Perception and management of farmyard manure in the semi-arid tropics of India

Agricultural Systems 46 (1994) 189-204 © 1994 Elsevier Science Limited Printed in Great Britain. All rights reserved 0308-521 X/94/$07.00 ELSEVIER

Perception and Management of Farmyard Manure in the Semi-Arid Tropics of India P. P. Motavalli Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, Colorado 80523, USA

R. P. Singh & M. M. Anders ICRISAT, Patancheru, 502 324 Andhra Pradesh, India. (Received 30 November 1992; accepted 4 October 1993)

ABSTRACT Farmyard manure ( F Y M ) is an important organic resource for agricultural production in livestock-based farming systems in the semi-arM tropics of India. However, use of F Y M has been affected by a shortfall in its supply, by increasing demand for plant nutrients, and by the increasing use of manufactured fertilizers. This study was undertaken to assess farmers' perceptions and management practices with FYM, particularly in relation to the use of manufactured fertilizers. Survey results indicated that farmers perceive F Y M to be a complement to fertilizer rather than a substitute. Partly in response to the limited availability of both fertilizer and FYM, farmers'prineipal management strategy has been to concentrate inputs on irrigated areas and important rainfed, income-generating crops. Combined applications of F Y M and fertilizer has become an increasingly common practice. However, the largest proportion of cultivated area still receives little or no soil amendments.

INTRODUCTION Use of organic soil amendments, such as farmyard manure (a heterogenous composted organic material consisting of a mixture of dung, crop residues, and/or household sweepings in varying stages of decomposition), is an important component for sustainable agricultural production 189

190

P. P. Motavalli, R. P. Singh, M. M. Anders

in many countries (Stinner & Blair, 1990; Tandon, 1990). Such amendments, when applied to agricultural land, promote sustainability because of: (1) their long-term positive effects on soil chemical and physical properties (Khaleel et al., 1981; Agboola, 1982; Lee & Wani, 1989); (2) the possibility of recycling plant nutrients within a farm [e.g. feeding harvested fodder to livestock and then applying farmyard manure (FYM) from those animals back to the land; Parker, 1990]; (3) the possible substitution of readily available organic inputs for chemical fertilizers and, therefore, a decreased dependence on external sources for costly chemical fertilizers (King, 1990); and (4) the general improvement in crop yield and quality obtained when adequate rates of organic soil amendments are incorporated into the soil (Nambiar & Abrol, 1989). In India, an estimated 2000 million tons of dung and urine are excreted annually from a total livestock population (cattle, buffalo, sheep and goats) of 430 million animals (Krishnamoorthy & Kothandaraman, 1982; Gaur et al., 1984; FAO, 1989). This livestock population represents approximately 14% of the world's total. The annual dung and urine output from livestock contains an estimated 3.2 million tons of nitrogen (N), 0.5 million tons of phosphorus (P) and 1.6 million tons of potassium (K). This equals approximately 57% of the total nutrients contained in the chemical fertilizers used in India in 1989 (Gaur et al., 1984; Agro-chemicals, 1989). Over 70% of the Indian livestock population is found in the semi-arid tropics (SAT) of India (Andhra Pradesh, Gujarat, Haryana, Karnataka, Maharashtra, Madhya Pradesh, Punjab, Rajasthan and Uttar Pradesh) where livestock-based farming systems predominate (Directorate of Economics and Statistics, 1987; Vaidyanathan, 1989). India's SAT, therefore, provides an example of the important role of an organic soil amendment in livestock-based farming systems and its possible impact on sustainable agricultural production. This study was undertaken to: (1) examine recent trends in FYM supply and use in the SAT of India; (2) assess farmers' perceptions of how FYM affects crops and soil, and its relative value in relation to manufactured fertilizers; and (3) determine differences in farmers' management practices with FYM and manufactured fertilizers as affected by farm size, access to irrigation, and crop planted.

