Cumulative effects of natural and anthropogenic disturbances on the forest carbon balance in the oil sands region of Alberta, Canada; a pilot study (1985-2012).

BACKGROUND: Assessing cumulative effects of anthropogenic and natural disturbances on forest carbon (C) stocks and fluxes, because of their relevance to climate change, is a requirement of environmental impact assessments (EIAs) in Canada. However, tools have not been developed specifically for these purposes, and in particular for the boreal forest of Canada, so current forest C assessments in EIAs take relatively simple approaches. Here, we demonstrate how an existing tool, the Generic Carbon Budget Model (GCBM), developed for national and international forest C reporting, was used for an assessment of the cumulative effects of anthropogenic and natural disturbances to support EIA requirements. We applied the GCBM to approximately 1.3 million ha of upland forest in a pilot study area of the oil sands region of Alberta that has experienced a large number of anthropogenic (forestry, energy sector) and natural (wildfire, insect) disturbances. RESULTS: Over the 28 years, 25% of the pilot study area was disturbed. Increasing disturbance emissions, combined with declining net primary productivity and reductions in forest area, changed the study area from a net C sink to a net C source. Forest C stocks changed from 332.2 Mt to 327.5 Mt, declining by 4.7 Mt at an average rate of 0.128 tC ha-1 yr-1. The largest cumulative areas of disturbance were caused by wildfire (139,000 ha), followed by the energy sector (110,000 ha), insects (33,000 ha) and harvesting (31,000 ha) but the largest cumulative disturbance emissions were caused by the energy sector (9.5 Mt C), followed by wildfire (5.5 Mt C), and then harvesting (1.3 Mt C). CONCLUSION: An existing forest C model was used successfully to provide a rigorous regional cumulative assessment of anthropogenic and natural disturbances on forest C, which meets requirements of EIAs in Canada. The assessment showed the relative importance of disturbances on C emissions in the pilot study area, but their relative importance is expected to change in other parts of the oil sands region because of its diversity in disturbance types, patterns and intensity. Future assessments should include peatland C stocks and fluxes, which could be addressed by using the Canadian Model for Peatlands.

Spatially-integrated estimates of net ecosystem exchange and methane fluxes from Canadian peatlands.

BACKGROUND: Peatlands are an important component of Canada's landscape, however there is little information on their national-scale net emissions of carbon dioxide [Net Ecosystem Exchange (NEE)] and methane (CH4). This study compiled results for peatland NEE and CH4 emissions from chamber and eddy covariance studies across Canada. The data were summarized by bog, poor fen and rich-intermediate fen categories for the seven major peatland containing terrestrial ecozones (Atlantic Maritime, Mixedwood Plains, Boreal Shield, Boreal Plains, Hudson Plains, Taiga Shield, Taiga Plains) that comprise > 96% of all peatlands nationally. Reports of multiple years of data from a single site were averaged and different microforms (e.g., hummock or hollow) within these peatland types were kept separate. A new peatlands map was created from forest composition and structure information that distinguishes bog from rich and poor fen. National Forest Inventory k-NN forest structure maps, bioclimatic variables (mean diurnal range and seasonality of temperatures) and ground surface slope were used to construct the new map. The Earth Observation for Sustainable Development map of wetlands was used to identify open peatlands with minor tree cover. RESULTS: The new map was combined with averages of observed NEE and CH4 emissions to estimate a growing season integrated NEE (± SE) at - 108.8 (± 41.3) Mt CO2 season-1 and CH4 emission at 4.1 (± 1.5) Mt CH4 season-1 for the seven ecozones. Converting CH4 to CO2 equivalent (CO2e; Global Warming Potential of 25 over 100 years) resulted in a total net sink of - 7.0 (± 77.6) Mt CO2e season-1 for Canada. Boreal Plains peatlands contributed most to the NEE sink due to high CO2 uptake rates and large peatland areas, while Boreal Shield peatlands contributed most to CH4 emissions due to moderate emission rates and large peatland areas. Assuming a winter CO2 emission of 0.9 g CO2 m-2 day-1 creates an annual CO2 source (24.2 Mt CO2 year-1) and assuming a winter CH4 emission of 7 mg CH4 m-2 day-1 inflates the total net source to 151.8 Mt CO2e year-1. CONCLUSIONS: This analysis improves upon previous basic, aspatial estimates and discusses the potential sources of the high uncertainty in spatially integrated fluxes, indicating a need for continued monitoring and refined maps of peatland distribution for national carbon and greenhouse gas flux estimation.

