PAKISTAN IS an agricultural country. Contribution of agriculture sector in the GDP is about 21 per cent. It provides employment to 45 per cent of countrys labour force and is source of livelihood for 60 per cent of the rural population. It has a vital role in ensuring food security, generating overall economic growth, and reducing poverty. Our population is increasing very quickly, there is a lot of population pressure on the agriculture sector. To feed this high population, we are trying to enhance the agriculture productivity on the expense of land, water, labour, capital, climate and other resources ignoring the recommendations for good agricultural practices. Industrialization and urbanization has further aggravated the problem by reducing the area of production and polluting the land, water and environment, which is a direct threat to our agricultural productivity.
With the unbalanced use of our resources, we have created many problems such as loss of fertile land, water logging, soil salinity, erosion, pollution of above ground and underground water, habitat destruction etc. We are wasting our water resources, which are decreasing rapidly. About 75 per cent area of Pakistan is dependent on irrigation water. Our mismanagement of resources is a permanent cause of the higher levels of CO2 emissions and temperature increase leading to climate change with extreme events, which are destructive to our resources and agriculture productivity, which may cause the food security issues to rise up.
The food security is a global problem and especially for Pakistan, it is a great challenge. About 30 per cent of our population is living below the poverty line, and our farmer is also very poor with small land holdings. The high prices of inputs (fuel, seed, fertilizers, pesticides, herbicides, machinery and electricity, etc) have added much to the anxiety of the farmers. Farmers are living a subsistent life. Our average crop yields are much lower than other countries despite have lot of potential. Despite great recent progress, hunger and poverty remain widespread and agriculturally driven environmental damage is widely prevalent.
The idea of agricultural sustainability centers on the need to develop technologies and practices that do not have adverse effects on environmental goods and services, and that lead to improvements in productivity per unit area and profitability. Resource Conserving Technology (RCT) is a broad term that refers to any management approach or technology that increases factor productivity including land, labor, capital and inputs.
To arrest all such problems some of these technologies are briefly described here as;
Bed planting of crops
It is sowing of crops on the raised leveled surface. Crop is sown on beds in lines Size of bed and furrow depth depends on the type of crop and soil. Bed planter is used for making beds and/or sowing seeds. Using either dry or wet sowing method crop can be sown. Irrigation is applied in the furrows. For the sowing of wheat, University of Agriculture Faisalabad has developed a university bed planter machine. It makes two beds and three furrows in the same operation; bed width is 2 feet with four rows of wheat sowing on it, and furrow width is 1 foot.
The first row of wheat on bed is sown 3 inches away from either side of furrow, and 2nd row is sown 5 inches away from first line from either side; between these two lines there is a buffer zone with width of 8 inches for the accumulation of any salt. In this planting geometry of crop, plant population is not reduced in any way. This technology saves 40-50 per cent water, reduces the seed rate upto 10 per cent, better weed control and 20 per cent increase in the yield of the crop has been achieved. Similarly other crops can also be grown successfully on beds such as cotton etc.
Wheat residue management
After combine harvesting wheat, wheat stalks are a problem. To manage these residues Prof. Dr Ehsanullah (department of agronomy, university of agriculture Faisalabad) has developed a technology of sowing of Sesbania crop in the wheat. Presoaked seed (10-12 hours) @ 10 kg/acre is broadcasted in the standing wheat after last irrigation in the end of March or in start of April. After one month almost, wheat crop is harvested. Sesbania plants height is much smaller than wheat and escapes from combine harvester. After second irrigation to sesbania it is buried down in the soil along with wheat stalks. To accelerate the process of decomposition, half bag urea per acre can be added. This technology improves the soil health, manages wheat residues, reduces the fertilizer requirements to half and improves next crop yield.
Laser land leveling
It is a process of smoothing the land surface (± 2 cm) from its average elevation by using laser-equipped drag buckets, soil movers which are equipped with global positioning systems (GPS) and/or laser-guided instrumentation. To level the land, soil can be moved either by cutting or filling to create the desired slope/level. This technology gives uniform soil moisture distribution, better water application and distribution, good germination, enhanced input use efficiency, reduces weed, pest, and disease problems, reduced consumption of seeds, fertilizers, chemicals and fuel and improved yields. It may have cost and expertise constraints.