METHODOLOGY To determine trends in FYM supply and use and to assess farmers' attitudes towards FYM, initial survey data were collected between 1975 and 1984 from 90 households, representing small, medium and large farm

Perception and management of farmyard manure in the semi-arid tropics o f India 191

holdings, in three Indian villages. The villages, located in the states of Andhra Pradesh and Maharashtra (Fig. 1), differ widely in soil type, rainfall pattern, livestock holdings and cropping systems (Table 1). The survey data included detailed information on FYM and fertilizer use practices for individual plots farmed by various households. Details of the background, methodology and results of the larger survey, conducted by the International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), of which these data are a part, can be found in Walker & Ryan (1990). Additional data were collected through follow-up surveys on 50 ranDistrict boundary .............. State boundary

-.-.-.-...-.-.-.-.:.:.~

• •

SAT boundary Districtheadquarters Survey villages

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AkolaDl~dot

;" "i": AndhraPrsd.h_ )

MshabubnsgarDlstrbt 8holapur District

...,...""

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Fig. 1. Location of three study villages in India's semi-arid tropics.

P. P. Motavalli, R. P. Singh, M. M. Anders

192

TABLE 1

Characteristics of Three Study Villages (1981-1983)

Characteristic

Village Aurepalle

603 Shallow Alfisol 760 Annual rainfall a (mm) 128 Cropping intensity (%) Irrigation b (%) 22 Post-rainy season cropping b ( % ) 23 Intercroppingb ( % ) 39 Average size of landholding (ha) 3.17 Number of cattle per household 3.6 Number of cattle per 10 ha of land 11-2 Proportion of households owning cattle (%) 51 Major crops Sorghum, castor, paddy Number of households Soil type

Shirapur

Kanzara

404 Medium to deep Vertisol 665 105 11 71 32 4.22 2.2 5.3 42 Sorghum, pigeonpea, chickpea, sunflower

240 Medium Vertisol 885 110 14 6 76 4.51 2.8 6-2 58 Cotton, sorghum, mungbean, wheat

"Averaged over 1975 to 1983. bRefers to the proportion of total cropped area.

domly selected farmers in each of two of the study villages (Aurepalle and Kanzara) in 1989 and 1990.

RESULTS AND DISCUSSION FYM supply and demand FYM supply in India is affected by: (1) changes in the number and composition of livestock; (2) efficiencies involved in collecting and storing dung; (3) the amount of additional organic material added to dung pits to produce FYM; and (4) competing uses for dung such as for fuel, construction, household cleaning and biogas production. Based on SAT data for livestock populations from 1956 to 1989 and farmers' responses regarding recent FYM management practices in the survey villages, an estimate of the amount of FYM available for crop amendment purposes was calculated for the SAT region (Fig. 2).

Perception and management of farmyard manure in the semi-arid tropics of India 193

500

350

Uvestock 325

450

300

400

"10 ¢n ¢.-

e-

._o E

"o_ ,,.<

275

350

2513

300

225

250

t°O~ "-I Q. 0 O-

"10

:::::1

o

200 1950

,

~

~

,

I 1960

,

,

,

,

I 1970

,

,

,

,

I 1980

,

,

,

,

I 1990

,

:~

200

Year Fig. 2. Growth in livestock population and FYM supply in India's SAT, 1956-89.

The equation used was:

FYM supply = [(CP * DC)+(BP * DB)] * 365 * CU * BA where: CP = cattle population, B P = buffalo population, D C = daily cattle dung collection of 3 kg day l cattle ~, DB = daily buffalo dung collection of 5 kg day -L, buffalo -L, CU = competing uses factor of 0-8, BA = bulk addition factor of 1.5 for addition of other organic materials. This estimate of supply does not take into account the large differences in FYM production between regions and changes that have taken place over time in competing uses of dung. Farmers' estimates of wet dung collected per day in the survey villages were approximately 3-4 kg per head of cattle and 3-7 kg per head of buffalo. Because of losses of dung during collection, farmers' estimates are lower than published measurements of average daily dung excretion rates of 11 and 12 kg (wet) day -L for Indian breeds of cattle and buffalo, respectively (Gaur et al., 1984). Farmers' estimates of the proportion of dung used for fuel were also relatively low, averaging 8%, compared to estimates for all of India of approximately 13-40% by weight (Gaur et al., 1984). Overall, farmers estimated that an average of 20% of the total dung collected went for competing uses other than land application. Therefore, the competing uses factor was set at 0.8 in the calculation of FYM supply. Although Fig. 2 suggests that FYM supply in the SAT of India has

