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[en] Legal and policy initiatives to address the environmental dimensions of armed conflicts and their impact on people, ecosystems and sustainable development are highly dependent on the availability of environmental data from conflict-affected areas. Socio-political and security conditions in these areas often impede data collection, while traditional models of post-conflict environmental assessments are limited in scope. In response, an increasing range of actors is utilising remote sensing and open source data collection to identify and estimate health and ecological risks during and after conflicts. This paper considers the role of participatory citizen science methodologies in complementing both remote monitoring and post-conflict assessments. It examines existing models and mechanisms for environmental data collection and utilisation in conflict contexts, and the extent to which the core values and principles of citizen science are transferable. We find that ‘civilian science’ is feasible and could be well-suited to conflict conditions. In addition to addressing gaps in data collection, it may also empower communities affected by environmental degradation, enhance their environmental human rights, supplement the often limited monitoring capacity of governmental agencies and facilitate cooperation and peacebuilding. The paper concludes by proposing methodological approaches for three common forms of environmental degradation associated with armed conflicts.
[en] In this paper, 329 Landsat images combined with the Deeply Clear Water Extraction Index were applied to delineate boundaries of Hongjiannao Lake during 1986–2018. The net shoreline movement (NSM) and linear regression rate (LRR) achieved by Digital Shoreline Analysis System (DSAS) were employed to depict the distance and rate change of lake shorelines. Based on the waterline method and lake boundaries, the water levels were derived from ASTER GDEM V2. Water volume variations were evaluated using the combination of lake area and water level. The variations in Hongjiannao Lake can be grouped into three stages: (i) The lake area, water level, and volume variations slightly declined from 57.25 km2, 1211.15 m, and − 0.0220 km3 in 1986 to 56.36 km2, 1210.66 m, and − 0.036 km3 in 1997, respectively. The average degradation distance (NSM) and rate (LRR) of lake shorelines were 74.26 m and 3.48 m/a, respectively. Although these three aspects slightly decreased, they maintained a stable high level due to stability of natural factors. (ii) A rapid decrease in these three aspects during 1998–2015 was expressed by rates of − 1.15 km2/a (the total decrease was − 21.72 km2), − 0.18 m/a (the total decrease was − 3.45 m), and − 0.0068 km3/a (the total decrease was − 0.1419 km3), respectively. The average shrinkage distance (NSM) and rate (LRR) of lake boundaries were 1049.35 m and 55.00 m/a, respectively, and gradually intensifying human activities were the leading factor. (iii) These three aspects increased from 31.75 km2, 1207.03 m, and − 0.1852 km3 in 2016 to 36.19 km2, 1207.23 m, and − 0.1883 km3, respectively, in 2018. The average enlargement distance (NSM) and rate (LRR) of lake shorelines were 196.87 m and 67.85 m/a, respectively, mainly caused by closing of small mines, sluicing activities, and increase in annual precipitation.
[en] We analyzed data from 1138 wetland sites across the conterminous United States (US) as part of the 2011 National Wetland Condition Assessment (NWCA) to investigate the response of indicators of wetland quality to indicators of human disturbance at regional and continental scales. The strength and nature of these relationships in wetlands have rarely been examined over large regions, due to the paucity of large-scale datasets. Wetland response indicators were a multimetric index of vegetation condition (VMMI), percent relative cover of alien plant species, soil lead and phosphorus, and water column total nitrogen and total phosphorus. Site-level disturbance indices were generated from field observations of disturbance types within a circular 140-m radius area around the sample point. Summary indices were calculated representing disturbances for ditching, damming, filling/erosion, hardening, vegetation replacement, and vegetation removal. Landscape-level disturbance associated with agricultural and urban land cover, roads, and human population were based on GIS data layers quantified in 200, 500, and 1000-m circular buffers around each sample point. Among these three buffer sizes, the landscape disturbance indicators were highly correlated and had similar relationships with the response indictors. Consequently, only the 1000-m buffer data were used for subsequent analyses. Disturbance-response models built using only landscape- or only site-level disturbance variables generally explained a small portion of the variance in the response variables (R2 < 0.2), whereas models using both types of disturbance data were better at predicting wetland responses. The VMMI was the response variable with the strongest relationship to the disturbances assessed in the NWCA (national model R2 = 0.251). National multiple regression models for the soil and water chemistry and percent alien cover responses to disturbance indices were not significant. The generally low percentage of significant models and the wide variation in predictor variables suggests that stressor-response relationships vary considerably across the diversity of wetland types and landscape settings found across the conterminous US. Logistic regression modeling was more informative, resulting in significant national and regional models predicting site presence/absence of alien species and/or the concentration of lead in wetland soils above background.
