ENVIRONMENTAL

I M P A C T FROM A G R O C H E M I C A L S

IN B A L I

(INDONESIA) BADRUDDIN MACHBUB

Chief, Division of Environmental and Water Quality, Institute of Hydraulic Engineering, Bandung, Indonesia

H A R V E Y F. L U D W I G

Consulting Environmental Engineer, Seatec International, Bangkok and D. G U N A R A T N A M

Environmental Engineer, Worm Bank, Washington, D.C., U.S.A.

(Received April 1987) Abstract. Irrigation of paddy has been practised for centuries in Bali, based on the use of upland weirs for diverting river waters to irrigate downstreams lands ranging from upland terraces to flat coastal plains. While in earlier times, traditional irrigation practices have met the island's food needs, in recent decades an increasing population has increased food requirements to levels surpassing the productivity of traditional methods. Government assistance programs were initiated beginning in about 1960, and a major new program, called the Bali Irrigation Project, is now being implemented. These programs recognize that little additional farm lands will be available, hence their objective is to increase productivity through intensified agriculture, including the use of high-yield rice varieties and increasing amounts of agricultural chemicals, including both fertilizers and pesticides. The feasibility study for the Bali Irrigation Project included an evaluation of the pollutional effects of agricultural chemicals used in Bali. The study showed that past use of 'hard' organochlorides has pervasively polluted the island's soil and water resources and, while the Government's programs now use only relatively degradable chemicals, considerable environmental damage has already occurred and much care will be needed in avoiding the use of hard toxics in the future. The study also indicated no adverse effects from increased use of fertilizers.

I. Introduction Irrigation of paddy in the island of Bali, which has been practised for centuries, is characterized by a alrge number of independent irrigation schemes, stemming from the island's topography which divides the land into numerous small river valleys surrounding the volcanic mountains which make up a central core (Figure 1). Each valley's irrigable area is a communal entity which has been used for centuries, not only for irrigation purposes but also for managing cultural and religious activities. Generally, the irrigation systems in the valleys comprise an upland weir (small dam) which diverts the river into main irrigation canals which, in turn, furnish water to the farmlands stretching from the upland terraces to the flat coastal areas near the sea. While in earlier eras Bali was rice sufficient, in recent decades the population Environmental Monitoring and Assessment 11 (1988) 1-23. 9 1988 by Kluwer Academic Publishers.

9

Sabah Irrigation Mergaya Improvement Mertagaugga improvement Empas Improvement Kotapala Improvement Yeh Moran Improvement Tegak C,ede lmprt~vemcnt Tibubeleng improvement Benel Improvement $ilan~ana Improvemem Penarukan River Improvemem

Pulukan Irrigation

Bakung i~rigatlon

DJ~TA/LDF~IGN & C O N S T R U C T I O N Balian Irrigation Yeh leh Irrigation Sr Irrigation

a.

Reclamatio~

l~igation

Per~neak

Ababi

Palasari Irrigation Sangkan Gunung Irrigation Samplan Irrigation Angateh Irrigation

New Irrigation/Reclamation

II. STUDy'

L

9"

b,

Payangon Improvement Babah Hulu Improvement Aw,, Meliling lmpravemen~ Pencbel I m p ~ o ~ m c n t Ti~i~g Tali ~mprovemem Buruan Improvement Sungsang Improvement Gubug Improvement Bcngkel Improvement Nyitdah Improvement Bangyubiru Improvemem Yeh Satang Improvement Yeh Buah improvement Bading Kayu Improvement Babakan Mendoyo improvement Pengaringan Improvement Grokgak Improvement Mayong Improvement Joany~ Improvement Busungbia Improvemem Tegal/Bauyumala Improvement flajing [mprovement Tunggak Improvement Pan/Mallduang lmprovemem Balan Myah lmprovemenl Pansan Improvement Taro Improvement Klmug Improvement Auman Improvement Yeh Sayang Improvement Tebola Dauh De~ Improvement

Subak Improvement

~s

: SA'~t.IN'= f'OIm"

: c~s'rmc~- BOUNC)ARY

IOT~V

)

(~s/ T

,~C

Bali Environmental Analysis Base Map.

.

' ~w

INDONES/Xl - - OCE,4N

~v*=L=n ~ESmNse,cu= : s ~ sc.~a[ ~Ew =~basmoN/R[ct.,uA'no~ )upRov~u~wr

: VeLCA~O I~1 : L.AKE

~)

B : mv[R

b ,~ c : cou~oRu c A

&

....

LEGEND ;

Fig, 1.

&,~

L~c,

~wl& [ ] )* aATU

FIGURE I : BALI

/

[].

,Go,o

ENVIRONMENT~.L

6

";

ANALYSIS

BASE

MAP

N

ro

(15)

(14)

(11) (12) (13)

(10)

(9)

(8)

(1) (2) (3) (4) (5) (6) (7)

Unit

Population of Bali 1 000 Total forest area Total urban area Total length of roads Total farm land area Total paddy land area Total harvested paddy area (ha) Total dry gabah production (tons) Paddy (dry gabah), t o n s / h a irrigated area Dry gabah, kg/unit population Farm area per farm family Paddy area per farm family Percentage of paddy managed by: (a) Owners (b) Tenants Fertilizers (total): (a) Nitrogen (tons) (b) Phosphates (tons) Toxic agricultural chemicals (kg)

Indicative Parameters

ha ha

inh. ha ha km ha ha

E

. . --

.

.

.

-------

. .

.

.

.

--

. .

.

.

.

520 141 900 -----

. .

.

.