194

P. P. Motavalli, R. P. Singh, M. M. Anders

increased over time, demand has generally exceeded supply because of increased cropping intensity and increased area under cultivation. A calculation of the amount of FYM available per ha of cropped land shows that FYM availability has remained constant at approximately 2 tons (wet) ha -~ since 1956. The average difference between actual FYM application rates and farmers' desired rates of application in the survey villages indicates a shortfall of 8 tons (wet) ha -~ for the 1989/90 season. Demand for plant nutrients in India has been stimulated by increasing cropping intensity, especially of irrigated land, by the increased area sown to hybrid varieties and high value income-generating crops, and by improvements in disseminating information to farmers regarding soil fertility practices (Randhawa & Abrol, 1990). Demand for FYM is also influenced by the availability and prices of manufactured fertilizer; the costs in time and money to empty, transport and spread FYM; and farmer perceptions of the comparative effects of FYM versus manufactured fertilizers. Fertilizer consumption has risen significantly within the SAT of India, but use, especially on rainfed areas, remains low compared to the overall national average. The average level of fertilizer (kg of N + P + K) applied in the SAT increased by 126% during 1971 to 1983 (Singh & Desai, ICRISAT, 1990, pers. comm.). Average fertilizer (kg of N + P205 + K20) consumption in India was 62 kg ha -1 in 1988/89, but rainfed areas received an average of only 10 kg ha -~ (Agro-chemicals, 1989). The risk of investing in fertilizer inputs under conditions of climatic uncertainty constrains increased fertilizer use (Babu et al., 1991). Additionally, crop response to added plant nutrients under conditions of moisture stress is often limited. Therefore, approximately two-thirds of all the cropped area within the SAT receives no fertilizer inputs (Singh & Desai, ICRISAT, 1990, pers comm.).

Farmers' perceptions Relationships between FYM and fertilizer use depend partly on farmers' perceptions of the effects of the two materials on soil properties and crop growth. Increasing evidence indicates that farmers in the SAT of India perceive fertilizer and FYM to be complements rather than substitutes (Singh & Desai, 1991). Such perceptions eventually influence farmers' management of FYM and their application decisions. The most common response from farmers in the study villages of Aurepalle (Alfisol, unassured rainfall village) and Kanzara (Vertisol, assured rainfall village) referred to the beneficial physical effects on soil of FYM (Table 2). Improved moisture retention and a 'loosening' of soil

Perception and management of farmyard manure in the semi-arid tropics of India 195

TABLE 2 Farmers' Perceptions of Effects of FYM Applications on Soil and Crop Growth in Aurepalle and Kanzara Villages Perceived effects

Village Aurepalle

Kanzara

Percentage of total responses~ Soil: Loosening of soil Increase in water-holding capacity Less soil cracking Less crust formation Increased soil fertility Maintenance of quality of land Crop growth: Improved crop growth Increased grain yield and quality Better seed germination and crop stand Induction of tillering Protection of crop from diseases and weeds Development of better root system Faster crop maturity Increased weed population Crops get burnt with low rainfall

