Restoration of soil health for achieving sustainable growth in agriculture.

Ahmad, Bashir ; Ahmad, Munir ; Gill, Zulfiqar Ahmad 等

About 2.2 million hectares of land in Pakistan is under cultivation. Approximately, 75 percent of this area is afflicted with various types of soil problems: Most important of these include water logging and salinity; nutrient depletion, soil compaction and soil erosion. These menaces are resulting in inefficient use of various inputs and reduction in cropping intensity, land use intensity, yield of crops, income, employment, etc. Empirical evidence suggests that the intensity of these problems is on the increase and has been posing serious threats to the sustainable growth of agriculture. This paper reviews the causes and effects of various soil health related problems and also makes an attempt at evaluating different amendments to reclaim the problematic soils.

I. INTRODUCTION

Total geographical area of Pakistan is 79.61 million hectares (re.ha.). Area under cultivation is 21.59 m.ha.; of which, only 5.34 m.ha. (i.e., 25 percent) is free from soil limitations and is fit for intensive agriculture [Mian and Mirza (1993)]. The remaining agricultural lands have various types of problems including formation of slow permeability, water logging, salinity and sodicity, and wind and water erosion. Thus, on an average, three out of four hectares of cultivated land in Pakistan are in poor health. This in turn is causing temporary or permanent decline in the productive capacity of the land. Therefore, poor soil health is posing serious threat to the sustainable growth of agriculture. The most important on-farm effects of land are summarised in Table 1.

The remaining paper is divided into five sections. Section II gives details regarding water logging and salinity. Section III deals with the nutrient depletion and management. Section IV reviews the causes and effects of soil compaction. Section V is devoted to soil erosion, its causes and effects. Concluding remarks and researchable areas appear in Section VI.

II. WATERLOGGING AND SALINITY

Historically, there has been very little problem of waterlogging and salinity in the Indian sub-continent during the nineteenth and early twentieth centuries under the prevailing barrage controlled irrigation systems. These systems thinly spread water over large agricultural area. Overtime, seepage from canals and field percolation from continuous irrigation have caused the ground water to rise and the salts to move upward through capillary action that resulted into soil salinity or alkalinity and waterlogging.

Pakistan has two principal sources of irrigation that are surface water and groundwater. More than 100 million acre feet (MAF) of surface water is being diverted into the canal systems in the Indus plain. There are thus substantial losses in water in the system. Under the present conditions, the overall water use efficiency of the system is about 59 percent [Pakistan (1988)]. The chemical quality of the surface water shows that the total dissolved salts (TDS) contents commonly fall in the range of 150 to 250 mg/litter, which is excellent for irrigation, drinking and industrial purposes [Ghossemi et al. (n.d.)]. On the other hand, the groundwater quality varies depending on the climatic factors, nature of the surface flow, topography, extent of seepage and irrigation practices. The quality deteriorates as one goes across the plain from upstream to down stream towards the Arabian Sea and the TDS values range from 1000 mg/litter to 3000 mg/litter [Ghossemi et al. (n.d.)]. The ground water pumpage is about 44 MAF [Mohtadullah et al. (1993)]. Of this, about 32 MAF is used for irrigation showing water use efficiency of 73 percent. As regards the quality of ground water, about 25 percent of the tubewell water in Punjab is of marginal quality and 50 percent of the water is not safe for irrigation purposes. The situation is even worse in Sindh but the quantity of underground water used for irrigation in Sindh is much less [Malik et al. (1991)]. According to some estimates, about 7500 million tonnes (MT) of salts are present in the upper 100 meters of the groundwater reservoirs of the Indus Plain [ICID (1991)]. About 50 MT of salts are being added to the system every year through the canal irrigation water [Qureshi (1993)]. While 100 MT of salts are being added every year to the soil surface through tubewell irrigation [ICID (1991)]. Unfortunately, present export of salts out of the system is about 10-15 MT every year [Qureshi (1993)]. However, this figure is expected to rise upto 25-30 MT every year on the completion of the Left Bank Outfall Drain (LBOD) stage I project. Despite all this, the problem of salinity/ alkalinity is likely to aggravate further as the addition of salts is much more than the export of salts from the system.

Table 2 shows very serious concerns regarding the present situation of salinity/sodicity in Pakistan. Total affected area with salinity is about 6.2 m.ha.; of which, 4.3 m.ha, is severely saline/saline sodic and 78 percent (3.40 m.ha.) of this area is not even being cultivated. Major portion of this uncultivated area is approximately equally distributed in Punjab and Balochistan provinces. As regards the area with high water table, it is not easy to assess. However, some of the estimates show that the area with water table at 0-5 feet depth is 2 m.ha. in the month of June, but this figure increases to 5.2 m.ha. in the month of October [Pakistan (1997)]. Such a situation is considered disastrous for agricultural growth [Pakistan (1988)].

