The forests of Pakistan reflect great physiographic, climatic and edaphic contrasts in the country. Pakistan is an oblong stretch of land between the Arabian sea and Karakoram mountains, lying diagonally between 24° N and 37° N latitudes and 61° E and 75° E longitudes, and covering an area of 87.98 million hectares. Topographically, the country has a continuous massive mountainous tract in the north, the west and south-west and a large fertile plain, the Indus plain. The northern mountain system, comprising the Karakoram, the great Himalayas, and the Hindu-Kush, has enormous mass of snow and glaciers and 100 peaks of over 5,400 m. in elevation. K-2 (8,563 m.) is the second highest peak in the world. The mountain system occupies one third of this part of the country. The western mountain ranges, not so high as in the north, comprise the Sufed Koh and the Sulaiman while the south-western ranges forming a high, dry and cold Balochistan plateau. Characteristically, the mountain slopes are steep, even precipitous, making fragile watershed areas and associated forest vegetation extremely important from hydrological point of view. The valleys are narrow. The mountains are continuously undergoing natural process of erosion. The nature of climate with high intensity rainfall in summer and of soil in the northern regions render these mountains prone to landslides.
The Indus plain consists of two features; the alluvial plain and sand-dunal deserts. The country is drained by five rivers; namely, Indus, Jhelum, Chenab, Ravi and Sutlej. Of these Indus arising in snow covered northern mountain ranges flows towards south through the Punjab and Sindh plains into a wide delta before entering Arabian sea. Other rivers join it on the way, together feeding one of the largest irrigation systems in the world. The great river system of Indus in Pakistan derives a part of their water supply from sources which lie in the highlands beyond the Himalayas and the western mountains, and part from countless valleys which lie hidden within the mountain folds. Much of the silt of the alluvial plain is from natural geological erosion of mountains in the north brought down by rivers. Thal desert lies between the rivers Indus and Jhelum, while Cholistan and Thar deserts occur on the south-east of the country.
A great variety of parent rock types occur in Pakistan, which exert considerable influence on the properties of the soil. The rocks found in Pakistan can be classified into three major groups, viz. the igneous rocks, the sedimentary rocks and the metamorphic rocks. In the Himalayan regions, the common rock types are metamorphic which are gneisses, schists, slates and phyllites with some quartzite and marble. In the northern part of Indus plain, between Sargodha and Shahkot small outcrops of phyllites and quartzites occur. Granite, syenite, diorite, gabbro, dolerite and peridotite are more common types of igneous rocks, which occur in Dir, Swat, Chitral, Gilgit, Zhob, Chagai, Las Bela and Nagarparker.