30 29 --

45 19 8

6 15 20

28 --

--

61

33 32 21 9 4

17

1 --

13

--

9

n -- 50 farmers from each village. were among the responses most often mentioned, despite the difference in predominant soil type between the two villages. Farmers often explained that the chief advantage of this soil loosening with F Y M was the resultant decrease in bullock power requirements at the beginning of the rainy season. Improvements in soil fertility were also perceived, but to a lesser extent than physical effects on soil condition. In Aurepalle, the second most c o m m o n response (20% o f all responses) was that land quality was maintained with additions of F Y M . Frequently, long-term fertility effects of F Y M applications were mentioned in contrast to the perceived shortterm effects of inorganic fertilizer applications. The most c o m m o n l y cited F Y M effect on crop growth (33% of all responses in Aurepalle and 17% in Kanzara) was that F Y M improves the formation, quality and size o f grain (Table 2). Farmers in both villages also observed improved crop stands and crop growth w i t h the use o f F Y M . However, in Kanzara, detrimental effects o f F Y M , including increased weed populations (13% of responses) and crop burning in association with low rainfall (9%) were also mentioned.

196

P. P. Motavalli, R. P. Singh, M. M. Anders

TABLE 3 Farmers' Perception of Major Crops that Respond more to either FYM or Fertilizer Applications Village

Respond more to F Y M

Respond more to fertilizer

Aurepalle

Castor, cotton, pigeonpea, safflower

Vegetables, local pearl millet, sorghum, chillies

Kanzara

Hybrid cotton, groundnut, sugarcane, mung bean

Sorghum, wheat

Farmers also perceived a difference between crop response to FYM and inorganic fertilizer (Table 3). Generally, the major income-generating crops of the village were perceived as responding more to FYM and the principal cereal crops as responding more to fertilizer. In addition, residual effects of FYM on crop growth were perceived to be longer (an average over all villages of three growing seasons) than for manufactured fertilizer (an average of one growing season).

Management practices Rainfed and irrigated areas With the exception of Shirapur, where low and erratic rainfall affects the recharge capacity of irrigation wells, there was an increase in irrigated area between 1975 and 1984 in the survey villages. The proportion of total cropped area irrigated increased from 17 to 26% in Aurepalle and from 2 to 20% in Kanzara during that period. The proportion of irrigated area in Shirapur was 17% in 1975 and 14% in 1984. In all three villages, a larger proportion of irrigated area was fertilized compared to rainfed areas (Fig. 3). For Aurepalle, Shirapur, and Kanzara, the proportion of irrigated area that was manured over the 10year period averaged 34% +11%, 22% +14% and 21% +12%, respectively. In comparison, the proportion of rainfed areas manured over the same period was 25% +7%, 6% +5% and 15% +7%, respectively. However, increasing proportions of the rainfed area in both Aurepalle and Kanzara were fertilized after 1980, mostly because of the introduction of new castor varieties in Aurepalle and hybrid sorghum in Kanzara. Average application rates of FYM and fertilizer tended to be higher on irrigated areas compared to rainfed areas, but there was a consider-

Perception and management of farmyard manure in the semi-arid tropics of India 100

Aurepalle ,.,.,""--. ....... ",.

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197

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75

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75 RolMed /

50 25 1974

i

J

1976

1978

,

i

1980 Year

,

i

1982

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i

1984

1986

Fig. 3. The proportion o f cultivated areas that were fertilized in the study villages.

able amount o f annual variability in F Y M rates (Fig. 4). Only Aurepalle had a clear trend of increasing F Y M rates over time on irrigated land. Irrigated areas also received F Y M more frequently than rainfed areas. For example, as of 1989, F Y M was more commonly applied once every 3-6 years to rainfed areas and twice-yearly, once-yearly or once in every 2 years to irrigated areas in Aurepalle (Fig. 5). Farm size In all three survey villages, large farms (farm size classes for each village were for Aurepalle: small -- 0.2-1.2 ha, medium = 1.2 3.2, large = > 3.2; for Shirapur: small = 0.2-2.0 ha, medium = 2.0-5.3, large -- > 5.3; and for Kanzara: small -- 0.2-1.8 ha, medium = 1-8-5.3 large -- > 5.3) had the highest proportion o f cropped land and used most of the total fertilizer and F Y M applied in each year (Fig. 6). Such farms tended to have more resources to purchase fertilizer and also a larger F Y M supply from bigger livestock holdings compared to those o f small farms. However, small farms tended to rely more on F Y M (9% of total F Y M applied) than

P. P. Motavalli, R. P. Singh, M. M. Anders

198

Fertilizer

150 125

FYM

20

Rainfed areas

Rainfed areas

Aurepall. e S.hi.rapur

11111

15

Kanzara A

..~ 75

10

® 25 o

o

._N_150

t

Irrigated areas 125 \..

