Agro-ecological zones of Punjab, Pakistan

Agriculture, the largest sector of Pakistan’s economy, provides employment to 42.3 percent of the country’s labor force and contributes 23.3 percent to gross domestic product (GDP). However, that contribution has been decreasing continuously over the last two decades and sustainable enhancement of agricultural productivity has become the most important recent challenge. The rapidly growing population puts enormous pressure on natural resources; therefore, developing more efficient and sustainable agricultural systems to feed future generations is urgent.
For the last two decades, there has been no improvement in the yield of major crops: this may be due to factors including climate variability, cultivation of crops in areas that are not suitable for those crops (e.g. planting rice in an area more suitable for cotton), declining water availability, gradual changes in soil nutrient status and a lack of true-to-type cultivars. Moreover, agriculture has been dominated by five crops: wheat, rice, sugarcane, maize, andcotton. The narrow choice of crops is due mainly to a lack of understanding about the scope for more crops and a misallocation of resources. As well, the country has been unable to take advantage of the diversity of climate and land geographies, and consequently, it has become a net importer of otherwise locally cultivable crops such as fruits, vegetables, pulses and oilseeds, among others. This also means the country spends enormous amounts of foreign exchange to import edible oil, pulses, and seeds of many agricultural crops. There is a need to diversify and add more crops to existing cropping systems to achieve sustainability and diversification. The disadvantages and limitations associated with the expansion of cropland make it critically important to know where and how to increase crop yield on existing cropland area. An assessment of the physical and biological potential of natural resources that leads to the delineation of agro-ecological zones (AEZ) specific to crops presents a useful preliminary evaluation of this potential and ensures that representation is maintained at an appropriate biogeographic scale for regional sustainable development planning.