Archives: Projects

Principle Investigator: Edward Cloutis

Co-Investigators: Anke Kirch, Jillian Golby, Grant Wiseman, Darcy Carter

PROJECT SUMMARY

Climate change is a phenomenon that is receiving increasing worldwide attention. While substantial research has been carried out on the potential effects of climate change in the Canadian Prairies at the regional, provincial, and individual farm levels, no studies have evaluated the socioeconomic impacts of these changes at the community level. In addition, despite the increase in media attention, many people at the community level are still uninformed and confused about the potential biophysical and socioeconomic impacts of climate change. The research presented in this report assessed the potential impacts of climate change on agriculture and forestry, and evaluated the detailed impacts on six rural municipalities in the Canadian prairies. The research project was designed as an evolutionary model, allowing for progressive improvements in functionality and sophistication. An initial model in the form of a software toolwas developed and established: the Socio-Economic Analysis (SEA) model. The model is designed to examine the socioeconomic impacts of climate change on agriculture and forestry in prairie communities and to aid these communities in determining the economic impacts of various adaptation strategies. It is flexible and interactive and can accommodate various standard or user-defined scenarios. The base data used in the SEA model includes biophysical data published by various authors, as well as economic and socioeconomic data from various government agencies. The output from various iterations of the SEA model shows that climate change impacts on agriculture mostly depend on the chosen scenario, while all forestry scenarios agree that grassland and other vegetation types will extent northwards, thereby reducing the amount of boreal forest in the three Prairie provinces.

Final Report Prepared for the Prairie Adaptation Research Collaborative

Daniel J. Archambault, Xiaomei Li, Darren Robinson, John T. O’Donovan, Kurt K. Klein

EXECUTIVE SUMMARY

The dynamics of competition between crops and weeds are affected by environmental conditions, and have been shown to change with CO2 enrichment. Differential responses of C3 and C4 plants to elevated CO2 and temperature may cause shifts in their competitive interactions. There is a need to evaluate the effects of elevated CO2 and temperature on crop/weed competition and herbicide efficacy to develop strategies for agriculture in the face of climate change. The objective of this study was to evaluate the effects of elevated CO2 and temperature on the efficacy of commonly used herbicides and on crop/weed competition. Specifically, the objectives were to:

1. determine the effects of elevated CO2 on the efficacy of herbicides in controlling wild oats, Canada thistle, redroot pigweed, green foxtail, lambsquarters, kochia and common groundsel,
2. study herbicide efficacy at ambient and elevated CO2 levels on wild oats and green foxtail grown in competition with barley,
3. develop a CO2 dose response curve that will be used to establish a timeline of change in herbicide efficacy by taking into account current rates of change in atmospheric CO2,
4. study the interactive effects of elevated CO2 and temperature on herbicide efficacy in wild oats,
5. conduct an economic analysis to provide preliminary monetary values of the effectsof elevated CO2 and temperature on weed/crop competition and herbicide efficacy.

We screened several herbicide/weed combinations and selected crops for effects of elevated CO2 using both greenhouse-based and growth-chamber based gas exposure systems. We found that responses of weeds and crops to increasing CO2 levels were species-specific. Herbicide efficacy can be negatively affected by elevated CO2 and effects were dependent on the mode of action of herbicides, on weed species and on competition. While double-ambient CO2 caused a decrease of 57% in efficacy of the herbicide Fusion applied to wild oats (C3), no effects of elevated CO2 were found when the herbicide was applied to green foxtail (C4). CO2-related reduction in efficacy of Round-up Transorb applied to Canada thistle was reversed when weeds were grown in competition with canola. Dose response experiments showed that efficacy of certain herbicides could be adversely affected at CO2 levels approximately 160 ppm above ambient. Based on these findings, an experiment was designed to study CO2/temperature interactions on growth of wild oats and herbicide efficacy using either ambient levels of CO2 or ambient + 160 ppm and daytime temperature of either 23,26 or 29oC. Daytime temperatures above 23oC decreased growth both in control and herbicide-treated plants. Increasing daytime temperature from 23 to 29oC caused decreased efficacy in the herbicides Fusion and Liberty but not in Assert 300. Decreases in efficacy were greatest at ambient CO2 for Fusion and greatest at ambient + 160 ppm CO2 in Liberty. While analysis of variance did not detect a significant interaction between CO2 and temperature, both elevated CO2 and temperature caused decreased efficacy of the herbicide Liberty on wild oats.

