Perceptions of Small Private Forest Owner’s Vulnerability and Adaptive Capacity to Environmental Disturbances and Climate Change: Views from a Heterogeneous Population in Southern Quebec,Canada

A study on the perception of vulnerability and adaptive capacity to climate change (CC) was realised among 27 small private forest owners (SPFOs) of a region in southern Quebec. In-depth semi-structured interviews were conducted with SPFOs of diverse profiles to better understand their perception of environmental disturbances and their needs to improve forest management in relation to global change and more precisely to CC. The main purpose of the research was to better understand whether perceptions of vulnerability and adaptive capacity to CC can constitute a barrier to proactive actions toward adaptation. Qualitative data shows a spectrum of attitudes and perceptions which highlight how SPFOs identify different potential and actual disturbances and assess the risk they represent for their forest-based activities. It shows how place-based experiences of environmental disturbances shape perceptions of vulnerability and capacity to adapt to disturbances. Factors such as access to financial resources and perceived resilience of forest ecosystem influence perceived adaptive capacity. Most SPFOs who participated in the research do not perceive their forest or forest-based activities to be vulnerable to CC, which may constitute a barrier to proactive adaptation to CC. The awareness of CC as a general phenomenon does necessarily translate into adaptation in forestry practices. Yet, many participants expressed a need for better access to knowledge and financial support to improve adaptive capacities to CC and broader environmental or economic stressors.     

The ABCB1-1Δ mutation is not responsible for subchronic neurotoxicity seen in dogs of non-collie breeds following macrocyclic lactone treatment for generalized demodicosis

P-glycoprotein (P-gp), encoded by the multiple drug resistance gene ABCB1 (also known as MDR1 ), is an integral component of the blood brain barrier crucial in limiting drug uptake into the central nervous system. Altered expression or function of P-gp, as seen in dogs of the collie lineage homozygous for the nt228(del4) mutation of the ABCB1 gene ( ABCB1-1Δ ), can result in potentially fatal neurotoxicosis, especially following administration of systemic macrocyclic lactones (SML). Occasionally, dogs from unrelated breeds develop subchronic signs of neurotoxicity when receiving SML to treat generalized demodicosis. It is possible that these dogs are heterozygous carriers of the ABCB1-1Δ mutation, resulting in decreased P-gp activity and central neurotoxicosis. Cheek swabs were collected from 28 dogs with generalized demodicosis that had shown subchronic signs of neurotoxicity following daily oral administration of ivermectin or other SML. Ten of these animals received concurrent systemic treatment with other confirmed or putative P-gp substrates. After DNA extraction, the relevant portion of the ABCB1 gene was amplified by polymerase chain reaction, and sequenced. Twenty-seven dogs were homozygous normal while one dog was heterozygous for the ABCB1-1Δ mutation. Therefore, with the exception of one dog, the observed neurotoxicity could not be attributed to the ABCB1-1Δ mutation. Possible explanations for the adverse reactions observed include pharmacological interactions (administration of SML with other P-gp substrates or inhibitors), excessively high doses, polymorphisms in P-gp expression, uncharacterized mutations in the ABCB1 gene or in another gene, or phenomena unrelated to the SML–P-gp interaction.     

Estimating potato yield responses from chemical control of early blight in Minnesota

The effect of early blight on tuber yield of two potato (Solanum tuberosum L.) cultivars (Russet Burbank and Norland) was evaluated using number and timing of applications of three chemicals to generate different disease epidemics in 1981 and 1982. Under the non-irrigated farming conditions in Minnesota, there were no significant differences among captafol, triphenyltin hydroxide and maneb-Zn in blight control to increase yield. Of the five spray schedules tested, a 7–10 day spray schedule initiated when blight severity exceeded 0.01%, and a 7–10 day schedule initiated when blight was found above the lower third of the plant, generally gave significant, positive yield responses with all three chemicals. At Rosemount in 1982, the greatest yield increases (relative to unsprayed) obtained were 34.9% and 48.6% in total tuber yields for Norland and Russet Burbank, respectively. At Rosemount in 1982, the highest yield increases (relative to unsprayed) obtained were 92.2% and 56.6% in total tuber yields for Norland and Russet Burbank respectively. At Grand Forks in 1981, the highest yield increases were 126.8% and 34.6% in total tuber yields for Norland and Russet Burbank respectively. Across all three experiments, maximum yield losses (percentage of [[yield of ‘healthy’—yield of unsprayed check]/yield of ‘healthy’’]) were 58.4% (US #1 tubers) and 55.9% (total tubers) for cv. Norland and 34.4% (US #1 tubers) and 36.2% (total tubers) for cv. Russet Burbank.     

Freshwater mussels as monitors of bacteriological water quality

A species of commercially obtained freshwater mussel (Elliptio complanata) was shown to actively filter, concentrate, and retain fecal coliform (FC) bacteria from a variety of freshwater stream environments. Fecal coliform densities in mussel viscera were maximum within 48 hr of in situ exposure. Significant FC reproduction did not occur in mussel viscera at temperatures below 30 °C. Variation in replicate FC determinations from mussels exposed in situ for 48 hr was less than that obtained directly from water samples. Numbers of FC concentrated in mussel viscera were retained for several hours after FC densities declined in the surrounding water, suggesting the utility of mussels to record recent episodes of fecal pollution.     

Potato yield losses due to early blight in Minnesota fields, 1981 and 1982

In both 1981 and 1982, 51 potato fields were surveyed every 7–10 days for early blight severity and fungicide use. Early blight severity data from each field were used as input to a regression model to estimate yield loss in that field. The model for early maturing potato cultivars was Percent Yield Loss=0.8183+0.6441* (% blight increment between days 56 and 66)+0.6102* (% blight increment between days 66 and 76)+1.3480* (% blight increment between days 76 and 86). The model for late maturing cultivars was Percent Yield Loss=2.1846-4.7734* (% blight on day 56)+0.7440* (% blight on day 76)+ 0.5676* (% blight on day 96). In both 1981 and 1982, early blight was found to be present in all fields of the survey. In 1981, early blight was estimated to have caused mean losses of 6.5% (Red River Valley), 3.7% (Central sands) and 2.3% (Southern muck). In 1982, losses from the same areas were 5.4%, 3.7% and 2.6% respectively. In 1981, individual county losses ranged from 2.3% for Freeborn to 12.9% for Marshall while in 1982 losses were from 2.0% for Freeborn to 6.7% for Clay. Although fungicide use data were incomplete, the county with lowest yield loss had the most fungicide applications.