The impact of forest to urban land conversion on streamflow, total nitrogen, total phosphorus, and total organic carbon inputs to the converse reservoir, Southern Alabama, USA

High total organic carbon (TOC) concentrations in Converse Reservoir, a water source for Mobile, Alabama, have concerned water treatment officials due to the potential for disinfection byproduct (DBP) formation. TOC reacts with chlorine during drinking water treatment to form DBPs. This study evaluated how increased urbanization can alter watershed-derived total nitrogen (TN), total phosphorus (TP) and TOC inputs to the Converse Reservoir. Converse Watershed, on the urban fringe of Mobile, is projected to undergo urbanization increasing watershed urban land from 3% in 1992 to 22% urban land by 2020. A pre-urbanization scenario using 1992 land cover was coupled with 2020 projections of land use. The Loading Simulation Program C++ watershed model was used to evaluate changes in nutrient concentrations (mg L^?1) and loads (kg) to Converse Reservoir. Urban and suburban growth of 52 km² simulated from 1991 to 2005 (15 year) caused overall TN and TP loads to increase by 109 and 62%, respectively. Simulated urban growth generally increased monthly flows by 15%, but resulted in lower streamflows (2.9%) during drought months. Results indicate that post-urbanization median TN and TP concentrations were 59 and 66% higher than corresponding pre-urbanization concentrations, whereas TOC concentrations were 16% lower. An increase in urban flow caused TOC loads to increase by 26%, despite lower post-urbanization TOC concentrations.     

Understanding the planner’s role in lookahead construction planning

Capacity planning is instrumental in production planning as the variability witnessed in construction projects complicates the planner’s role in achieving a balance between weekly task load and available resources. The purpose of this article is to assess the effects of capacity planning on a project’s time and cost performance and to inform planners on the pitfalls of uninformed capacity planning. A simulation model is developed to test several project scenarios against different capacity planning methods. Cost, time and planning quality measures are developed to track project’s performance throughout the construction period. Results show that the planner’s choice of capacity planning method and the type of project both affect a project’s cost and duration. Interestingly, informed planners who are aware of a project’s characteristics are able to achieve the best balance between weekly load and capacity. They are able to reduce incurred costs wasted on idle resources without significantly affecting the construction period.     

Rethinking work-health models for the new global economy: a qualitative analysis of emerging dimensions of work

Technology change, rising international trade and investment, and increased competition are changing the organization, distribution and nature of work in industrialized countries. To enhance productivity, employers are striving to increase innovation while minimizing costs. This is leading to an intensification of work demands on core employees and the outsourcing or casualization of more marginal tasks, often to contingent workers. The two prevailing models of work and health - demand-control and effort-reward imbalance - may not capture the full range of experiences of workers in today's increasingly flexible and competitive economies. To explore this proposition, we conducted a secondary qualitative analysis of interviews with 120 American workers [6]. Our analysis identifies aspects of work affecting the quality of workers' experiences that are largely overlooked by popular work-health models: the nature of social interactions with customers and clients; workers' belief in, and perception of, the importance of the product of their work. We suggest that the quality of work experiences is partly determined by the objective characteristics of the work environment, but also by the fit of the work environment with the worker's needs, interests, desires and personality, something not adequately captured in current models.     

Precarious employment experiences and their health consequences: towards a theoretical framework

Fundamental shifts in the structure of labour markets, work systems, and employment relations of industrialized countries have outpaced changes in legislative, social and political mechanisms. As a result, a growing number of workers are exposed to precarious employment experiences, which we define as experiences that give rise to instability, lack of protection, insecurity, and social and economic vulnerability. These experiences represent a potentially significant occupational health risk. Our central objective is to develop a detailed framework that outlines the key aspects of work experiences that makes them precarious, and to consider links between these aspects and downstream health effects.     

The relationship between different social expenditure schemes and poverty,inequality and economic growth

In this article, we study how social expenditure is related to poverty, income inequality and GDP growth. Our main contribution is to disentangle these relationships by the following social expenditure schemes: 1) “old age and survivors”, 2) “incapacity”, 3) “health”, 4) “family”, 5) “unemployment and active labour market policies” and 6) “housing and others”. For this purpose, we employ OLS and 2SLS regression models using a panel data set for 22 Member States of the European Union from 1990 until 2015. We find total public social expenditure to be negatively related to poverty and inequality, but not related to GDP growth. The results vary substantially between the different social expenditure schemes, which makes more accurate targeting possible.     

Effects of off-road vehicles on reproductive success of pine snakes (<Emphasis Type="Italic">Pituophus melanoleucus</Emphasis>) in the New Jersey pinelands

Considerable attention has been devoted to the effects of people and their vehicles on birds and mammals, but possible effects on reptiles in populated areas have received less attention. Moreover, the effects of human activities on reptile reproductive success itself has been harder to demonstrate. This paper examines the effect of management of off-road vehicles in New Jersey’s pinelands on the reproductive success of pine snakes (Pituophus melanoleucus) from 1986 to 2005. We used the percentage of snakes in each hibernaculum that were young of the year (hatchlings) as an indicator of reproductive success, and compared this percent for five hibernacula that were in an area with varying degrees of off-road vehicle (ORV) disturbance, with 12 hibernacula in areas with no ORV disturbances (reference sites). This percent took into account differences in absolute numbers from one location to another, and over time due to hibernacula destruction (by people or predators) and natural variations (food supply). The ORV pressure in the pinelands is intense because it lies within the most densely populated urban area in the United States. Although the number of snakes in the reference hibernacula varied over the years from 46 to 63, the percent of young in these hibernacula did not vary significantly over the 20 year period (21–29%). In contrast, the percent-young in the disturbed sites differed significantly in years without ORV disturbance (28%) compared to those with ORV disturbance (15 and 16%, P < 0.01). Further, there were no differences between the percent of young in the reference sites and those in the disturbed site in years without ORV disturbance. ORV disturbance ceased only with the creation of large dirt berms coupled with fences that could not be easily broken. These data indicate the importance of having detailed population data on pine snakes in hibernacula, on ORV use (or indications of such use), and of managing ORV use to protect sensitive populations. Maintenance of healthy pine snake populations in urban areas may require continued adaptive management.