.

m

77 23

1 359 125000 -2 320 -90 352

1 677

680 10

74 26

2 320 280000 97 501

I 739 125 000

9 017

1 574 20

69 31

167

2.50

344 500

137 800

2 066 125000 9 578 2 322 280000 100535

1970

253 400

31 014 1 840

62 38

213 0.87 0.42

3.16

523 600

165 700

2 360 264 600 99 415

2 457 125000

1980

1960

1800

1900

P H A S E B (1960-(985) Government Assistance in Infrastructure and Farm Inputs

P H A S E A (to Circa 1960) Tradition Irrigation in Bali

1950

Evolution of irrigation practices in Bali and corresponding changes in environmental parameters

TABLE I

300 000

35 000 2 500

60 40

209

3.19

588 600

175000

85000

2 671 137 500

1985

50 50

189

3.29

3 400

183 400

110000

3 197 162 500

2000

PHASE C (1985 on) Implementation of BIP (projections)

4

BADRUDDIN MACHBUB ET AL.

growth has surpassed the rice-producing capacity of the traditional irrigation systems, which were operated by unique community agro/cultural/political organizations called 'subaks', which functioned in parallel with the usual town political entity. Government assistance has been necessary only since about 1960, in order to strengthen the irrigation facilities and to increase their productivity. This evolving change in the nature of Bali irrigation practices is illustrated in Table I. In historial perspective, irrigation practices in Bali may be categorized into three phases. Phase A represents the traditional practices, which lasted up to about 1960. Phase B represents the 1960-1980 period, featuring the beginning of government assistance programs. Phase C represents the projected situation for the future, including the effects of the Bali Irrigation Project, now being implemented by the government with the assistance of the Asian Development Bank. The Bali Irrigation Project (BIP) has the objective of strengthening and modernizing some 53 of the irrigation schemes in the island, as shown in Figure 1. The project area includes approximately 36 000 ha of paddy area out of a total island paddy area of about 100 000 ha. Generally, the improvements include rebuilding and/or strengthening components of the existing irrigation facilities, and new facilities as needed, plus improvement of the rural road network, together with proyision for use of modified paddy farming practices including use of agricultural chemicals, high yielding rice varieties, and crop rotation. To achieve further increases in yield will require a more intensified use of the available land. The feasibility studies for BIP were carried out in 1979-80 by an engineering consortium comprising Electroconsult (Elc) of Milan and the Agricultural Development Corporation (ADC) of South Korea, working under the Directorate General of Water Resources Development. The BIP feasibility studies included an environmental analysis of the entire project (including the 53 irrigation schemes and several other related water resource and land conservation projects), and the environmental analysis included an assessment of the effects on environment of agricultural chemicals used in Bali in the past and to be used in the future. The present paper presents a summary of that portion of the environmental analysis relating to pollution of the Bali surface waters resulting from use of agrochemicals.

2. Organization of Study The study of agricultural chemicals comprised (i) collection and evaluation of available data on the use of fertilizers and of toxic agrochemicals in Bali, obtained both from Government sources and from field surveys, (ii) a program of sampling/analysis of surface water and of soils/river bottom muds from selected points around the island, plus a sample for pesticide accumulation in prawns, to obtain information on existing types/amounts of pollution and their sources, and (iii) comparison of these data with similar information on experience elsewhere, including recent publications and releases of the U.S. Environmental Protection Agency (US/EPA). The detailed results of the study are included in the BIP feasibility study

E N V I R O N M E N T A L I M P A C T FROM AGRO CH E M I CA L S IN BALI

ACTUAL STUOY

5

USE 1969-1979

PROJECTION 1979- 1985 TONS /YEAR

40.000

/

30,000

J

20000

I0.000

/

j/

1.0oo

I I00

/ 1969

70

i 71

72

7'5

74

Fig. 2.

75

76

77

78

79

80

81

82

83

84

85

Agricultural Fertilizers Used in Bali.

report (in Volume 10 of the report, 'Environmental Analysis of Bali Irrigation Project' [1]). 3. Use of Agricultural Chemicals in Bali The findings of this evaluation are presented in Tables II, III, IV and V and in Figures 2 and 3. 3.1. USE OF FERTILIZERS IN BALI Fertilizers and other agricultural chemicals were used only marginally in Bali prior to 1970. With the introduction of farmer assistance (BIMAS/INMAS) programs of the Ministry of Agriculture in 1970, which were national programs including all provinces of Indonesia, use of agricultural chemicals started to pick up considerably.

BADRUDDIN MACHBUB ET AL.

6

KILOGRAMS

OR LITRES

500000 T )TA

;SE(

TIC

IDE

400.000

/~

300.000 200.000

/

I00.000

f

50.000 40.000 30.000 20.000 ~

/ ~/

--

,,,,,,

\

\ _/ IN

64 65

66

,/

k /

~'

,

67 6 8

/

io.ooo TOIAL ROI'NTICIs

5.000

/\

\/../

2000

,.ooo ~oo

/ \, X- -/,, 69 7 0

Fig. 3.

71

~oo 72

7 3 74

75 76

77

78 79

8 0 81

82 8 3

I00

84 85

Agricultural Pesticides Used in Bali.

In 1973 the government adopted a system of 'packages' of fertilizers including three categories as follows: Package

Where Used

A

High yield variety (HYV) areas

B

Traditional rice areas

C

Soils with high fertilizer requirement

Total kg yr-1 Urea

TSP

180-200

50

86-100

35

220-250

75

P a d d y yield (torts/ha)

Antrocol Dithane

Fungicides

Wafatex Wayfarin Tomorin D i p h a c i n 10 R a c u m i n (50 W P )

Zincphosphide

Rodenticide

T o t a l , K g per h a

T o t a l p a d d y area, h a

Total, Kg

Surecide (25 E C ) P h o s v e l (350 E C ) L e b a y c i d (55 E C ) F u r a d a n (3 G ) D u r s b a n (20 E C ) A g r o t h i o n (50 E C ) D i m e c r o n (50 E C ) F o l i t h i o n (50 E C ) B a s u d i n (10 G )

Endrin Dieldrin Aldrin DDT Malathion S u m i t h i o n (50 EC) D i a z i n o n (60 EC) T h i o d a n (35 E C ) Sevin (85 S P 50 W R )

Insecticides

Commercial Product

_ _

I 677

1 552 125

1963

E

1 533

1 520 13

1964

- -

--

1965

.

.

.

w

m

--

--

. . .

219

219

-

m

m

. . .

.

46 10

.

. . .

-

.

5 576 299

1970

.

. .

. .

.

. .

.

8 841

.

E

.

--

. . .

.