The economic analysis performed using plant growth and herbicide efficacy changes suggested that potential monetary losses due to CO2-induced decreases in herbicide efficacy can be partially or totally overcome by increases in crop yields caused by elevated CO2. Nonetheless,the results also suggest that weed control will be crucial in realizing potential increases in economic yield of crops as atmospheric CO2 concentrations increase. Since yields were not measured directly in this study, several assumptions were made to estimate the expected changes in yields that may occur as a result of the changes in CO2 levels and herbicide efficacies. The changes in biomass caused by increased levels of CO2 were translated into expected changes in yields using three different case scenarios. Case one assumed that yield increases were directly proportional to the biomass increases that occurred. Case two assumed that the increases in yields were half of the increase in biomass. Case three assumed that yields did not increase as biomass levels increased. Further studies on the effects of elevated CO2 and temperature on crop yields and herbicide efficacy are required to diminish the uncertainties in the economic analysis. If effects of climate change on crop/weed competition and herbicide efficacy are common, they will have a significant impact on agriculture.

It was concluded that:

1. The efficacy of herbicides either decreased, increased or did not change when herbicides were applied to weeds grown at elevated CO2.
2. Effects of elevated CO2 on herbicide efficacy may change when weeds are grown in competition with crops.
3. Herbicide efficacy changes were only found to occur at 160 ppm above ambient levels of CO2. According to the current rate of change in atmospheric concentrations of CO2, this corresponds  to approximately 50 years from present.
4. Elevated temperature tended to decrease herbicide efficacy and the effects of temperature and CO2 can be additive.
5. The economic analysis performed using plant growth and herbicide efficacy changes suggest that potential monetary losses due to decreased herbicide efficacy can be partially or totally overcome by increases in crop yields caused by elevated CO2. Nonetheless, the results also suggest that weed control will be crucial in realizing potential increases in economic yield of crops as atmospheric CO2 concentrations increase.
6.  In this study, most of the data used to produce the economic analysis were extrapolations from short-term screening experiments and several assumptions needed to be made. Further             studies on the effects of elevated CO2 and temperature on crop yields and herbicide efficacy are required to diminish the uncertainties in the economic analysis.

G. E. Melville

EXECUTIVE SUMMARY

All major climate-change agenda efforts in recent years echo the need for more empirical scientific information about climate change and adaptation to freshwater ecosystem impacts. The adaptation research undertaken in this study begins the process of providing answers to the general question posed by resource managers and other stakeholders, “What options can we choose from to ensure the sustainability of the aquatic resources under our stewardship?” More specifically, the research results in a systematic methodological framework which resource managers could build on to determine adaptation options for specific lake types, as well as examples with respect to such options.

Research concentrates on the numerous larger lakes in the Boreal Plain which, although they are not necessarily “cold” lakes, tend towards the “cold” end of the temperature spectrum. The biophysical components of these lakes are highly vulnerable and, unlike some of the smallest lakes, which could simply disappear if climate change impacts were extreme, many of the biophysical elements of these lakes would probably continue to exist. The research in this study addresses resources in relation to climate change and adaptation at three levels of ecological organization. The three are lake habitat, intermediate levels in food webs, primarily small-bodied fish species, and large-bodied fish species.

This study focuses primarily on two large-bodied cold-water species, lake whitefish (Coregonus clupeaformis) and lake trout (Salvelinus namaycush), both salmonids. All analyses begin under the umbrella of climate-related total allowable catch, or TAC, probably the most direct, integrative, management tool. Yield calculations per se have been based on relatively simple empirical models, in which fishery yields are related to summer thermal habitats.

Two lakes were selected for inclusion, Lake Winnipeg and Kingsmere Lake, Prince Albert National Park, as examples of a large but relatively shallow water body and a relatively deep system respectively. Lake Winnipeg deserves special attention simply because it is one of the world’s great lakes. Kingsmere Lake provides one of the few examples of a cold, dilute system for which one can investigate process and pattern, in an integrated manner, across a range of trophic or food web levels.

This study offers resource managers the only set of empirical harvesting models for cold freshwater fish which will conserve population structure in the target populations. These models are based on climate-related habitat features. These models substantially improve the precision of previous efforts; more importantly however, they add accuracy through the incorporation of conservation considerations. Continued use of any previous empirical models will ultimately have disastrous effects on all freshwater fisheries, if they haven’t already. The new climate-based TAC models are highly predictive for most lakes, but analyses indicate the model for lake trout may be inadequate for lakes <1000 km2 in surface area. More work is needed in the development of the lake whitefish TAC for all lakes, regardless of size, since sustained yields may yet be overestimated by the model developed in this study. As a great lake, we need to know far more about all aspects of Lake Winnipeg to manage it properly, regardless of the issue or context.

