Environment of Zambia

Zambia takes its name from the Zambezi River, which rises in the north-west corner of the country and forms its southern boundary. The landlocked country lies between latitudes 10o and 18o South and longitudes 22o and 33o East.
It’s neighbours are: Congo DR to the north and north west, Tanzania to the north east, Malawi to the East, Mozambique to the south east, Zimbabwe to the south, Botswana and Namibia to the South west and Angola to the West.
Zambia’s 752, 000 square kilometres makes it a large country about the size of France, the Netherlands, Belgium and Switzerland combined. It consists for the most part of a high plateau, with an average height of between 1060 and 1363 meters above sea level. (3500 and 4500 ft). Isolated mountain ridges rise to more than 6000 ft with an occasional peak above 7000 ft on the eastern border, called Nyika Plateau. Over most of the country the surface tends to be flat, broken by small hills, the result of countless ages of undisturbed erosion of the underlying crystalline rocks. These rocks contain the bulk of the country’s wealth in the form of minerals and the 90 mile long corridor known as the Copperbelt, along the north-western part of the country, is the mainstay of the economy.
The level of the land falls southward from the Congo DR / Zambezi divide in the north towards the Zambezi depression in the South. The plateau is broken by the huge valleys of the Upper Zambezi and its major tributaries, of which the Kafue and Luangwa rivers are the largest. One result of the plateau formation of Africa generally is the swift discharge of water towards the coast and the interruption of the rivers by waterfalls and rapids. This has made them of little value for transport over their length, but very suitable for hydroelectric schemes and white water rafting adventures.
With the exception of the Northern and Luapula provinces which are part of the Congo DR basin, Zambia lies on the watershed between the Congo DR and Zambezi River systems. The three great natural lakes of the country, Bangweulu, Mweru and the southern end of Lake Tanganyika are all in the north and are part of the headwaters of the Zaire River. Lake Tanganyika is the second deepest natural lake in the world.
Lake Bangweulu, which with its swamps covers an area of about 3800 square miles, is drained by the Luapula River. This river starts flowing south, then turns west and northwards to pass through Lake Mweru on its way to Congo DR.
Along the southern border of the country stretches Lake Kariba, the largest man made lake in Africa and the second largest in the world. It is about 280kms long and 40kms across at its widest point.
The Climate
The general height of the land gives Zambia a more pleasant climate than that experienced in most tropical countries. There are three seasons – cool and dry from May to August, hot and dry from September to November, warm and wet from December to April.
Only in the Valleys of the Zambezi and Luangwa is there excessive heat, particularly in October and, in the wet season, a high humidity.
In the warm wet season, frequent heavy showers and thunderstorms occur, followed by spells of bright sunshine. Plants grow profusely and rivers and streams fill up almost overnight.
During the cool dry season, night frosts may occur in places sheltered from the wind. The countryside dries up gradually and grass fires, fanned by high winds are a feature of this time of the year. In depressions, radiation occurs on cloudless nights.
Temperatures rise high during the hot, dry season but new leaves appear on the trees before the start of the rains and new grass brightens the countryside. The main growing period of woody vegetation is between August and November.
The Rainfall
While the rainfall pattern over the whole country is similar – between November and March, the amount of rain varies considerably.
The climate is affected most by the movement of the inter-tropical convergence zone, which is the meeting place of the sub-tropical high pressure areas of the northern and southern hemispheres. Over the sea, this zone approximates to the equator, and when the sun is overhead at the equator, heavy rains may fall in the equatorial regions of Africa. The zone moves southward with the apparent movement of the sun in the southern summer and brings rain to the greater part of Zambia.
In the north of the country rainfall is 1250mm/ (50 inches) or more a year, decreasing southwards to Lusaka where it is about 750mm/ 30 inches annually. South of Lusaka rainfall is dictated more by the east and Southeast trade winds, which have lost much of their humidity by the time they have reached so far inland. Rainfall in this area is between 500 and 75omm / 20 and 30 inches. In exceptional years the influence of the inter tropical zone is felt much farther to the south, resulting in excessive rain in the Southern Province and partial drought in the north.
Except for very rare falls in August, rainfall is confined to the wet season, which sometimes starts as early as October and finishes as early as March. At the height of the wet season it rains on seven or eight days out of ten.
Average temperatures are moderated by the height of the plateau. Maxima vary from 15oC to 27o C in the cool season with morning and evening temperatures as low as 6oC to 10oC and occasional frost on calm nights in valleys and hollows which are sheltered from the wind.
In the cool season the prevailing wind, dry south easterlies come from the southern hemisphere belt of high pressure. Invasions of cold air from the south-east bring cloudy to overcast conditions. During the hot season maximum temperatures may range from 27o C to 35o C.
The table below shows annual rainfall and representative maximum and minimum temperatures during the hottest and coldest months of the year respectively. It can be seen that annual temperature variation is greatest at Livingstone, the most southerly town, and the smallest at Mbala, the town nearest the equator.
Zambia’s vegetation is of the savanna type and over half the country is covered by trees, varying from the more open conditions in the drier south to tall dense woodlands in the north and north-west. These woodlands contain only hardwoods. The trees are bare for a brief period only and the spring leaves appear before the start of the rains. Grass fires spread rapidly in the dry season but new blades of grass soon push through the blackened earth.
Zambia’s climate makes possible the cultivation of a wide range of crops; maize, tobacco, cotton, rice, wheat and groundnuts. All kinds of vegetables can be grown, together with citrus fruit, bananas, pineapples, mangoes, avocados and even grapes. Lichis are also a high potential export crop. Tea and coffee are also grown successfully in fact the coffee produced is of a very high quality. Sugar cane is grown both by villagers and commercially.
Natural Resources
Apart from its abundant wildlife, rivers, and lakes, Zambia holds 6% of the worlds copper reserves and is the fourth largest copper producing nation in the world. Zambia is internationally recognised as a major producer of emeralds, aquamarines, amethyst and tourmalines and the quality of the gems are highly competitive with world markets.

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