278

0.087

. . . .

.

. .

176

0.064

1 3 4 9 0 7 137 833

11 678

.

.

.

.

.

. .

.

.

. .

. .

1973

.

.

. .

14 751

.

.

.

- -

. .

. .

.

2 806

.

. .

--

. . . --2445 2 806 1 572 ------

.

10 700 34

1972

. . .

. .

. 23 024

.

. . 450 10656 50 2457 113 9 298 --

1974

in B a l i ( k g o r liter)

.

.

. .

. .

1978

5 349

11 231

10536 80 193 23 504 33 546 8663

. 523 22 575 42 455 105 700 2 722 2 840 14 896 4 4 2 9 0 336 333 6 969 46 200 8 659 672

1977

71 587 116 151 14 353 3 059 829 3642 2413 2 842 57 --

. 2 137 7 455 -25 680 3 588 5 135 8 618

. .

1976

93 385 141 852 207 844 3 9 0 2 8 3

8365

310 082 836 113 343 4 300 36

I 47 1 30

.

. .

1975

165 936

--

-17 894 456 50 474

453 95 330 -41 192 0.5 120 9 866

1979

. . .

.

219

0.079

. . .

m

. . . .

308

0.098

.

.

4

3.01

__

__

. .

46

0.020

. - -

.

--

--

. .

318

.

1003

0.149

.

3.12

--

--

- -

173

0,722

- -

3.05

45

267

1 230

1,012

175 15

3.13

--

2 356

- -

586

1.435

245

645

50

3.05

--

950

6 1 1

3 142

2.457

3.14

--

I 845

----

- -

2 162

1.002

50 842 149 964 142 737 154 560 129 414 1 4 0 1 8 9 1 4 4 8 7 8 158 830 165661

11 929

.

--

. 68 456 707

.

10 479 219

1971

production

. . . 2 810 . . 566 263 165 1 393 183 949 4

7 954 --

1969

. . .

231

.

440

.

--

-

9 704

.

. . .

3

. . .

.

---

287 325 104

8 983 5

1968

II

used for paddy

129

340

.

264 20

--

-

---

--

1967

. . .

-----.

--

1966

of toxic agrochemicals

171

171

Summary

TABLE

219

1966

46

1967

8 983

1968

59

7 954

7 958

1969

2 3 4 5 6 7 8 9

3.7

5 576

5 883

1970

21

10 479

10 480

1971

33

10 700

10 682

1972

43

Stop

22

Stop

1973

38

203

240 3

1974

44

68

1975

32

Stop

Stop

Stop

1976

(Tons)

Used for coconut plantations. Purchases from P.T. Pertani Denpasar. Stop means further sale forbidden by G o v e r n m e n t . For paddy pest control. Records not vailable for sales prior to 1696. Sales of aldrin said to be very small. No. records available except for 1969. Purchased from P . T . Pertani Denpasar. Except for B I M A S / I N M A S , na data were f o u n d on sales o f other organochlorides in Bali. No data available for year prior to 1962, nor for years after 1976 on sales/distribution o f organochlorides. A b o u t 400 tons yr-~ o f D D T used in each of years 1960, 1961, 1963 by Malaria Control Service, then use of D D T by Malaria Control Service discontinued until 1969 as shown. All used of D D T shown are by Malaria Control Service except for the 40 tons used in 1965 when P.T. Pertani sold 40 tons to farmers for insect pest control. D D T used by the Malaria Control Service in 1977, 1978, and 1979 was 51, 30, and 35 tons respectively.

(D) Other organochlorides 7

4.4

40

171

1965

(C) D D T 9

1 520

1964

287

Other Than B I M A S / I N M A S P.T. Pertani Denpasar5 Dewi Sri, Denpasar DPPB

1 552

1963

(2) B I M A S / I N M A S

(1) (a) (b) (c)

(B) Aldrin:

(2) B I M A S / I N M A S 6 (Table)

Totals

(1) Other Than B I M A S / I N M A S (a) P.T. Pertani Denpasar 4 (b) Dewi Sri, Denpasar (c) D P P B (Bali Agricultural ~ Estate Service)

(A) Endrin:

Pesticides Type and Source

Sale/distribution of organochloride pesticides in Bali (other than by B I M A S / I N M A S )

T A B L E IIl

total (tons yr -I) (kg h a - ~) (tons yr-1) (kg h a - 1)

350 800

2.60

134 900

--

681 185 8 0.06

1970

344 600

2.50

137 800

100 500

1 574 11 20 0.15

1971

4 t 0 300

2.72

150 800

.

4 155 28 66 0.44

1972

.

436 400

2.91

150 000

.

8 693 58 198 1.32

1973

429 600

3.01

142 700

.

23 172 162 223 1.56

1974

491 500

3.18

154 600

17 940 116 446 2.89

1975

Year

403 500

3.12

129 400

100 600

15 963 123 362 2.80

1976

427 600

3.05

140 200

98 900

19 031 123 416 2.97

1977

453 500

3.13

144 900

99 300

20 895 136 761 5.25

1978

484 400

3.05

158 800

99 500

24 209 144 893 5.62

1979

520 200

3.14

165 700

99 400

31 014" 152 1 840 11.11

Estimates shown above were developed by Project A g r o n o m i s t based on use of both G o v e r n m e n t statistics and Project field surveys. The field surveys i~dicated one unit of dry gabah produces approximately 0.658 units of finished rice (for Bali Irrigation Project conditions).

