A sustainability oriented technology and Soil health

Mohsin Tanveer, Shahbaz Atta Tung, Haseeb Zahid

Nature has sanctified us with biological entity and life is not possible without it. And that biological entity is SOIL. Soil is layer of upper earth crust and a source of mineral nutrients, containing a vast array of organic, inorganic nutrients and gases in different proportions. Plant takes up 16 elements from soil and makes its food. Unfortunately, we are not taking care of it and under the scenario of current agriculture problems; soil health is of burning issue right now. Agriculture is modified and transformed into industry and now the only aim of farmer is to get high yield even though he has to deteriorate its soil. Farmers have increased their cropping intensity in greed of more earning without taking into consideration of soil health. As a result, nutrient status of soil is diminishing rapidly day by day.

Although the nutrient requirement could be done with synthetic fertilizer application, but fertilizer prices and their quality is still a question. However, total avoidance of synthetic fertiliser is not possible, so there is need of sustainability oriented approach that reduces artificial fertilizer application and improves soil fitness. The basic concept behind adoption of that technology is just to increase organic matter in soil. Soil fertility depends on the availability of organic matter. This organic matter not only improves water holding capacity, nutrient retention capacity but also enhances microbial activity in soil by providing them food. It is primitive for better productivity that our soil should contain enough nutrients. Plant stores nutrient in grains, leaves, stem and roots. It is rule for successful and progressive farming that, after removing economical part of plant, remaining should be incorporated in soil.

Using combine harvesters, lot of wheat stubbles remained on soil and that is marvellous source of organic matter. Usually farmers burn these stubbles and putting stubbles on fire causes environmental issues and loss of nutrients and sometimes it takes shape of massive accidents. Burning also affects soil microbes and reduces soil health. Burning of stubbles is crime, then why does our farmer do this? The reason is, he does not have any idea how to get rid of that and what to do with that. Department of Agronomy, University of Agriculture Faisalabad has devised a system that not only improves soil health but also provide an additional source of income. Main benefit of this technology is that being leguminous crop and addition of organic matter in soil, fertiliser requirement dips to half amount and by burning, 80% nitrogen, 25% phosphorous and 21 % potassium is lost. On the other hand these nutrients can be returned back by putting them in soil. Dr. Ehsan Ullah and his team introduced three methods:

Sowing of Sesbania in standing wheat: Sesbania is leguminous crop that has potential to produce excess biomass in short time with low input requirement. It has capability to fix nitrogen in soil and increase nitrogen concentration in soil. At the end of March/ start of April and when last irrigation of wheat is done then broadcast sesbania at rate of 10 kg per acre in standing wheat. Soak the seed for 10-15 hours before surface steeping that increase germination speed. Then at harvesting time of Wheat, Sesbania grows up to height of 1 foot and at that time it is not ploughed in soil by using simple cultivator. At this stage, upper grown parts can be harvested and fed to animals as fodder. And below ground parts may be act as organic matter in soil. 2) Sowing of Sesbania after wheat harvesting: Sometimes, farmers do not able to sow seed, might be due to unavailability of seed. Then they can sow seed even after harvesting. Seeds may be sown by giving irrigation heavily after harvesting and broadcast primed seed in field. In this method, Sesbania get little height at time of land preparation for rice. But that little biomass of Sesbania improves sol health a lot.

Sowing at field capacity level of soil after wheat harvesting: In this method, seeds are broadcasted at field capacity level (optimum soil moisture level) of soil after harvest of wheat. Weeds may also be growing in this way that can be removed easily. Incorporate the Sesbania when, land preparation is required. Under all these methods, our aim is to introduce a leguminous crop and utilize nutrients and time between wheat harvesting and sowing of next crop. There are two methods, employed to incorporate them in soil. Through rotavator: Rotavator is best option for Sesbania incorporation. Give light irrigation to field, then at optimum moisture level, rotavate the field, in this way stubbles of wheat and Sesbania may be cut down and can be easily incorporated. By puddling method: At the core areas of rice belt, it is started raining and at that time Sesbannia may be deposited in soil in that standing water of rain. This method yield two benefits, firstly the rovator cut down plants in to small pieces which will start decomposing abruptly and secondly, there will be no need of land preparation further. Soil becomes soft and fertile after this method and that helps in transplanting of rice nursery.

