caa a22 4500 463209311 CHVBK 20180405153135.0 cr unu---uuuuu 170326e20071001xx s 000 0 eng 10.1007/s10705-007-9100-z doi (NATIONALLICENCE)springer-10.1007/s10705-007-9100-z Quantifying the effect of soil organic matter on indigenous soil N supply and wheat productivity in semiarid sub-tropical India [Elektronische Daten] [D. Benbi, Milap Chand] A field experiment was conducted on a loamy sand soil for six years to quantify the effect of soil organic matter on indigenous soil N supply and productivity of irrigated wheat in semiarid sub-tropical India. The experiment was conducted by applying different combinations of fertilizer N (0-180kgNha−1), P (0-39kgPha−1) and K (0-60kgKha−1) to wheat each year. For the data pooled over years, fertilizer N together with soil organic carbon (SOC) and their interaction accounted for 75% variation in wheat yield. The amount of fertilizer N required to attain a yield goal decreased as the SOC concentration increased indicating enhanced indigenous soil N supply with an increase in SOC concentration. Besides SOC concentration, the soil N supply also depended on yield goal. For a yield goal of 4tons ha−1, each ton of SOC in the 15cm plough layer contributed 4.75kgNha−1 towards indigenous soil N supply. An increase in the soil N supply with increase in SOC resulted in enhanced wheat productivity. The contribution of 1ton SOC ha−1 to wheat productivity ranged from 15 to 33kgha−1 across SOC concentration ranging from 3 to 9gkg-1 soil. The wheat productivity per ton of organic carbon declined curvilinearly as the native SOC concentration increased. The change in wheat productivity with SOC concentration shows that the effect of additional C sequestration on wheat productivity will depend on the existing SOC concentration, being higher in low SOC soils. Therefore, it will be more beneficial to sequester C in soils with low SOC than with relatively greater SOC concentration. In situations where the availability of organic resources for recycling is limited, their application may be preferred in soils with low SOC concentration. The results show that an increase in C sequestration will result in enhanced wheat productivity but the increase will depend on the amount of fertilizer applied and the existing fertility level of the soil. Springer Science+Business Media B.V., 2007 Carbon sequestration nationallicence N use efficiency nationallicence Nitrogen availability nationallicence Soil N supply nationallicence Wheat productivity nationallicence Benbi D. Department of Soils, Punjab Agricultural University, 141004, Ludhiana, India aut Chand Milap Department of Soils, Punjab Agricultural University, 141004, Ludhiana, India aut Nutrient Cycling in Agroecosystems Springer Netherlands 79/2(2007-10-01), 103-112 1385-1314 79:2<103 2007 79 10705 https://doi.org/10.1007/s10705-007-9100-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10705-007-9100-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Benbi D. Department of Soils, Punjab Agricultural University, 141004, Ludhiana, India aut NATIONALLICENCE 700 1- Chand Milap Department of Soils, Punjab Agricultural University, 141004, Ludhiana, India aut NATIONALLICENCE 773 0- Nutrient Cycling in Agroecosystems Springer Netherlands 79/2(2007-10-01), 103-112 1385-1314 79:2<103 2007 79 10705 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer