Use of Predictive Weather Uncertainties in an Irrigation Scheduling Tool Part II: An Application of Metrics and Adjoints

We apply predictive weather metrics and land model sensitivities to improve the Colorado State University Water Irrigation Scheduler for Efficient Application (WISE). WISE is an irrigation decision aid that integrates environmental and user information for optimizing water use. Rainfall forecasts and verification performance metrics are used to estimate predictive rainfall probabilities that are used as input data within the irrigation decision aid. These input data errors are also used within a land model sensitivity study to diagnose important prognostic water movement behaviors for irrigation tool development purposes simultaneously performing the analysis in space and time. Thus, important questions such as “how long can a crop water application be delayed while maintaining crop yield production?” are addressed by evaluating crop growth stage interactions as a function of soil depth (i.e., space), rainfall events (i.e., time), and their probabilistic uncertainties. Editor’s note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series.     

Arsenic speciation in freshwater snails and its life cycle variation

Terrestrial snails are consumed by humans occasionally and they are an important food source for many creatures including fish and birds. Little is known about arsenic speciation in these gastropods, let alone life cycle variations. Here we report on the arsenic speciation in freshwater snails from Pender Island and Vancouver Island, B.C., Canada, which was determined on methanol/water extracts (43-59% extraction efficiency) by using high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) and HPLC-electrospray tandem mass spectrometry. The tetramethylarsonium ion, oxo-arsenosugars and thio-arsenosugars are the main arsenic species encountered. Arsenobetaine, which is commonly found in the marine environment, is minor. Live bearing snails Viviparidae sp. from Pender Island were maintained in aquaria and the arsenic speciation in the unborn, newly born, and adult animals was monitored. Oxo-arsenosugars predominate in the adults, whereas thio-arsenosugars seem to predominate in juveniles, suggesting that these arsenicals are snail metabolites.     

Organic agriculture and ecosystem services

Ecosystem services (ES), such as biological control, pollination, soil formation, nutrient cycling in agriculture are vital for the sustainable supply of food and fibre. The current trends of decline in the ability of agricultural ecosystems to provide ES pose great threat to food security worldwide. This paper discusses the concept of ES and identifies ES associated with agriculture. It discusses the economic and ecological benefits of these ES on farmland in general and its linkages with organic agriculture. The provision of ES on farmland may help to motivate the redesign of small-scale farms using new eco-technologies based on novel and sound ecological knowledge. This has potential to meet the food demand of growing population without damaging human health and the environment.     

Energy's role in the extraversion (dis)advantage: How energy ties and task conflict help clarify the relationship between extraversion and proactive performance

While academic and practitioner literatures have proposed that extraverts are at an advantage in team‐based work, it remains unclear exactly what that advantage might be, how extraverts attain such an advantage, and under which conditions. Theory highlighting the importance of energy in the coordination of team efforts helps to answer these questions. We propose that extraverted individuals are able to develop more energizing relationships with their teammates and as a result are seen as proactively contributing to their team. However, problems in coordination (i.e., team task conflict) can reverse this extraversion advantage. We studied 27 project‐based teams at their formation, peak performance, and after disbandment. Results suggest that when team task conflict is low, extraverts energize their teammates and are viewed by others as proactively contributing to the team. However, when team task conflict is high, extraverts develop energizing relationships with fewer of their teammates and are not viewed as proactively contributing to the team. Our findings regarding energizing relationships and team task conflict clarify why extraversion is related to proactive performance and in what way, how, and when extraverts may be at a (dis)advantage in team‐based work. Copyright © 2016 John Wiley & Sons, Ltd.     

An integrated approach to the toxicity assessment of Irish marine sediments: validation of established marine bioassays for the monitoring of Irish marine sediments

This paper describes the ecotoxicological evaluation of marine sediments from three sites around Ireland representative of a range of contaminant burdens. A comprehensive assessment of potential sediment toxicity requires the consideration of multiple exposure phases. In addition to the evaluation of multi-exposure phases the use of a battery of multi-trophic test species has been advocated by a number of researchers as testing of single or few organisms may not detect toxicants with a specific mode of action. The Microtox(R) solid phase test (SPT) and the 10-d acute amphipod test with Corophium volutator were used to assess whole sediment toxicity. Porewater and elutriates were assessed with the Microtox(R) acute test, the marine prasinophyte Tetraselmis suecica, and the marine copepod Tisbe battagliai. Solvent extracts were assayed with the Microtox(R) and T. battagliai acute tests. Alexandra Basin was identified as the most toxic site according to all tests, except the Microtox(R) SPT which identified the Dunmore East site as being more toxic. However, it was not possible to correlate the observed ecotoxicological effects with a specific and/or class of contaminants based on sediment chemistry alone. Therefore porewaters found to elicit significant toxicity (Dunmore East and Alexandra Basin) with the test battery were selected for further TIE assessment with T. battalgiai and the Microtox(R) system. The results of this study have important implications for risk assessment in estuarine and coastal waters in Ireland, where, at present the monitoring of sediment and water quality is predominantly reliant on chemical analysis alone.     

