ◽  
New Approach ◽  
Rational Use ◽  
Road Map ◽  
Analysis And Synthesis ◽  
Combine Harvesters

Аnnotation Purpose. To increase the efficiency of technological processes of grain harvesting by large-scale agricultural producers due to the rational use of combine harvesters available on the farm. Methods. In the course of the research the methods of system analysis and synthesis, induction and deduction, system-factor and system-event approaches, graphic method were used. Results. Characteristic events that occur during the harvesting of grain crops, both within a single production unit and the entire agricultural producer are identified. A method for predicting time intervals of use and downtime of combine harvesters of production units has been developed. The roadmap of substantiation the rational seasonal scenario of the use of grain harvesters of large-scale agricultural producers is developed, which allows estimating the efficiency of each of the scenarios of multivariate placement of grain harvesters on fields taking into account influence of natural production and agrometeorological factors on the efficiency of technological cultures. Conclusions 1. Known scientific and methodological approaches to optimization of machine used in agriculture do not take into account the risks of losses of crops due to late harvesting, as well as seasonal natural and agrometeorological conditions of each production unit of the farmer, which requires a new approach to the rational use of rational seasonal combines of large agricultural producers. 2. The developed new approach to the substantiation of the rational seasonal scenario of the use of combined harvesters of large-scale agricultural producers allows taking into account the costs of harvesting of grain and the cost of the lost crop because of the lateness of harvesting at optimum variants of attraction of additional free combine harvesters. provides more profit. 3. The practical application of the developed road map will allow large-scale agricultural producers to use combine harvesters more efficiently and reduce harvesting costs. Keywords: combine harvesters, use, production divisions, risk, seasonal scenario, large-scale agricultural producers.

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