Total annual dry gabah production (tons)

Average dry gabah yield ( t o n s / h a / c r o p )

Total harvested paddy land area (ha)

Total paddy land area (ha)

Urea Urea TSP TSP

1969

Parameter

S u m m a r y of paddy production in Bali and fertilizers used

T A B L E IV

1965

1966

m

m

16 864 7 895 Rats Brown leaf hopper 3 023 2 915 White/yellow stemborer -223 Rice leaf folder 906 l 32l Rice bug Rice gall midge Rice thrips 113 854 Army w a r m / c a t e r p i l a r Soil bug Green leaf hopper 2 0 9 0 6 13208 Total 4042 5 313 Total for insects . . . Total paddy, 1 000 h a Percent of total paddy damaged by insects plus rates Percent damaged by insects alone Percent damaged by rats alone

Pest

Year

2595 2432

2006 1 866 .

i

m

180

--

--

m

637 112 1 408

1 816 170 437

912 -954

-

8309 7644 137.8

6,0 5.5 0.5

1.9 1.7 0.2

576

2 321 59 4 688

-

665

1970

2576 2337 134.9

-

239

172

140 -

1969

1968

1967

-

1.6

3.6

5,2

7851 5441 150.8

--

923 1 964 2 554

-

2 410

1971

1.4

1.7

3.1

4583 2597 150.0

429

1 986 110 727 515 818

1973

0.2

0.7

0.9

1351 1 030 142.7

.

-670 --

-

.

61.0 1.3

4.9

62.3

11.8 6.9

80577 78 986 129,4

.

591 912 978 814 547 54 --273

1 71 1 2 1

1976 1976

18267 10717 154.6

.

7 550 20 2 386 1 631 2 013 35 -1 829 15

321 -5 174 -88 -

1975 1975

1974

Pest d a m a g e in hectare

P a d d y pest d a m a g e in Bali

TABLE V

2.4

13.6

16.0

22378 19 061 140.2

.

3 317 10815 2 997 4 005 1 166 538 265 279 15

1977 1977

5.0

11.6

16.6

24011 16 775 144.9

7236 9479 2 472 2 413 1 404 79 272 84 47

1978 1978

4.3

14.5

18.8

29912 23 072 158.8

3

6840 13 461 7 320 3 749 892 87 141 2 158 109

1979 1979

-

3.2

14.6

17.8

29547 24 170 165.7

-

4 287 2 443 80 232 1 780 8

5 377 8020

1980

ENVIRONMENTAL IMPACT FROM AGROCHEMICALS IN BALI

ll

The actual usages in Bali have been considerably less than the recommended levels. Actual usages in 1967/77 were approximately 23, 120, and 75 kg urea respectively and about 5 kg h a - 1 of TSP [2]. Inspection of Table IV indicates actual use of urea has recently been in the range of 150 kg y r - 1 and of TSP about 5 kg y r - 1. Use of these amounts of fertilizers, plus the toxic agrochemicals for pest control, has resulted in a gradual ihcrease in paddy production from about 2.5 tons h a - ~ in 1969 to more than 3.0 tons h a - 1 by 1980. With respect to farmer acceptance of Government recommendations, the data on crop production show that Jn the 1973 and 1976 crop years there were marked reductions in the usage rates as a result of a severe drought in 1972 and a major infestation of Wereng (brown leaf hopper) in 1973. Even when they have ready access to farm credits (as provided by BIMAS) the farmers have sometimes been reluctant to adopt the BIMAS packages for fertilizers/toxic agrochemicals, especially where failures are still fresh in the farmer's memory. 3.2.

ENVIRONMENTAL

EFFECTS

OF FERTILIZERS

Use of fertilizers in Bali has not so far caused any known significant adverse environmental effects. The fact that paddy irrigation in Bali involves continuing water reuse, in flowing by gravity from paddy to paddy from the hills to the sea, serves to minimize loss of fertilizer. Also, the farmers themselves are sensitive to fertilizer cost, hence they tend to regulate paddy flow releases to minimize the loss. For purposes of environmental analysis it is concluded that (i) the presently established levels of recommended fertilizer use as indicated above are likely to continue to represent government ceiling recommendations for the foreseeable future, and (it) the actual usages will continue to be less or not much more than the recommended levels. While the average applications of urea may reach the 2000 kg y r - 1 goal, the applications of TSP will likely remain in the range of less than l0 kg h a - I per year. However, because the actual dosages of TSP are far below the recommended levels, if would seem that this subject needs to be re-examined by BIMAS. Either the standard is too high or the application practice is too low. Bases on experience elsewhere in both industrialized and developing countries, and in recognition of ever-increasing food demand because o f population pressures, it appears certain that Bali agriculture will continue to use fertilizers, probably in increasing amounts, as better knowledge is developed on how to select and use the fertilizers for optimum results. Properly utilized, fertilizers can markedly increase production from a given area of land [3], and given the limited land area in Bali, it will probably be necessary to maximize its unit agricultural productivity. From the point of view of impact on natural environmental resources, such as eutrophication o f natural water bodies, the nutrients lost to environment from irrigated paddy represent only a very small part of the total nutrient input. The major resources will continue to be from natural erosion as well as other human activities and operations. It is not indicated that the increased nutrient inputs to environment from irrigated agricultural will have any significant effects. There may be some local

12

BADRUDDIN MACHBUB ET AL.

eutrophication (as well as sanitary) problems associated with increasing urban growth in the urbanized zones of the island. 3.3.

U S E OF TOXIC A G R O C H E M I C A L S IN BALI

The history of experience with toxic agricultural chemicals in Bali is shown in Table II (on kinds and amounts used), and in Table V (on kinds and amounts of pest damage). Most of the toxic agrochemicals used to date have been insecticides, with relatively small amounts for rodenticides and fungicides. Table II also shows that the prior to 1968 there was negligible use of toxic agrochemicals in Bali, but since 1968 the usage has steadily increased both in total amounts and in amount per hectare. Examination of Tables II and V indicates the following: (i) Although usage of pesticides was very low prior to 1973, less than 0.1 kg h a - l,the toxic materials utilized in these earlier years were mostly 'hard' organochlorides which tend to persist in the environment and to result in severe environmental damage even though used in small amounts. In fact, the environmental effects elsewhere in Indonesia were so severe that, beginning in 1973, the government discontinued use of all long-persisting pesticides and since has utilized relatively degradable pesticides (such as Diazinon and Sevin) believed to be relatively safe. This shift in policy was most timely in that the quantities of pesticides used in Bali since 1973 have steadily increased reaching 2.5 kg h a - 1 in 1978-79 (and a total of more than 390000 kg). (ii) Despite the increasing use of insecticides since 1973, this does not seem to be reflected in insect damage to paddy as shown in Table III. Whereas prior to 1973 the percentage of total paddy area damaged by insects was fairly low (of the order of 5070), since the Wereng outbreak in 1975-76 the damaged area has held at about 14~ Also, yields have not markedly increased despite the increased use of insecticides. (iii) It would seem that entire subject of insecticides uses in Bali needs careful reexamination, specific for Bali conditions, both to be sure the methods of application and use are appropriate and efficient, and that the extra yields justify the extra input costs (including hazards to environment). With respect to methods of using the insecticides, the BIP agronomy studies have indicated the need for better timing in use of the pesticides for control of Wereng, and also for some crop rotation. 3.4.