According to Javed (1991), a study conducted in Sheikhupura district, cropping and land use intensities were found about 11 percent and 62 percent less, respectively, on farms where the water table depth was 0-5 feet as compared to farms where the depth was 10 to 15 feet. The proportionate area under rice was found higher. It was lower for wheat and sugarcane on lands having water table depth of 0-5 feet as compared to other categories--5-0 feet and 10-15 feet. However, the yields of wheat, sugarcane and burseem were 2 to 4 times lower on the farms with high water table. Nadeem (1989), considering different levels of salinity/sodicity in Sheikhupura district, provided the same type of results. Another study by i.e., Mustafa (1991), conducted in the same district concluded that the wheat yield per acre on degraded soils, having PH and EC levels higher than 6.5 and 4.0, respectively, was half of that of the yield on non-degraded soils. Moreover, the use of inputs was found many times lower on degraded soils than that on non-degraded soils. As regards the reasons of land degradation, fifty percent of the farmers considered the scarcity of irrigation water, poor quality of the tubewell water was viewed as a source by 16 percent of the farmers and 10 percent of them blamed the lack of drainage facility. About 31 percent of the farmers mentioned no reason.

In sum, the available empirical evidence shows that the decline in productivity because of salinisation ranges from 25 to 70 percent on moderately salt affected soils and it approaches 100 percent in areas where the problem of salinisation is severe. At the present stage of our development and in the face of explosive population growth, Pakistan economy cannot afford to see its crop yield declining with low crop germination rates and poor crop establishment in the fields. Restoration of soil health from the menaces of water logging and salinity deserves highest priority to ensure sustainable food security to the fast growing population of Pakistan.

In order to estimate the expected benefits from the improvement of degraded soils due to salinity/sodicity, economics of the use of various amendments has been determined. The experimental data used for this purpose were generated by the Department of Soil Science, University of Agriculture, Faisalabad during the period 1980-81 to 1984-85. These experiments were conducted at the farmer's fields for two soil series, i.e., Khurrianwala and Gandhara in Shahkot area of district Sheikhupura. There were four treatments: (1) T1 Control (leaching with saline-sodic ground water); (2) T2 Subsoiling (SS) (50 cm deep, 150 cm apart crosswise furrows); (3) T3 Gypsum (GYP) (@ 100 percent GR (Gypsum Requirement); and (4) T4 Subsoiling plus gypsum (SS+GYP). There were nine replications making a total of 36 plots each for Khurrianwala and Gandhara series. During the period of these experiments, rice-wheat rotation was practised.

The experimental data thus generated were analysed by using the partial budgeting technique recommended by CIMMYT (1988) and Chaudhry et al. (1995). The analyses are presented in Appendices I and II, which show that the best amendment for farmer's practice is gypsum for the reclamation of salt affected soils for Khurrianwala series and gypsum + subsoiling for the Gandhara series.

III. NUTRIENT DEPLETION AND MANAGEMENT

(i) Declining Soil Nutrient Status

There are different crop ecological zones in Pakistan/Punjab. In each zone, specific crop rotations are being practised. For example, in the rice-wheat cropping system, rice and wheat is the dominant crop rotation, where wheat follows the rice crop (Table 3). Traditionally, wheat and rice were grown as single crops in rice-fallow and fallow-wheat cropping patterns. Similarly, in the cotton wheat cropping system, wheat and cotton is the dominant crop rotation.

Major proportion of the total cropped area in various crop ecological zones is occupied by exhaustive crops: For example, in the rice - wheat cropping zone about 92 percent of the total cropped area is occupied by wheat, rice and fodder (Appendix III). Pulses, which help in improving the soil fertility, occupy only one percent area of the total cropped area. Similarly, in other crop ecological zones, with the exception of Mungbean-wheat cropping system, the area occupied by the leguminous crops is very small (Appendix III).

Besides the domination of exhaustive crops, the problem of declining soil nutrient status is getting more serious with the increasing cropping intensities in various zones. Table 4 indicates that the overall cropping intensity has substantially increased over the period 1960-1990 in various zones of the Punjab. However, declining trend has been observed during this period in rainfed area.

The repeated cultivation of same crops and nutrient exhaustive cropping pattern year after year in various crop ecological zones has led to degradation and depletion of land resource. Due to excessive removal and less application, there is a net negative balance of all the major nutrients even when the nutrients are applied at recommended doses of fertiliser [Zia et al. (1992)]. In rice-wheat cropping system, the soils are also deficient in Zinc. The use of "Octa" a mixture of crop nutrients (i.e., Zinc, Boron, Manganese, Sulfur, Magnesium and Copper), for increasing the availability of micro nutrients has improved the paddy yield [Ashraf (1984-85)]. Unless adequate amounts of nutrients are applied, it will be difficult to sustain the yield of rice-wheat system in the long-run.

(ii) Poor Efficiency of Applied Fertiliser

Consumption of fertiliser in Pakistan has substantially increased overtime. However, crop yields have not increased proportionately indicating poor fertiliser use efficiency. Empirical work shows that nitrogen use efficiency for rice varies from 25 percent to 80 percent depending upon farmers practices and soil health, while the efficiency of phosphorous is 15 to 25 percent [Zia et al. (1992)]. Efficiency of potash is observed about 80 percent under wet land rice, while the zinc is found deficient in 70 percent of the soils and its efficiency hardly exceeds 10 percent [Zia et al. (1992)].

