thailand; recycling of wastewater from pig farms in urbanperi-urban agriculture

8/3/2019 Thailand; Recycling of Wastewater from Pig Farms in Urbanperi-urban Agriculture

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Recycling of Wastewater from Pig Farms

in Urban and Peri-Urban Agriculture

SUPAMARD PANICHSAKPATANA


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Recycling of Wastewater from Pig Farms

in Urban and Peri-urban Agriculture

Supamard Panichsakpatana

ABSTRACT

Urbanisation is the main cause of change in cropping pattern in the Central

part of Thailand. The provinces where farm lands occupy on more than 15%, such as

Bangkok and Samut Prakarn, land use is changing from the rice paddy to ornament

plants and vegetables. In the areas where agricultural land exceed 50% of the total

land area, like Chachoensao and Nakhon Pathom, most of the farm lands are

vegetables and orchards besides rice fields.

In peri-urban area, the main agricultural activities turn to be livestock

production and aquaculture. Most of the livestock here are monogastrics especially

pig and poultry since they are not roughage dependants and more efficient in feed

conversion. The serious problems in this case turn to be the wastes and the

wastewater from farm lands and their contamination of nitrate and salinity to the

surface and the ground water.

Management of the wastewater as fertilizer and fertigation was presented in

this paper. The wastewater could replace chemical fertilizers as much as 80-100% of

the application rate depending on type of growing crops. For example, it could

replace up to 100% of the chemical fertilizers at the recommended rate of the

chemical N for corn, sweet corn, Guinea grass (Panicum maximum Jacq), sugar cane,

and cassava at 62.5, 93.75, 156, 93.75, and 112.5 kg N.ha-1, respectively. Better yield

and nutrients of the crops were generally observed in the combination treatment of

the half dose of the chemical N + the wastewater. In vegetable, such as Chinese

green mustard (Brassica campetris ssp chinensis var parachinensis (Bailey) and/orPak-choy, (Brassica campetris var chinensis), application of the wastewater could

give the yield 80-100% as much as those treated with chemical N.

Application of the concentrate wastewater could replace some amount of

water consumption of the crops. For instance, the wastewater at the above


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recommended rate could replace the irrigation water as much as 220,000 to 440,000,

187,500 to 375,000 and 380,000 to 760,000 litres.ha-1

in one season of corn, Chinese

green mustard and sugar cane respectively. Fertigation of the crops could be done

for the whole season by mixing the wastewater with the irrigation water to reach the

concentration about 100 mgN.L-1

.

At the above recommended rate, there was no evidence of nitrate

contamination in the ground water. There was no evidence of zinc and copper

accumulation in the tested crops and in the soils though the treated soils were very

sandy in texture and the ground water level was shallow. There were high amount of

coliform bacteria (540,000 MPN.100 ml-1

) and E. Coli (1.2 x 103

CFU.ml-1

) in the

wastewater. Hookworms and threadworms (Strongyloides stercoralis) were found in

both soils treated and untreated with the wastewater but they were not found in the

treated crops.

Keywords: wastewater, urban and peri-urban agriculture, nitrate contamination,

fertigation, pig farm, water pollution

RECENT CHANGES IN CROPPING PATTERN

AND LIVESTOCK PRODUCTION

Urban Agriculture

The big cities with the population over 1 million have been increased rapidly

during the last decades resulting in increasing of food production in the area. With

this phenomenon, great impacts on natural resources, especially land and water, have

been occurred. According to UN World Water Development Report, water quality is

declining in most global regions. The problem is obvious in urban and peri-urban

areas where half of the world population will be living in by 2007. By 2030, towns

and cities will have risen to nearly two thirds, resulting in drastic increases in water

demand in the areas.

