A forest referred to as a wood or the woods in an area with a high density of trees.
The forestry sector of Pakistan is a main source of lumber, paper, fuelwood, medicine as well as food and provide ecotourism and wildlife conservation purposes.
Overall Pakistan forest resources are limited, covering only 2.5percent of total land area, which is far below the standard of 25%,Less than five per cent of the country`s total area is under forests forest cover which is very poor as compared with other Asian countries. For example, in India, Japan, Sri-Lanka, Philippines, Korea, Bhutan and Brunei, natural forest area is 24.2, 36.4, 42.1, 43.6, 49.8, 50.4 and 90.4 per cent respectively of the total land area. Contrary to this, total forest area of Pakistan is around four million hectares including 0.51, 1.33, 0.84 and 1.36 million hectares in Punjab, NWFP, Sindh and Balochistan, respectively. However, forests of Pakistan are very rich in terms of biodiversity and present a unique blend of tree, shrub, grass and animal species, living across various ecological (climatic) zones. Most of the natural forest resources of Pakistan are concentrated in the mountainous regions of the north covering Himalaya, Hindukush and Karakoram ranges, where more than 60% of the country natural forest resources are found. The rest of forestry resource is distributed among the south-western mountains of Baluchistan, plains of Punjab and Sindh and the coastal areas of Arabian Sea in the south.
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| Forest covers distribution in Pakistan |
Alpine forests of Pakistan are found at very high elevations in the mountainous regions of Himalaya, Karakoram and Hidukush. These forests are subdivided into Sub Alpine forests, Alpine scrub and Alpine pastures. The Sub Alpine forests grow to the tree limit and due to harsh climatic conditions tree density is low. Alpine scrubs include shrub 150 m or more above the sub-alpine forests. Alpine pastures are situated above the tree line of 4000 meters, where growing season is very short and vegetation mainly consists of perennial, herbaceous plants. These high altitude pastures are found mostly in the northern districts of Gilgit, Diamer, Chitral and Skardu.
Temperate forests of Pakistan are sub-divided into moist and dry temperate, depending on the rainfall. In moist temperate zone high summer rainfall occurs where mountain masses stand exposed to the moist southwest winds. Moist temperate forests of Pakistan are concentrated in the northern districts of Muree, Kaghan valley, Kashmir region, and Swat Valley etc. On the other hand Dry temperate forests grow at the same altitude, as the moist temperate, but receive little of no summer rains.These forests are mostly found in the northern districts of Dir, Chitral, Kohistan, Diamer and Gilgit etc.
Sub-tropical forests are found in the lower reaches of Himalya, Hindukush and Sulaiman Ranges between 600-1700 m above sea level. These forests are subdivided into sub tropical broad-leaved forest and sub tropical pine forests. Broad leaved forests grow in the lower most reaches between 600-1000 m, and consists of drought resistant species. These sub tropical broad leaved forests cover fairly large area of about 1,191,000 ha. On the other hand Sub-tropical pine forests are found at little higher altitude1000-1700 m, meeting the temperate forests at the upper end.Chir pine is the major specie found.
Dry Tropical Forests fairly large areas of Pakistan fall under the dry tropical zone consisting of Indus plains in Punjab and Sindh and low hills in southern and western Balochistan. The climatic conditions varies from semi-arid (250-750 mm rainfall) to arid (<250 mm rainfall). The summer temperature in zone goes up to as high as 50oC. Dry Tropical Forests of Pakistan can be categorized into two group’s i.e. tropical thorn forests and tropical dry deciduous forests. Tropical thorn forests mainly consist of low and scanty trees and shrubs of thorny species. On the other hand Tropical dry deciduous forests consist of almost entirely of deciduous species. These forests do not occur extensively in Pakistan but are limited to the Rawalpindi foothills.