(iii) Imbalaneed Use of Fertilisers

Imbalanced use of plant nutrients has also been one of the major causes of low productivity of most of the crops. The ratio of nitrogenous fertilisers to phosphatic fertilisers has improved from 8:1 to 4.27:1 over the period 1970-1996 [Pakistan (1997)]. This ratio needs to be further narrowed down to 1:1 in order to obtain higher yields.

(iv) Declining Soil Organic Matter

The major sources of organic matter are farm yard manure, green manures and crop residues. The use of farm yard manure is limited because dung is widely burnt as a source of fuel. As regards the crop residues, wheat straw and rice straw are used for feeding the animals. Further rice straw is also burnt as a source of fuel. Sesbania is one of the most suitable green manure for the wheat - rice rotation provided it is sown around May 20 and allowed to grow for 40 days; while, rice may be transplanted in 2nd week of July [Zia et al. (1992a)]. Unfortunately, this practice is very limited.

Addition of nutrients to soil take place through fertilisers, farm yard manure, irrigation water, flood waters, flood silt, rain, etc. These nutrients are basically mined through crops, volatilisation, denitrification, leaching, water erosion, etc. Table 5 indicates very critical situation regarding the nutrient balance for all the provinces in Pakistan. Use of nutrients is more than the addition to the soil and the deficit is increasing over time in all the provinces. Exception is only of Punjab where deficit of nitrogen contents has declined over the years.

It is expected that most of our soils under various cropping systems will become still more deficient in major macro and micro nutrients unless appropriate measures are taken to avert this situation. The fertility status and physical condition of these systems can be improved by using green manure that will help in realising high yields of crops [Zia et al. (1992a)]. Moreover, legumes also help sustain soil fertility through following ways: (1) potential to make substantial contribution to the nitrogen economy of the cropping system; (2) often exert favourable influence on several other soil fertility parameters through their extensive and deep root systems; (3) have ability to extract nutrients from deep soil layers; (4) utilise insoluble or fixed form of nutrients like phosphorous, and make them available to the succeeding crops; and (5) crops like sesbania and their incorporation improves physico-chemical properties of saline-alkali soils leading to increased growth and yields of subsequent crops [Ladha et al. (1996)]. Legumes even save the use of nitrogenous fertilisers and also improve the soil health [Joshi (1996)].

IV. SOIL COMPACTION

Soil compaction is caused by concentration of salts, ploughing at higher moisture levels, frequent use of tractors and implements, increased use of irrigation water and less use of animal and crop wastes. The loss of micro and macro pore spaces, as a result of compaction, reduces infiltration capacity, restricts gaseous exchange in soils and hinders most important biological activities that are essential for plants [Majeed (1989)].

According to Chaudhry (1990), there are three types of hard pans, that are plow pan, clay pan and sodic pan. A plow pan develops due to continuous ploughing at a shallow depth over years. Frequency of these ploughings with tractor varies from 4 to 5 times in fields of various crops [Ahmad et al. (1994)]. Plow pan, that develops normally at a depth of 20 cm, restricts water movement and results in accumulation of salts carried with the irrigation water on the upper layer of the soil with the passage of time. As a consequence, plow pan reduce land productivity significantly. The experimental results show that breakage of plow pan using non-conventional tillage practices increases the yield by 5 to 20 percent of wheat sown after the harvest of Basmati 385 (Table 6). Moreover, incremental benefit cost ratio over the control show that the highest returns from the investment were obtained where chisel plow or M. B. plow was used along with other implements (Table 7).I

Sodic pan develops in sodic soils or through the use of brackish ground water for irrigation. Development of such a pan results in negligible permeability as the clay sediments seal the soil pores on their downward movement [Sabir et al. (n.d.)]. Such a soil behaves like concrete. Results of breakage of such a pan with various treatments are presented in Tables 8 and 9 for wheat crop at a site in Faisalabad district. These results show that the wheat yield was about 30 percent higher where gypsum was applied at the rate of 75 percent requirements compared with 50 percent requirements. Based on marginal analyses, option II (75 GR + subsoiler) appears most feasible for farmer's adoption. It promises a return of Rs 127 for every Rs 100 investment (Table 9).

V. SOIL EROSION

Land degradation is also caused by soil erosion. A considerable fertile area has already been abandoned as soil erosion has rendered it unproductive. About 4.8 million hectares are affected from wind erosion (Table 10). Deserts of Thai, Cholistan, Thar and Kharan are the most affected ones [Rashid et al. (1998)]. Table 10 further shows that about 11.2 m.ha. are affected by water erosion; out of which, 4.3 m.ha. are in NWFP and FATA, 2.6 re.ha, in Balochistan, 2.3 m.ha. in Northern areas and 1.9 re.ha, in the Punjab. Water erosion depletes the soil fertility and accelerates silting up of irrigation system [Qureshi and Muhammed (n.d.) and Mian and Mirza (1993)].

