Large-scale environmental degradation results in inequitable impacts to already impoverished communities: A case study from the floating villages of Cambodia

Cambodian subsistence communities within the Tonle Sap Great Lake area rely on resource extraction from the lake to meet livelihood needs. These fishing communities—many of which consist of dwellings floating on the lake—face potentially profound livelihood challenges because of climate change and changing hydrology due to dam construction for hydroelectricity within the Mekong Basin. We conducted interviews across five village communities, with local subsistence fisher people in the Tonle Sap in 2015, and used thematic analysis methods to reveal a fishery system that is undergoing rapid ecological decline, with local fishing communities increasingly experiencing reductions in available fish stocks. As a result, over 100 000 people living in these communities are experiencing a direct loss of well-being and livelihood. We discuss these losses and consider their implications for the future viability of Cambodian floating village communities.     

Groundwater treatment and aquatic toxicity reduction at a chemical production site

Contaminated groundwater at a chemical antioxidant and phenolic resin chemical production site was subjected to treatability studies to develop design criteria for surface water discharge. Raw groundwater required pretreatment for total suspended solids (TSS) and color removal prior to treatment by ultraviolet light/hydrogen peroxide (UV/H₂O₂). Because of high capital and operating costs for UV/H₂O₂, biological treatment was evaluated as an alternate. Respirometric analyses showed that completely mixed activated sludge could be applied as a treatment technology to the groundwater. Biotreatment resulted in an approximately 70 percent reduction in soluble chemical oxygen demand (SCOD). Residual SCOD was recalcitrant to further biodegradation. The treated effluent was tested for aquatic toxicity using fathead minnows (Pimephales promelas) and Ceriodaphnia dubia and was found to be toxic. Toxicity reduction of biotreatment effluent was evaluated in bench-scale experiments using activated carbon adsorption, filtration, and UV/H₂O₂. Subsequent toxicity testing showed that filtration alone could reduce the bioeffluent toxicity and that residual SCOD was not the primary source of toxicity.     

Opinions of 12 to 13-year-olds in Austria and Australia on the concern,cause and imminence of climate change

Early adolescence (12–13 years old) is a critical but under-researched demographic for the formation of attitudes related to climate change. We address this important area by exploring adolescent views about climate change. This paper presents opinions collected from surveys of 463 1st-year secondary school students (12–13 years old) in public secondary schools in inner-urban centres in Austria and Australia on whether climate change is (1) something about which to worry, (2) caused by humans and (3) happening now. Eligible respondents in both countries showed similar levels of agreement that climate change was probably or definitely something we should (1) worry about (84.6% Austria, 89.1% Australia), which is significantly higher than either country’s adult population. Eligible respondents agreed that climate change probably or definitely is (2) caused by humans (75.6% Austria, 83.6% Australia) and that climate change is probably or definitely something that is (3) happening now (73.1% Austria, 87.5% Australia). Their response differed from the respective adult populations, but in opposite directions. Our results suggest that socio-cultural worldview may not have as much influence on this age group as it does on the respective adult populations and suggests that this age group would be receptive and ready for climate science education and engagement initiatives.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01356-2) contains supplementary material, which is available to authorized users.     

Pollution magnet: nano-magnetite for arsenic removal from drinking water

Arsenic contamination in groundwater is a severe global problem, most notably in Southeast Asia where millions suffer from acute and chronic arsenic poisoning. Removing arsenic from groundwater in impoverished rural or urban areas without electricity and with no manufacturing infrastructure remains a significant challenge. Magnetite nanocrystals have proven to be useful in arsenic remediation and could feasibly be synthesized by a thermal decomposition method that employs refluxing of FeOOH and oleic acid in 1-octadecene in a laboratory setup. To reduce the initial cost of production, $US 2600/kg, and make this nanomaterial widely available, we suggest that inexpensive and accessible “everyday” chemicals be used. Here we show that it is possible to create functional and high-quality nanocrystals using methods appropriate for manufacturing in diverse and minimal infrastructure, even those without electricity. We suggest that the transfer of this knowledge is best achieved using an open source concept.     