Application of the pressure-state-response framework to perceptions reporting of the state of the New Zealand environment

The Pressure-State-Response framework for environmental reporting was used as a basis to develop a long-term study of people's perceptions of the state of the New Zealand environment. A postal survey of 2000 people, randomly drawn from the New Zealand electoral roll was used to gather data--an effective response rate of 48% was achieved. A range of different resource sectors was examined. We report on New Zealand's air, native animals and plants, and marine fisheries, as well as New Zealand compared to other developed countries. Respondents generally considered that in terms of pressures, states and responses, New Zealand was performing better than other developed countries and that for the resources examined here overall performance was in the adequate to good range, except for marine fisheries. The survey appears to be a useful tool for linking perceptions data into State of the Environment reporting. It also helps identify policy issues where perceptions do not match other scientific evidence or management initiatives. Such findings can be important for the successful implementation of policy measures.     

Arsenic compounds in the haemolymph of the Dungeness crab, Cancer magister, as determined by using HPLC on-line with inductively coupled plasma mass spectrometry

Arsenobetaine, two arsenosugars, dimethylarsinate and several unidentified arsenic species were detected in extracts of the haemolymph of the Dungeness crab, Cancer magister, by using HPLC-ICP-MS. This is the first report of the presence of arsenosugars in the haemolymph/blood of marine animals. Total, extractable and residual arsenic concentrations were determined by ICP-MS. The concentration of total arsenic was in the range of 1.4-3.8 [micro sign]g ml(-1). Nearly all (98%) the arsenic was found to be extractable, and accounted for primarily by arsenobetaine, two arsenosugars and dimethylarsinate. The results demonstrate that arsenic compounds present in the diet of crabs are not fully metabolized in the gut. They are, at least partly, taken up into the haemolymph. The concurrence of arsenobetaine and arsenosugars suggests that the use of repeated haemolymph sampling in crustaceans could facilitate investigations into the kinetics of the biotransformation pathways of arsenic compounds. Finally, the present study clearly demonstrates the unique capabilities of HPLC-ICP-MS for the detection and identification of minor arsenic components amongst the predominant arsenobetaine.     

The Sensitivity of Probabilistic Risk Assessment Results to Alternative Model Structures: A Case Study of Municipal Waste Incineration

Abstract

In this analysis, human health risk due to exposure to municipal waste incinerator emissions is assessed as an example of the application of probabilistic techniques (e.g., Monte Carlo or Latin Hypercube simulations). Incinerator risk assessments are characterized by the dominance of indirect exposure, thus this analysis focuses on exposure via the ingestion of locally grown foods. In addition, since exposure to 2, 3, 7, 8-TCDD drives most incinerator risk assessments, this compound is the subject of the illustrative calculations. An important part of probabilistic risk assessment is determining the relative influence of the input parameters on the magnitude of the variance in the output distribution. This constitutes an important step toward prioritizing data needs for additional research. However, under various possible model forms reflecting incompletely understood aspects of contaminant transport, differences may be observed in estimates of risk, variance in risk, and the relative contributions of individual uncertain and variable inputs to the variance. In this analysis, a sequential structural decomposition of the relationships between the input variables is used to partition the variance in the output (i.e., risk) to identify the most influential contributors to overall variance among them. For comparison, the partitioning of variance is repeated, using techniques of multivariate regression. In summary, this study considers the degree to which results of a probabilistic assessment are contingent on critical model assumptions about the representation of deposition velocity. Specifically, this analysis assesses the impact on the results of uncertainty about the best model of the vapor/particle partitioning behavior of semi-volatile airborne pollutants.     

Consumer attitudes regarding environmentally sustainable wine: an exploratory study of the New Zealand marketplace

Previous research has suggested that consumers are becoming increasingly concerned by the effects of conventional agricultural food production practices on human health and environmental wellbeing. This study sought to understand whether environmentally sustainable practices in the vineyard would equate to advantages in the wine marketplace. Structured questionnaires were used to ascertain the views of wine consumers in Christchurch, New Zealand. The findings of this study indicate that consumers have a strong demand for wine which is produced using “green” production practices. Consumers believe that the quality of sustainable wine will be equal to or better than conventionally produced wine, and they are prepared to pay a higher price for this wine.     

Subsurface patch of a dinoflagellate (Ceratium tripos) off Southern California: Patch length,growth rate,associated vertically migrating species

Ceratium tripos dominated a multi-species dinoflagellate patch in the sub-surface chlorophyll maximum in August 1978 on the Southern California shelf. The specific growth rate () ofC. tripos averaged 0.25 d^-1. Patch length was about 45 km along the shelf. Several members of the subsurface dinoflagellate assemblage were also present in surface samples, but only during the daytime. These apparent vertical migrators includedProrocentrum micans, C. furca, Gonyaulax polyedra and other less common forms. The growth ofC. tripos in the California patch is compared with that in aC. tripos patch off New York in 1976.