Nandi, R.Mukherjee, S.Ghatak, P.Kundu, A.Mukherjee, D.Bandyopadhyay, P. K.2020-09-242020-09-242020-04Nandi R., Mukherjee S., Ghatak P., Kundu A., Mukherjee D., Bandyopadhyay P. K.. Aggregates Characterization and Its Associated Organic Carbon in Two Contrasting Lowland Rice Soils of West Bengal. International Journal of Environment and Climate Change. 2020 Apr; 10(4): 14-232581-8627http://imsear.searo.who.int/handle/123456789/204855Aims: The present study investigated the effect of lowland rice soils of two regions viz. new alluvial and red-laterite on aggregate characterization and their associated organic carbon (SOC). Study Design: Randomized block design (RBD). Place and Duration of Study: New alluvial soils were collected from Jangipara block of Hooghly, West Bengal and Red-laterite soils were collected from Raghunathpur block of Purulia, West Bengal during 2017-18. Methodology: For each soil types (New alluvial and Red-laterite) five locations were identified and soil samples were collected from three depths i.e. 0-10, 10-20 and 20-30 cm. The aggregate characteristics i.e. water-stable aggregates (WSAs), mean weight diameter (MWD), aggregate stability and aggregate size fractions along with the distribution of carbon in those aggregate size fractions were critically studied. Results: The aggregate size as well as the stability decreased with increasing soil depth from 0 to 30 cm in both soils. New alluvial soils showed higher aggregate stability than red-laterite soils. Mean weight diameter (MWD) values of new alluvial soils were 34, 29 and 87% more than red-laterite soils at 0-10, 10-20 and 20-30 cm depth, respectively. Presence of higher amount of clay and organic matter in new alluvial made the difference in structural coefficient. The surface soil (0-10 cm) had more coarse aggregate (Cmac A >2000μ) fraction, however, microaggregates (<250μ) were dominant in lower depths in both soils. Water stable aggregates (WSA) in surface soils of new alluvial and red-laterite were 57 and 36%, respectively and were decreased with depth. Red-laterite produced higher micro aggregates as compared to new alluvial soils. Coarse macro aggregate fractions (>2000μ) retained maximum amount of soil organic carbon in both soils however, coarse micro aggregate associated carbon (Cmic AC<250μ) was captured in lower depths. New alluvial soils yielded aggregates with higher in diameter and stability coefficient that is due to higher amount of carbon stored in aggregates. Conclusion: The abundance of macro aggregate of New alluvial soils indicates better soil physical quality than Red-laterite soil which was dominated in higher micro aggregates leads to poor in structure and susceptible to water erosion.Water-stable aggregatesmean weight diameteraggregate stabilityaggregate size fractionsaggregate associated carbonJournal ArticleIndiaDepartment of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, India.Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, India.Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, India.Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, India.Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, India.Department of Agricultural Chemistry and Soil Science, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, 741252, India.