Effects of climate, soil and water source on determining exchangeable copper concentration in lowland paddy fields in Sri Lanka

Charuka Chandrasekara; Mojith Ariyaratne; Ranga Madushan; Upul Rathnayake; Rohana Thilakasiri; Harsha Kadupitiya; Rohana Chandrajith; Chalinda Beneragama; Lalith Suriyagoda; Charuka Chandrasekara; Mojith Ariyaratne; Ranga Madushan; Upul Rathnayake; Rohana Thilakasiri; Harsha Kadupitiya; Rohana Chandrajith; Chalinda Beneragama; Lalith Suriyagoda

doi:10.48130/cas-0024-0009

Figure 1.

(a) Box plot, (b) histogram, and (c) log transformed values of Cu concentration of paddy soil samples collected from Sri Lanka.

Figure 2.

(a) Concentration of copper (Cu) in the paddy fields used to cultivate rice in different climatic zones of Sri Lanka (Note: DZ, Dry Zone; IZ, Intermediate Zone; WZ, Wet Zone), (b) agro-climatic zones of Sri Lanka (Note: DL, Dry zone Low country; IL, Intermediate zone Low country; IM, Intermediate zone Mid country; IU, Intermediate zone Up country; WL, Wet zone Low country; WM, Wet zone Mid country), and (c) different soil orders of Sri Lanka (mean ± SE).

Figure 3.

Spatial distribution of copper (Cu) concentration in the paddy fields used to cultivate rice in different agro-climatic zones of Sri Lanka. Note: DL, Dry zone Low country; IL, Intermediate zone Low country; IM, Intermediate zone Mid country; IU, Intermediate zone Up country; WL, Wet zone Low country; WM, Wet zone Mid country.

Figure 4.

Spatial distribution of copper (Cu) concentration in the paddy fields used to cultivate rice under different soil orders of Sri Lanka.

Figure 5.

Concentration of copper (Cu) in the paddy fields used to cultivate rice in different soil orders and agro-climatic zones (ACZ) of Sri Lanka (mean ± SE). Note: DL, Dry zone Low country; IL, Intermediate zone Low country; IM, Intermediate zone Mid country; IU,Intermediate zone Up country; WL,Wet zone Low country; WM, Wet zone Mid country. Different letters over the bars, within each ACZ, indicate statistically significant difference at p < 0.05.

Figure 6.

Concentration of copper (Cu) in the paddy fields used to cultivate rice using different water sources and agro-climatic zones (ACZ) of Sri Lanka (mean ± SE). Note: DL, Dry zone Low country; IL, Intermediate zone Low country; IM, Intermediate zone Mid country; IU, Intermediate zone Up country; WL, Wet zone Low country; WM, Wet zone Mid country. Different letters over the bars, within each ACZ, indicate statistically significant difference at p < 0.05.

Figure 7.

Relationships of copper (Cu) concentration with pH of lowland paddy cultivated soils and grain yield.