Autumn destabilization of deep porewater CO2 store in a northern peatland driven by turbulent diffusion

The deep porewater of northern peatlands stores large amounts of carbon dioxide (CO2). This store is viewed as a stable feature in the peatland CO2 cycle. Here, we report large and rapid fluctuations in deep porewater CO2 concentration recurring every autumn over four consecutive years in a boreal peatland. Estimates of the vertical diffusion of heat indicate that CO2 diffusion occurs at the turbulent rather than molecular rate. The weakening of porewater thermal stratification in autumn likely increases turbulent diffusion, thus fostering a rapid diffusion of deeper porewater CO2 towards the surface where net losses occur. This phenomenon periodically decreases the peat porewater CO2 store by between 29 and 90 g C m-2 throughout autumn, which is comparable to the peatland's annual C-sink. Our results establish the need to consider the role of turbulent diffusion in regularly destabilizing the CO2 store in peat porewater.

Current forest carbon fixation fuels stream CO2 emissions

Stream CO2 emissions contribute significantly to atmospheric climate forcing. While there are strong indications that groundwater inputs sustain these emissions, the specific biogeochemical pathways and timescales involved in this lateral CO2 export are still obscure. Here, via an extensive radiocarbon (14C) characterisation of CO2 and DOC in stream water and its groundwater sources in an old-growth boreal forest, we demonstrate that the 14C-CO2 is consistently in tune with the current atmospheric 14C-CO2 level and shows little association with the 14C-DOC in the same waters. Our findings thus indicate that stream CO2 emissions act as a shortcut that returns CO2 recently fixed by the forest vegetation to the atmosphere. Our results expose a positive feedback mechanism within the C budget of forested catchments, where stream CO2 emissions will be highly sensitive to changes in forest C allocation patterns associated with climate and land-use changes.

Utilization of the Canadian Incidence Study of Reported Child Abuse and Neglect by child welfare agencies in Ontario

INTRODUCTION

The purpose of this study was to analyze how child maltreatment surveillance data from the Canadian Incidence Study of Reported Child Abuse and Neglect (CIS) is used by senior child welfare decision makers.

METHODS

This triangulation mixed-methods study included quantitative and qualitative methods to facilitate an in-depth exploration from multiple perspectives. We interviewed Ontario child welfare decision makers to measure utilization of the CIS in policy development.

RESULTS

The majority of respondents were aware of the CIS data. Decision makers reported using these data to determine resource allocation, understand reported maltreatment trends and validate findings at their own agencies. Urban agencies used the data more than did rural agencies.

CONCLUSION

This study is the first to triangulate data to understand and improve utilization of child maltreatment surveillance data. The study participants indicated considerable appreciation of the data and also provided ideas for improvements across the surveillance cycle.

Introduction to the "space-control theory of paramedic scene management"

BACKGROUND

Scene management is a critically important aspect of paramedic practice but, to date, there has been no formal research in this area.

OBJECTIVE

To generate a substantive theory of paramedic scene management practice.

METHOD

A grounded theory methodology was used to conduct a qualitative inquiry that involved interviewing paramedics concerning their approach to scene management. Paramedics were selected from rural, suburban and urban settings and were categorised by competence level as novice, experienced and expert.

RESULTS

A theory was generated that describes how paramedics coordinate key specific social processes to establish "space control" at the scene.

CONCLUSION

This study introduces the first formal theory of paramedic scene management and suggests that recognition of this aspect of practice will improve both pre- and in-service educational programming and assist with medical quality assurance.