A process-based model designed for filling of large data gaps in tower-based measurements of net ecosystem productivity

In this paper we present a simple hybrid gap-filling model (GFM) designed with a minimum number of parameters necessary to capture the ecological processes important for filling medium-to-large gaps in Flux data. As the model is process-based, the model has potential to be used in filling large gaps exhibiting a broad range of micro-meteorological and site conditions. The GFM performance was evaluated using “Punch hole” and extrapolation experiments based on data collected in west-central New Brunswick. These experiments indicated that the GFM is able to provide acceptable results (r² > 0.80) when >500 data points are used in model parameterization. The GFM was shown to address daytime evolution of NEP reasonably well for a wide range of weather and site conditions. An analysis of residuals indicated that for the most part no obvious trends were evident; although a slight bias was detected in NEP with soil temperature. To explore the portability of the GFM across ecosystem types, a transcontinental validation was conducted using NEP and ancillary data from seven ecosystems along a north-south transect (i.e., temperature–moisture gradient) from northern Europe (Finland) to the Middle East (Israel). The GFM was shown to explain over 75% of the variability in NEP measured at most ecosystems, which strongly suggests that the GFM maybe successfully applied to forest ecosystems outside Canada.     

Computational analysis of turbulence enhancement in a compression ignition engine with modified inlet design

Environmental Science and Pollution Research - This study aims to enhance the turbulence of direct injection (DI) diesel engine by modifying the inlet manifold design with an inclined nozzle-like...     

Adaptive Capacity and Social-Environmental Change: Theoretical and Operational Modeling of Smallholder Coffee Systems Response in Mesoamerican Pacific Rim

Communities who rely directly on the natural environment for their survival typically have developed risk management strategies to enable them to avoid dangerous thresholds of change to their livelihoods. Development policy appropriate for natural resource-based communities requires an understanding of the primary drivers of social-ecological change, the ways in which affected households autonomously respond to such drivers, and the appropriate avenues for intervention to reduce vulnerability. Coffee has been, and still remains, one of the most important commodities of the Mesoamerican region, and hundreds of thousands of smallholder households in the region are dependent in some way on the coffee industry for their livelihood stability. We used the Analytical Network Process to synthesize expert knowledge on the primary drivers of livelihood change in the region as well as the most common household strategies and associated capacities necessary for effective response. The assessment identified both gradual systemic processes as well as specific environmental and market shocks as significant drivers of livelihood change across the region. Agronomic adjustments and new forms of social organization were among the more significant responses of farmers to these changes. The assessment indicates that public interventions in support of adaptation should focus on enhancing farmers’ access to market and technical information and finance, as well as on increasing the viability of farmers’ organizations and cooperatives.     

Core self‐evaluations in Japan: relative effects on job satisfaction,life satisfaction,and happiness

The present study tested, in a non‐Western culture (Japan), the relative validity in predicting job satisfaction, life satisfaction, and happiness of core self‐evaluations (CSE), positive and negative affectivity (PA/NA), and the Neutral Objects Satisfaction Questionnaire (NOSQ). Consistent with previous results in primarily Western cultures, the four lower‐order traits that comprise CSE—self‐esteem, generalized self‐efficacy, locus of control, and neuroticism—indicated a higher‐order factor. While each lower‐order trait was itself related to the study's criteria, the CSE concept displayed in general, higher correlations with the dependent variables, and explained incremental variance in two of the study's three outcomes beyond PA, NA, and the NOSQ. These results indicate initial support for the generalizability of CSE in a culture that differs in many respects from Western cultures, and suggest that judgments of satisfaction and happiness in a non‐Western culture have a dispositional source. Copyright © 2005 John Wiley & Sons, Ltd.     

How far are biodiversity loss and climate change similar as policy issues?

Climate change and biodiversity loss have a central position in policy debate about global environmental change; however, of the two, climate change has a higher profile. This paper explores the similarities and difference between the two issues. Climate change is better defined and better understood as a policy issue, it is underpinned by a strong scientific consensus and practical units of measurement (CO₂ and financial impacts), and mitigation involves a key economic sector in energy. Biodiversity loss is less easily understood, more diffuse and less tangible, and policy responses do not engage major economic sectors. We argue that these differences contribute to the higher public and policy profile of climate change and can inform attempts to enhance responses to the problem of biodiversity loss.     

Effects of Sulfur Dioxide and Nitric Oxide on Mercury Oxidation and Reduction under Homogeneous Conditions

Abstract

This paper is particularly related to elemental mercury (Hg⁰) oxidation and divalent mercury (Hg²⁺) reduction under simulated flue gas conditions in the presence of nitric oxide (NO) and sulfur dioxide (SO₂). As a powerful oxidant and chlorinating reagent, Cl₂ has the potential for Hg oxidation. However, the detailed mechanism for the interactions, especially among chlorine (Cl)-containing species, SO₂, NO, as well as H₂O, remains ambiguous. Research described in this paper therefore focused on the impacts of SO₂ and NO on Hg⁰ oxidation and Hg²⁺ reduction with the intent of unraveling unrecognized interactions among Cl species, SO₂, and NO most importantly in the presence of H₂O. The experimental results demonstrated that SO₂ and NO had pronounced inhibitory effects on Hg⁰ oxidation at high temperatures when H₂O was also present in the gas blend. Such a demonstration was further confirmed by the reduction of Hg²⁺ back into its elemental form. Data revealed that SO₂ and NO were capable of promoting homogeneous reduction of Hg²⁺ to Hg⁰ with H₂O being present. However, the above inhibition or promotion disappeared under homogeneous conditions when H₂O was removed from the gas blend.     

In vitro methylation of DNA by the fumigant methyl bromide

Abstract

Investigations have shown that the physical state of the DNA strongly influences the pattern of methylation observed when DNA or a substance containing DNA is treated with the fumigant methyl bromide. 1‐Methyl‐adenine and 7‐methylguanine were identified, after hydrolysis, as the major methylated bases of DNA which had been treated in the solid state. 3‐Methylcytosine, 3‐methyladenine and 7‐methyladenine were found as minor products. The overall methylation pattern was similar to that observed earlier for DNA of maize and wheat which had been fumigated. In contrast, when buffer solutions of DNA were treated with methyl bromide, the N‐7 position of guanine was the major site and the N‐3 position of adenine was the second most important site of methylation. This result corresponds to that previously observed in similar studies with buffer solutions of DNA and other methylating agents.