Questions regarding the adoption of this method:

· Some farmers feel reluctant to spend money on purchasing Sesbania seed. They do not want to increase the expense but they do not know, if they use this technique, they will not only sustain their soil but also get high yield and price of Sesbania seed is very low.

· Some farmers ask how this will increase our yield. The answer is Sesbania is leguminous crop. It will fix environmental nitrogen in soil and boost up the availability of nitrogen in soil. This will reduce fertiliser requirement.

· Some farmers inquired about the feasibility of adoption of this method. This method is feasible under all agro-ecological zones and can be adapted at all kind of soil series.

Wheat: Planning for better yield (بہتر پیداوار کے لئے منصوبہ بندی: گندم)

The wheat is sown the world over on an area touching 220 million hectares producing 600 million tons with an average of 2700 kg. of grain per hectare.

The Main land China brings 30 million hectares the largest are in the world followed by Russian Federation, India, USA, Australia, Canada, Turkey and Pakistan.

As far as the highest yield is concerned, France produces 7200 kg per hectare. Who leads other countries because it has much longer growing season of winter wheat? It is rather more appropriate to compare our wheat grain yields with countries of similar climatic and eco-zones, like Mexico and Egypt. Their yields are much higher owing both genetic constitution of cultivars and environment provided to them to express their biological potential.

Since Mexico and Pakistan are located in analogous ecological zones therefore, introduction of Mexican varieties in the country in sixties verities in the country in sixties ushered an era of green revolution. But unfortunately the pace of development could not be maintained for long and we now lag much behind the Mexican yields, who have gone for ahead of us producing 3900 Kg. of wheat grain per hectare as compared to 2491 K. for us in the year 1999, the best season. According to FAO statistics for 1995, among spring wheat growing countries Egypt has fantastic yield by producing 5422 kg. of grain per hectare where as Indian Punjab producing 4090 kg. and even India leads us in average yield by producing 2559 kg. notwithstanding three times largest area as compared to ours.

In our country wheat is cultivated largely (80 per cent), in irrigated areas whereas, rest in rain-fed. The yield and production in latter part of the country is predominantly controlled by rains during growing season, which usually are erratic. Hence yields are much lower during season of low precipitation.

There are of course three kinds of wheat cultivars, the long duration, the medium and short duration varieties. The wheat yields usually start declining after 20th Nov sowing at the rate of 20 kg per day.

Hence efforts must be made to plant it at optimum time. In cotton areas the sticks are by and large used as fuel in domestic house hold. Big heaps of cotton sticks can be seen along the roadside and in villages.

There is a great need to educate growers as to how much yield is last due to burning of sticks. So as to restores the soil fertility at least 80 per cent sticks may be buried in soil. In order to enhance the decomposition half a bag of urea per acre may be incorporated in the soil after the stick burial.

In view of numerous benefits through the addition of organic matter from cotton sticks, may be made mandatory for each farmer. In case wheat sowing is delayed owing to late maturity of cotton, wheat may be sown in standing crop, if there is low or no incidence of weeds. However in rice tract wheat should be sown on proper time immediately after crop harvest. In rice zone a sizable area must be brought under this season legumes, the chickpeas and lentils. It is of course not so difficult to reap their yields up to 1000 kg per acre, which will bring more finances to the growers as compared to raising wheat.

Adequate quantity of nitrogen, phosphorus and potash may be applied to harvest maximum grain. If phosphorus is added adequately it will not only help to realize good harvest, the following crop of cotton shall utilize the remaining residual phosphorus, without adding more of this element to cotton.