100

'%

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%

/-"

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i

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i

i

I

i

Irrigated areas

%.

75

10

50 5

25 0

i

i

i

i

i

1974 1976 1978 1980 1982 1984 1986 Year

O 1974

i

L

1976

1978

i

1980

I

1982

i

1984

1986

Year

Fig. 4. Fertilizer and F Y M application rates for rainfed and irrigated areas in the three study villages, 1975-84. Rates are calculated on the basis of area fertilized or manured and not on total area.

50 A

17/] Ralnfed

o<

[]

" " 40

Irrigated

G2 "O 4) q-

CD

.E b

o c

2O

.o_ 1:: O

D. 10

o

O.

Twicea-year

Oncei-y~r

Onoe wery 2 years

O n o e every 3 years

Or~e every 4 yurl

Once evmy S years

Once evmy is y u r l

,m~d

Frequency of application Fig. 5. Frequency of F Y M applications to rainfed or irrigated cropped land in Aurepalle village.

Perception and management of farmyard manure in the semi-arid tropics of India 199 Cropped area 21% Farm size [ ] Small

10%

[ ] Medium BE Large

FYM

Fertilizer

28% 9% 3%

? 03'7o

Fig. 6. Proportion of the total cultivated area and fertilizer or FYM applied to different farm size categories averaged over the study villages, 1982-84 average.

fertilizer (3% of total fertilizer applied) as a nutrient source relative to large farms. Only the village of Kanzara had a similar distribution of total fertilizer and FYM for small, medium and large farms (data not shown).

Crops A comparison of the proportion of area planted to different crops in the three study villages showed little change from the period of 1975-77 to 1981-83, except for the increase in area planted to hybrid sorghum (Fig. 7). Sorghum (hybrid and local varieties), cotton, pulses, paddy rice, castor and groundnut accounted for the largest proportion of area planted. The largest proportion of fertilizer was applied to cereals such as paddy rice, sorghum and wheat, and to important income-generating crops such as cotton and castor. Cotton also received the highest share of FYM while castor and local sorghum received a relatively higher proportion of total FYM compared to fertilizer. Crop rotation is a common practice in these villages. Since FYM supply is limited, farmers often apply higher rates of FYM to the most important crop in the rotation and allow the subsequent crop to rely on the residual effects of the initial FYM application. In Aurepalle, for example, a rotation of castor, which commonly receives FYM, succeeded by sorghum, which receives little or no FYM, is often followed in dryland

200

P. P. MotavallL R. P. Singh, M. M. Anders

1978-77

1981 4 3 Share In cropped area

s ~

::::

•"' ".:.:.s:.::.%.:.:.:.:.:.::

Share In FYM u l l Cotm,n

Socg~um ( 1 " 0

~ ~ h u m

Pul

~

u

m

(L) ~i~ad~hum

================================================

(tO

(t~ ..... ...v..,:.:.:.:.::::::::::i:i:i:!:

Share In NPK use PulI

Gn~u~

V~rm~t~

Fig. 7. Average share of important crops in total cropped area and average FYM and fertilizer use in the three study villages during 1975-77 and 1981-83. L and H refer to local and hybrid varieties, respectively.

areas. In Kanzara, the cotton grown during the rainy season often receives FYM while the subsequent crops, such as wheat or groundnut grown with irrigation during the post-rainy season, do not receive FYM.