When rural areas turn into towns, agricultural patterns have been gradually

changed into urban and peri-urban agriculture (UPA). The rice field decreases in

proportion with the population density. The land has been used with more mixed

crops instead of the rice monoculture. High valued cropping such as ornamental

planting is replacing the rice planting. Vegetable fields and orchards are replacing

rice fields as well. For example in Bangkok plain during the year 1989 to 1995,

vegetable areas increased by more than 35% when fruit trees increased by about 20%


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whereas paddy lands decreased by 2.7% and sugarcane by 3.4% (Saridnirun and

Pages, 1999). The effect of urbanisation on the farm land is illustrated in Table 1 and

2 and Fig. 1. Bangkok and its vicinity comprise 7 provinces. Bangkok and Samut

Prakarn are the most crowded areas. Population density in the areas exceeds 1,000

persons.km-2

(Table 2) resulting in the farm land occupies no more than 15% of the

total land areas. These provinces focus the agricultural field into ornamental plants

and vegetables (Table 3). In the areas where agricultural land exceeds 50% likeChachoengsao and Nakhon Pathom, most of the farm lands are vegetables and

orchards besides the rice field.

Table 1 Land use in urban agriculture

ProvincesTotal area

(ha)

Agricultural area

(ha)

Ratio

Agric/Total

Chachoengsao 237,042 205,352 0.87

Nakhon Pathom 221,009 111,864 0.51

Nonthaburi 142,715 31,384 0.22

Pathumthani 150,224 68,884 0.46

Bangkok 156,609 21,276 0.14

Samut Prakarn 97,042 8,614 0.09

Samut Sakhorn 86,355 22,500 0.26

Source: Ministry of Agriculture and Cooperative, 1998

Table 2 : Population density in Bangkok and vicinity

ProvincesTotal area

(ha)Population

density

ind/km

Chachoengsao 237,042 632,533 266.8

Nakhon Pathom 221,009 809,062 366.1

Nonthaburi 142,715 810,254 567.7

Pathumthani 150,224 690,402 453.6

Bangkok 156,609 6,320,174 4,035.6

Samut Prakarn 97,042 1,014,449 1,045.4Samut Sakhorn 86,355 457,078 529.3

Source: National Census 2000


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Calculation was based on data from Table 1 VS Table 2.

Figure 1 Relationship between population density and ratio of the farm land.

Table 3 Comparative crops area at provincial level (1998)

% area Rice Vegetables fruits perennial ornamentals

Chachoengsao 38 7 31 54 1

Nakhon Pathom 24 51 23 11 39

Nonthaburi 8 11 7 2 19

Pathumthani 19 12 19 1 1

Samut Prakarn 2 12 7 17 -

Samut Sakhorn 1 3 9 13 15

Bangkok 8 4 3 1 25

Total area (ha) 480,307 20,401 96,115 39,119 5, 014

Source: Chunnasit et al., 2000

Peri-urban Agriculture

In urban agriculture, excess of nutrients (especially N and P) are considerably

less since the main nutrient loss will occur only by way of discarding the agricultural

wastes. In fact, many portions of wastes are recycled through various means. For

example, vegetable wastes will be used for animal feeding. Some may be used for

composting. However, there are much nutrients imported into the system. For

example, vegetable production in this area covers 2,500 ha. With this amount of

production, the amount of 250, 250, and 300 t.year

-1

of the nutrients N, P2O5, and K2Oin the form of chemical fertilizers are imported to the system, respectively. Besides

the chemical fertilizers, 3,000 t of duck waste, 500 t of peanut residue, and over 1,000

t of farm compost are incorporated into the crop production as well (Duangngam and

Pages, 2000). By the loss of these nutrients, the ground and the surface waters in the

area might be contaminated with N, P, and the pesticides using in the vegetable

production.

-0.200.400.600.801.00

- 1,000.

0

2,000.

0

3,000.

0

4,000.

0

5,000.

0

population density (ind/km 2)

ratio

of

agriculturalland


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Peri-urban agriculture has another scenario. In peri-urban area, the main

agricultural activities turn to be livestock production and aquaculture. Most of the

livestock here are monogastrics especially pig and poultry since they are not roughage

dependants and more efficient in feed conversion. To profit from economies of scale

and to be near the market for their perishable products, the new pig and poultry

production is often based on large industrialised units close to urban agglomerations.

These units often have not enough knowledge to manage the livestock excreta on theirown farm. It therefore has to be discharged directly to water courses or is lost through

non-existing or insufficient handling facilities (leaching, run-off, overflow of lagoons

etc.) which results in a high pressure to the environment. The serious problems in this

case turn to be the wastes and the wastewater from farm land and their contamination

of nitrate and salinity to the surface and the ground water.

