People or systems? To blame is human. The fix is to engineer

Person-centered safety theories that place the burden of causality on human traits and actions have been largely dismissed in favor of systems-centered theories. Students and practitioners are now taught that accidents are caused by multiple factors and occur due to the complex interactions of numerous work system elements, human and non-human. Nevertheless, person-centered approaches to safety management still prevail. This paper explores the notion that attributing causality and blame to people persists because it is both a fundamental psychological tendency as well as an industry norm that remains strong in aviation, health care, and other industries. Consequences of that possibility are discussed and a case is made for continuing to invest in whole-system design and engineering solutions.     

Soil Fertility in Relation to Slope Position and Agricultural Land Use: A Case Study of Umbulo Catchment in Southern Ethiopia

A study was conducted in southern Ethiopia to evaluate the nutrient status on smallholder farms with respect to land use class (garden, grassland, and outfield) and slope position (upper, middle, and lower). Soil physical and chemical properties were quantified using soil samples collected at two depths (0–15 and 15–30 cm). Available phosphorous was significantly different among the three land use classes. However, organic carbon and total nitrogen were lower in the outfield compared to the garden and grass land but not significantly different. The lower than expected nutrient status of the garden and grassland, which receive almost all available organic supplements, was attributed to the overall low availability of these inputs. Similarly, pH and cation exchange capacity were not significantly different among the different land use classes. However, the sum of the exchangeable cations was significantly higher in the garden compared to the outfields. Comparison at landscape level revealed that the sand fraction was significantly greater, whereas the silt fractions were significantly smaller, on the lower slopes relative to the middle slopes. Moreover, the organic carbon, total nitrogen, cation exchange capacity, Ca, and Mg values were significantly less on lower slopes than upper and middle slopes. Perhaps this is because of leaching and the effect of deposition of coarser sediments from the prevailing gully system. Overall, the fertility of the soil was adequate for supporting smallholder farming, but consideration must be given to reducing pressure on the land resources, addressing erosion problems, and providing a line of credit for purchasing inputs.     

Octachlorodibenzo-p-dioxin in wood treatment materials and treated wood

The octachlorodibenzo-p-dioxin (OCDD) concentrations have been determined in aged samples of commercial pentachlorophenol (PCP), in wood protection formulations containing PCP and in wood treated with PCP as a preservative or as an anti-sapstain treatment. The concentrations of OCDD found in the various samples are within the range expected from the amount of commercial PCP initially present in the samples. In view of the known stability of OCDD the results are interpreted as indicating that the formulation, treatment and ageing processes have not led to any substantial conversion of PCP to OCDD; although one result indicates that outdoor exposure of treated samples increased the OCDD concentration by a factor of approximately 2 after $\text{3}\text{1}\text{2}$ years. Analysis of aged samples of treated wood indicate that OCDD is lost much less rapidly from the wood than PCP.     

A method to determine residue levels of persistent organochlorine pesticides in human milk from Indonesian women

A method has been developed for the analysis of organochlorine pesticides in human milk using solvent extraction, Florisil solid phase extraction clean-up and analysis by gas chromatography with an electron capture detector. The recovery of analytes from spiked milk samples was in the range 53 +/- 1% to 109 +/- 7% (n = 9). A small number of samples were obtained from women in a rural and an urban area of Indonesia and analysed using the developed method. The results are reported on a milk fat basis. All samples contained detectable residues of p,p'-DDT (urban mean 0.11 +/- 0.18 mgkg(-1) (n = 5), rural mean 0.07 +/- 0.03 mg kg(-1) (n = 5)) and p,p'-DDE (urban mean 0.05 +/- 0.04 m kg(-1) (n = 5), rural mean 0.76 +/- 1.46 mg kg(-1) (n = 5)). Residues of HCB, betaHCH, alpha-endosulfan and dieldrin were also detected in some samples. There was no significant difference (at the 95% confidence level) in levels of pesticides between urban and rural areas. The levels of organochlorine pesticides in milk from Indonesian women were lower than those reported from Indonesian women exposed to DDT through malaria eradication schemes and were similar to levels reported from UK and Japan.     

Are soil conservation technologies “win‐win?” A case study of Anjeni in the north‐western Ethiopian highlands

This study measures the impact of fanya juu terraces on the net value of crop income in a high‐rainfall area in the Ethiopian highlands using cross‐sectional multiple plot observations. Using propensity score matching methods we find that the net value of crop income for plots with fanya juu terraces is lower than for plots without fanya juu terraces. This finding makes it difficult to avoid concluding that while the technologies might reduce soil erosion and associated off‐site effects, they do so at the expense of poor farmers in the Ethiopian highlands. Therefore, fanya juu terraces cannot be characterized as a “win‐win” measure to reduce soil erosion. New agricultural technologies need to be profitable to the farmer if they are to be adopted and sustained.     

