Map Key
Water
Forest
Mountains
Q2. Observe the given map and write the correct directions,
1.
Forest Gis
of the lake
The lake is
of Forest
of Forest v
There are mountains with no forest to
iv
of the lake.
The treasure is
of Forest R then
Pirates in the East will travel to
to reach to treasure.
Answers
Answer:
By contrast, mountains at temperate latitudes have strongly marked seasons. Above the tree line during the summer season, temperatures high enough for plant growth occur for only about 100 days, but this period may be virtually frost-free even at night. During the long winter, however, temperatures may remain below freezing day and night. Snow accumulation and the phenomena this type of precipitation may cause, such as avalanching, are important ecological factors in temperate but not tropical mountain regions.
Microclimate variations are also important in mountain regions, with different aspects of steep slopes exhibiting contrasting conditions due to variations in precipitation and solar energy receipt. In temperate regions mountain slopes facing the Equator—southward in the Northern Hemisphere and northward in the Southern Hemisphere—are significantly warmer than opposite slopes. This can directly and indirectly influence the vegetation; the length of time snow remains on the ground into spring affects when vegetation will emerge, and this in turn affects the land’s utility for grazing. Even in the tropics, aspect-related climate and vegetation contrasts occur, in spite of the midday vertical position of the sun. In New Guinea, for example, slopes facing east are warmer and drier and support certain plants at higher altitudes than slopes facing west, because the prevailing pattern of clear, sunny mornings and cloudy afternoons affects the amount of solar energy received by these contrasting aspects.
Mountain soils are usually shallow at higher altitudes, partly because the soil has been scraped off by the ice caps that formed on most high mountains throughout the world during the last glacial interval that ended about 10,000 years ago. Soils are generally poor in nutrients important to plants, especially nitrogen. Rapid erosion of loose materials is also common and is exacerbated by frost heaving, steep slopes, and, in temperate regions, substantial runoff of meltwater in spring. Soil is virtually absent on rocky peaks and ridges. However, because of the cool, wet climate, many mountain areas accumulate peat, which creates local deep, wet, acidic soils. In volcanic regions tephra (erupted ash) may also contribute to soil depth and fertility.
Considering the wide geographic extent of mountains and their resultant geologic and climatic variability, it is remarkable that they exhibit such a clear overall pattern in vegetation. The major structural feature of vegetation on mountains in all regions—except in very dry or very cold places—is tree line. (This characteristic is sometimes called timberline or forest limit, although strictly speaking the former term refers to the uppermost reaches that commercial-size timber trees attain and the latter term refers to a closed forest.) Above a critical level, which may vary between slopes on the same mountain and which is much higher on mountains at lower latitude, the climate becomes too harsh to permit tree growth; beyond that level grows alpine vegetation, dominated by herbaceous plants, such as grasses and forbs, or by low shrubs.
In general, the altitude at which the tree line occurs is determined by that at which the mean temperature in the warmest month approximates 10 °C (50 °F), provided moisture is not a limiting factor. This is not precisely the case under all circumstances, however; for example, in some tropical regions that have a yearlong growing season, forests can grow in conditions slightly cooler than this. Nevertheless, the value holds true in most regions, especially in the temperate zones. It reflects a fundamental requirement for a sufficient level of photosynthesis to occur to support the growth of tree trunks.
A relatively narrow belt of intermediate or mixed vegetation—the subalpine—usually exists between the forests below and the alpine vegetation above. In the subalpine of temperate mountains, stunted, usually infertile individuals of various tree species survive, despite blasts of windblown snow, frost damage, and desiccation. These deformed shrub-size trees are called krummholz.