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Many plants can be damaged or killed by freezing temperatures or frost. This varies with the type of plant, the tissue exposed, and how low temperatures get; a "light frost" of −2 to 0 °C (28 to 32 °F) damages fewer types of plants than a "hard frost" below −2 °C (28 °F). [9] [10]
Hardiness of plants is defined by their native extent's geographic location: longitude, latitude and elevation. These attributes are often simplified to a hardiness zone. In temperate latitudes, the term most often describes resistance to cold, or "cold-hardiness", and is generally measured by the lowest temperature a plant can withstand.
Arctic vegetation is largely controlled by the mean temperature in July, the warmest month. Arctic vegetation occurs in the tundra climate, where trees cannot grow.Tundra climate has two boundaries: the snow line, where permanent year-round snow and ice are on the ground, and the tree line, where the climate becomes warm enough for trees to grow. [7]
Certain frost-susceptible soils expand or heave upon freezing as a result of water migrating via capillary action to grow ice lenses near the freezing front. [2] This same phenomenon occurs within pore spaces of rocks. The ice accumulations grow larger as they attract liquid water from the surrounding pores.
Types of frost flowers include needle ice, frost pillars, or frost columns, extruded from pores in the soil, and ice ribbons, rabbit frost, or rabbit ice, extruded from linear fissures in plant stems. [1] The term "ice flower" is also used as synonym for ice ribbons, but it may be used to describe the unrelated phenomenon of window frost as well.
Photograph taken 21 March 2010 in Norwich, Vermont. Frost heaving (or a frost heave) is an upwards swelling of soil during freezing conditions caused by an increasing presence of ice as it grows towards the surface, upwards from the depth in the soil where freezing temperatures have penetrated into the soil (the freezing front or freezing boundary).
Permafrost temperature profile. Permafrost occupies the middle zone, with the active layer above it, while geothermal activity keeps the lowest layer above freezing. The vertical 0 °C or 32 °F line denotes the average annual temperature that is crucial for the upper and lower limit of the permafrost zone, while the red lines represent seasonal temperature changes and seasonal temperature ...
The loss of frost resistance occurs after warming. Rapid temperature fluctuations during winter deharden trees and increase the risk of spring damage. [5] Species that bloom first even before the leaves develop like apricots or peaches, are particularly vulnerable to damage. The reproductive organs, due to their abundant hydration, are easily ...