It is probable that we can best adapt to climate change through proper management of our remaining fish stocks. Additional management adaptation requirements include the development  of adequate fishery monitoring programs, few of which exist in the Boreal Plains Ecozone. In the short term, management agencies across the Boreal Plain Ecozone should implement a moratorium on lake trout fishing; this is the only real hope for the lake trout of the ecozone. The management agencies should also implement a comprehensive in-depth assessment of the state of surviving lake trout populations. Lake trout in the Boreal Plain are in a similar situation to that of large carnivores in the Rocky Mountains, where the fate of the “last of the last, not the last of the best” (c.f. P. Paquet) is at stake.

M. Johnston, E. Wheaton, S. Kulshreshtha, V. Wittrock, J. Thorpe

EXECUTIVE SUMMARY

The Canadian Boreal Forest is a mainstay of the Canadian economy, and it has immense social, environmental and intrinsic importance. Canada depends on the boreal forest for many essential products and services including forest products, wildlife habitat, recreation, research, and educational opportunities, and spiritual values. Forestry is an important primary goods-producing industry in the Prairie Provinces. Many of the communities and businesses in the north depend heavily on forest related activities. As the boreal forest is altered by climate change, these values will be compromised in important ways. Climate change is expected to affect boreal forests to a greater degree than other forest types because of its northern location and because boreal forests are more sensitive to temperature.

Currently available information on climate change impacts is presented at global or regional scales and does not provide adequate information for forest and other resource managers to make decisions on changing their management to adapt. Overall objectives of this project are to collect and synthesize information on climate change impacts on western Canada’s boreal forest, and to present the information at spatial and temporal scales meaningful to forest management and planning. Specific objectives of this project are: 1) targeted literature review; 2) conceptual model; 3) sensitivity analyses of landscapes; 4) modelling approaches; 5) adaptation option identification; and 6) communication of results.

The Canada Country Study forest literature review by Wheaton (1997) was updated in several main topic areas including moisture and other climate variables, fire, insects, diseases, and economics. Interactions, knowledge gaps, adaptation options were discussed, and recommendations were developed. A very substantial gap in current boreal forest impacts, adaptations, and vulnerability work is that findings have not been drawn together in any comprehensive way. This is a serious obstacle to determining the vulnerability of the boreal forest and of those communities that rely on the forest. A conceptual model to accomplish this integration is essential and the foundation to further modelling (Figure 1).

We developed and presented a preliminary integrated conceptual model based on the findings from the literature review, meetings, workshops, and an assessment of existing models of various types.The conceptual model highlighted and synthesized the impact of climate change on forest fire frequency and severity; moisture stress and productivity; and forest insect pest outbreaks. Also included is the recognition that climate-induced impacts will occur in association with other land use activities such as timber harvesting, mining development and road construction. These must also be taken into account when assessing the ecological and socio-economic impacts of climate change. Conceptual models were also created to advance research on the effect of climate change on the output of the forest sector and to estimate the economic impacts of climate change on the forest sector. A limitation to this entire work was the lack of published impacts and adaptations papers for this area and subject. This lack is being partly addressed, as additional work done for the Government of Canada’s Climate Change Action Fund and for the Prairie Adaptation Research Collaborative (PARC) is being completed. However, socio-economic aspects, for example, may still be neglected.

Justine Klaver

PROJECT SUMMARY

Climate change could alter the health status, directly or indirectly, of populations on the Canadian Prairies. However, the health effects of climate change on Prairie residents, and short-, medium-, and long-term adaptation measures that will be required, are largely unknown. We invited various stakeholders in four sectors (Government, Industry, Academia, and Public) to participate in Round Table Discussions (RTDs) in order to obtain a balanced perspective for the future directions that research might take regarding human health and climate change. Discussions took place in each Prairie province with the following objectives: to identify meaningful and feasible human health and climate change research questions specific to the Prairie region; to identify resources available for the conduct of research into the relationship between human health and climate change; and, to identify opportunities for public outreach and education regarding adaptation to climate change. Our results indicate that there is a need for greater collaboration between physical sciences and health sciences, a need to better understand future climate scenarios, and a need to understand how these scenarios could affect the health of human populations on the Canadian Prairies. Other significant issues of high priority to Prairie stakeholders were: water quality and quantity, economic effects of climate change, air quality and other pollutants, adaptation capacity posed by the future climate challenges, new disease burdens, agriculture and rural health, and, finally, risk communication and public outreach. The interdependence of adaptation on measures to mitigate climate change could not be ignored in any of the discussions.