The Effects of Paddlewheel Aeration on the Pond Production of Associated Natural Food Organisms under the Monoculture System of Macrobrachium rosenbergii (de Man)

Table 1. Average of phytoplankton abundance (1,000 plankter/litre) in the ponds during experiment period.

Organism group	With paddle wheel aeration
Organism group	9 Dec.	24 Dec.	7 Jan.	21 Jan.	4 Feb.	18 Feb.	4 Mar.	18 Mar.	2 Apr.	15 Apr.	29 Apr.	13 May	27 May	10 Jun.
Chlorophyta	23	161	31	472	33	62	82	167	870	221	5352	700	922	132
Chrysophyta	52	52	180	73	138	54	196	617	441	472	2413	1106	479	261
Cyanophyta	21	17	83	28	693	348	1868	15776	3513	10782	18718	15299	11096	7320
Euglenophyta	5	0	1	4	2	35	18	119	40	130	1117	590	700	98
Phyrophyta	0	0	1	12	11	16	1	0	28	0	0	0	0	1
Total	100	230	295	589	876	514	2165	16680	4892	11604	27600	17695	13197	7811

Without paddle wheel aeration
Chlorophyta	164	35	116	93	165	252	71	33	992	299	175	406	406	216
Chrysophyta	134	47	88	122	125	209	213	79	629	255	1867	590	406	420
Cyanophyta	15	38	64	20	315	984	3187	1438	9251	9501	14319	13787	14685	17626
Euglenophyta	7	2	1	3	13	39	24	5	33	77	828	184	516	168
Phyrophyta	0	0	1	3	27	34	3	1	2	0	0	0	0	0
Total	318	121	269	240	645	1518	3496	1556	10907	10131	17189	14966	16012	18429

Table 2. Maximum (N), Time (t) to reach maximum population and exponential growth rate (r) of phytoplankton during experimental period

		With paddle wheel			Without paddle wheel
Organisms group		N (1,000 p1/1)	t (weeks)	r	N (1,000 p1/1)	t (weeks)	r
Chlorophyta	Pond 1	1,421	16	0.4	1,797	16	2.1
	Pond 2	10,617	20	2.0	442	22	0.2
	Average	6,019	18	1.2	1,120	19	1.2

Chrysophyta	Pond 1	885	22	0.2	3,439	20	1.8
	Pond 2	4,424	20	0.6	885	22	0.5
	Average	2,65	21	0.4	2,162	21	1.2

Cyanophyta	Pond 1	12,829	22	0.4	23,551	20	0.9
	Pond 2	28,102	14	1.0	20,449	24	0.3
	Average	20,466	18	0.7	22,000	22	0.6

Euglenophyta	Pond 1	465	20	0.7	811	24	0.5
	Pond 2	1,770	20	0.9	1,475	20	0.7
	Average	1,118	20	0.8	1,143	22	0.6

Phyrophyta	Pond 1	28	16	0.6	19	10	0.3
	Pond 2	31	10	0.3	49	10	0.4
	Average	30	13	0.5	34	10	0.3

T o t a l	Pond 1	14,893	22	0.3	27,227	20	0.9
	Pond 2	44,384	20	0.7	21,408	24	0.3
	Average	29,639	21	0.5	24,318	22	0.6

Table 3. Average zooplankton abundance (plankter/litre) in ponds during experiment period.

Organism group	with paddle wheel aeration
Organism group	9 Dec.	24 Dec.	7 Jan.	21 Jan.	4 Feb.	18 Feb.	4 Mar.	18 Mar.	2 Apr.	15 Apr.	29 Apr.	13 May	27 May	10 Jun.
Rotifer	10	402	1125	790	216	322	367	223	1270	2425	565	1188	1267	247
Cladocera		83	15	6	3	8	4	2	1	3	1		1	6
Copepoda
Nauplius	25	222	39	167	98	95	282	155	353	155	140	188	253	419
Adult	6	178	77	77	80	33	180	79	236	197	278	213	114	109
Total	18	885	1255	1040	396	457	832	463	1860	2778	983	1588	1634	780

	Without paddle wheel aeration
Rotifer	6	243	864	325	603	370	293	195	884	2045	625	947	501	167
Cladocera		25	11	27	13	22	6	2	1		1		1	4
Copepoda
Nauplius	3	137	73	60	87	127	212	132	202	54	111	168	220	227
Adult	10	145	56	89	130	67	165	59	169	242	257	89	134	143
Total	18	549	1003	500	832	585	675	389	1255	2340	993	1203	855	540

Table 4. Maximum (N), Time (t) to reach maximum population and exponential growth rate (r) of zooplankton during experimental period

