Evolution of Soil Biochemical Parameters in Rainfed Crops: Effect of Organic and Mineral Fertilization
Table 5
Evolution of the soil biological parameters (SOM1, SOMM2, SMBC3, CO2 to ATP ratio, NO3-N) according to the fertilization treatments over the field experiment.
Soil parameter
Treatment
Sept-00
Dec-00
May-01
Sept-01
Dec-01
Feb-02
May-02
Sept-02
Dec-02
Feb-03
May-03
Average
SOM1 (g 100 g−1)
Chemical
1.23 a
1.23 a
0.99 a
1.23 a
1.31 a
1.43 a
1.43 a
1.40 a
1.25 a
1.29 a
1.31 a
1.28 a
Organic
1.17 a
1.21 a
1.01 a
1.17 a
1.28 a
1.14 b
1.17 b
1.26 a
1.35 a
1.21 a
1.12 a
1.19 b
No fertilization
1.15 a
1.12 a
1.10 a
1.14 a
1.15 a
1.27 ab
1.23 b
1.27 a
1.28 a
1.16 a
1.31 a
1.20 b
Average
1.18 AB
1.19 AB
1.03 B
1.18 AB
1.25 A
1.28 A
1.28 A
1.31 A
1.29 A
1.22 A
1.25 A
1.22
SOMM2 (μg OM g−1 15 d−1)
Chemical
739 a
280 a
260 a
200 a
253 a
260 a
334 a
304 a
380 a
412 a
520 a
358 a
Organic
793 a
259 a
281 a
174 a
257 a
241 a
282 ab
362 a
340 a
324 a
495 a
346 a
No fertilization
631 a
315 a
337 a
178 a
224 a
270 a
258 b
255 a
367 a
430 a
447 a
337 a
Average
721 A
284 DE
293 DE
184 E
245 DE
257 DE
291 DE
307 CDE
362 CD
388 C
487 B
347
SMBC3 (ATP, ng g−1)
Chemical
970 a
561 a
823 a
—
224 a
252 a
299 a
330 b
205 a
353 a
462 a
448 a
Organic
757 b
381 b
790 a
—
243 a
197 a
222 a
569 a
215 a
214 a
453 a
404 a
No fertilization
856 ab
409 b
835 a
—
248 a
265 a
265 a
391 ab
239 a
390 a
531 a
443 a
Average
861 A
450 B
816 A
—
238 C
238 C
262 C
430 B
219 C
319 C
482 B
432
CO2 to ATP ratio (μg CO2μg−1 ATP)
Chemical
4.85 a
2.61 a
1.81 a
—
7.79 a
7.41 a
7.97 a
6.81 a
13.84 a
7.82 a
7.77 a
6.87 a
Organic
6.07 a
3.73 a
2.10 a
—
7.03 a
8.25 a
8.22 a
4.42 a
10.36 a
11.61 a
7.33 a
6.91 a
No fertilization
4.60 a
3.65 a
2.28 a
—
6.05 a
7.21 a
6.53 a
4.86a a
9.29 a
8.84 a
5.86 a
5.92 a
Average
5.17 DE
3.33 EF
2.07 F
—
6.95 CD
7.62 BC
7.57 BC
5.36 D
11.16 A
9.42 AB
6.98 CD
6.57
NO3-N (ppm)
Chemical
6.2 a
9.4 a
8.3 a
35.8 a
25.3 a
23.6 a
17.4 a
15.5 a
14.6 a
14.6 a
19.3 a
17.3 a
Organic
4.6 a
9.2 a
7.6 a
32.2 a
22.0 a
15.8 a
12.3 b
12.0 a
12.2 a
11.5 a
15.5 a
14.1 b
No fertilization
4.7 a
10.4 a
7.7 a
36.5 a
17.6 a
16.8 a
12.3 b
15.7 a
13.3 a
13.1 a
17.2 a
15.0 b
Average
5.2 G
9.7 F
7.8 FG
34.8 A
21.6 B
18.7 BC
14.0 DE
14.4 DE
13.4 E
13.1 E
17.3 CD
15.5
1SOM: soil organic matter. 2SOMM: soil organic matter mineralization. 3SMBC: soil microbial biomass carbon. Different small letters in the same column for each variable indicate significant differences at . Different capital letters in the same row indicate significant differences at .