Water erosion depends on different factors like, nature of soil, density of vegetative cover, amount and intensity of rainfall. It is intensified by improper methods of cultivation, overgrazing, burning and activities of rodents. Water erosion can have significant adverse effects on soil productivity: Most of the organic matter and nutrients are present in the upper layers of soil that are mostly lost in the eroding water. Erosion also degrades the soil's structure and diminishes its water holding capacity [Naidu et al. (1998)]. Results, though old, of a conservation project showed that the treated or reclaimed lands performed much better than the eroded land requiring conservation in terms of the use of various inputs, output per acre of various crops, gross and net income, etc. Table 11 indicates that the index of inputs use increased from 100 to 332. In terms of output the least increase was observed in case of wheat that was 123 percent and highest increase was observed in lentil, i.e., 382 percent. Per acre net income doubled on the reclaimed (treated) soils. Cropping intensity increased from 32 percent to 119 percent after reclaiming the soil. Another important result was that the proportionate area under grasses and trees increased from zero to 14 percent.

VI. CONCLUSION AND RESEARCHABLE AREAS

Land degradation is essentially a serious problem in Pakistan. Various forms of land degradation, i.e., water logging and salinity, nutrient depletion, soil compaction, soil erosion, etc., are resulting in inefficient use of various farm inputs and reduction in cropping and land use intensity, crop yields, farmer's income, employment, etc. Nevertheless there are still many aspects that need to be researched, which include: (1) Impact of different quality tubewell water on soil characteristics, input use efficiency, output of various crops and land use and cropping pattern; (2) Impact of use of city drainage water including industrial effluents on, resource productivity, quality of output, environmental hazards and farm income; (3) Economics of various drainage systems like the drainage, surface drainage etc. at farm level; (4) Economics of improvement of drainage facilities and drainage effluent disposal; (5) Economics of use of brackish drainage effluent for agriculture and industry; (6) Factors responsible for the adoption of land reclamation technologies such as are Gypsum application, Sub-soiling, Green manuring, Farm yard manure applications, EM technology and other soil amendments; (7) Studies into the nutrient management on degraded soils which may include economics of alternative crop rotations on degraded soils in various zones, economics of use of macro, micro and trace nutrient elements under various cropping systems, determination of optimum N, P, K etc. ratios for various crops under varied crop ecological conditions and economics of green manuring; (8) Studies on the impact of various types of soil compaction on crop productivities and farm income; (9) Economics of soil conservation with special reference to watershed areas; (10) Economics of growing fruit plants in gullies in different ecological zones of rainfed areas; (11) Economics of gullied land development under different climatic conditions; and (12) Economics of growing of cover crops/legumes for moisture conservation.

Comments

I would like to applaud the efforts of the authors who have highlighted the important issue of land soil degradation threatening the very sustainability of agriculture in the Indus Basin. The paper describes the state of Indus Agriculture in the introduction and covers hosts of soil problems namely twin menace of waterlogging and salinity, nutrition depletion and management, soil compaction, and soil erosion in section two through five. In the last section conclusions and policy implications are obtained. The authors have made a useful beginning by surveying the literature on a very vital issue confronting Pakistan's agriculture. Nevertheless the paper is narrow in scope and content while dealing a macro issue only in Rice-Wheat crop zone of Punjab. I will come to the land degradation issue a little later. As customary, I will pinpoint some editorial changes.

I would like to point few typo errors. For instance on page 9 and 17 of the paper "Joshi (1966) should be read as Joshi (1996). On page 2 seline is probably sodic and berseem is mis-spelled and similarly on page 13 and 14 lentil is misspelled as lent. These are just a few pinpricks to be reckoned with. The table on page 5 is quoted without a source. On page 6 of the paper authors have shown that productivity declined from 25 to 70 percent due to salinity in moderately affected soils and 100 percent in severely saline areas. The authors have not quoted any source. On page 8 authors have suggested to narrow the NP ratio from 4.27:1 down to 1:1 but the soil scientists and literature demonstrates the ideal ratio as 2:1. Again in Table 5.6 and 9 sources of data are missing. In the absence of complete detail of data sources, one cannot discern the drivel of marginal analysis i.e., marginal costs and marginal benefits.

In concluding the paper authors just pinpointed some researchable topics which are related directly or indirectly with land degradation. Coming back to the title of the paper, it seems that it covers all the 64 soil series covering the farm areas of Pakistan. The authors have only reviewed the studies undertaken in Khurianwala and Gandhara series in the rice-wheat zone. Thus the conclusion drawn from these studies cannot be generalised for whole of Pakistan. The authors may consider the change the more commensurate with the contents of the paper.

In the end I would suggest that land degradation and sustainability may be defined in wider context. There are several definitions of land degradation. Recently Sohail (1998) has completed a study on Rural Poverty and Land Degradation where he has provided a comprehensive survey of Land Degradation Literature. Soil Survey of Pakistan done extensive work in collaboration with Salinity Research Institute and NESPAK. Example of Land Degradation can be found in erosion, salinisation, water logging, vegetation depletion, fertility loss, soil structure change, and pollution of soil: No country has comprehensive estimates of the productivity losses due to land and soil degradation or the pace of degradation from current farm practices. Therefore, there is a demonstrated need for thorough review of experimental and field data and sharp focus on robust and cheap methods of data collection and its collation for better understanding of the physical process involved. In order to address the issue of land degradation, country is to be classified into distinct land and water management zones and develop management strategies to help avoid land degradation.

Zakir Hussain Rana

Ministry of Food, Agriculture and Livestock, Islamabad.

