Nutrients, Toxins and Pollutants - The Biogeochemistry of Submerged Soils - page 223

1 − 2

Organic C content (%) SW

45
44
43
42
41

2 − 3

3 − 4

< 1 4 − 5

3 4

−

< 1

Depth of observation

CaCO 3 content (%)

45
44
43
42
41

2.5 − 3.5

1.5 − 2.5

0.5 − 1.5

3.5 − 4 < 0.5

< 0.5

Extent of Zn deficiency

Zn deficiency
(weak, moderate, strong, very strong)
Experimental fields

No rice grown
(shrubs and grasses)

Zn deficiency
(strong, weak, none)

45
44
43
42
41

Artesian well

0 100 200 300 400 m

Figure 7.6 Toposequence at Tiaong, Quezon Province, Philippines, showing extreme Zn deficiency in rice (van Breemen et al ., 1980).
Reproduced by permission of Kluwer Academic Publishers