Geochemical interactions between process-affected water from oil sands tailings ponds and North Alberta surficial sediments

In Northern Alberta, the placement of out-of-pit oil sands tailings ponds atop natural buried sand channels is becoming increasingly common. Preliminary modeling of such a site suggests that process-affected (PA) pond water will infiltrate through the underlying clay till aquitard, reaching the sand channel. However, the impact of seepage upon native sediments and groundwater resources is not known. The goal of this study is to investigate the role of adsorption and ion exchange reactions in the clay till and their effect on the attenuation or release of inorganic species. This was evaluated using batch sorption experiments (traditional and a recent modification using less disturbed sediment samples) and geochemical modeling with PHREEQC. The results show that clay till sediments have the capacity to mitigate the high concentrations of ingressing sodium (600 mg L(-1)), with linear sorption partitioning coefficients (K(d)) of 0.45 L kg(-1). Ion exchange theory was required to account for all other cation behaviour, precluding the calculation of such coefficients for other species. Qualitative evidence suggests that chloride will behave conservatively, with high concentrations remaining in solution (375 mg L(-1)). As a whole, system behaviour was found to be controlled by a combination of competitive ion exchange, dissolution and precipitation reactions. Observations, supported by PHREEQC simulations, suggest that the influx of PA water will induce the dissolution of pre-existing sulphate salts. Sodium present in the process-affected water will exchange with sediment-bound calcium and magnesium, increasing the divalent ions' pore fluid concentrations, and leading to the precipitation of a calcium-magnesium carbonate mineral phase. Thus, in similar tailings pond settings, particularly if the glacial till coverage is thin or altogether absent, it is reasonable to expect that high concentrations of sodium and chloride will remain in solution, while sulphate concentrations will exceed those of the ingressing plume (150 mg L(-1)).     

Phosphorus fluxes at the sediment–water interface in subtropical wetlands subjected to experimental warming: A microcosm study

Global warming is increasingly challenging for wetland ecological function. A temperature controlled microcosm system was developed to simulate climate change scenarios of an ambient temperature (control) and an elevated temperature (+5 °C). The effects and associated mechanisms of warming on phosphorus (P) fluxes at the sediment–water interface of six subtropical wetlands were investigated. The results indicated that P fluxes were generally enhanced under the experimental warming as measured by higher P concentrations in the porewater and overlying water as well as higher benthic P fluxes. The release of P from sediment to porewater occurred more strongly and quickly in response to experimental warming compared to the subsequent upward transfer into overlying water. The average accumulative benthic P output from the tested wetlands under the experimental warming was greater by 12.9 μg cm^?2 y^?1 (28%) for total P and 8.26 μg cm^?2 y^?1 (25%) for dissolved reactive P, compared to the ambient scenarios. Under warming the redistribution of P fractions in sediments occurred with greater NH₄Cl–P and lower BD–P (extracted by a bicarbonate buffered dithionite solution) accompanied by greater NaOH–P. The higher temperature enhanced total phospholipid fatty acids. A shift in the microbial community was also observed with a relative dominance of fungi (a 4.7% increase) and a relative decline (by 18%) in bacterial abundance, leading to the higher secretion of phosphatase. Comparing between wetlands, the potential P fluxes in the nutrient-enriched wetlands were less impacted by warming than the other wetland types investigated. Thus wetlands characterized by low or medium concentrations of P in sediments were more susceptible to warming compared to P-rich wetlands.     

Reach and messages of the world's largest ivory burn

Recent increases in ivory poaching have depressed African elephant populations. Successful enforcement has led to ivory stockpiling. Stockpile destruction is becoming increasingly popular, and most destruction has occurred in the last 5 years. Ivory destruction is intended to send a strong message against ivory consumption, both in promoting a taboo on ivory use and catalyzing policy change. However, there has been no effort to establish the distribution and extent of media reporting on ivory destruction events globally. We analyzed media coverage of the largest ivory destruction event in history (Kenya, 30 April 2016) across 11 nation states connected to ivory trade. We used an online‐media crawling tool to search online media outlets and subjected 5 of the largest print newspapers (by circulation) in 5 nations of interest to content analysis. Most online news on the ivory burn came from the United States (81% of 1944 articles), whereas most of the print news articles came from Kenya (61% of 157 articles). Eighty‐six to 97% of all online articles reported the burn as a positive conservation action, whereas 4–50% discussed ivory burning as having a negative impact on elephant conservation. Most articles discussed law enforcement and trade bans as effective for elephant conservation. There was more relative search interest globally in the 2016 Kenyan ivory burn than any other burn in 5 years. Ours is the first attempt to track the reach of media coverage relative to an ivory burn and provides a case study in tracking the effects of a conservation‐marketing event.