Appendices

Appendix I

Partial Budget for the Project Period (1980-81 to 1984-85)
Khurrianwala Soil Series

 Treatment

Item Control SS

I. Gross Field Benefits
(a) Wheat Grain
 i. Gross Output (Kg/Acre) 2892 4188
 ii. Adjusted Output (Kg/Acre) 2458 3560
 iii. Gross Field Benefits @
 Rs 6/Kg (Rs/Acre) 14749 21359
(b) Wheat Bhusa (Straw)
 i. Gross Output (Kg/Acre) 2892 4188
 ii. Adjusted Output (Kg/Acre) 2458 3560
 iii. Gross Field Benefits @
 Rs.0.95/Kg (Rs/Acre) 2335 3382
(c) Rice Grain
 i. Gross Output (Kg/Acre) 2052 3193
 ii. Adjusted Output (Kg/Acre) 1744 2714
 iii. Gross Field Benefits @
 Rs 5.55/Kg (Rs/Acre) 9594 14927
(d) Rice Bhusa (Straw)
 i. Gross Output (Kg/Acre) 8699 12153
 ii. Adjusted Output (Kg/Acre) 7394 10330
 iii. Gross Field Benefits @
 Rs 0.12/Kg (Rs./Acre) 887 1240
Total Gross Field Benefits
 (Rs/Acre) 27565 40917

II. Total Costs That Vary
 i. Gypsum @ 76 Bags Per Acre
 in Treatment GYP @ Rs 29
 Per Bag (Rs/Acre)
 ii. Gypsum @ 56 Bags Per Acre
 in Treatment SS+GYP @
 Rs 29 Per Bag (Rs/Acre)
 iii. Subsoiling Once
 (Rs Per Acre) 741
 iv. Labour Cost for GYP
 Application 4 Man Days in
 Treatment GYP @ Rs 70/Man
 Day (Rs/Acre)
 v. Labour Cost for GYP
 Application (2.83 Man
 Days @ Rs 70/Man Day
 in Treatment SS+GYP)
 Harvesting, Threshing,
 Cleaning Cost 2100
 Total Costs That Vary 2841

III. Net Field Benefits (Rs/Acre) 27565 38076

IV. Average Annual Benefits
 (Rs/Acre) 6891 9519

 Treatment

Item GYP SS+GYP

I. Gross Field Benefits
(a) Wheat Grain
 i. Gross Output (Kg/Acre) 5711 5091
 ii. Adjusted Output (Kg/Acre) 4854 4327
 iii. Gross Field Benefits @
 Rs 6/Kg (Rs/Acre) 29126 25964
(b) Wheat Bhusa (Straw)
 i. Gross Output (Kg/Acre) 5711 5091
 ii. Adjusted Output (Kg/Acre) 4854 4327
 iii. Gross Field Benefits @
 Rs.0.95/Kg (Rs/Acre) 4612 4110
(c) Rice Grain
 i. Gross Output (Kg/Acre) 2979 2488
 ii. Adjusted Output (Kg/Acre) 2532 2115
 iii. Gross Field Benefits @
 Rs 5.55/Kg (Rs/Acre) 13927 11631
(d) Rice Bhusa (Straw)
 i. Gross Output (Kg/Acre) 9358 9908
 ii. Adjusted Output (Kg/Acre) 7954 8422
 iii. Gross Field Benefits @
 Rs 0.12/Kg (Rs./Acre) 954 1011
Total Gross Field Benefits
 (Rs/Acre) 48619 42717

II. Total Costs That Vary
 i. Gypsum @ 76 Bags Per Acre
 in Treatment GYP @ Rs 29
 Per Bag (Rs/Acre) 2204
 ii. Gypsum @ 56 Bags Per Acre 1624
 in Treatment SS+GYP @
 Rs 29 Per Bag (Rs/Acre)
 iii. Subsoiling Once
 (Rs Per Acre) 741
 iv. Labour Cost for GYP
 Application 4 Man Days in
 Treatment GYP @ Rs 70/Man
 Day (Rs/Acre) 280
 v. Labour Cost for GYP
 Application (2.83 Man
 Days @ Rs 70/Man Day
 in Treatment SS+GYP) 198
 Harvesting, Threshing,
 Cleaning Cost 3771 2814
 Total Costs That Vary 6255 5377

III. Net Field Benefits (Rs/Acre) 42364 37340

IV. Average Annual Benefits
 (Rs/Acre) 10591 9335

Updated data by using latest prices as reported by
Ahmad et al. (n.d.).

