Pakistan being one of the eight member countries of the International Centre for Integrated Mountain Development (ICIMOD), is actively engaged in its macro level land cover assessment in collaboration with UNEP Environment Assessment Programme for Asia and the Pacific (UNEP/EAP.AP). With the limited resources and time frame, however, it will not be possible to bring about a detailed micro-level assessment of the land cover. Still, it has been endeavored to add as many parameters to the report as possible. Some of the data included in the report is as old as 10 years. However, this data could be used as a baseline for a comprehensive report to be prepared in the future. That would greatly facilitate the comparison between the old and the new data and might be helpful in ascertaining the physical changes occurring particularly in the land use pattern and look for possible corrective measures if the situation so warranted.

Location and Physical Characteristics of Pakistan GREENRY

Pakistan has a great variety of landscapes with a diversified relief. It has all the majestic high mountain ranges of the sub-Continental north: the Himalayas, the

Karakorams and the Hindu Kush. The vast and rich irrigated plains of the Indus Basin covering vast tracts of the Panjab and Sindh, the stark deserts of Cholistan (Punjab!) and Thar (Sindh!), the inter-montane valleys of NWFP (North West Frontier Province) and the awe-inspiring rugged plateaus of Balochistan and the meeting point of the Himalayas, the Hindu Kush, and the Karakorams in the Northern areas are some of the most varied features of the country’s landscape.

Geographically, Pakistan lies between 24o and 37o N latitude and 61o and 75o E longitude. It is bordered by China in the north, Arabian Sea in the south, Iran in the west, Afghanistan in the north-west and India in the east (Fig. 1). It is a federation of four provinces: NWFP, Panjab, Sindh and Balochistan with its capital at Islamabad. The land area of Pakistan is about 796,000 sq. km and an estimated population of 134 million (June 1996), having a population density of 168 persons per sq. km.

Of the 79.6 million hectares land area, only about 22 million hectares (23%) are available for cultivation: 18 million ha irrigated and 4 million ha rain-fed. Forests, both natural and man-made, cover about 4% of its land area.

The CLIMATE

The climate of Pakistan varies with altitude, which in turn affects the type of vegetation. It has some of the world’s highest cold areas that occur above 5,175 masl in the Himalayas and the hottest low areas in the Indus Plains with many intermediate ecological zones.

Pakistan has nine major Ecological Zones with the main ecological determinants as Arid and Semi-Arid conditions. These conditions prevail over most part of the Indus Plains and the Balochistan Plateau. The Humid conditions exist over the hills and mountains in the north. In the Arid and Semi-Arid areas, most parts are bare of vegetation. At riverbanks and deltas, Riverain and Mangrove forests have emerged. On humid hills and mountains, pines and coniferous forests occur that change with altitude. The Dry sub-Tropical forests dominate up to an altitude of 1,000 masl, the Coniferous forests from 1,000 to 4,000 m. Above tree line, Dwarf Alpine forests followed by the Alpine Pastures occur up to snow line.

Based on the above classification, the following seven forest types are recognized:

1. Alpine Forests
2. Coniferous Forests
3. Sub-Tropical Forests
4. Tropical Thorn Forests
5. Irrigated Plantations (artificial!)
6. Riverain Forests
7. Mangrove/Coastal Forests

The Alpine Forests occur in the northern districts of Chitral, Swat, Dir and Kohistan. Because of long severe winters, dwarfed and stunted trees of Silver Fir (Abies webbiana), Juniper (Juniperus spp.) take place.

The Coniferous Forests occur from 1,000 to 4,000 m altitudes. Swat, Dir, Malakand, Mansehra and Abbottabad districts of NWFP, and Rawalpindi districts of the Panjab are the main areas covered with coniferous forests. Fir (Abies spp.) and Spruce (Picea smithiana) occupy the highest altitudes, Deodar (Cedrus deodara) and Blue Pine (Pinus wallichiana), the intermediate heights, and Chir Pine (Pinus roxburghii), the lower areas. The Coniferous forests also occur in Balochistan hills. Chilghoza Pine (Pinus gerardiana) and Juniper (Juniperous macropoda) are the two most common species of Balochistan.

The sub-Tropical Dry Forests are found in the Attock, Rawalpindi, Jhelum and Gujrat districts of the Panjab, and in the Mansehra, Abbottabad, Mardan, Peshawar and Kohat districts of NWFP up to a height of 1,000 m. In Balochistan, they are confined to the Sulaiman mountains and other hilly areas. Dominant tree species are Phulai (Acacia modesta), Kau (Olea cuspidata) and Donoenia viscosa.

The Tropical Thorn Forests are dominated by Xerophytic Scrubs. They are most widespread in the Panjab plains. They also occupy small areas in southern Sindh and western Balochistan. Common species are Acacia spp., Salvadora oleodes, Prosopis cineraria, Capparis aphylla, etc.

The Irrigated Plantations were first developed in 1866 at Changa Manga (Panjab!). Today they occupy about 226,000 ha. Shisham (Dalbergia sissoo), Mulberry (Morus alba), Babul (Acacia nilotica), Eucalyptus and Populus spp. are the common tree species grown in the Irrigated Plantations.

The Riverain Forests grow in narrow belts along the banks of Indus and its tributaries. They are more commonly found in Sindh and to some extent in the Panjab. Babul (Acacia nilotica), Shisham (Dalbergia sissoo) and Tamarax dioica are the most common species. Prosopis cineraria, Tamarax spp. and Populus euphratica are some other species found in these Forests.

The Mangrove Forests are located in the Indus delta. However, lack of fresh water has resulted in their stunted growth. Avecennia officanilis is the main species. Ceriops and Rhizophoras are the other tree species but are fast disappearing because of human pressure.

Areas of Major land cover Transformations (Hot Spots)

As a consequence to deforestation and changing land use patterns, the most critically affected ecosystems of Pakistan are:

Juniper Forests of northern Balochistan, essentially categorized as Protected Forests, are heavily harvested for timber and fuelwood. The unrestricted grazing has further hampered the natural regeneration of trees.

Indus River Zone is the other such area where ecological changes have drastically affected the Riverain Forests as also the Coastal Mangrove Forests. Large tracts of riverain forests have been cleared for agriculture. The river Indus has been dammed and dyked and thus confined. The resulting drop in river level has left extensive areas of the riverain forests high and dry.

As a further consequence of the construction of upstream dams (in the northern parts) and barrages in the plains of the Panjab and Sindh, there has been considerable drop in the Indus water. This has caused reduction of fresh water flow in the delta (at the confluence of the Arabian Sea) resulting in increased salinity which in turn has damaged the mangrove forests and thus eliminated several tree species. The uncontrolled cutting of trees for firewood and fodder needs has further accelerated the reduction and degradation of swamp forests.

Posted By: Administrator Posted Date: 2019-04-09