[en] The Total Maximum Daily Load (TMDL) for selenium in the freshwater drainages to Newport Bay, California, is being developed based on selenium concentration in the tissues of fish and bird eggs. This paper demonstrates the use of fish mesocosms and monitoring results to facilitate the comparisons of selenium contamination across fish species and areas of the watershed with differing fish assemblages. In this watershed, mosquitofish dominate across all the small, upper watershed drainages while sunfish family species dominate in deeper, ponded reaches of the lower watershed. Mesocosms were used to hold mosquitofish in ponds where they did not occur to compare their concentrations of bioaccumulated selenium to the tissue selenium of resident bluegill sunfish of the same pond. The caged fish were allowed to bioaccumulate selenium over time to achieve tissue concentrations at equilibrium conditions to compare as a ratio to resident bluegill. Those results were compared to the ratio of tissue concentrations from a later sampling of the same pond when the two species were found to co-occur for the first time. The ratios were brought into agreement only after altering assumptions of time to achieve equilibrium in bioaccumulated selenium for the transplanted mosquitofish and extrapolation of the mesocosm results. The technique demonstrates important considerations for the use of mesocosms to facilitate comparisons between allopatric species in terms of selenium bioaccumulation. A careful consideration of trophic level of the caged fish was found to be critical in setting the total time of bioaccumulation as part of the experimental design needed to achieve equilibrium tissue concentrations.
[en] Our aim was to assess local population exposure to heavy metals resulting from soil and vegetable contamination in Tarnaveni, Romania, an area located near a former chemical factory. We collected residential soil and vegetable samples from Tarnaveni and measured chromium (Cr), lead (Pb), and manganese (Mn) levels by atomic absorption spectrometry. We evaluated the relationship between soil and vegetable metals and the distance from the shuttered chemical factory, and calculated the hazard index to assess local population metal exposure via contaminated vegetable ingestion. Soil metal concentrations ranged between 15.6 and 525.8 mg/kg for total Cr, between 25.4 and 559.5 mg/kg for Pb, and between 363.1 and 1389.6 mg/kg for Mn. We found average concentrations of 17.8 mg/kg for total Cr, 2.2 mg/kg for Pb, and 116.6 mg/kg for Mn in local vegetables. We found soil concentrations for all three metals that exceeded normal background levels according to Romanian regulations (Pb exceeded 100 mg/kg in some of the samples), as well as measurable concentrations of metals in all analyzed vegetable samples. These preliminary data underscore a need for a more extensive investigation into associated adverse health effects in the exposed population.
[en] The concept of green manufacturing is emerging as a means of enhancing a firm’s competitiveness through intelligent systems and process improvement to eliminate adverse effects on the environment. However, environmental performance (EPA) is challenging from the decision-making perspective because of difficulty determining and prioritising the proper factors that have significant effect on a firm’s EPA. This study was conducted with the objective of enhancing the effectiveness of the analytic hierarchy process (AHP) to assess EPA by integrating exploratory factor analysis and confirmatory factory analysis to validate suitable criteria and sub-criteria. A questionnaire survey was employed as a tool to collect data from 341 managers of Thailand and Taiwan’s food industry and the AHP approach used for normalisation, ranking, and simulation of sensitivity analysis. The results obtained indicate that quality policy, quality assurance, and quality control, respectively, are the three most important factors in the measurement of EPA, whereas organisational support in innovativeness is assigned the lowest priority. Based on simulations for sensitivity analysis, the results can be applied to guide managers’ decisions in the course of steering their firms towards sustainable manufacturing.
[en] This study investigated the concentration and sources of polycyclic aromatic hydrocarbons (PAHs) in the sediments of Oji River due to point sources of pollution from abattoir and power plant and determined the ecological and human health risks associated with the PAHs in the sediments. Oji River in Nigeria receives contaminants from anthropogenic activities relating to waste tires used in singeing cow meats in abattoir and preparing hides and skin for local consumption. It also receives contaminants from power distribution station where the defunct coal power plant used to be situated. These activities have the potential to release polycyclic aromatic hydrocarbons that could accumulate in the river sediments. The PAHs were measured using gas chromatography-mass spectrometry (GC-MS). This study found that the abattoir is responsible for the occurrence of benzo[b]fluoranthene, benzo[k]fluoranthene and benzo[a]pyrene in the sediments around the abattoir. The occurrence and distribution of PAHs around the area affected by the power station was profound as among all the 16 priority PAHs; only naphthalene benzo[g,h,i]perylene, dibenzo[a,h]anthracene and indeno[1,2,3-cd]pyrene were not detected. The five-member ring PAHs were predominant in this section of the river affected by power station. Ecological risks of the PAHs due to the effects of the power station are significant. The total toxicity equivalence (TEQ) of the PAHs upstream the abattoir is insignificant but significant around the abattoir and within the area impacted by the power station. The values of the hazard index (HI) and risk index (RI) indicate insignificant carcinogenic and non-carcinogenic human health risks in all the locations except the area within the influence of the power station where there are insignificant non-carcinogenic risks but significant carcinogenic risks.