Appendix II

Partial Budget for the Project Period (1980-81 to 1984-85)
Khurrianwala Soil Series

 Treatment

Item Control SS

I. Gross Field Benefits
(a) Wheat Grain
 i. Gross Output (Kg/Acre) 1052 1366
 ii. Adjusted Output (Kg/Acre) 894 1161
 iii. Gross Field Benefits @
 Rs 61/Kg (Rs/Acre) 5364 6967
(b) Wheat Bhusa (Straw)
 i. Gross Output (Kg/Acre) 1052 1366
 ii. Adjusted output (Kg/Acre) 894 1161
 iii. Gross Field Benefits @
 Rs 0.95/Kg (Rs/Acre) 849 1103
(c) Rice Grain
 i. Gross output (Kg/Acre) 2414 2414
 ii. Adjusted output (Kg/Acre) 2051 2052
 iii. Gross Field Benefits @ 11284 11287
 Rs 5.55/Kg (Rs/Acre)
(d) Rice Bhusa (Straw)
 i. Gross Output (Kg/Acre) 6344 6466
 ii. Adjusted Output (Kg/Acre) 5393 5496
 iii. Gross Field Benefits @
 Rs 0.12/Kg (Rs/Acre) 647 660
Total Gross Field Benefits (Rs/Acre) 18145 20017

II. Total Costs That Vary
 i. Gypsum @ 152 and 184 Bags for
 Treatment GYP and SS+GYP
 @ Rs 29 Per Bag (Rs/Acre)
 ii. Subsoiling Once (Rs Per Acre) 741
 iii. Labour Cost for GYP
 Application 7.7 Man Days in
 Treatment GYP and 9.3 Man
 Days in SS+GYP @
 Rs 70/Man Day (Rs/Acre)
Harvesting, Threshing, Cleaning
 Cost 373
Total Costs That Vary 1114

III. Net Field Benefits (Rs/Acre) 145 18903

IV. Average Annual Benefits
 (Rs/Acre) 4536 4726

 Treatment

Item GYP SS+GYP

I. Gross Field Benefits
(a) Wheat Grain
 i. Gross Output (Kg/Acre) 3459 3477
 ii. Adjusted Output (Kg/Acre) 2940 2955
 iii. Gross Field Benefits @
 Rs 61/Kg (Rs/Acre) 17641 17733
(b) Wheat Bhusa (Straw)
 i. Gross Output (Kg/Acre) 3459 3477
 ii. Adjusted output (Kg/Acre) 2940 2955
 iii. Gross Field Benefits @
 Rs 0.95/Kg (Rs/Acre) 2793 2808
(c) Rice Grain
 i. Gross output (Kg/Acre) 4223 4723
 ii. Adjusted output (Kg/Acre) 3589 4014
 iii. Gross Field Benefits @ 19741 22079
 Rs 5.55/Kg (Rs/Acre)
(d) Rice Bhusa (Straw)
 i. Gross Output (Kg/Acre) 9865 12739
 ii. Adjusted Output (Kg/Acre) 8385 10828
 iii. Gross Field Benefits @
 Rs 0.12/Kg (Rs/Acre) 1006 1299
Total Gross Field Benefits (Rs/Acre) 4118 43919

II. Total Costs That Vary
 i. Gypsum @ 152 and 184 Bags for
 Treatment GYP and SS+GYP
 @ Rs 29 Per Bag (Rs/Acre) 4408 5336
 ii. Subsoiling Once (Rs Per Acre) 741
 iii. Labour Cost for GYP
 Application 7.7 Man Days in
 Treatment GYP and 9.3 Man
 Days in SS+GYP @
 Rs 70/Man Day (Rs/Acre) 539 651
Harvesting, Threshing, Cleaning
 Cost 3725 4009
Total Costs That Vary 8672 10737

III. Net Field Benefits (Rs/Acre) 32509 33182

IV. Average Annual Benefits
 (Rs/Acre) 8127 8296

Updated data by using latest prices as reported by Ahmad
et al. (n.d.).

Appendix III

 Cropping Patterns of Various Zones of the Punjab
 During 1990

 Crop Area as Percent of Total Cropped Area

 Maize for Jowar/Bajra
Zone Wheat Rice Grain for Grain Barley

Rainfed 51 * 21 12 1

Rice-Wheat 39 37 * * *

Cotton-Wheat 39 2 * * *

Mixed Cropping 39 4 5 1 *

Mungbean Wheat 23 * * * 1

Bakhar
Punjab 39 10 1 2 1

 Cropping Patterns of Various Zones of the Punjab
 During 1990

 Crop Area as Percent of Total Cropped Area

 Oil
Zone Cotton Sugarcane Tobacco Seed Pulses

Rainfed * * * 4 7

Rice-Wheat * 1 * 1 1

Cotton-Wheat 41 2 * 1 *

Mixed Cropping 8 13 * 1 *

Mungbean Wheat 2 2 * 1 52

Bakhar
Punjab 15 3 * 2 6

 Cropping Patterns of Various Zones of the Punjab
 During 1990

 Crop Area as Percent of Total Cropped Area

Zone Fodders Vegetable Orchards Others

Rainfed 2 1 1

Rice-Wheat 16 3

Cotton-Wheat 12 1 1

Mixed Cropping 24 1 1 1

Mungbean Wheat 19

Bakhar
Punjab 16 2 2 1

Source: Pakistan (1990)

* Value less than 0.5.

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(1) Razzaq et al. (1993) conducted this study at adoptive research farm at Sheikhupura and farmer's fields. Trials were laid out on clay loam soils for wheat after the harvest of Basmati 385 on 10 similar sites with three replicates.

Bashir Ahmad, Munir Ahmad and Zulfiqar Ahmad Gill are associated with the Faculty of Agricultural Economics and Rural Sociology, University of Agriculture, Faisalabad.