In my opinion there are three main factors, which largely contribute towards low wheat yields, the optimum time of sowing, prevalence of high intensity of weeds, imbalance use of fertilizer. The low level of organic matter is also important for holding the yield. In irrigated areas the crop is generally sown either after the harvest of cotton or paddy.

In most of the cases it is customary that farmers neither add organic matter nor farmyard manure to maintain fertility, thus resulting in low yields. In order to sow wheat at optimum time the cotton breeders in collaboration with cotton agronomists must try to reduce the life span of cotton crop without hampering the yield and deteriorating the quality of lint. In this way not only have substantial saving on the management of cotton but also timely sowing of wheat to realize maximum yields. As far as weeds are concerned it is estimated that decline in wheat yield ranges from 15 to 40 per cent or even more in some cases, which is indeed a great loss towards food self-sufficiency.

As my experience goes tit is much worst in certain localities where it appears as if wheat is an unwarted and obnoxious plant. It is in fact a glaring negligence on the part of extension workers and the grower himself.

The extension workers with the help of farmers may try to delineate the areas of high infestation of "Dumbi Sitti" and wild oats.

The farmers in such areas may be advised to control them through agronomic practices or herbicide treatment or removing the weed plants just after earring because at that stage it is easy to differentiate between both the weed and wheat plants.

If these weeds are not controlled now they will spread like a wild fire in coming years in whole of wheat areas. Thee weeds have capability to produce large quantities of seed, which is always shed before wheat harvest. Henceforth infestation increases at an alarming pace. These two weeds along with "It Sit" can be used as biological warfare in agriculture. On the other hand in barani areas "Pohalli" is quite a common weed, which can be easily seen while travelling by air, road or rail after the harvest of wheat.

The abundance of this weed undoubtedly is a main factor for low yield in the area. The Pohalli remain green much after harvest of crop. At that time it is an appropriate time to launch a campaign to eradicate it by uprooting and burning. Two or three exercise will help to whip out the weed in barani areas. Henceforth this year may be declared a Pohalli eradication year. The road sides and sides of rail tracks may also be cleared of it.

The pace of yield increase per hectare during past twenty years has been awfully poor rather frustrating since 1980 to 01. The population growth however, over whelmed the increase in yield per unit area therefore; the enlarged demand of wheat consumption was met by bringing more area under crop.

Which certainly is not a good omen. But for how long increase in area under crop shall come to our rescue. This problem has to be tackled through serious and wise planning and execution.

First of all we shall have to get rid of non-technocrats from lowest level to highest in the ministry of food, agriculture and livestock and induct able selfless agricultural scientists but not the pseudo ones. More funds have to be infused for research and transfer of technology. At the same time we must motivate the general public to diversify the so-called dietary pattern, is greatly imbalanced, which required to be substituted by balanced through intake of nutritive food, so as to reduce unnecessary burden on wheat. Besides this we must substantially boost yield per unit area. Thus placing this area under oil seeds, vegetables, fruits, pulses, and flowers. Also considerable area may be brought under fodder to raise ore animals for milk and meat production. Last but not the least we ought to arrest population growth.

With the improvement in agronomic practices we must try to equate with Egyptian or across the Punjab wheat yields in less than three or at the most five years.

Storage facilities: There are many stored grain pests, which destroy a considerable quantity of produce while in store in villages. Efforts may be made to eliminate the losses. If these losses are controlled it is possible that we may not have to import food grains any longer.

Courtesy Daily Dawn, 10 December 2001

Sustainable agriculture and fertilizer practices in Pakistan

 

Mohammad Ali Khaskheli

Agriculture Officer Sanghar

Agriculture is the mainstay of Pakistan’s economy. It has a total area of 79.61 million hectare, and the total area used for crop production is only 22 million ha. Of which about 18 million ha (80 percent) are irrigated. Pakistan agriculture accounts for 24 percent of the growth domestic product (GDP), employs 48 percent of the labour force and contributes about 60 percent to export earnings.