UPA such as aquaculture and livestock production produce large amount of

wastewater that becomes the major sources of water contamination since livestock

excretes 70 to over 90% of the nutrient N, P, K and heavy metals taken up in the feed.

For instance Thachin River, less than 50 km from Bangkok, an affluent tributary of

Chao Phraya River, was ranked the most polluted river in Thailand from the year

2000 to 2002. This was caused by the wastewaters from pig farms and industrial

plants.

WASTEWATER MANAGEMENT

IN URBAN AND PERI-URBAN AGRICULTURE

Wastewater from stationary ponds

The author set the experiments for investigating wastewater management in

Chol Buri and Rayong provinces located around 100-150 km east of Bangkok. Thesites were situated in Bang Pakong River Basin where the production of pig, poultry

and fish are accounted for 25%, 32% and 58% of the total production in Thailand,

respectively (Panichsakpatana, 2003). Since the area is under the export promotion

program by the Thai Government, it can be expected that the pig production will rise

sharply and may reach two folds of the present figure in the next 10 years. At present,

the excessive populations of the livestock make the overloads of N (264%), P (413%)

and K (279%) in some districts of the region. The contamination of the wastewater in

Bang Pakong River has already occurred in some regions. Since Cu and Zn are used

as food additives for pigs, the two elements might contaminate to the soil and the river

as well (Harada et al., 1993).

The soil in PK farm in Chol Buri province was Sathon series (Stn): fine-loamy, mixed, semiactive, isohyperthermic Typic Plinthaquults. The soil in NR farm

in Rayong province was classified as Chalong, coarse loamy variant (Chl-co): coarse-

loamy, kaolinitic, isohyperthermic Typic Kandiudults.

The wastewater from the PK farm was from the pregnant sows whereas that

from the NR farm was from the fatteners. The analysis of the wastewater using in this

trial was as follows: -


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Total N NH4-N NO3-N

(mg.L-1

)

PK farm 209-385 (297) 165-230 (189) 0-3.5 (2)

NR farm 175-385 (228) 150-210 (180) 0-4.2 (2)

The figures in the parentheses were the average values for the correspondingitems. With the estimation from the mean values, the wastewater from the pregnant

sows contained 65% inorganic-N whereas that from the fatteners contained the

inorganic-N as much as 80% of the total-N.

Five kinds of crop namely cereal, sugar, vegetable, oil and tuber crops were

chosen for the field experiments. They were corn, sugar cane, Chinese green mustard

(Brassica campetris ssp chinensis var parachinensis (Bailey), (CGM), oil palm and

cassava. Corn, sugar cane and Chinese green mustard were planted in PK farm

whereas oil palm and cassava were planted in NR farm.

All the experiments except that of oil palm were conducted in Randomized

Complete Block Design (RCBD) with 4 replications. There were 6 treatments for

testing of corn and sugar cane and 5 treatments for Chinese green mustard. The

treatments were as follows:

T1 : no chemical fertilizer, no wastewater

T2 : Nitrogen fertilizer

T3 : Chemical fertilizer N-P-K

T4 : Wastewater, low rate, WWL: (using Total-N for calculation with T2 rate)

T5 : Wastewater, high rate, WWH: (double rate of T4)

T6 : Wastewater + Chemical fertilizer (T4 + 1/2T3)

The N rate used in T2 and the chemical rate in T3 were the ratesrecommended by the Department of Agricultural Extension, The Ministry of

Agriculture and Cooperatives. There was no sole treatment of nitrogen fertilizer in

the experiment of Chinese green mustard.

The experiments in the pregnant sows farm

1. Nitrogen mineralization of the wastewater in the soils

The laboratory experiment was conducted to test N mineralization of the waste

water. Urea was used as the standard treatment. It was found that the wastewater

showed its benefit better than urea (Fig.2). The NH4-N from the wastewater was

available immediately after applying it to the soil whereas no available N was

observed at the day of urea application (67.2 VS 33.6 mg N. kg-1

). Nitrification in the

soil receiving the wastewater occurred after 3 days of applying the wastewater. At the

later period, mineralization of urea and the wastewater appeared in the same manner

of its rate and magnitude. The wastewater supplied nitrogen to the soil more or less

the same amount and as fast as the urea did. Regardless to its harmful effects, it could

be used as the liquid fertilizer in this case.


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2. The efficiency of wastewater as the fertilizer for crops

The rates of chemical fertilizers and wastewater were shown in Table 4. There

was no N-fertilizer treatment in the CGM experiment. In the wastewater treatments,

calculation of the application rates was based on the rate of N-fertilizer and the total N

content in the wastewater. It was then designed as the wastewater at low rate (WWL)

since the total N could gave the inorganic N only 65 to 80% according to thepreviously analytical results. The rate of wastewater in the WWH treatment was 2 x

WWL since the fertilizer application in the recommended rate was still low for the

optimum growth of the crops.

Table 4 Fertilizer rates (kgN.rai-1

) using in the experiments

Treatments Corn Vegetable (CGM) Sugar cane

N-fertilizer 10 - 15

Chem. N-P-K 10-5-5 12-8-8 15-15-15

WWL 10 12 15

Note: 6.25 rai = 1 hectare

The effects of wastewater and chemical fertilizer on the crop yields were

clearly observed in the corn experiment (Table 5). With the application of chemical

fertilizer, either N alone or N-P-K, the plants could produce the yield significantly

higher than those grown with no treatment. Application of wastewater at low rate was

found to enhance the corn yield slightly. When the plants received the wastewater at

the higher rate, they gave the yield significantly higher than those grown in the

control plot. With combination of chemical fertilizer and the wastewater, the plants

could gave the seed yield as much as 1,109 kg.rai-1

comparing to 744 kg.rai-1

of those

with no application of the fertilizer and the wastewater. There was no significantly

difference in yield among the fertilizer treatment and the wastewater treatments.

Table 5 Yield of the crops growing in PK farm in Chol Buri (year 2002)

Treatments Corn Vegetables (CGM) Sugar cane

(kg.rai-1

) (kg fresh wt/8x8m2

plot) (kg.rai-1

)

Control 744 b 24.70 b 17,432 a

N-fertilizer 973 a - 20,075 a

N-P-K 997 a 39.18 a 19,292 a

WWL 910 ab 31.91 ab 18,108 a

WWH 957 a 33.23 a 19,331 a

WWL+1/2(N-P-K) 1,109 a 37.51 a 20,210 a

CV (%) 13.5 14.4 9.4

F-test * * ns



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In the vegetable experiment, the yield of Chinese green mustard was 24.7 kg

in the control plot (Table 5). With the wastewater application, the plant yield

significantly increased to 32 33 kg. The figures might not be different much in

statistic but it would cost some considerably value for the farmers income in the

sense that more value could be obtained from the increased yield with less wastewater

to be managed. With the chemical N-P-K application, the plant yield could reach 39

kg. In other words, the wastewater enhanced the plant growth and yield as effectiveas 82 to 84% of the chemical fertilizer at the treated rates.

Since the land for planting sugar cane was applied with fertilizers before, the

effect of the treatments on the cane yield was not clearly observed in the first planting

season. Regardless to the statistical difference, application of the wastewater could

increase the sugar cane yield as much as 0.7 to 1 ton per rai (4.3 to 6.3 ton per

hectare). Application of less chemical fertilizer together with the wastewater, could

get the yield increase as much as nearly 3 ton per rai (18.8 ton per hectare). Better

response of the crop to the wastewater is expected in the next ratooning season.

The experiments in the fatteners farm

The wastewater from pig farms could be used as nutrient source for oil palms.

It released the inorganic N as the same time and amount as that of urea. It could

replace chemical fertilizer as much as 0.5-0.3-0.9 kg N-P2O5-K2O.plant-1

year-1

.

With this rate of application, the oil palm in the wastewater treated plots could uptake

the plant nutrients such as N, P, K, Mg, Cu and Zn the same amount as those in the

chemical fertilizer treated ones. Furthermore, the oil palm could produce its oil

content as high as when it received the chemical fertilizer (Table 6).