Table 1
Causes and Indicators of Resource Degradation

 Effects of Resources
Resource Base Possible Causes Degradation

Increase in Salinity/ Poor design of the Reduction in yields
 Water Logging irrigation system and fall in factor
 resulting in high productivities
 seepage of water

 Application of poor Reduced land use and
 quality tubewell cropping intensities
 water

Increased Nutrient Continuous practice Reduction in yield
 Depletion of the same rotation and fall in factor
 productivities

 Continuous cropping Declining efficiency
 of exhaustive crops of various
 fertilisers

 Reduction in area
 under leguminous
 crops

 Declining organic
 matter

Formation of Increased use of Reduction in yields
 Hard Pan machines and reduced factor
 intensities

 Use of brackish well
 water

Devegetation Indiscrintinate Barren fields and
 cutting of trees Increased erosion

Table 2
Extent of Salinity/Sodicity in Pakistan * (000 Hectares)

 Slightly
 Saline/ Moderately Severely
 Saline-Sodic Saline/Saline Saline/Saline
Province (a) Sodic (b) Sodic (c) Total

Punjab
Total 472.4 804.8 1390.3 2667.5
Cultivated 472.4 804.8 235.5 1512.0
Uncultivated -- -- 1155.5 1155.5

Sindh
Total 118.1 324.7 1666.8 2109.6
Cultivated 118.1 324.7 708.2 1151.0
Uncultivated -- -- 958.6 958.6

NWFP & FATA
Total 5.2 25.7 17.6 48.5
Cultivated 5.2 25.7 0.9 31.8
Uncultivated -- -- 16.7 16.7

Balochistan
Total 3.0 74.6 1270.3 1347.9
Cultivated 3.0 74.6 31.4 109.0
Uncultivated -- -- 1238.9 1238.9


Pakistan
Total 598.7 1232.8 1558.6 6173.5
Cultivated 598.7 1232.8 4345.0 2803.8
Uncultivated -- -- 3369.7 3369.7

* The extent is estimated for an area of about 20.6 m. ha. of Punjab,
9.2 m. ha. of Sindh, 9.1 m. ha. of NWFP and FATA and 30.5 m. ha. of
Balochistan covered through reconnaissance soil survey.

(a) Includes soils having mainly surface or patchy salinity/sodicity.

(b) The figures given for cultivated area under these soils include a
small extent of uncultivated soils which are expected to be brought
under cultivation in very near future due to their location within
irrigation command.

(c) The cultivated area reported under this category has relatively
low discernible salinity but the soils are dense (impermeable) with
severe sodicity problem.

Table 3
Rotations Followed in the Rice--Wheat System

Rotation Percent of Total

Rice-Wheat-Rice 71.8
Rice-Berseem-Rice 8.50
Rice-Watermelon-Rice 2.70
Rice-Fallow-Rice 6.50
Others 10.50
Total 100.00

Source: Ashraf (1984-85).

Table 4
Cropping Intensities in Various Zones of
the Punjab Over Time

 Cropping Intensity

Zone 1960 1980 1990

Rainfed 122 122 117
Rice-Wheat 107 156 173
Cotton-Wheat 103 125 165
Mixed Cropping 116 127 142
Mungbean-Wheat 94 104 112
Punjab 124 141

Sources: Pakistan (1960, 1980, 1990).

Table 5
Provincial Nutrient Balances 1985-86 and 1995-96 (Kg/hac)

 [P.sub.2]
 N [O.sub.5] [K.sub.2]O

 1985-86 1995-96 1985-86 1995-96 1985-86 1995-96

Punjab -19.19 -8.57 -10.45 -10.73 -23.69 -27.27
Sindh -5.0 -6.95 -8.54 -11.72 -7.69 -17.32
NWFP -9.52 -10.73 -8.35 -10.74 -20.89 -29.73
Balochistan -21.56 -27.15 -7.43 -11.36 -14.18 -25.57
Pakistan -15.61 -9.39 -9.78 -10.9 -20.00 -25.79

Table 6
Effect of Breakage of Plow Pan with Different Tillage Practices
on the Yield of Wheat Crop

 Yield (Kg/Ha)

Treatment 1986-87 1987-88 1988-89 1989-90

Cultivator (5) 1311 1555 1661 1726

Rotavator (1) + 1354 1656 1690 1845
Cultivator (3)

Disc. Harrow (2) + 1428 1764 1806 1944
Cultivator (2)

Rotavator (1) + 1478 1818 1786 2051
Chisel Plow (2)

Disc Harrow (1) + 1528 1832 1850 2288
Chisel Plow (2)

M.B. Plow (1) + 1493 1825 1893 2288
Disc Harrow (1)

 Av. Percent
 Yield Over
Treatment (kg/hac) Check

Cultivator (5) 1563 --

Rotavator (1) + 1637 4.69
Cultivator (3)

Disc. Harrow (2) + 1736 11.03
Cultivator (2)

Rotavator (1) + 1784 14.13
Chisel Plow (2)

Disc Harrow (1) + 1875 19.91
Chisel Plow (2)

M.B. Plow (1) + 1875 19.91
Disc Harrow (1)

Source: Razzaq et al. (1993).