Pakistan is a developing country with the world's sixth-largest population. The current population of Pakistan is about 160 million, which is growing at the rate of almost two percent annually. The major population of the country (67 percent) lives in rural areas and depends mainly on agriculture, and about 32 percent of the population lives below the poverty level. GDP growth continues to depend on crop performance.

The total food production in Pakistan is about 25 million tones in 2002/03 as compared to 10 million tones in 1970/71. However it is interesting to state that the consumption of fertilizer per hectare in Pakistan (133 kg approx.) is higher than the world average (94.1 kg/ha) but yield productions are substantially lower. This indicates to a big gap between the supply and demand of agricultural products, which is widening day by day due to the increasing population of the country.

Sustainable Agriculture

Sustainable productivity in our agricultural ecosystems is therefore an important objective. Sustainable agriculture depends on a whole-system approach whose overall goal is the continuing health of the land and people. Therefore it concentrates on long term solutions to problems instead of short term treatment of symptoms.

There are several important constraints to sustainable agriculture and causing low productivity. They include soil degradation (soil salinity, alkalinity, erosion and soil fertility depletion), depletion of water resources, mismanagement of irrigation systems, the distribution of the land holdings and poor farming practices.

The use of farm inputs, particularly of fertilizers, is inadequate and inefficient. Farm energy use is low. The availability of quality seed is limited. Agricultural research is lagging behind the new challenges. Agricultural extension services are not tuned to modern technology.

The flow of information from research to farmers is inadequate. Coordination between policy, research, extension and farmers could be improved. Disbursement of agricultural credit amounts to over Rs.50 billion per annum, but is less than the requirements and is not reaching small farmers.

An inadequate marketing infrastructure results in high marketing costs and losses. The fertilizer recommendations are too general. Soil testing laboratories are not adequately equipped in terms of manpower and equipment. As a result, the majority of the farmers become resource-poor and can not get benefit and therefore, our crop yields are one of the lowest in the world.

Declining land productivity with reduced crop yields has been also a major problem facing our farmers. The major factors contributing to the reduced land productivity is soil impoverishment caused by continuous cropping without addition of adequate mineral fertilizers and manures. Moreover, negative soil nutrient balances (nutrient removal exceeding nutrient application) during our cropping history have resulted in general deterioration of fertility levels. Sustained, high yield agricultural production can be assured once these negative balances are addressed. Crop fertilization is the main tool available.

Fertilizer has played a key role in helping farmers achieve their high level of production. Fertilizers provide essential plant nutrients which are indispensable for producing sufficient and healthy food for the world’s expanding population. Plant nutrients are therefore a vital component of any system of sustainable agriculture. Nitrogen (N), phosphorus (P), and in recent years, zinc, boron and sulfur are the nutrients of most concern in the grain-production regions. Unfortunately our soils are deficient in Nitrogen (100 %), Phosphorus (90%), Zinc (70%) and Boron (55%). Potassium (K) is generally adequate but its deficiency is emerging rapidly. Deficiencies and responses to other nutrients such as iron (Fe), magnesium (Mg), and other micronutrients are reported for specific crops and areas. When the soil cannot supply the level of nutrient required for adequate growth, supplemental fertilizer applications become necessary.

Prior to the introduction of fertilizes in Pakistan in the early1950s, the use of fertilizers have increased significantly. Total consumption of nutrients in Pakistan has increased from 5 kg/ha in 1966-67 to 133 kg/ha in 2001-2002. However, it is still much lower when compared with other countries of the world and highly unbalanced to produce enough and quality food to meet the country demand. The crop yields in countries using higher fertilizer rates (e.g. Korea, Japan China, Egypt etc) are two to three times more than Pakistan.