E N V I R O N M E N T A L EFFECTS OF PESTICIDES

A primary consideration affecting environmental hazards is persistance of the active ingredient in the soil (and sediments of rivers). Because of the importance of this subject the U.S. Environmental Protection Agency (US/EPA) has reviewed all available information on susceptibility to biodegradation in the soil environment [4]. The available data on persistence for the toxic chemicals now and previously used in Bali, together with information on safe allowable limits of these materials in natural waters, are shown in Table VII. Also shown are the amounts of these pesticides found in the soils and natural waters of Bali by the BIP water/soil quality surveys.

0.009

(B) Organophosphates: Diazinon

16 16 16 16 16 16 16 16 16

Total No. Sampling

U S / E P A standards for aquatic ecology (Ref. 8). 2 Number of samples showing presence of pesticide.

(C) Carbonates: Sevin (Carbaryl)

0.002

0.003 0.001 0.003 0.004 0.01 0.002 0.002

Safe t Limit (mg l-l)

(A) Organochlorides: Aldrine DDT Dieldrin Endrin Lindane BHC DDE Fenitrothien DOD DDD

Pesticide

6 0 12 0 13 3 0 0 0

Positive2 Samples

0.1-0.6 -0.03-1.3 -0.01-0.05 0.1-0.5 ---

Range (mg 1 ~)

Dry Season

6 12 12 0 13 3 0 0

No. Over Limit

Pesticide residuals found in Bali rivers

TABLE VI

15 15 15 15 15 15 15 15 15

Total No. Sampling

12 0 0 1 12 10 9 9 1

Positive2 Samples

0.001-0.08 --0.04 0.03-1.0 0.2-0.3 0.1-0.3 0.1-0.3 0.05

Range (mg 1 t)

Rainy Season

12 0 0 1 12 10

No. Over Limit

14

B A D R U D D I N M A C H B U B ET A L .

Because of the adverse effects of the hard pesticides used in Indonesia prior to 1973, including a massive fish kill episode in East Java, the Government in 1973 established a new poliby by which all toxic agricultural chemicals distributed by BIMAS/IMMAS are subjected to testing by the Inland Fisheries Research Institute at Bogor. As a result use of organochlorides and other hard pesticides have been banned since 1973 and approval given only to degradable pesticides such as organophosphates and carbamates. The conclusions that may be made on the environmental aspects of pesticides use at Bali, based on the information available at this time, are summarized as follows: (i) The use of pesticides with active ingredients which persist for prolonged periods in the soil (and throughout the environment), which was discontinued in Bali after 1973, should continue to be prohibited. These include DDT and other organochlorides substances, including endrin, dieldrin, aldrin, and malathion, which were used prior to 1973, and should also include heptachlor, parathion, methylparathion, and chlordane. All of these have been either banned or restricted in Western Europe and/or the U.S.A. [5]. Instead of non-biodegradable toxicants, emphasis should continue to be placed on use of pesticides which, while more expensive, are known to be degradable. DDT and other organochlorides can be replaced with persistent yet bio-degradable analogues such as methyoxychlor, ethoxychlor, and methylchor, and aldrin may be replaced with ditrydroheptachlor. Parathion and methylparathion may be replaced with ferthion, fenitrothion, dicapthon, ronnel, bromoplus, and idophephos. Generally the organophosphorus and carbamate classes of insecticides have excellent degradabilities. Insecticides containing toxic metals such as mercury, arsenic, copper, and lead (which are totally non-degradable) should also continue to be banned. (ii) As noted in [3], contrary to the thinking of some people, the use of pesticides for pest control is not per se an ecological sin. Where the use is approached on the basis of ecological principles, they contribute heavily to irrigated agriculture and in many situations appear to be indispensible in the developing countries and elsewhere because of demands for increased food production. Successful pest management requires (a) direction of programs by trained specialists, (b) replacement of regular routine/package type pesticide applications by tailored applications, (c) recognition that many crops can tolerate substantial levels of pest infestation without economic loss, and (d) changes in agronomic practices to make control an integral part of overall crop production so that proper pesticides are chosen and used in the right amounts at meaningful times (when they are needed to do their ecological job). Some suggestions on such agronomic improvements have been prepared by the BIP Project Agronomist [2]. (iii) Because of the special characteristics of Bali agriculture (as compared to Indonesia in general) it is recommended that the Provincial Agricultural Service undertake a much more intensified program of continuing study for determining the most appropriate pesticide practices for Bali, for supplementing the guidance given

E N V I R O N M E N T A L I M P A C T FROM A G R O C H E M I C A L S IN BALI

15

by the Central Government. This would include use of the Environmental Center of the Bali's Udayana University for continuing monitoring of toxic accumulations in the Bali environment. It is believed, if such a program is appropriately organized, significant funding assistance could be obtained from the International Assistance Agencies. (iv) In the long term, assuming the above recommendations are followed, it is believed there will be no serious long-term degradation of Bali environmental resources. Continuing internationally-sponsored research will likely result in production of much more degradable (yet effective) toxic agrochemicals over the next several decades, and in better procedures and techniques in using them to minimize losses to the environment. With careful controls a favorable ecobalance seems feasible despite the ever-increasing use of these substances. 3.5. SELECTIONOF TOXIC AGROCHEMICALS At present the main pesticides utilized in Bali by BIMAS/IMMAS are reported to be Diazinon, an organophosphate, and Sevin, a carbamate. Both are relatively degradable and, judging by the latest information from the US/EPA, are considered to be reasonably safe for use under Bali conditions. Because of the residuals in the Bali soils of the organochlorides previously used, their effects on aquatic ecology can be expected to mask the far lesser effects of soft pesticides such as Diazinon and Sevin. However, the effects of the soft pesticides will become progressively more important, and only a continuing monitoring program will furnish the basic data needed for guiding the Government's policies on future selection of pesticides. While other toxic agricultural chemicals are used in Bali, such as rodenticides and fungicides, the amounts of those are relatively very small, and these too are becoming subject to tests and controls so that only degradable compounds are approved for official distribution. Hence these other toxicants are believed to exercise relatively negligible effects on environment. 3.6. NON-AGRICULTURALTOXIC CHEMICALS Information on non-agricultural uses of toxic chemicals in Bali (including illegal uses) was obtained by visits to both government agencies and the private sector. The information indicates that, since the mid-1970's there have been practically no officially recorded sales of organochlorides in Bali except for continuing sale of DDT for use by the Provincial Malaria Control Service. However, in the field visits, statements were heard from time to time that Endrin was being continually used for illegal fish killing. It is believed that considerable sale/use of particular organochlorides may be continuing at levels possibly inimical to natural ecological resources as well as to human health. It is therefore recommended that the proposed environmental monitoring program include collection of meaningful data on continuing use of organochlorides, especially DDT and Endrin.

16

BADRUDDIN MACHBUB ET AL.

4. Water and Soil Quality Surveys 4.1. SAMPLINGSTATIONS To gain more basic information on the present extent of environmental pollution in the project area, and on the role of agricultural chemical residuals in the overall pollution complex, the environmental study included a modest program for sampling and analysis of river/paddy water samples, plus a few soil samples from four selected irrigation schemes, namely from Sabah, Mertagangga, Yeh Leh, and Palasari. The analyses included both field and laboratory determinations. A total of 18 surface water sampling points were used (river or paddy water), selected to represent conditions above, in, and below the irrigated areas, plus seven sampling points for paddy waters, four sampling points of river bottom muds, and one composited prawn sample from the Perancak fish ponds. The sampling were made for two seasons of the year, for the rainy season in February 1980 and for the dry season in July 1980. Additional samples were taken for bacteriological/coliform analysis of the canal waters at one or two places in each of the four areas, where the canal waters are commonly used for bathing. While the program was limited, nevertheless the data obtained are believed sufficient to be meaningful and representative of conditions in the project area and in Bali province. Also it is believed this survey may be the first such effort in Indonesia to obtain systematic information on the effects of agrochemicals in an irrigated cropping zone.

4.2.

SELECTION

OF PARAMETERS

4.2.1. Surface Waters Because the pollution in the surface waters comes from many sources, in an effort to obtain some information on relating pollution to sources, the parameters chosen for analysis of the surface water samples included (i)all pertinent physical and chamical parameters on water quality including those relating to natural mineral water quality and indices of pollution from sanitary and industrial wastes, and those relating to the suitability of the river waters for irrigation of paddy and other crops, and (ii) special analyses for pesticides residuals. 4.2.2. Soils/River Bottom Muds~Prawns The pesticides residual analyses were made not only for the surface water samples, but also for the soils, river bottom muds, and one composited prawn sample. 4.2.3. Canal Water/Coliforms For these samples the determinations included both total coliforms and E. Coli, as indicators of human excreta contamination.

17

E N V I R O N M E N T A L I M P A C T FROM AG RO CH E M I CA L S IN BALI

4.3. INTERPRETATION OF RESULTS 4.3.1. Suitability of River Water for Irrigation and Other Uses The data on stream water quality in Bali show all of the stream waters (Table 7) to be of excellent quality for paddy and for virtually all crops except possibly those very sensitive to boron. The waters are low in total dissolved solids and in chlorides, and have very favorable cation/anion balances resulting in very low SAR (sodium absorption ratio) levels. The waters may be classified as preponderantly bicarbonate/divalent cation waters, as is characteristic of most river waters in Indonesia [5]. The low total dissolved solids are no doubt due to the relatively short length of the Bali streams and to the fact they traverse mostly mountainous terrain before reaching the irrigation diversion weirs. Table VII also shows that the natural mineral quality of the surface waters is excellent for virtually all human activities (as well as for aquatic ecology), including domestic and industrial purposes. In addition to low total dissolved solids, the total hardness is not high (in the range of 100 mg 1-1 as equivalent calcium carbonate), the iron and manganese contents are not high (and do not appear to cause problems of water discoloration), no significant toxic heavy metals were found, and (before

TABLE VII Typical water quality characteristics for Bali rivers Characteristics

Dry Season

Rainy Season

Average

Total Dissolved Solids (mg 1-~) Suspended Solids (mg 1-i) Temperature (C) Color (PtCO) pH Alkalinity (mg 1 as CaCO3) Sodium (Na) (mg 1-i) Potassium (K) (mg 1-1) Calsium (Ca) (mg l i) Magnesium (Mg) (mg 1-l) Hardness (Ca+Mg) (mg 1 as CaCO3) Bicarbonate (HCO3) (mg 1-~) Chloride (C1-i) (mg 1-~) Sulfate (SO4) (mg 1 J) Nitrate (NO3) (mg 1-1) Nitrite (NO2) (mg 1-~) Iron (mg 1-~) Manganese (mg 1-~) Boron (mg 1-~) Zinc (Zn) (mg 1-~) Phosphate (PO4) (mg 1-~) BOD (mg 1-~) COD (mg 1- t)

240 90 29 20 7.35 123 14 6 27 12 118 150 14 6 1.0 0.002 0,2 0.05 0.5 0.05 1.0 2.4 15

170 140 29

205 115 29 12 7.35 118 12 5.5 24 11.5 109 144 14 4 1.0 0.5 0.15 0.2 0.3 0.45 0.7 2.1 15

7.35 112 10 5 21 11 100 137 14 2 1.0 0.1 0.11 0.4 0.03 0.04 0.3 1,8 15

18

BADRUDDIN MACHBUB ET AL.

reaching hte farm areas) the river waters are relatively unpolluted. They do contain significant suspended solids (turbidity), expecially in the rainy season, and significant amounts of colloidal color in the dry season. Both o f these would need to be removed by rapid sand filtration to obtain a first-class water for domestic/industrial USES.