		With paddle wheel			Without paddle wheel
Organisms group		N(plankter/1)	t (weeks)	r	N (plankter/1)	t (weeks)	r
Rotifer	Pond 1	3,505	18	0.6	3,366	18	0.6
	Pond 2	1,344	18	0.7	1,042	22	0.4
	Average	2,425	18	0.7	2,204	20	0.5
Cladocera	Pond 1	38	2	1.8	23	2	1.1
	Pond 2	127	2	2.4	43	10	0.4
	Average	83	2	2.1	33	6	0.8
Copepoda	Pond 1	476	16	0.8	270	24	0.2
Nauplius	Pond 2	338	12	0.3	169	24	0.3
	Average	407	14	0.6	220	24	0.3
Copepoda	Pond 1	261	18	0.2	426	18	0.4
Adult	Pond 2	393	20	0.2	299	20	0.4
	Average	327	19	0.2	363	19	0.4
T o t a l	Pond 1	3,994	18	0.5	3,863	18	0.5
	Pond 2	1,562	18	0.4	1,319	20	0.2
	Average	2,778	18	0.5	2,591	19	0.4

Table 5. Chlorophyll a concentration (ug/L) in pond water.

D a t e	With paddle wheel aeration			Without paddle wheel aeration
1985–1986	Pond 1	Pond 2	Average	Pond 1	Pond 2	Average
9 Dec.	22.6	13.1	17.9	19.0	9.5	14.3
24 Dec.	8.3	9.5	8.9	25.0	13.1	19.1
7 Jan.	9.5	10.7	10.1	9.5	1.2	5.4
21 Jan.	18.6	11.4	15.0	15.7	17.1	16.4
4 Feb.	11.4	1.4	6.4	10.0	7.1	8.6
18 Feb.	61.4	38.6	50.0	50.0	20.0	35.0
4 Mar.	134.3	67.1	100.6	112.8	30.0	71.4
18 Mar.	219.6	151.0	185.3	158.5	153.5	156.0
2 Apr.	197.1	302.7	249.9	339.9	231.3	285.6
15 Apr.	87.1	264.2	175.7	127.1	125.7	126.4
29 Apr.	157.1	304.2	230.7	139.9	214.2	177.1
13 May	225.6	209.9	217.8	192.8	201.3	197.1
27 May	267.0	264.2	265.6	247.0	264.2	255.6
10 Jun.	134.2	298.5	216.4	58.5	211.3	134.9

Table 6. Organic matter particulate (mg/m²) in pond bottom during experimental period.

Date 1986	With Paddle Wheel aeration						Without paddle wheel aeration
	with cover			without cover			with cover			without cover
	Pond 1	Pond 2	Average	Pond 1	Pond 2	Average	Pond 1	Pond 2	Average	Pond 1	Pond 2	Average
7 Jan.	87	34	61	71	48	60	74	74	74	111	48	80
11 Feb.	178	134	156	93	102	98	115	107	111	82	98	90
11 Mar.	256	191	224	84	123	104	103	168	176	100	83	92
8 Apr.	407	314	361	42	182	112	357	291	324	175	171	173
6 May.	840	527	684	335	345	340	599	508	554	131	310	221
3 Jun.	1,002	907	955	384	526	455	825	655	740	61	35	48

Note : - Diameter of organic matter equipment 12.8 cm, depth 13.0 cm.
- Diameter of screen (cover) 0.3 – 0.5 cm.

Table 7. Total counts of macrobenthos (number/m²) in pond bottom

Treatment	16 Dec. 86	7 Jan. 86	28 Jan. 86	25 Feb. 86	25 Mar. 86	22 Apr. 86	25 May 86
With paddle wheel
Pond 1	329	3516	1385	426	337	524	2806
Pond 2	36	586	1128	400	311	240	355
Average	183	2051	1257	413	324	382	1581

Without paddle wheel	142	2984	1669	639	471	293	435
Pond 1	142	2984	1669	639	471	293	435
Pond 2	36	968	524	231	98	98	240
Average	89	1976	1097	435	285	196	338

Table 8. Features of prawn samples taken for Mean Bulk Index estimate.