One of the factors responsible for stagnating yields and decreasing fertilizer use efficiency is the current unbalanced fertilizer use. Nutrient balances for many cropping systems are negative. The nitrogen and phosphorus are the most limiting nutrients to crop production but their sufficient use by majority of the smallholder farmers become limiting due to their high costs. Indeed a substantial number of farmers do not use fertilizers and the ones who use fertilizers apply below the recommended rates.

In Pakistan various types of fertilizers are used, some are locally manufactured and others are imported. In our country, most of the fertilizer is used on irrigated wheat, cotton, sugarcane and rice crops. On these crops the nitrogen application rate is close to 75-80 percent of the recommendations, compared with about 20-40 percent, depending on the crop, in the case of phosphate. Hardly 1-2 percent of farmers apply potash; that is usually applied to fruit, vegetable, and sugarcane crops only. Micronutrient deficiencies are common but less than five percent of the farmers apply micronutrient fertilizers.

There are several problems which are impeding the balance and efficient use of fertilizers. These are commonly non-availability of specific fertilizers at right time, ever-increasing prices, improper application methods and time, lack of knowledge among farmers about the need for balanced fertilizer applications, adulteration and inadequate grant of soft loans especially for the small farmers, costituting 75 per cent of our farming community.

The increase of fertilizer use efficiency is also related to ensuring the fertilizer quality. At present, apart from some macro fertilizers produced industrially, there are several mixed macro and micronutrient fertilizers, foliar fertilizers, plant growth stimulants which are not controlled by the government. They are circulated with of fertilizer arbitration organizations, therefore the farmers are always suffering from losses once having bought the adulterated or low-quality fertilizers, and the legitimate fertilizer producers and traders suffer from losses and risks.

Balanced fertilization

Balanced fertilization is one of the most important tools to achieve maximum crop yield. Balanced fertilization can be defined as the rational use of fertilizers and manures for optimum supply of all essential nutrients for maximum crop yield which simultaneously ensures efficiency of fertilizer use promotes synergistic interactions and keeps antagonistic interactions out of the crop production system. Fertilizers are not cheap and therefore, it is essential that they should be efficiently and effectively used to produce maximum increase in crop yields so that farmers receive the best possible outputs from their expenses.

Balanced fertilization does not mean a certain definite proportion of nitrogen, phosphorus and potash or other nutrients to be added in the form of fertilizer, but it has to take into account the availability of nutrients already present in the soil, crop requirement and other factors. It should take into account the crop removal of nutrients, the economics of fertilizers and profitability, farmers’ ability to invest, agro-techniques, soil moisture regime, weed control, plant protection, seed rate, sowing time, soil salinity, alkalinity, physical environment, microbiological condition of the soil, cropping sequence, etc. It is not a state but a dynamic concept.

Balance fertilization is invariably the practice, which enable the farmers to approach practically realizable yield potentials in a cost effective and sustainable manner. Balanced fertilization enhances crop yield, crop quality and farm income; corrects soil nutrient deficiencies, and maintains soil fertility. Several field trials on balance fertilization have proved the yield improvement by 50-100 per cent.

According to a (NFDC; 1999) report, balanced use of fertilizers increased the yields of wheat by 77%, sugarcane 100%, rice 25-100% and cotton by 400%. To reap the benefits of balanced use of fertilizers, our farmers must implement the five key practices (a) apply only those nutrients that will result in economic yield increases (b) apply appropriate nutrient rates (c) apply appropriate sources of fertilizer nutrients (d) apply nutrients at appropriate timing (e) apply using the most effective and practical application techniques.

A balanced fertilization strategy is the only way to ensure a sustainable agriculture that can provide the world population with high quality food while minimizing the impact on the environment. All available knowledge about the crop and the environment where it will be grown must be combined to set up the right combination of nutrients to be applied at each step of the fertilization program.

Suggestions

Among the programs of Ministry of Agriculture, the program of agricultural extension on fertilizers is considered a central one aiming at increasing fertilizer use efficiency, crop yield and agricultural product quality, stabilizing and enhancing the soil fertility.