The wastewater supplied nutrients for cassava as much as the chemical N-P-K

at the rate of 18 - 7.5 7.5 kg N P2O5 K2O.rai-1

. The advantage of the wastewater

was that it could produce starch slightly higher than the chemical fertilizer could.With combination of the wastewater and the chemical fertilizer, the above ground

portion of cassava became very healthy comparing to the control one (Table 7)

Figure 2 N-mineralization of the wastewater in PK farm

32.2

14

0

67.259.5

10.5

0

14

010.5

66.5

33.6

0

20

40

60

80

0 3 7 14

Days of Incubation

NH+4(m

gN.kg-

1)

Control Wastewater Urea


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Contamination of NO3, Cu, Zn and human pathogen

In order to analyze NO3-N, the ground water was collected a week after every

application of the wastewater in the experimental fields. For tracing the harmful

effects of Cu and Zn, the wastewater, the soils and the crops were collected andanalyzed. The results showed that there was no nitrate contamination in the ground

water at the application rate of the wastewater (Figure 3). The contents of Cu, Zn and

NO3-N in the crops treated with the wastewater were not higher than that treated with

the chemical fertilizers. There were high amount of coliform bacteria (540,000

MPN.100 mL-1) and E. coli (1.2 x 103

CFU.mL-1) in the wastewater. Human

parasites were not found in the wastewater and in Chinese green mustard. The

hookworms and the threadworms (Strongyloides stercoralis) were found in both soils

treated and untreated with the wastewater.

Table 6 Yield of oil palm (gm.plant-1) (first year)

Rate of wastewaterChemical fertilizers

Low (M1) High (M2)

Mean

S1 : none 16,495.7 a 14,130.9 a 15,313.3 a

S2 : N-P-K 12,185.9 a 7,839.9 a 10,012.9 b

S3 : K 13,358.9 a 11,746.0 a 12,552.4 ab

Mean 14,013.5 a 11,239.0 a

CV(%) (M) 24.5 F-Test (M) nsCV(%) (S) 20.7 F-Test (S) **

F-Test S x M ns

N-P-K (without wastewater) 14,769.3

Control 8,975.0

(second year)

N-mineralization of the wastewater in PK farm

4235

56 54.2

98105

112

49

42

108.5

45.545.5

0

10

20

30

40

5060

70

80

90

100

110

120

0 3 7 14

Days of Incubation

NO- 3(mgN.

kg.-1

)

C ontrol Wastewater Urea


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Rate of wastewaterChemical fertilizers

Low (M1) High (M2)

Mean

S1 : none 18,611.5 a 29,230.2 a 23,920.8 a

S2 : N-P-K 22,838.3 a 19,479.4 b 21,158.8 a

S3 : K 22,690.3 a 24,968.6 ab 23,829.5 a

Mean 21,380.1 a 24,559.4 a

CV(%) (M) 27.9 F-Test (M) ns

CV(%) (S) 20.2 F-Test (S) ns

F-Test M x S *

N-P-K (without wastewater) 21,059.7

Control 15,596.0

Note: 1. The experiment was set as Split plot design (M = main plot; S = sub-plot)

2. Means in any one column not followed by a common letter are significantly different at

0.05 probability


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EC of groundwater

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Times

dS.m-

Control

M2S1

M2S3

Fert.

canal

Ammonium-N in groundwater

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Times

mgNH4-N.

Control

M2S1

M2S3

Fert.

canal

Nitrate-N in groundwater

0.00

1.00

2.00

3.00

4.00

5.00

6.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Times

mgNO3-N.

Control

M2S1

M2S3

Fert.

canal


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Figure 3 EC and the contents of ammonium and nitrate in ground water

Table 7 Growth and yield of cassava

Treatments Root weight %starch stem+leaf weight

(kg.rai-1

)

(kg.rai-1

)

T1 : control 4,157b 24.5a 617a

T2 : Chem fertilizer N-P-K 6,064a 20.5a 633a(18-7.5-7.5 kg N-P2O5-K2O.rai

-1)

T3 : Chem fertilizer N-P-K 4,834b 23.0a 661a(12-6-12 kgN-P2O5-K2O.rai

-1)