[en] Xenobiotic azo dyes and chromate (Cr(VI)) containing industrial wastewaters cause severe ecological problems. The present bioremediation study aims to treat wastewater containing Cr(VI) ions and mixed azo dyes (reactive red 21 (RR21) and reactive orange 16 (RO16)) by Pseudomonas aeruginosa 23N1. The process optimization of bioremediation is investigated using statistical designed experimental tool of response surface methodology. The ANOVA analysis is performed to evaluate optimal biodecolourization condition. This study shows that the amount of yeast extract has major influence on biodecolourization performance. The decolourization of individual RO16 and RR21 dye in presence of 60 mg/L of Cr(VI) ions is obtained as 88.5 ± 0.8 and 92.3 ± 0.7% for 100 and 150 mg/L initial dye concentrations, respectively. In this study, bacteria exhibit high Cr(VI) removal potential of ~ 99.1% against initial Cr(VI) concentration of 150 mg/L. The negative influence of Cr(VI) ions on biodecolourization is only noticed when initial Cr(VI) concentration in wastewater is found above 150 mg/L. The results reveal that bacteria studied here could be used to biodecolourize dyes even in high saline condition (> 6000 mg/L). The reduction of ~ 80% in American Dye Manufacturers Institute colour index value is achieved for mixed dyes solution containing 50 mg/L of both RR21 and RO16 dyes along with 50 mg/L Cr(VI) ions. Significant changes in the UV-visible and ATR-FTIR spectra are observed in treated water that confirms the biodegradation of dyes. Toxicity study with Vigna radiata reveals the non-toxicity of degraded metabolites and strain 23N1 is recommended as an effective bioremediation agent.
[en] Saturated soil paste extracts indicate soluble ions in soil pore water that are available to vegetation. As such, they are thought to accurately describe the relationship between soil and groundwater salinity. To test this assumption, soil and groundwater samples were collected from 575 monitoring wells in saline regions of the Western Canadian Sedimentary Basin (WCSB). Samples were analyzed for electrical conductivity (EC) and Cl−, Na+, Ca2+, Mg2+, K+, SO42−, and HCO− 3 content. We compared groundwater ionic concentrations to paste extracts derived from matching soils, finding that differences from in situ soil porosity cause saturated pastes to underestimate groundwater salinity. Therefore, we provide pedotransfer functions for accurately calculating groundwater quality from soil data. In addition, we discuss the effects of porosity and soil composition on the saturated paste method, as measured through hydraulic conductivity, saturation percent, and sample lithology. Groundwater salinity may also influence further leaching of salts from soil. As produced water (NaCl brine) spills are common across the sulfate-rich soils of the WCSB, we considered the effects of NaCl on leaching of other ions, finding that influx of Na+ into groundwater is associated with increased sulfate leaching from soil. Therefore, considering the secondary effects of produced water on groundwater quality is essential to spill management.
[en] The physical texture of cities is comprised of built-up spaces, open-green spaces, and transportation arteries. Urbanization is a dynamic that compose of each of the factors above in a fair proportion to human beings and nature. On the other hand, due to the rapid increase in urban population, urbanization has become a concept that poses serious problems for cities in the last decades and this leads a pressure on open-green spaces in urban areas. Open-green spaces have a great importance in improving urban life conditions and balancing the destroyed relations between humans and environment. For this reason, the sustainability of urban open-green spaces cannot be ignored in the planning studies. In this study, the change in the urban texture in Nevsehir (Turkey) was evaluated in a 10-year period (2004–2014) through the integration of remote sensing (RS) and geographical information systems (GIS). Through the use of satellite images with high ground sample distance—QuickBird (60 cm) (2004) and Worlview-2 (50 cm) (2014)—the direction of urban expansion and changes which occurred in urban open-green spaces and urban development areas were examined in detail at the whole city and district scales. Analyses consist of satellite image classification, plant index production, and GIS-based analyses methods. According to the results, it was determined that from 2004 to 2014, the 23.28% decrease in urban open-green spaces was detected in Nevsehir city. It was observed that the city expands towards the north-east, south-west, and west. It was indicated that there is a serious increase in built-up areas especially at the north-east part of the city (107.11%). Thus, a significant decrease has happened in the amount of urban open-green spaces in this area.