Sustainable soil management is defined as soil services like supportive provisioning, regulating, and cultural amenities are regulated and increased. Considerably without harming the soil fauna and flora. The supportive facilities consist of primary production, nutrient cycling & soil development. They contain the supply of feed, food, fiber, habitat, wood, raw earth surface material, stability and genetics properties.
The regulating service area provide the maintenance of water source & quality, carbon sequestration, climate change effects, control mechanism of soil erosion and floods. The cultural services mean the appealing and cultural profits derived from soil practices. These different soil services are managed differently according to agro-ecological zones. For achieve goals of sustainable agriculture.
Agriculture is the most important business in Pakistan. It shares 19.5% of the Gross Domestic Production and engages 42.3% employment. Providing raw material for agriculture industry. These raw material after processing and value addition give higher output. Agriculture plays an important role in national development, food security and poverty reduction.
The urban area of Pakistan demands high value perishable products such as fruits and vegetables. To increase the yield of crops efforts are done. Enhancing of agriculture business profit by adopting innovation in value added products, processing industry and supply chain management.
Climate change and soil:
The climate of Pakistan is arid to semiarid. In result, the country faces problems ( i.e. high temperature, low rainfall and lower soil fertility). By adoption of innovative techniques in farming and rely on farm inputs and renewable local resources. Which reduces losses in agriculture. The climate change also effects on soil temperature precipitation and temperature. The soil is shallow in cold areas because of less farming. In lowland areas organic rich soils are common due to chemical and biological decomposition.
In warm areas mineral alteration & leaching processes are common. So such conditions organic matter decomposition and chemical weatherizing processes take place at a faster rate. The innovative technologies include sustainable systems in agriculture that utilizes resources. That in a way, will not harm the environment. Becoming appropriate for economic and social acceptance.
Role of soil fertility in sustainable agriculture
A fertile soil is not a productive soil. Through sustainable agriculture practices fertile soil is converted into productive land. In sustainable agriculture, to meet present food needs. Also without degradation of basic resources to fulfill the future demand. By following these rules of sustainable agriculture, soil fertility can be improved. It will enhance the quality and yield of crops. Plant nutrition is based on crop’s need, soil characteristics and weather conditions. Soil texture is also refined by the addition of plant wastes and animal manures.
Minerals in soil
The incorporation of green manures maintains soil fertility. Furthermore, there is availability of nutrients at critical stages of crops. Soil fertility is ability of a soil to supply soil nutrients necessary for plant growth and development. To meet the requirements of plants , it is focused on balanced supply of all essential nutrients. Phosphorus is deficient in Pakistani soils and it is major element required by plants.
It can easily make bonds with soil particles and become unavailable to the plants. Soil fertility survey pointed out phosphorus is second deficient major nutrient after nitrogen in Pakistani soils. Pakistani soils are eighty to ninety percent deficient in phosphorus availability like mostly arid regions of the world. Arid region soils are calcareous and alkaline in nature and fixed with phosphorus elements.
Fertillizers
To minimize this problem exogenous application of phosphorus fertilizer is expensive and efficiency of this practice is just 10%. The crops yield is stagnant in Pakistan due to low organic matter and fertilizer use efficiency. The reasons of low fertilizer use efficiency are physical and chemical characteristics of soils. Moreover, the quality of chemical fertilizer, application methods, unavailability at required time, unbalanced use and high cost of fertilizers are also a reason for it.
Plants absorb nutrients from soil in dissolved solution form. The ratio of soil particles (solids, water & air) is important for plants oxygenation and irrigation availability. Fertilizers deficiencies in plants will improve by applying organic and inorganic fertilizers recommended by plant’s nutritionist. Sandy soil provides less water for plant growth during hot periods due to low water table. High water available in soil surface can lead to anoxic problem and it is toxic for plants. Only hydrophytes’ plants can bear it. So integrated nutrient management is necessary for maintaining sustainability of soil.
Sustainable management of soil for improving agriculture productivity
For present and upcoming generations the maintenance of soil productivity and fulfilling food requirements is the subject of sustainable management of soil.
Inappropriate use of chemicals, doses rate and time application are disturbing soil and plant relation. Maintaining productivity of soil the physical, biological and chemical practices that involves in ordinary soil profile have considerable importance.
It is necessary to maintain the fertilizers application methods, rate, time and doses as per directions of agriculture officers. Crop rotation can reduce the chances of insects pest attacks and diseases.
Hence, it also improves soil fertility and permits for a well-functioning food web. In crop rotation different crops have different root lengths results lower bulk density of soil. After harvesting of crops do not burn trashes but cooperate in the soil to improve organic matter.
Addition of organic waste in soil maintains activity of microorganisms. The minimum tillage and no tillage improves water use efficiency and protect soil creatures. Thus, it also reduces soil compaction and farmers input cost.
Problems and risk
Specifically, due to high tillage organic matter decomposition rate it release more carbon dioxide and GHG (greenhouse gas) into environment. Furthermore, no till farming system is environment friendly because of sequestration of carbon in the soil. Additionally, the no till system can reduce global hazards and maintain sustainability of the soil. Therefore, the major causes of erosion are deforestation and lower grass cover.
Tree plantation and green ground covers lower the risks of erosion and improve climate. Proper irrigation managements and water use efficiency reduces soil salinity. The acidic soils are reclaiming by using balance of acidifying fertilizers and organic waste.
For achieving all targets of sustainable soil management and agriculture. Since farmers are important component of farming community, it is compulsory to train them at local level. Moreover, farmers education and trainings are most important. To enhance agriculture gross domestic production in economy of country.
This article is jointly authored by Muqarrab Ali and Iqra Ghafoor at Department of Agronomy, Muhammad Nawaz Shareef University of Agriculture Multan.