But unfortunately, due to different reasons, due attention was not paid to this program. However, the following suggestions would be fruitful in promoting the balance use and proper management of fertilizers and increasing crop yields and soil fertility.

• Setting up a united network of agricultural extension on fertilizers with the participation of research institutes, agricultural universities, scientific associations and non-governmental organizations, fertilizer producing and trading companies.

• Surveying the current status of fertilizer use of farmers in all key agricultural areas in the whole country. The surveyed data will be processed to find out the advantages and shortcoming in fertilizer use for some main crops.

• Surveying the current status and capacity of fertilizer supply and service of governmental organizations, collective and private organizations, evaluating the supply capacity and requirement of each fertilizer kind at localities according to short- term and medium -term plants.

• Setting up the network of stable and long-term field experiment on some soil types for some crops in all agro-ecological zones in the whole country in order to exactly assess the nutrient supplying capacity of soils, factors limiting the fertilizer use efficiency (soils, climate and weather, management level, intellectual standard of the people...), direct and residual efficiency of main fertilizer to serve as a basis for establishing the formulae of reasonable fertilization.

• Setting up a network of field experiments to assess the environmental impacts of fertilizers, especially the impacts of fertilizers on soil fertility and agricultural product quality, besides, through this research system identifying the relationship between fertilizers and IPM.

• Organizing the training courses to provide the local extension workers with new knowledge and update new knowledge for them.

• Organizing the training for farmers on the role of each nutrient, symptoms of nutrient shortage and method of reasonable and efficient fertilizer through the farmer’s field schools using the most simple and effective methods.

• Organizing the information and propaganda on fertilizer use guides as well as introduction of new fertilizer through mass-media.

• Printing the fertilizer use guides. In the short term, apart from specific information, a new issue of agricultural extension on fertilizers can be carried out at the periodical of Pakistan Soil Science Society or the periodical of Department of Agriculture extension.

• Working out the regulations on fertilizer quality control aiming at preparing the fertilizer legislation.

• Carrying out the activities of cooperation on agricultural extension on fertilizers with in-country and foreign organizations as well as testing the efficiency of new fertilizers manufactured by in-country as well as foreign companies.

• Establishing the technical support fund to help the enthusiastic farmers having difficulties to form the key farmer class at the grassroots units.

• Developing the long-term human resource development program to improve qualifications of researchers and extension workers to PhD level and also provide for short-term trainings to equip them with knowledge and skills in important areas. Besides, career structure and incentive framework may be introduced to reward quality research and extension work.

Expected Outputs/Benefits

• The farmers provided with basis knowledge of fertilizer: Kind, composition, properties, method of storage, fertilizer use guide (not only for agricultural crops but also for forest trees).

• Agricultural output increase due to increase in crop yield.

• Agricultural product value increase due to increase in quality.

• Fertilizer cost for a product unit reduced, hard foreign currencies economized due to reasonable fertilizer use.

• Balanced fertilization reduces the incidence of plant diseases, such as red-leaf stem blight in cotton as found in various provinces of China. Natural improvements in the plant's ability to resist disease infections result in less need for insecticides and fungicides, which lowers production costs for farmers and reduces chances for negative environmental impact.

• Environmental pollution protected due to decrease in gaseous nitrogen looses as well as nitrate loss by leaching.

• Soil fertility stabilized and enhanced.

In summary all embracing efforts should be made to educate farmers to practice balanced use of fertilizers. Of late, some fertilizer companies and associations have come forward to educate the villagers, publication of literature in regional languages related to balanced use of fertilizers for higher crop yields in a sustainable way. The actual time has come; the farmers, researchers and other related communities should come forward and act in this respect.

The chemical fertilizers are very expensive therefore, should be used judiciously and use manures along with chemical fertilizers for improving the crop yield and soil productivity in a sustainable way. Many more activities are being planned to promote the balanced use of fertilizers. And it is hoped that all these efforts would lead to desired awareness and as a result balanced fertilizer use would become a reality in near future.