T4 : WWL 5,030ab 23.3a 593a

T5 : WWH 5,225ab 22.5a 674a

T6 : (T4 + 1/2 T3) 5,209ab 22.6a 731a

CV (%) 14.0 7.4 14.2

F-Test * ns ns


Means in any one column not followed by a common letter are significantly different at 0.05

probability

Wastewater from biogas production

Biogas production from animal wastes is quite common in temperate countries

since it can be used to produce heat or electricity during winter. In tropical countries

like Thailand, not so many animal farms adopt the biogas production. This might be

because of the high cost of biogas plant. Normally, the effluent from biogasproduction (EFB) contains fewer nutrients than the wastewater from the stationary

ponds. In the author experiments, it chemical properties (in average) were pH 7.5, EC

1.6 mS.cm-1

, BOD 23 mg.L-1

. The contents of total N, total P, total K, total Mg, total

Ca, total Na, total Zn, and total Cu were 68-98, 21, 50, 23, 20, 60, 0.1, and 0.1

mgN.L-1

, respectively. Judging from its chemical properties and nutrient contents,

EFB could be the good source of N and K for crop production.

The EFB could produce crop yield equivalent to 156 and 93.75 kg N.ha-1

of

chemical fertilizer for Guinea grass and sweet corn, respectively (Fig. 4 and Table 8).

In case of vegetable, the yield of Pak-choy in EFB plot was equivalent to 85% of that

in the (125 kg N.ha-1

) CF plot where as the EFB + CF could produce crop yield

comparable to that produced by the CF. (Fig. 5).


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Control

EFB

1/2E

FB+1/2CF

CF

1st crop

2nd crop

3rd crop

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

kg.ra

Figure 4 Yield of Guinea grass

1st crop

2nd crop

3rd crop

Source: Panichsakpatana (1995a)

Control

EFB

1/2EFB

+1/2CF

CF

1st crop

2nd crop

3rd crop

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

kg.rai

Figure 5 Yield of Pak-choy (Brassica campetris var chinensis)

1st crop

2nd crop

3rd crop

Source: Panichsakpatana (1995c)


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Table 8 Ear size and sugar content of sweet corn

Treatments Ear circumference

(cm)

Ear length

(cm)

Sugar content

(brix)

Control 12.63b 20.23 14.78

Chem Fert (CF) 13.73a 19.90 15.25

Eff. Biogas (EFB) 13.76a 21.41 15.28

EFB+ CF 13.22ab 20.59 15.42

F-test * ns ns

% CV 3.37 5.80 2.16

Source: Panichsakpatana (1995b)

Means in any one column not followed by a common letter are significantly different at

0.05 probability

The wastewater as fertilizer and irrigation water

In the pig production areas, wastewater from the pig farms is the main source

of water pollution. Bang Pakong river near Chol Buri (CBR) province and Tachin

river near Kamphaeng Saen (KPS) district are heavily polluted with the wastewaterfrom the pig farms. In order to reduce the BOD in the wastewater, many pig farms in

Kamphaeng Saen, Nakhon Pathom province produce biogas from the wastewater.

The effluent from the biogas production contained total N in the range of 68-98 mg

N.L-1

with BOD of 25 mg.L-1

. With the low content of nitrogen in the wastewater of

the biogas case, the wastewater could substitute irrigation water for the whole

planting period of Guinea grass and vegetable (Pak-choy, Brassica campestris var

chinensis) whereas it could replace irrigation water as much as 175,000 L.ha-1

. week-1

in planting sweet corn, or 1,225,000 L.ha-1

in one growing season (Table 9).

The wastewater from the stationary ponds contained total N higher than that

from the EFB. Its concentration was in the range of 175-385 mgN.L-1

(with the

average of 228 and 297 mgN.L-1

). With high N content in the wastewater, the amountof the wastewater applied for corn and vegetable was about one third of that from the

biogas production applied for the corresponding crops.

With the results from these experiments, it could be recommended that

fertigation could be done for the whole season of the crops by mixing the wastewater

with the irrigation water to have the concentration about 100 mgN.L-1

.


