In summer, the flora of Nunavik reveals its beauty and diversity. The apparent fragility of these plants is deceptive, for each species has developed special ways of adapting to the harsh climatic extremes of an arctic environment. Here are some of the characteristics of Nunavik’s flora.
The flora of Nunavik, as elsewhere in the Arctic, must adapt to the extreme conditions it is exposed to, the most obvious of which is the cold weather. Plants not only have to deal with harsh winters, but also must survive summer frosts that occur during the growing season, and this presents a real challenge.
To make the most of a short summer and resume vegetative growth without delay, many Nunavik species have low foliage that can take advantage of the heat given off by sun-warmed earth as soon as the snow has melted in spring.
Another adaptation is the production of persistent leaves at the end of summer. These leaves survive the winter and are ready to reactivate photosynthesis with the first mild days of spring. They fall off when new leaves form.
Arctic winds have considerable impact on the flora and the ways it adapts. In winter, the wind has a drying effect and blowing snow is abrasive. Certain plants grow branches close to the soil to create a cushion-like protective zone with their leaves. The air trapped inside this zone can be up to 15°C higher than the surrounding air. Dead leaves play two roles: while still attached, they protect the top of the plant from harsh weather and, when they fall, they enrich the soil, which is often poor. Surprisingly luxuriant plants can sometimes be found growing beside a bird’s nesting site or next to an animal carcass, locations that offer the advantage of additional nutrients.
A good part of Nunavik’s flora consists of perennials, that is, plants that live for several years and flower each summer. Perennials have solid, well-anchored networks of roots or rhizomes, which are horizontal underground stems that can sprout new plants. Since their roots hold the soil in place, perennials limit the devastating effects of frost heaving, when humid ground expands in freezing temperatures. By stabilizing the soil, perennials create a safe environment both for themselves and other plant species.
As a way of adapting to a short growing season, several Nunavik plants form flower buds at the end of summer so as to be ready to bloom with the first warmth of spring. These flowers attract the insects needed for pollination.
Certain saucer-shaped flowers tempt insects with shelter as well as pollen and nectar. With their parabolic curves, these flowers act like thermal and light reflectors, concentrating the sun’s rays at a focal point. On a sunny day, it is not unusual to see an insect warming itself inside a bloom long after it has taken nourishment there. Some of these flowers even track the movement of the sun, which maximizes this effect.
Pollination triggers the process that leads to the production of seeds, some of which will be carried off by arctic winds. Certain plants need only a breeze to disperse their seeds, while others take advantage of arctic gales to extend their territory. More often than not, the seeds come to rest along with dust and other plant bits in snowdrifts, which melt in spring and provide the moisture required for successful germination and seedling development. Other seeds are dispersed by mammals and birds that feed on berries and dry seeds.
Not all plants in Nunavik reproduce by means of seeds. Some of them spread using their rhizomes (underground stems that put down roots at regular intervals), stolons (branches that creep over the ground and send out roots at their tips) and bulblets (little bulbs that take the place of flowers, either entirely or in part).
Although mosses and lichens vary greatly in appearance, they are distinguished from other plants by their lack of roots. They are anchored to the ground by a network of delicate filaments, called rhizines for lichens and rhizoids for mosses. Lichens produce acids that etch rock and thus give the plant a better foothold.
Mosses and lichens are very drought-resistant, absorbing water when it is available and sinking into a dormant state when it is not. Certain lichens can reactivate their metabolism in as little as five minutes after they have been rehydrated.
The resemblance between mosses and lichens is limited to the characteristics just mentioned. Mosses are very primitive green plants that use photosynthesis to obtain food, while lichens are an association between fungi and a few green algae or bacterium cells. These cells provide nourishment for the fungi through photosynthesis and, in exchange, they gain a moist environment that is rich in essential minerals.