Transportation of market-weight pigs: II. effect of season and location within truck on behavior with an eight-hour transport.

Transportation of pigs to slaughter has the potential to negatively impact animal welfare, particularly in hot temperatures and over long transport durations. The objective of this experiment was to determine if season and location within vehicle influenced the behavior of market-weight pigs during loading, transit, unloading, and lairage after a long-distance trip to slaughter. On a pot-belly truck, 1,170 pigs were transported (n = 195 pigs/wk in 7 experimental compartments) for 8 h to a commercial abattoir in summer (6 wk) and winter (5 wk). Pig behavior was observed at loading, in transit, at unloading, and in lairage. Handler intervention at loading was observed, and the time to load and unload was recorded. Although season did not (P = 0.91) affect loading time, more prods (P = 0.014) were necessary to load pigs in summer than winter. Loading in winter also tended to be longer (P = 0.071) into compartments involving internal ramps. In transit, more pigs (P = 0.025) were standing in winter compared with summer. Unloading took longer (P < 0.006) in winter than in summer and from compartments where pigs had to negotiate ramps and 180° turns. Furthermore, pigs in summer experienced more slipping (P = 0.032), falling (P = 0.004), overlapping (P < 0.001), and walking backward (P < 0.001) than pigs in winter. Pigs unloading from compartments with internal ramps slipped more (P < 0.0001) than other pigs. Season influenced latency to rest in lairage, with those transported in summer resting sooner (P < 0.0001) than those in winter. In conclusion, season and location within trucks differentially affect pig behavior before, during, and after long-distance transportation. Differences in lighting and temperature between seasons and the inclusion of internal ramps within vehicles may play important roles in the welfare of pigs transported to slaughter.

Wound patterns: detection, documentation and analysis.

Bruises and other injuries located in skin can play a valuable role in the forensic investigation of a crime. This paper present details outlining how forensic odontology can be useful in detecting, documenting and analyzing such patterned injuries. In addition, four illustrated case histories are included.

Concurrent verrucous carcinomas of the lip and buccal mucosa.

Florid oral papillomatosis presents a picture of multiple squamous papillary lesions found in the oral pharynx. Multiple risk factors associated with the development of these lesions include possible association with papilloma virus, the use of tobacco products, and chronic inflammation or irritation such as that caused by poorly fitted dentures. The major risk factor of these benign squamous lesions is the dedifferentiation into a well-differentiated verrucous carcinoma. However, treatment in the early stage of the disease is usually successful. Surgical excision has been favored as the initial approach. The use of radiotherapy for verrucous carcinoma is controversial. In numerous reported cases dedifferentiation of the tumor has produced an anaplastic squamous cell carcinoma. More recent articles, however, indicate that the risk for dedifferentiation of verrucous carcinoma due to radiotherapy may be overstated.

The detection and documentation of trace wound patterns by use of an alternative light source.

This article is a discussion of the use of narrow-band light sources coupled with cameras equipped with band-pass filters to document patterned injuries on human skin. Several case reports are included.

Basosquamous carcinoma of the head and neck.

Clinical experience with two cases of basosquamous are described. Wide surgical excision is the preferred method of treatment. In some cases, however, radiation therapy or chemotherapy may be useful treatment adjuncts. Unfortunately, prognosis is poor.

Polycythemia vera, primary hyperparathyroidism, and dysplastic nevus syndrome: report of a case.

Polycythemia vera and primary hyperparathyroidism is diagnosed in a patient with dysplastic nevus syndrome. A 59-year-old white man is noted to have numerous pigmented lesions found predominantly over the upper aspect of the back and chest. A biopsy revealed the atypical nevi found in dysplastic nevus syndrome. Over a 13-year period, three superficial spreading malignant melanomas were excised. The patient subsequently had polycythemia vera and primary hyperparathyroidism develop. Atypical pigmented skin lesions were not seen in family members, although two family members died of metastatic malignant neoplasms, one from endometrial carcinoma and the second from prostatic adenocarcinoma.

Neonatal lupus: a case report.

An infant boy born to an asymptomatic mother was found to have typical cutaneous and serologic findings of the neonatal lupus syndrome. Anti-Ro and anti-La antibodies were detected in both the mother and the child. Evaluation of the maternal grandmother who had been diagnosed with "lupus" was nondiagnostic.