TY - JOUR
T1 - Crop yields, soil fertility and phosphorus fractions in response to long-term fertilization under the rice monoculture system on a calcareous soil
AU - Shen, J.
AU - Li, R.
AU - Fan, J.
AU - Zhang, Fusuo
AU - Tang, C.
AU - Rengel, Z.
N1 - Funding Information:
The authors thank staff of Agricultural Experimental Station in Hangu Farm, Hebei Province for technical support. The research is supported by MSBRDP (G1999011709), NNSF (30000102) of China and AusAid. The critical reviews of the manuscript made by two anonymous reviewers are gratefully acknowledged.
PY - 2004/3/10
Y1 - 2004/3/10
N2 - A 14-year field trial was conducted on a calcareous soil to evaluate the effects of continuous rice (Oryza sativa L.) cropping and fertilization on crop yield, soil fertility and phosphorus fractions. The application of N and P enhanced rice yields, while K had no yield-increasing effect because of large available soil K resource. The soil organic carbon remained at a stable level except for a decrease in the unfertilized treatment after 1988. Total N did not show clear changes with time or between treatments despite some fluctuation. The available soil K trend after 1985 as well as the comparison between treatments indicated clearly decreasing available soil K, particularly in the NP treatment. Available soil P significantly decreased in the P-omitted treatments, but remained at a stable level in the P-applied treatments with time. Of the total inorganic P (Pi), Ca phosphates (Ca-P) were the dominant Pi forms, accounting for 69-71%, followed by Fe phosphates (Fe-P), P occluded within Fe oxides (O-P) and then Al phosphates (Al-P). Of the Ca-P fractions, Ca2-P [CaHPO4·nH2O], Ca8-P [Ca8H2(PO4) 6·nH2O] and Ca10-P [Ca 10(PO4)6·(OH)2] accounted for 3.1-6.2, 5.8-6.4 and 87-91%, respectively. The NK treatment had significant Ca2-P depletion with time compared with the NPK treatment, and the similar trend was observed for Ca8-P despite decreasing Ca 8-P with time for the two treatments. In the NK treatment, Ca 2-P and Ca8-P had a good correlation with Olsen-P. The significant changes with time were not observed for Fe-P, O-P and Ca 10-P. The P application caused a weak accumulation of Fe-P, O-P and Ca10-P, but had no significant effect on total Pi over time. The results suggest that (i) P application is indispensable to maintain high yields of rice under N application and (ii) there was a substantial P release from Ca2-P and Ca8-P linked to P uptake by crops. Hence, soil indigenous P supply, P transformation and the yield responses to fertilizer P application must be synthetically considered to optimize fertilization strategies for irrigated rice production on the calcareous soil at the experimental site.
AB - A 14-year field trial was conducted on a calcareous soil to evaluate the effects of continuous rice (Oryza sativa L.) cropping and fertilization on crop yield, soil fertility and phosphorus fractions. The application of N and P enhanced rice yields, while K had no yield-increasing effect because of large available soil K resource. The soil organic carbon remained at a stable level except for a decrease in the unfertilized treatment after 1988. Total N did not show clear changes with time or between treatments despite some fluctuation. The available soil K trend after 1985 as well as the comparison between treatments indicated clearly decreasing available soil K, particularly in the NP treatment. Available soil P significantly decreased in the P-omitted treatments, but remained at a stable level in the P-applied treatments with time. Of the total inorganic P (Pi), Ca phosphates (Ca-P) were the dominant Pi forms, accounting for 69-71%, followed by Fe phosphates (Fe-P), P occluded within Fe oxides (O-P) and then Al phosphates (Al-P). Of the Ca-P fractions, Ca2-P [CaHPO4·nH2O], Ca8-P [Ca8H2(PO4) 6·nH2O] and Ca10-P [Ca 10(PO4)6·(OH)2] accounted for 3.1-6.2, 5.8-6.4 and 87-91%, respectively. The NK treatment had significant Ca2-P depletion with time compared with the NPK treatment, and the similar trend was observed for Ca8-P despite decreasing Ca 8-P with time for the two treatments. In the NK treatment, Ca 2-P and Ca8-P had a good correlation with Olsen-P. The significant changes with time were not observed for Fe-P, O-P and Ca 10-P. The P application caused a weak accumulation of Fe-P, O-P and Ca10-P, but had no significant effect on total Pi over time. The results suggest that (i) P application is indispensable to maintain high yields of rice under N application and (ii) there was a substantial P release from Ca2-P and Ca8-P linked to P uptake by crops. Hence, soil indigenous P supply, P transformation and the yield responses to fertilizer P application must be synthetically considered to optimize fertilization strategies for irrigated rice production on the calcareous soil at the experimental site.
KW - Calcareous soils
KW - Fertilizer-yield response
KW - Long-term fertilizer experiment
KW - Phosphorus fractions
KW - Rice (Oryza sativa L.)
KW - Soil nutrients
UR - http://www.scopus.com/inward/record.url?scp=1542320962&partnerID=8YFLogxK
U2 - 10.1016/j.fcr.2003.08.013
DO - 10.1016/j.fcr.2003.08.013
M3 - Article
AN - SCOPUS:1542320962
SN - 0378-4290
VL - 86
SP - 225
EP - 238
JO - Field Crops Research
JF - Field Crops Research
IS - 2-3
ER -