Using the late spring nitrate test to reduce nitrate loss within a watershed

Excessive nitrate leaching from the U.S. Corn Belt has created serious water quality problems and contributed to the expansion of the hypoxic zone in the Gulf of Mexico. We evaluated the effect of implementing the late spring nitrate test (LSNT) for corn (Zea mays L.) grown within a 400-ha, tile-drained subbasin in central Iowa. Surface water discharge and NO3 concentrations from the treated subbasin and two adjacent subbasins receiving primarily fall-applied, anhydrous ammonia were compared. In two of four years, the LSNT method significantly reduced N fertilizer applications compared with the farmers' standard practices. Average corn yield from LSNT fields and nonlimiting N fertilizer check strips was not significantly different. Autoregressive (AR) models using weekly time series in surface water NO3 concentration differences between the LSNT and control subbasins indicated no consistent significant differences during the pre-LSNT (1992-1996) period. However, by the second year (1998) of the treatment period (1997-2000), NO3 concentrations in surface water from the treated subbasin were significantly lower than the concentrations coming from both control basins. Annual average flow-weighted NO3 concentrations for the last two years (1999-2000) were 11.3 mg N L(-1) for the LSNT and subbasin and 16.0 mg N L(-1) for the control subbasins. Based on these values and the AR models, widespread adoption of the LSNT program for managing N fertilizer where fall N application is typically practiced could result in a > or = 30% decrease for NO3 concentrations in surface water.     

Addressing environmental inequalities in UK policy: An action research perspective

In the UK there has been a serious attempt under the current government to foster policy making which is evidence-based and therefore more likely to deliver its intended results. In this article we consider the types of evidence and evidence making that might be required to build effective policy for addressing environmental inequalities. We draw on our experiences of developing an action research approach to policy making in the Environment Agency over a two year period from July 2002 to August 2004. We conclude that an action research approach is well suited to policy making within this new but rapidly growing area of sustainable development policy and urge further exploration of such approaches as a means of better connecting the relevant research, policy making and practitioner communities.     

Updated methods for assessing the impacts of nearby gas drilling and production on neighborhood air quality and human health

An explosive growth in natural gas production within the last decade has fueled concern over the public health impacts of air pollutant emissions from oil and gas sites in the Barnett and Eagle Ford shale regions of Texas. Commonly acknowledged sources of uncertainty are the lack of sustained monitoring of ambient concentrations of pollutants associated with gas mining, poor quantification of their emissions, and inability to correlate health symptoms with specific emission events. These uncertainties are best addressed not by conventional monitoring and modeling technology, but by increasingly available advanced techniques for real-time mobile monitoring, microscale modeling and source attribution, and real-time broadcasting of air quality and human health data over the World Wide Web. The combination of contemporary scientific and social media approaches can be used to develop a strategy to detect and quantify emission events from oil and gas facilities, alert nearby residents of these events, and collect associated human health data, all in real time or near-real time. The various technical elements of this strategy are demonstrated based on the results of past, current, and planned future monitoring studies in the Barnett and Eagle Ford shale regions.

Implications: Resources should not be invested in expanding the conventional air quality monitoring network in the vicinity of oil and gas exploration and production sites. Rather, more contemporary monitoring and data analysis techniques should take the place of older methods to better protect the health of nearby residents and maintain the integrity of the surrounding environment.     

Nitrate loss in subsurface drainage as affected by nitrogen fertilizer rate

The relationships between N fertilizer rate, yield, and NO3 leaching need to be quantified to develop soil and crop management practices that are economically and environmentally sustainable. From 1996 through 1999, we measured yield and NO3 loss from a subsurface drained field in central Iowa at three N fertilizer rates: a low (L) rate of 67 kg ha(-1) in 1996 and 57 kg ha(-1) in 1998, a medium (M) rate of 135 kg ha(-1) in 1996 and 114 kg ha(-1) in 1998, and a high (H) rate of 202 kg ha(-1) in 1996 and 172 kg ha(-1) in 1998. Corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] were grown in rotation with N fertilizer applied in the spring to corn only. For the L treatment, NO3 concentrations in the drainage water exceeded the 10 mg N L(-1) maximum contaminant level (MCL) established by the USEPA for drinking water only during the years that corn was grown. For the M and H treatments, NO3 concentrations exceeded the MCL in all years, regardless of crop grown. For all years, the NO3 mass loss in tile drainage water from the H treatment (48 kg N ha(-1)) was significantly greater than the mass losses from the M (35 kg N ha(-1)) and L (29 kg N ha(-1)) treatments, which were not significantly different. The economically optimum N fertilizer rate for corn was between 67 and 135 kg ha(-1) in 1996 and 114 and 172 kg ha(-1) in 1998, but the net N mass balance indicated that N was being mined from the soil at these N fertilizer levels and that the system would not be sustainable.