4.3.2. Sanitary o f River and Canal Waters The data on organic pollution (Table VII), namely BOD, COD, and nitrates/nitrites, indicate significant pollution from excreta in the stream waters, but not at high levels, not even in the dry season. For example BOD levels are all in the 1 to 4 mg 1- 1 range. However, this pollution represents sufficient contamination so that the water cannot be safely used for domestic purposes except after treatment (disinfection a n d / o r filtration). Even so, the canal waters are probably much less contaminated that the shallow well waters commonly used for domestic supply. The total coliforms in the canal waters are usually somewhat above about 20 MPN (number per 100 ml), compared to the level of 1 MPN which is utilized internationally to represent a safe drinking water supply. However, there was relatively little evidence of E. Coli, which is specific for coliforms in the excreta of mammals. The conventional U S / E P A standards for fecal coliforms for stream waters to be used for fresh water bathing correspond to an average E. Coli density of 200/100 ml [61, which is much higher than the values found in the BIP study (usually under 10). While the data on E. Coli are of course limited, they do not indicate the canal waters are unsuitable for bathing. The coliform levels in the canal waters are relatively very low compared to shallow ground waters commonly used in urbanized areas of Indonesia, where the total coliform MPN levels are often in the thousands or higher. This is the case at Jakarta, for example, where the heavily contaminated shallow ground waters are the major source of domestic supply for probably a million or more residents of the kampungs [8].

4.3.3. Pesticides in Surface Waters The surveys showed that the hard organochloride pesticides used prior to 1973 still persists in the surface water in the farm areas, in amounts sufficient to exercise serious adverse effects on stream fisheries and aquatic ecology (Table VI). While limited, the data show that the residual concentrations of the organochlorides measured, for which safe concentrations are known, namely Aldrin, DDT, Dieldrin, Lindane, BHC (benzin haxachloride), and DDE, are considerably in excess of the U S / E P A recommended limits. The data indicate that the aquatic ecology of the Bali streams has been seriously impaired by the use of organochloride pesticides, particularly when it is considered that their effects are often accumulative, i.e., the impact may be considered as the sum of all the organochlorides acting together. The data on Table VI on surface water residuals are not sufficient to indicate differences in levels of the organopesticides in the upstream farming areas compared

490 460 46 53 326 254 620 321 18 20-790

45 60 76 70 77 60 70 65 11 2-490

Aldrin (HL = 0.3) 2, 3

ND 13 13 13 22 ND ND 9 12 --

Lindane (HL = 1.2) 2, 3

ND 6.6 6.6 6.6 21 ND 25 9 -2-269

BHC

O

,-.q

>

K z -I > [-,

7


~., ~ m K

July July July July July July July

Dieldrin (HL = 2.5) 2, 3

>

15 15 17 17 16 16 24

Sampling Date (1980) J

Sabah Palasari Mertagangga Yeh Leh Taiwan river muds (1972) (Ref. 213) USA bottom sediments (Ref. 216)

S/1 S/2 S/6 S/7 S/3 S/4 S/5

Sampling point

Measured Concentration, ( H g / k g ) (Parts Per Billion) 4

River bottom muds:

S a b a h / U p p e r Area S a b a h / L o w e r Area Palasari/Upper Area Palasari/Lower Area M e r t a g a n g g a / U p p e r Area M e r t a g a n g g a / L o w e r Area Yeh Leh Average Taiwan paddy soils (1972) U S A cropping soils

Paddy soils:

Sampling Place/Item

T A B L E VIII Pesticide residuals found in Bali soils and prawns

20

BADRUDDIN MACHBUB ET AL.

with the lower reaches. Nor are they sufficient to differentiate between rainy and dry season levels. The residuals in the soil seem to gain access to the stream waters throughout the year. Information on the persistence of organochloride pesticide residuals in soils is given in several references [8, 9, 10]. In general the data indicate (i) half-life levels are from about 2.8 yr for DDT to 0.3 yr for Aldrin, (ii) the time required for degradation of 95~ of the pesticide ranges from about 3 to 11 yr, and (iii) after 6 yr (considering that distribution of hard pesticides by BIMAS/INMAS was discontinued after 1973), while most of the Aldrin should be gone, about 20% of the DDT, about 15~ of the Dieldrin and Eldrin, and about 8O/oof the Lindane should remain. This information indicates that the remaining residuals of organochlorides pesticides will continue to persist in the Bali environment at low inimical levels for one or more decades. 4.3.4. Pesticides in Paddy Soils Data on accumulation of selected organochloride pesticides in project area paddy soils are given in Table VIII. While the data are too limited to show differences in accumulation between upper and lower paddy areas, they do show serious levels of accumulation. The accumulation is highest for Dieldrin (average 321 #g kg- 1) and lowest for Lindane and BHC (average 9/tg kg- 1). For all 28 soil samples the average total accumulation of all pesticides is about 100 #g kg- 1. Table VIII also shows levels of accumulation of organochlorides in paddy soils in Taiwan reported in 1972 [9] and also as reported for hte U.S.A. [6]. The accumulations in Bali soils are noted to be generally higher than for Taiwan (as of 1972-73), especially for Dieldrin and Aldrin. The Bali levels are comparable to the accumulations which occurred up to about 1972-73 in the U.S.A. 4.3.5. Pesticides in Prawns The data of Table VIII relating to pesticides in prawns represent a composited sample of prawns taken from a group of aquaculture ponds at Perancak. The levels of pesticide accumulation in the Perancak prawns correspond to similar accumulations elsewhere in earlier years when organo-chlorides pesticides were commonly used. 4.3.6. River Bottom Muds Table VIII shows that accumulations of pesticides in some of the river bottom muds at Bali are much higher than accumulations in Bali soils, and much higher than similar accumulations in river bottom sediments elsewhere. 5. Summary and Conclusions 5.1. POLLUTION DISCHARGESTO BALI RIVERS Based on the surveys noted above and on other data collected by the study, an