Direct seeding of Rice
It is a cost effective technology for the seeding of rice crop. The dry seed is drilled into the non-puddled soils with proper land leveling and weed control measures. Sowing of seeds at a depth of 2-3 cm is done with the help of zero till, minimum till or bed drilling machine after ploughing and leveling the field at @ 20-25kg/ha, fine and Basmati varieties will need much less seed rate. The seed is then covered with the thin layer of soil to aid in proper germination and to avoid the birds damage. Soil moisture in soil should be sufficient for better germination. The sowing of crop starts from end of May to start of June. The problem of weeds is tackled by application of pre-emergence herbicides (Glyphosate @ 0.5 per cent, 2 days before sowing) or by stale seedbed method. Next weeding can be done manually. This technology saves water by 35-40 per cent, avoids soil degradation and plow-pan formation, saves labor, energy, fuel, seeds, and gives 10 per cent higher yields with 10-15 days early maturation of crop.
Relay cropping of wheat
Relay cropping consists of inter-seeding the second crop into the first crop well before it is harvested. It is a form of intercropping in which both crops enjoy a short-term association; first crop is at its maturity and second crop is at its initial stage. Wheat is important crop for Pakistan. Due to late maturing varieties of cotton, sowing of wheat goes upto December and January. It is experimentally proved that after November 15 the yield of wheat is reduced @ 10-15 kg/acre/day. And with the introduction of Bt-cotton, about 7-10 per cent area under wheat has been reduced. So both these problems are direct threat to our wheat production and self-sufficiency. Relay cropping of wheat into cotton facilitates timely sowing of wheat, gives extra cotton pickings, saves the land preparation and labor charges, improves soil health and increases yields. It is economically and environmentally viable technology.
Zero tillage is one of a set of strategies aimed to enhance and sustain farm production by conserving and improving soil, water and biological resources. Essentially, it maintains a permanent or semi-permanent organic soil cover (e.g. a growing crop or dead mulch) that protects the soil from sun, rain and wind and allows soil micro-organisms and fauna to take on the task of “tilling” and soil nutrient balancing – natural processes disturbed by mechanical tillage systems. For example, there was a lot of problem of rice stubbles for the sowing of wheat, farmers were burning the residues destroying soil or managing it by disc plough or rotavator increasing cost of production. To address this issue; new technology of Turbo seeder has been introduced. It cuts and churns the stubbles and places it between the rows of seed drilled into the soil by inverted T shaped openers. There is no problem of operation or germination as observed in Zone disk tiller and Happy seeder. It decreases cost of production; improves soil health, saves water, labor and energy.
Widespread appreciation of the “global water crisis” recognizes that scarcity of clean water is affecting food production and conservation of ecosystems. By 2025 it is predicted that most developing countries will face either physical or economic water scarcity. So we have to go for efficient irrigation methods. Drip irrigation is one of them. It irrigates the plants drop by drop on the soil surface or directly into the root zone with the help of network of pump, valves, pipes, tubing, and emitters. It reduces evaporation, controls weeds, increase water and fertilizer use efficiency, saves water and fertilizer and increase yields.
It is a farming management concept based on observing and responding to intra-field variations with the goal of optimizing returns on inputs while preserving resources. It relies on new technologies like satellite imagery, information technology, and geospatial tools. GPS, GIS and Remote sensing satellites can track the soil variability, can assess the nutritional status of the soil, disease prevalence and can predict the yields. These technologies can reduce the input rates, decrease cost of production, increase yields and can reduce the environmental concerns.
Solar water pumps
With the current energy crisis scenario all over the world, and especially for Pakistan it is need of the day to utilize renewable energy sources for power generation to use for different purposes. Solar water pumps get solar energy from the sun and convert it into electricity by which water pumps can run for pumping of water for irrigation purposes. It is economical and environmental friendly technology.
Biogas is a flammable gas produced from renewable resources that can be used in many applications as an alternative to fossil fuel-based natural gas. A biogas plant is an anaerobic digester of organic material for the purposes of treating waste and concurrently generating biogas fuel. The feedstock of this plant is the animal dung, plant material, grease food wastes etc. Biogas converts this farm waste to biogas which can be used for home cooking purpose, lightning and for pumping water for irrigation.
The authors are associated with Agro-biology Lab, Department of Agronomy, University of Agriculture, Faisalabad.