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Table 9 Amount of wastewater used in one season of the crops (x1,000 L.ha-1

)

Treatments Corn Vegetables Sugar cane/Grass Remarks

CBR KPS CBR KPS CBR KPS

WWL 220 - 187.5 - 380* - *sugar cane

WWH 440 1,225 375 1,225 760 1,000* * ** Guinea

grass, with

rate per month

CONCLUSION

The wastewater from pig farms contained a lot of NO3-N and NH4-N. About

60-80% of nitrogen in the wastewater was in both inorganic forms. The wastewater

could replace chemical fertilizers as much as 80-100% of the application rate

depending on type of growing crops. It could replace up to 100% of the chemical

fertilizers at the recommended rate of the chemical N for corn, sweet corn, sugar cane,

oil palm and cassava. The same results might be observed from the grass crops.

Better yield and nutrients of the crops were generally observed in the combination

treatment of the half dose of chemical N + the wastewater. In vegetable, such as

Chinese green mustard and/or Pak-choy, application of the wastewater could give the

yield 80-100% as much as those treated with chemical N.

The wastewater could replace some amount of water consumption of the

crops. For instance, the wastewater at the above recommended rate could replace the

irrigation water as much as 220,000 to 440,000, 187,500 to 375,000 and 380,000 to

760,000 L.ha-1

in one season of corn, Chinese green mustard and sugar cane

respectively. If the wastewater contained total N no higher than 100 mgN.L-1

, it could

replace irrigation water for the whole season in some crops. One appropriate method

for mitigation of water pollution from livestock effluents is the method of using it as

fertilizer and irrigation water. The wastewater should be collected in the lagoons and

it should be mixed with irrigation water before applying it to the crop fields at the

concentration about 100 mgN.L

-1

if the wastewater was supposed to use for the wholegrowing season.

ACKNOWLEDGEMENT

This project was financially supported by FAO. The author feels very much

appreciated with the kind assistance and support from FAO Regional Office for Asia


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and the Pacific, Thailand and Livestock, Environment and Development Initiative

(LEAD), Animal Production and Health Division, FAO, Rome. Strong support from

Department of Livestock Development, Ministry of Agriculture and Cooperatives is

gratefully acknowledged.

REFERENCES

Chunnasit, B., J. Pages and O. Duangngam. 2000. Incident of Bangkok city

development on peri-urban agricultural patterns and cropping systems evolution.

In Proc. on The Chao Phraya Delta: Historical Development, Dynamics and

Challenges of Thailands Rice Bowl. Kasetsart University, Bangkok.

Duangngam, O. and J. Pages. 2000. Nutrient recycling: an overview of Bangkok

peri-urban agricultural sector, an example of recycling technology: the Agrifiltre

process. In Mini-symposium on Nutrient Recycling for Peri-urban Agriculture.

Kasetsart University, Bangkok.

Harada, Y., K. Haga, T. Osada and M. Koshino. 1993. Quality of compost produced from

animal wastes. JARQ 26: 238-246.

Ministry of Agriculture and Cooperative. 1998. Data Statistic Ministry of Agriculture

and Cooperative.

Panichsakpatana, S. 1995a. Utilization of effluent from biogas production as nitrogen

source for Guinea grass (Panicum maximum Jacq.) grown on Kamphaeng Saen

soil. Kasetsart J. (Nat. Sci.) 29: 182-192.

Panichsakpatana, S. 1995b. Efficiency of some selected organic wastes as nitrogen

source for sweet corn grown on Kamphaen Saen soil. Kasetsart J. (Nat. Sci.)

29: 358-370.

Panichsakpatana, S. 1995c. Utilization of effluent from biogas production as nitrogensource for Pak-choy (Brassica campetris var chinensis) grown on Kamphaeng

Saen soil. Kasetsart J. (Nat. Sci.) 29: 445-453.

Panichsakpatana, S. 2003. Fertigation of some selected crops with wastewater from

pig farms: an appropriate method for mitigation of water pollution from

livestock effluents, pp 89-90. In the First Southeast Asia Water Forum.

SEAWF, IWMI, FAO, Chiang Mai.

Saridnirun, P and J. Pages. 1999. The Bangkok case: contribution of applied research

to peri-urban agriculture. In Proc. of Sub-regional workshop on the Constraints

and Opportunities for the Development of Urban and Peri-urban Horticulture in

South-east Asia. Min. Agriculture, Peoples Republic of China, FAO-UN.

thailand; recycling of wastewater from pig farms in urbanperi-urban agriculture

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