Crop yields Long-term field trials containing both separate and combined treatments of fertilizer and FYM have been carried out in India for a variety of crops and soil types for approximately 100 years (Nambiar & Abrol, 1989). Results of such trials have indicated the long-term yield benefits

Perception and management of farmyard manure in the semi-arM tropics of India 201

lOO

Auropallo 75 50 25 o

~-- loo

~ Ts

25 0 100 KJnzara

75 50 25 0

Fertilizer

FYM

Both

None

Soil amendment

Fig. 8. Proportion of cropped area in the study villages which received either fertilizer alone, FYM alone, fertilizer and FYM, or no soil amendment averaged for two periods, 1975-77 and 1981-83.

from combining organic and inorganic soil amendments. These benefits have been attributed largely to effects on the maintenance of soil organic matter and balanced fertilization under intensive cultivation. The proportion of cropped area, in which both fertilizer and FYM were applied, increased in Aurepalle and Kanzara during 1975-77 to 1981-83 (Fig. 8). However, it remained a relatively small proportion of the total cropped area compared to the proportion of area in which no soil amendments were applied. Examination of comparative yields at two time periods in the study villages for local and improved varieties of paddy rice and sorghum, showed that, in general, combining fertilizer and FYM (M + F) resulted in higher yields compared to when fertilizer (UM-F) or FYM (M-UF) was applied alone or when there was no soil amendment (UM-UF) (Fig. 9). Contributing to the observed yield differences were also differences in farmers' management, irrigation and other inputs that may coincide with

202

P. P. Motavalli, R. P. Singh, M. M. Anders

5.0

Sorghum ( L o c a l )

Sorghum (Hybrid)

Paddy Rice ( L o c a l )

Paddy Rice (Hybrid)

4.0 3.0 •o J>.

2.0 1.0

5.0 4.0 3.0

2.0 1.0 1975-77

1962-84

Year

1975-77

Year

41

Fig. 9. Average yields of local and hybrid varieties of sorghum and paddy rice in the three study villages during the periods 1975-77 and 1982-84. UM-UF = unmanured and unfertilized; UM-F -- unmanured and fertilized, and M + F = manured and fertilized. or determine certain types of fertility practices. For example, more productive irrigated land was more likely to receive combined fertilizer and F Y M applications than less productive rainfed land. In general, adding fertilizer alone also increased yields compared to unfertilized and unmanured plots, but yield increases for areas receiving F Y M alone were more important for local varieties of sorghum and paddy rice (Fig. 9). The practice of applying F Y M alone also diminished over the 10-year period, especially for high yielding and hybrid varieties.

SUMMARY AND CONCLUSIONS Use of FYM is an integral part of livestock-based farming systems in the Indian SAT. Despite increasing use of manufactured fertilizers and shortfall in F Y M supply in the SAT region, F Y M has remained a major fertility resource for farmers, particularly for farmers with smaller land holdings. Farmers' perceptions of F Y M effects differ greatly from their perceptions of the effects of manufactured fertilizer. Improvement of soil physical properties and residual effects in the soil were among the most c o m m o n perceptions of FYM. This may indicate that farmers perceive F Y M as a complement to fertilizer rather than as a substitute.

Perception and management of farmyard manure in the semi-arid tropics of India 203

Since F Y M and fertilizer are often limited resources, farmers' basic management strategy has been to concentrate inputs on irrigated areas and important rainfed, income-generating crops. Such a strategy is also reflected in the greater frequency of F Y M applications on irrigated areas. Combined use of F Y M and fertilizer has also increased. As evidenced by long-term trials, combined use of F Y M and fertilizer is also a more sustainable agricultural practice for maintaining soil fertility. However, if current trends continue, organic plant nutrients from F Y M will continue to provide a decreasing proportion of the total nutrients applied for agricultural production in India. Moreover, the limited supply of F Y M and the risk involved in fertilizer use in rainfed areas constrain wider use of these two sources of plant nutrients. Research efforts and Government programs aimed at improving the efficiency of F Y M production and use, and reducing risks associated with applying fertility inputs on rainfed areas in the Indian SAT, could aid in promoting integrated management of available soil fertility resources, an important step in a region where most of the cultivated land receives little or no soil amendments.

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