Table 7
Economics of Breakage of Plow Pan with Different Tillage Practices

 Gross Change in Gross
 Expenditure Cost over Income
Treatment (Rs/Acre) Control (Rs/Acre)

Cultivator (5) 2105.63 -- 4181.71

Rotavator (1) +
 Cultivator (3) 2106.84 25.50 4377.98

Disc. Harrow (2) +
 Cultivator (2) 2154.49 48.97 4643.06

Rotavator (1) +
 Chisel Plow (2) 2154.49 89.03 4772.97

Disc Harrow (1) +
 Chisel Plow (2) 2191.83 86.20 5014.57

M.B. Plow (1) +
 Disc Harrow (1) 2191.83 86.20 5014.57

 Change in Incremental
 Income over Cost Benefit
Treatment Control Ratio

Cultivator (5) -- --

Rotavator (1) +
 Cultivator (3) 196.28 1:7.70

Disc. Harrow (2) +
 Cultivator (2) 461.35 1:9.42

Rotavator (1) +
 Chisel Plow (2) 591.26 1:6.64

Disc Harrow (1) +
 Chisel Plow (2) 832.86 1:19.66

M.B. Plow (1) +
 Disc Harrow (1) 832.86 1:19.66

Source: Razzaq et al. (1993).

Table 8

Dominance Analysis of Field Trials on Sodic Soils with Pans

Treatment Cost Benefit Net Benefit

Cultivator (a) 1289 3441 2152
50 GR + Cultivator (a) 1439 3351 1912 D
50 GR + Subsoiler (b) 1836 4046 2210
50 GR + Chisel Plow (c) 1924 3602 1678 D
50 GR + Disc Plow (d) 2099 3398 1299 D
75 GR + Cultivator 1515 3534 2019 D
75 GR + Subsoiler 1912 4658 2946
75 GR + Chisel Plow 2000 4312 2312 D
75 GR + Disc Plow 2175 4117 1942 D

(a) The cultivator treatment includes cultivator (14) +
rotavator (1) + disc harrow (1).

(b) Subsoiler treatment includes subsoiler (2) + cultivation (12)
+ rotavator (1) + disc harrow (1).

(c) Chisel plow treatment includes chisel plow (2) + cultivator
(12) + rotavator (1) + disc harrow (1).

(d) Disc plow treatment includes disc plow (2) + cultivator (12) +
rotavator (1) + disc harrow (1).

D. Dominated treatment.

Table 9

Marginal Analysis of Field Trials on Sodic Soils with Pans

 Total
 Cost
 that Marginal Net Marginal
Treatment Vary Cost Benefit Benefit MRR

Option I
 Cultivator 1289 547 2152 58 10.60%
 50 GR +
 Subsoiler 1836 2210
Option II
 Cultivator 1289 623 2152 794 127.44%
 75 GR +
 Subsoiler 1912 2946

Table 10

Area Affected by Wind and Water Erosion (Thousands Hectares)

 NWFP+
Degree of Erosion Punjab Sindh FATA

Wind Erosion
Slight 2251.4 295.0 13.1
Moderate 279.1 70.2 3.8
Severe to Very Severe 1274.0 273.8 19.6
Total 3804.5 639.0 36.5
Water Erosion
Slight 61.2 -- 156.3
(Sheet and Rill Erosion)
Moderate 896.8 -- 853.8
(Sheet and Rill Erosion)
Severe (Rill, Gully &/or 588.1 58.9 1765.1
 Stream Bank Erosion)
Very Severe (Gully, Pipe 357.9 -- 1517.0
 and Pinnacle Erosion)
Total 1904.0 58.9 4292.2

Degree of Erosion Balochistan N.A. Pakistan

Wind Erosion
Slight 36.0 -- 2595.5
Moderate 143.6 -- 496.7
Severe to Very Severe 100.9 -- 1668.3
Total 280.5 -- 4760.5
Water Erosion
Slight -- 180.5 398.0
(Sheet and Rill Erosion)
Moderate 1805.0 25.8 3581.4
(Sheet and Rill Erosion)
Severe (Rill, Gully &/or 829.6 504.2 3754.9
 Stream Bank Erosion)
Very Severe (Gully, Pipe -- 1571.6 3446.5
 and Pinnacle Erosion)
Total 2634.6 2282.1 11171.8

Source: Mian and Mirza (1993).

Table 11

Index of Input, Output, and Income on Untreated and Treated
Soil Conservation Farms
 Untreated Treated
Items Farm Farm

A. Inputs
 Labour 100 252.40
 Capital 100 403.67
 Land 100 343.85
 Total Input 100 332.36
B. Yield Per Acre
 Wheat 100 223.33
 Gram 100 478.76
 Lentil 100 481.88
 Bajra 100 246.87
 Watermelon 100 246.65
C. Income Per Acre
 Gross Income from Crops 100 452.88
 Gross Income from the Whole Farm 100 714.50
 Net Income from Crops 100 201.46
D. Erosion Free Area (%) 22.78 98.78
E. Cropping Intensity (%) 32.33 118.88
F. Area under Forests and Grasses of 0 14.16
 Total Farm Area (%)

Source: Ahmad (1968).