Evaluation of phenol detoxification by Brassica napus hairy roots, using Allium cepa test

Introduction  

Meristematic mitotic cells of Allium cepa constitute an adequate material for cytotoxicity and genotoxicity evaluation of environmental pollutants, such as phenol, which is a contaminant frequently found in several industrial effluents.     

Arsenic mobility and speciation in a contaminated urban soil are affected by different methods of green waste compost application

Application of green waste compost (GWC) to brownfield land is now common practice in soil restoration. However, previous studies have demonstrated both beneficial and detrimental effects on arsenic and metal mobility. In this paper, trace element behaviour was investigated following GWC application, either as surface mulch to, or mixed into soil from a previously described brownfield site in the U.K. Significant differences in arsenic mobility were observed between treatments. Mulching caused most disturbance, significantly increasing soil pore water As, together with Fe, P, Cr, Ni and dissolved organic carbon, the latter was a critical factor enhancing As mobilization. Arsenate was the main inorganic As species in soil pore water, increasing in concentration over time. An initial flush of potentially more toxic arsenite decreased 4 weeks after compost application. Biological processes appeared to play an important role in influencing As mobility. The results point to the necessity for careful management of As-contaminated soils.     

Climate change vulnerability and resilience: current status and trends for Mexico

Climate change alters different localities on the planet in different ways. The impact on each region depends mainly on the degree of vulnerability that natural ecosystems and human-made infrastructure have to changes in climate and extreme meteorological events, as well as on the coping and adaptation capacity toward new environmental conditions. This study assesses the current resilience of Mexico and Mexican states to such changes, as well as how this resilience will look in the future. In recent studies (Moss et al. in Vulnerability to climate change: a quantitative approach. Pacific Northwest National Laboratory, Washington DC, 2001; Brenkert and Malone in Clim Change 72:57–102, 2005; Malone and Brenkert in Clim Change 91:451–476, 2008), the Vulnerability–Resilience Indicators Model (VRIM) is used to integrate a set of proxy variables that determine the resilience of a region to climate change. Resilience, or the ability of a region to respond to climate variations and natural events that result from climate change, is given by its adaptation and coping capacity and its sensitivity. On the one hand, the sensitivity of a region to climate change is assessed, emphasizing its infrastructure, food security, water resources, and the health of the population and regional ecosystems. On the other hand, coping and adaptation capacity is based on the availability of human resources, economic capacity, and environmental capacity. This paper presents two sets of results. First, we show the application of the VRIM to determine state-level resilience for Mexico, building the baseline that reflects the current status. The second part of the paper makes projections of resilience under socioeconomic and climate change and examines the varying sources and consequences of those changes. We used three tools to examine Mexico’s resilience in the face of climate change, i.e., the baseline calculations regarding resilience indices made by the VRIM, the projected short-term rates of socioeconomic change from the Boyd–Ibarrarán computable general equilibrium model, and rates of the IPCC-SRES scenario projections from the integrated assessment MiniCAM model. This allows us to have available change rates for VRIM variables through the end of the twenty-first century.     

Inclusive education for children with disabilities in a refugee camp

Children in refugee camps, and particularly those with disabilities, face unique challenges in accessing education and are at high risk of being marginalised. Best practices suggest that main-streaming is the optimal strategy for serving students with disabilities. This study examines the extent to which mainstreaming in a refugee camp helps to promote children's prosocial behaviours, taking into account their emotional and behavioural problems. In Kakuma Refugee Camp, Kenya, researchers collected data from the parents of children currently enrolled in special needs education centres (n=65) and from those formerly enrolled at these facilities who transitioned to mainstream classrooms (n=81). Children in mainstream schools functioned better in terms of prosocial behaviours, but this relationship disappeared when factoring in children's emotional and behavioural difficulties. In the context of a refugee camp, mainstreaming alone is not likely to help children's psychosocial and educational functioning, which requires dedicated supports, appropriate facilities and infrastructure, and a dual focus on disability-specific and disability-inclusive initiatives.     

The development of psychological contract breach and violation: a longitudinal study

This study examines factors affecting employees' perceptions that their psychological contract has been breached by their organization, and factors affecting whether this perception will cause employees to experience feelings of contract violation. Data were obtained from 147 managers just prior to their beginning of new job (time 1) and 18 months later (time 2). It was found that perceived contract breach at time 2 was more likely when organizational performance and self‐reported employee performance were low, the employee had not experienced a formal socialization process, the employee had little interaction with organizational agents prior to hire, the employee had a history of psychological contract breach with former employers, and the employee had many employment alternatives at the time of hire. Furthermore, perceived breach was associated with more intense feelings of violation when employees both attributed the breach to purposeful reneging by the employer and felt unfairly treated in the process. Theoretical and practical implications of these results are discussed. Copyright © 2000 John Wiley & Sons, Ltd.     

A bioeconomic model of afforestation in Southern Ontario: Integration of fiber,carbon and municipal biosolids values

This study explores the economic attractiveness of afforestation as a strategy for the joint production of fibre, carbon storage and biosolids (treated municipal sewage sludge) disposal for municipalities in Southern and Central Ontario, Canada. We use a spatial, stochastic model, the Canadian Forest Service Afforestation Feasibility Model (CFS-AFM), to simulate a range of spatial biosolids application scenarios in hybrid poplar afforestation projects. Results suggest that such joint afforestation strategies could be financially attractive. Significant cost savings can be expected through decreases in transportation distances and avoided waste disposal fees. Sensitivity analysis is used to examine the effects of variations in critical model parameters on net present values. Our findings indicate that waste disposal savings from application of biosolids on hybrid poplar plantations combined with incentives for landowners to sequester carbon can easily compete with agricultural land rental values in some regions of Ontario. Social acceptance of this kind of activity, however, may be an impediment to adoption.     

