Winter Flashcards
How does ice cover impact [DO]?
Ice limits atmospheric mixing causing a decrease in [DO].
There is still a little bit of photosynthesis but respiration continues.
Can results in winter kills.
(ENSC 3106 Notes)
What are the Nine Maxims for the Ecology of Cold-Climate Winters proposed by Emily Studd et al (2021)?
Winter is:
1. Colder
2. Frozen
3. Snowier
4. Darker
5. Less productive
6. Variable
7. Deadly
8. Understudied
9. Changing under climate change
How am I defining winter for my research? Why?
The definition of winter for this study will be the general definition proposed by Studd et al. (2021) which defines winter as the three months of the year with the coldest temperatures and shortest days (i.e., December, January, and February in the Northern hemisphere).
Alternative condition-based definitions include aspects that I’ve already seen don’t happen for my system - e.g., one defines it as the period with ice cover but last year my system barely froze.
What are some of the ecological impacts of winter being colder?
Enzyme-mediated processes slow exponentially or cease altogether, and some proteins are denatured in the cold.
Biological membranes lose fluidity and lipids become more viscous or even solidify.
Ectotherms and endotherms have adapted in different ways to deal with the cold.
These direct effects of temperature on the biochemical, cellular, and organismal levels cascade to the ecosystem level, meaning that biological processes and ecological interactions in winter may be fundamentally different from those in other seasons.
(Studd et al, 2021)
What are some of the ecological impacts of winter being frozen?
In water, less-dense ice floats on the surface, partitioning the liquid water from the air, and preventing movement of organisms, gas exchange, modifying light transmission, and minimizing evaporation and heat loss to the atmosphere. Therefore, surface ice can form unfrozen refugia that remain above 0°C. This allows aquatic life to persist and flourish in certain frozen conditions.
However, ice encasement can render water bodies, soil, and near-ground habitats hypoxic.
(Studd et al, 2021)
What are some of the ecological impacts of winter being snowier?
Accumulated snow blocks light transmission, inhibiting photosynthesis in those plants that retain their leaves.
Snow cover buffers air temperature extremes, and its albedo diminishes heating from solar radiation. Therefore, years with less snow expose organisms in soils or aquatic ecosystems to extreme cold, whereas years with deep snow moderate subnivean temperatures but lengthen snow cover duration because it takes longer to thaw in the spring.
(Studd et al, 2021)
What are some of the ecological impacts of winter being darker?
Winter nights are long, and with the albedo of winter snow reflecting more solar radiation back into the atmosphere, many organisms overwinter in microhabitats with reduced light exposure.
Spring-spawning fishes use the combination of winter photoperiod and temperature cues to synchronize energy allocation and the progression of the reproductive cycle.
(Studd et al, 2021)
What are some of the ecological impacts of winter being less productive?
All else being equal, more sunlight leads to more primary production by plants, phytoplankton, and macrophytes, which enables increased secondary and tertiary production by heterotrophs.
In winter, colder temperatures and less light reduce photosynthetic rates, slow metabolism in ectotherms, and increase thermoregulatory costs for endotherms.
(Studd et al, 2021)
What are some of the ecological impacts of winter being variable?
Winters differ in how cold they are, how long they are, between latitudes, and by their geography.
In aquatic systems, wind and water currents determine thermal stratification and ice formation, which, in turn, affect light and nutrient availability.
Weather and climate patterns can also vary within a season.
Whether it is between years or between days, variability defines winter with cascading impacts on organisms, food webs, and ecosystems.
(Studd et al, 2021)
What are some of the ecological impacts of winter being deadly?
Winter is therefore a brutal annual selection event that filters out genotypes and phenotypes unable to endure its many challenges. As a result, winter has shaped the biology of many species, whether through the evolution of avoidance (migration and hibernation) or through the behavioral and physiological adaptations to winter conditions.
Fishes are susceptible to interacting abiotic and biotic stressors, especially in their first year of life. For example, large-scale fish kills can result from oxygen depletion (i.e., hypoxia or anoxia) in late winter because of nitrification in water bodies isolated from the air by ice or from asphyxiation or stranding because of various ice formations.
(Studd et al, 2021)
Why is winter traditionally understudied?
Field schools normally take place in summer and students usually busy with courses in winter.
Ecology education is focused on examples and theory based on the warmest months of the year, thereby shaping the questions on which our research programs are based.
Can be expensive and dangerous.
Accessibility severely impacted by storms.
(Studd et al, 2021)
What are some of the ecological impacts of winter changing with climate change?
Winter is changing with respect to its duration and intensity.
For example, extreme winter weather, including both extreme cold and extreme warm temperatures within a season, can now be expected at mid-latitudes.
The warming climate is also likely to remove existing winter barriers for invasive species, paving new pathways for dispersion.
(Studd et al, 2021)
Why is studying winter ecology important?
Winter conditions, specifically snow and ice cover, generate a range of ecosystem services that are important for humans, as well as for other organisms. Among the most critical ecosystem services furnished by winter conditions is cooling of land and water surfaces due to snow and ice albedo (helping thwart climate change). Other examples includes its influence on the quality and quantity of drinking water and its importance to hunting, trapping, and fishing.
Winter is relevant to resource managers and conservation practitioners. Minimizing disturbance (e.g., from outdoor recreation or resource development) during periods of hibernation, quiescence, diapause, or general energy conservation can be important to reduce stress and associated energetic expenditure.
Restoration of degraded ecosystems requires understanding the winter tolerances and needs of both plants and animals to ensure the long-term hardiness of recovering populations.
(Studd et al, 2021)