			P r a w n
Sampling	Aeration	Pond	Weight		Total lenth	Standard length	Carapace length	Intestine length
(Date)	Treatment	No.	(gram)		(cm)	(cm)	(cm)	(cm)
First	With paddle	1	0.1	±0.03	2.7 ±0.28	1.9 ±0.18	1.1 ±0.16	1.2 ±0.17
07 Jan '86	wheel	2	0.2	±0.03	2.9 ±0.26	2.1 ±0.19	1.3 ±0.09	1.3 ±0.12
	Without paddle	1	0.2	±0.03	2.9 ±0.24	2.1 ±0.19	1.3 ±0.15	1.4 ±0.13
	Wheel	2	0.2	±0.09	2.7 ±0.56	1.9 ±0.39	1.1 ±0.30	1.7 ±0.66
Second	With paddle	1	3.1	±2.90	5.3 ±1.45	7.4 ±2.03	3.7 ±1.15	3.7 ±1.02
04 Mar '86	wheel	2	4.9	±2.16	6.2 ±1.12	8.7 ±1.14	4.4 ±0.71	4.3 ±0.48
	Without paddle	1	3.7	±1.34	5.9 ±0.87	7.9 ±1.04	3.9 ±0.59	4.5 ±0.54
	wheel	2	5.1	±2.70	6.4 ±0.68	8.7 ±1.04	4.3 ±0.64	4.8 ±0.80
Third	With paddle	1	40.6	±17.14	11.7 ±1.71	14.9 ±2.19	7.3 ±1.27	8.2 ±1.38
06 Jun '86	wheel	2	47.7	±21.17	11.9 ±1.75	15.6 ±2.07	7.8 ±1.14	8.3 ±1.24
	Without paddle	1	45.1	±16.83	12.0 ±1.41	15.5 ±1.75	7.5 ±0.94	8.5 ±0.97
	wheel	2	45.9	±21.56	11.8 ±1.66	15.4 ±2.15	7.7 ±1.24	8.4 ±1.63

Table 9. Mean Bulk Index and food quantity estimated to five (first and second sampling) and sixteen prawns (third sampling) during esperiment period.

Sampling Date	Aeration treatment	Pond No.	Mean Bulk Index (MBI)						Estimated feed quantity²⁾
Sampling Date	Aeration treatment	Pond No.	Pellet	Detritus	Zooplankton	Phytoplankton	Animal¹⁾	Aquatic plant	½-full	¼ - ½	empty-¼
First 7.1.86	With paddle wheel	1	1.0	7.0	4.0	2.3	5.7	7.0	-	-	-
	With paddle wheel	2	1.0	7.0	5.0	2.0	7.0	7.0	-	-	-
	Without paddle wheel	1	1.3	7.0	5.8	3.5	6.0	7.0	-	-	-
	Without paddle wheel	2	1.4	7.0	7.0	1.6	7.0	7.0	-	-	-
Second 4.3.86	With paddle wheel	1	1.0	7.0	3.3	4.3	2.7	3.7	i=1 ;s=1	-	i=4 ;s=4
	With paddle wheel	2	1.0	7.0	5.4	4.4	2.6	2.4	i=2 ;s=1	i=2 ;s=1	i=1 ;s=3
	Without paddle wheel	1	2.0	7.0	6.3	4.3	1.8	2.3	-	i=2 ;s=1	i=3 ;s=4
	Without paddle wheel	2	1.0	7.0	5.5	4.0	2.0	3.0	-	i=2	i=3 ;s=5
Third 6.6.86	With paddle wheel	1	2.1	4.9	3.6	2.6	5.4	6.6	s=2	i=10;s=2	i=6 ;s=12
	With paddle wheel	2	1.5	5.0	3.4	3.1	5.4	6.8	s=2	i=8 ;s=3	i=8 ;s=11
	Without paddle wheel	1	1.6	4.9	3.7	2.9	5.9	6.4	i=1 ;s=2	i=7 ;s=3	i=8 ;s=11
	Without paddle wheel	2	1.2	5.8	3.7	3.5	5.7	6.9	i=1	i=8 ;s=4	i=7 ;s=12

N o t e : 1) Including worms and insect
2) i : intestine, s : stomach

A). With paddle wheel aeration

B). Without paddle wheel aeration

Fig. 1. The average composition of phytoplankton abundance in the ponds with paddle wheel aeration (A) and without paddle wheel aeration (B).

A. Without paddle wheel aeration

B. With paddle wheel aeration

Fig. 2. The average composition of zooplankton abundance in ponds with paddle wheel aeration (B) and without paddle wheel aeration (A).

Fig.3. Biweekly experimental measurements of Chloiophyll a average concentration in pond with and without paddlewheel aeration.

Fig 4. Benthos abundance in bottom pond (A : each pond; B : average) with paddle wheel aeration (WP) and without paddle wheel aeration (WOP).

Fig 5. The average organic matter (mg/m²) in pond (A : with covering equipment; B : without covering equipment) with paddle wheel aeration (WP) and without paddle wheel aeration (WOP).