Climate Change, Coral Reef Ecosystems, and Management Options for Marine Protected Areas

Marine protected areas (MPAs) provide place-based management of marine ecosystems through various degrees and types of protective actions. Habitats such as coral reefs are especially susceptible to degradation resulting from climate change, as evidenced by mass bleaching events over the past two decades. Marine ecosystems are being altered by direct effects of climate change including ocean warming, ocean acidification, rising sea level, changing circulation patterns, increasing severity of storms, and changing freshwater influxes. As impacts of climate change strengthen they may exacerbate effects of existing stressors and require new or modified management approaches; MPA networks are generally accepted as an improvement over individual MPAs to address multiple threats to the marine environment. While MPA networks are considered a potentially effective management approach for conserving marine biodiversity, they should be established in conjunction with other management strategies, such as fisheries regulations and reductions of nutrients and other forms of land-based pollution. Information about interactions between climate change and more “traditional” stressors is limited. MPA managers are faced with high levels of uncertainty about likely outcomes of management actions because climate change impacts have strong interactions with existing stressors, such as land-based sources of pollution, overfishing and destructive fishing practices, invasive species, and diseases. Management options include ameliorating existing stressors, protecting potentially resilient areas, developing networks of MPAs, and integrating climate change into MPA planning, management, and evaluation.     

Herd no More: Livestock Husbandry Policies and the Environment in Israel

Livestock production in both industrial systems, where livestock are packed tightly together, and in highly traditional systems, where a shepherd follows her herd in dispersed rangelands, are cited as key contributors in some of the most acute environmental problems around the globe. Israel is one of the few countries where both of these systems exist, with surprisingly little contact between them. The environmental impact of the sectors were examined along with Israel’s public policies in the field. While historically, much attention has been placed on the contribution of the Bedouin pastoralists to desertification and erosion, this may be linked to historic misapprehension about actual impacts of goats on local rangelands as well as political motivations and concerns about losing national sovereignty over large areas of rangelands. The true environmental effects appear to be minor. A far more critical concern is water pollution caused by the industrial sector of livestock production—an issue that recently has attracted considerable government attention and investment in a successful dairy infrastructure initiative. The divisions between governmental supports for the Jewish and Arab sectors of livestock management are inconsistent with efficient environmental management. Policies should be designed to encourage Bedouin to find ways to sustainably continue their traditional livestock husbandry practises, which today are largely associated with ecological benefits and constitute a unique cultural asset for Israel and the world.     

Nonylphenol algal bioaccumulation and its effect through the trophic chain

Nonylphenol is a metabolic intermediate from the microbial transformation of detergents used worldwide. While nonylphenol shows some acute toxicity, it is also able to mimic important hormones resulting in the disruption of several processes by interfering with the signals that control the overall physiology of the organism. The effect of the pollutant nonylphenol (NP) through the trophic chain was studied. Microalgae Isochrysis galbana was able to bioconcentrate NP 6940 times, where 77% of initial NP (100microgl(-1)) is accumulated intracellularly after 1-h incubation. Crustacean Artemia fransiscana showed 25% higher growth when fed with NP-rich algae. However, Artemia metabolized almost all NP ingested and only traces of NP could be found in the organism, eliminating future NP effects. Zebrafish (Brachydanio rerio) were affected by the presence of 171microgg(-1) of NP in the diet, showing higher levels of the hormone vitellogenin and lower levels of cytochrome P450 activity. These results showed that organisms placed in the first level of trophic chain are able to significantly bioconcentrate the pollutant and endocrine disruptor NP. These grassed organisms affect the growth of crustacean. Moreover, the organisms placed on the top of some trophic chains, such as fish, could be affected by the presence of NP in their food, in both the hormone levels and metabolic enzymes. This work shows that the environmental presence of NP should be considered as a risk for the organisms living in an ecosystem.     

Evaluating Kriging as a Tool to Improve Moderate Resolution Maps of Forest Biomass

The USDA Forest Service, Forest Inventory and Analysis program (FIA) recently produced a nationwide map of forest biomass by modeling biomass collected on forest inventory plots as nonparametric functions of moderate resolution satellite data and other environmental variables using Cubist software. Efforts are underway to develop methods to enhance this initial map. We explored the possibility of modeling spatial structure to make such improvements. Spatial structure in the field biomass data as well as in residuals from the map was investigated across 18 ecological zones in the Interior Western U.S. Exploratory tools included directional graphs of summary statistics, three dimensional maps, Moran’s I correlograms, and variograms. Where spatial pattern was present, field and residual biomass were kriged, and predictions made for an independent test set were evaluated for improvement over predictions in the initial biomass map. While kriging has some potential benefit when analyzing the field data and exploring spatial structure, kriging residuals resulted in little or no improvement in the initial biomass map developed using Cubist software. Stationarity assumptions, variogram behavior, and appropriate model fitting strategies are discussed.