Main forest types are:
The coniferous forests occur from 1,000 to 4,000 m altitudes. Chitral, Swat, ranges of the Himalayas and Hindu Kush and Abbottabad districts of Pakhtunkhwa, Northern Areas and Islamabad district of the Punjab are the main areas covered with coniferous forests. Silver fir, deodar, blue pine, chir pine are the most common varieties. The Coniferous forests also occur in Balochistan hills. Chilghoza pine and juniper are the two most common species of Balochistan.
They supply people with lumber, fuel wood, fodder and medicinal plants.
The riverine forests mostly grow on the banks and dry bed of the River Indus in the flood plains of Sindh and Punjab. Their existence depends on annual flooding in the Indus basin. These forests are of high economic value yielding timber, fuel wood and latex. These forests also form a protective line barrier between river and the embankments against floods.
The mangrove forests are located in the Indus River Delta.Mangrove forests are the natural shield for heightened waves, cyclone and tsunami. Their roots and stems absorb shocks of the tides and transform them to a gentle stage. Mangrove forests also provide the breeding ground for fish, birds and livelihood to fishermen. Different organizations using remote sensing data for monitoring the health of newly planted mangroves forests in the coastal region. Satellite images can show the distribution of mangrove forests along coast of Pakistan and can depict mangrove forest in Indus delta
Irrigated forest is spread over the plains of Punjab and Sindh.The canal water is used for development and growth of this plantation.A typical example is Chhanga Manga irrigated forest plantation.
The irrigated plantations were first developed in 1866 at Changa Manga in Lahore. Today they occupy about 226,000 ha. Sheesham, mulberry and species of Populus are the common tree species grown in the irrigated plantations.The Irrigated forests were raised to meet demand for fuel wood.
Deforestation
Pakistan has few forests to begin with, and they’re vanishing fast. The country has lost a quarter of its natural forest cover over the past two decades and is currently experiencing a deforestation rate of 2.1 percent a year. Pakistan is having the world's second highest rate of deforestation.
The causes of the deforestation are multiple i.e.increase in temperature and decrease in rainfall, illegal cutting and clearing of forested lands for agriculture and for expanding urban areas are only the main ones.
Effects of deforestation are erosion of soil, disruption of the water cycle, flooding and drought, climate change.
A province-wise breakdown of forest land converted to other uses shows that Punjab tops the list with conversion of 99,711 acres, followed by Sindh with 27,874 acres, Balochistan with 13,693 acres, Khyber Pakhtunkhwa with 9,692 acres, and Azad Jammu and Kashmir with only 577 acres. This way the forest land conversion becomes 151,548 acres.
The highest rate of deforestation has been found in the Indus delta mangroves, which has depleted at a rate of around 2.3 percent, while the coniferous forest depleted at 1.99 percent and ravine forests at 0.23 percent.
Over 4.242 million hectares in the country were forest land in 1992. However, it declined to 3.44 million hectares by 2001.
Between 1990 and 2010, Pakistan lost an average of 42,000 ha or 1.66% per year. In total, between 1990 and 2010, Pakistan lost 33.2% of its forest cover or around 840,000 ha.
TOTAL FOREST COVER (1000 ha)
1990 2000 2005 2010
2527 2116 1902 1687
ANNUAL CHANGE RATE (percent)
1990-2000 2000-2005 2005-2010
-1.76 -2.11 -2.37
Negative number represents deforestation
Afforestation of Sindh coastline was made to save Thatta and its adjoining areas from destruction caused by sea intrusion, the provincial government has decided to plant trees on the coastline of the district. Sea intrusion and destruction of mangrove forests has exposed these coastline districts to other disasters such as cyclones and tsunamis. Mangroves, coconuts and other trees should be planted in these areas as they can survive the damp and salty climate of the ocean.
REFERENCES
http://www.wildlifeofpakistan.com/IntroductiontoPakistan/forestsofPakistan.htm
http://www.suparco.gov.pk/downloadables/10-Role-of-Satellite-Remote-Sensing.pdf
This article was compiled by:
Arsheen Nasir
Department of Space Sciences,
Uinversity of the Punjab,
Quaid-e-Azam campus,Lahore
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