ENVI RONMENTAL I M P A C T FROM AGRO CH E M I CA L S IN BALI

21

estimate was made of the amounts of pollution reaching the sea from all the rivers o f Bali island, using nitrogen and phosphorus as the parameters. The results of the study are summarized as follows: Sources of pollution

Wet season Nitrogen as NO3 (rag 1- l)

Dry season P h o s p h o r u s as PO4 (rag 1- i)

0.12 0.70 2.30 0.014

0.17 0.14 4.70 0.03

3.13

6.10

0.007 0.006 0.06 0.00002

0.01 0.01 0.12 0.00003

Total

0.07

0.14

Actual (measured) river concentrations: Nitrite Phosphate

1.0 0.3

1.0 1.0

Nitrogen Soil r u n o f f H u m a n excreta Animal excreta Fertilizers Total

Phosphorus Soil r u n o f f H u m a n excreta Animal excreta Fertilizers

As indicated by the data, the contribution of agrochemicals in the total pollution loadings discharged to Bali rivers is negligible (less than one percent). Also, the data indicate that much of the nitrogen reaching the rivers is removed from solution by being taken up in biomass or bottom muds or otherwise. 5.2. ENVIRONMENTAL IMPACTS OF AGRO-PESTICIDES IN BALI (a) The BIMAS/INMAS program for distribution in Bali of pesticides and other toxic agricultural chemicals began in the 1960s with the use of mostly hard or persistent organochlorides, which were increasingly used up to 1973 when the program was modified to discontinue use of hard pesticides and instead to use soft or relatively degradable pesticides. This change in use of pesticides in Indonesia was similar to practices elsewhere in most countries, virtually all of which implemented bans against use of hard pesticides in the early 1970s. (b) The organochloride pesticide residuals which have accumulated in Bali soils from agricultural and other practices are quite high, but are comparable to similar accumulations which occurred elsewhere over the same period when organochlorides were commonly used. The levels of accumulation at Bali are however, much higher than for Taiwan. (c) The organochloride residuals in the Bali soils impart contamination to the Bali environment on a continuing basis, including contamination of surface water and

22

BADRUDDIN MACHBUB ET AL.

of aquatic animals including prawns. The levels of contamination much exceed recommended sage levels for aquatic ecology, especially considering that the effects of the different types of organochlorides are cumulative. Hence the Bali rivers have been seriously contaminated from the point of view of fishery reproduction, and serious levels of contamination will probably persist for at least another decade. (d) The accumulations of organochlorides in Bali river bottom muds seem to be much higher than in the soils, and much higher than reported elsewhere. These data do not seem to be consistent with the soils data, but if true they indicate serious levels of contamination. (e) The pesticide concentrations now found in the Perancak prawns correspond to concentrations found in shellfish elsewhere when hard pesticides were commonly used. (f) The environmental effects of soft pesticides now used in Bali are believed to be far less than the ongoing effects of the organochlorides, hence at this time the effects of the soft pesticides are probably masked by the residual organochlorides. (g) It is important that a competent program for continuing monitoring of pesticide residuals in the Bali environment be established, to furnish the basic data for guiding future Government policy on toxic chemicals to be distributed in Bali, both in the public and private sectors, for agricultural and all other purposes. This is a function which could readily be carried out by the Bali Environmental Center of Bali's Udayana University. The BIP environmental report includes a recommended comprehensive minimum meaningful periodic environmental monitoring program to be conducted by the Environmental Center, covering all significant environmental parameters including impacts of agricultural chemicals. 5.3. APPLICATION OF CONCLUSIONS TO OTHER DEVELOPING COUNTRIES

The change in use of agro-pesticides in Indonesia, from hard pesticides prior to the early 1970s to soft pesticides thereafter, resulted in a marked change in response in effects on aquatic ecology, from a situation featuring numerous fish kills and complaints to a situation with virtually no complaints reported since the changeover. It appears that use of soft pesticides for agriculture in regions similar to Indonesia (tropical monsoon climate regions) should not pose significant environmental hazards. The increased use of fertilizers in Indonesia, to support use of high yielding varieties and higher yields, has not resulted in any significant runoff/eutrophication problems, and similar expectations would seem to apply to other similar climatic regions. References [1] 'Environmental Impact Assessment, Bali Irrigation Project', by Institute of Hydraulic Engineering/H. Ludwig for DGWRD, Bandung, Indonesia, January 1981. [2] 'Bali Irrigation Study, Final Report, Annex A, Agronomy', by Bali Irrigation Study Team for DGWRD, Denpasar, Indonesia, December 1977.

E N V I R O N M E N T A L I M P A C T F R O M A G R O C H E M I C A L S IN BALI

23

[3] 'A Primer on Agricultural Pollution', Soil Conservation Society of America, Ankeny, Iowa, 1971, 22 pp. [4] 'The Degradation of Selected Pesticides in Soil: A Review of the Published Literature', J. R. Sanborn et al., US/EPA Cincinnati (Ohio), August 1977. [5] 'Persistent Pesticides in the Environment, 2nd Edition', C. A. Edwards, CRC Press, Cleveland, Ohio, 1976. [6] 'National Water Quality Monitoring Program of Institute of Hydraulic Engineering', H. F. Ludwig and Badruddin Machbub. Institute of Hydraulic Engineering, Bandung, 1978. [7] 'Water Quality Criteria, 1972', US/EPA Publication EPA/R3/73/033/March 1973. U.S. Environmental Protection Agency, Washington, D.C. [8] 'Quality Criteria for Water', U.S. Environmental Protection Agency, July 1976. [9] 'Report on Raw Water Quality, Jakarta Water Supply', by H. Ludwig for World Bank, July 1982. [10] 'Monitoring of Pesticide Residues in Taiwan', Gwo-Chen Li, Taiwan (1978).

Environmental impact from agrochemicals in Bali (Indonesia).

Irrigation of paddy has been practised for centuries in Bali, based on the use of upland weirs for diverting river waters to irrigate downstreams land...
1MB Sizes 0 Downloads 0 Views