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Kerala Agricultural University, Thrissur

The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively. Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively. On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs. In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc. During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU). Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.

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20221
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Subject: Soil Science and Agriculture Chemistry × Author: Anju, Sajan × End date: 2022 × Start date: 2022 × Type: Thesis ×
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    ThesisItemOpen Access
    Effect of salinity on carbon mineralisation under different land uses in Pokkali ecosystem
    (Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellanikkara, 2022) Anju, Sajan; KAU; Sreelatha, A K
    Soil forms the largest storehouse for terrestrial organic carbon, encompassing approximately two-thirds of the carbon in the ecosystem. This plays a pivotal role in reducing atmospheric CO2 and combating global warming and related concerns. Differences in land use have a considerable effect on soil organic carbon pools and fluxes. Mineralisation of soil organic carbon enhances CO2 emission into the atmosphere and salinity of soil can affect the rate of this process. In this context, an investigation was carried out with the objective to study the effect of salinity on carbon mineralisation under different land uses in Pokkali ecosystem. The study was conducted by collecting georeferenced surface soil samples (0- 20 cm) from three land uses of Pokkali ecosystem namely rice-prawn, rice alone and prawn alone from Kumbalangi, RRS, Vyttila and Kadamakkudy respectively. The samples were analyzed for different soil properties such as pH, electrical conductivity (EC), particle size, cation exchange capacity, bulk density and estimated soil organic carbon pools such as soil organic carbon, labile carbon, water soluble carbon and microbial biomass carbon. Soil organic carbon stocks and dehydrogenase activity were also estimated as per standard procedures. Carbon mineralisation was studied by a laboratory incubation experiment for 74 days where two sets of soil (with and without 1% paddy straw) was amended with different concentrations of CaSO4 and Na2SO4 alone or both in combinations of 40 and 80 mmol per kg soil in order to get the desired change in electrical conductivity similar to field conditions. The mean pH registered for rice-prawn, rice alone and prawn alone land uses were under neutral range and mean EC were less than 4 dS m-1. Soil texture of rice-prawn and rice alone belonged to clay and prawn alone in sandy clay loam class. Cation exchange capacity was highest in rice-prawn and lowest in prawn alone land use. The highest mean bulk density was observed in prawn alone and the lowest in rice-prawn land uses. The results revealed that rice-prawn land use recorded the highest organic carbon pools and prawn alone land use recorded the lowest organic carbon pools. Rice-prawn land use recorded higher content of soil organic carbon, labile carbon, water soluble carbon, microbial biomass carbon and total carbon followed by rice alone land use due to abundance of organic matter in these soils. The maximum soil organic carbon stock was recorded in rice alone (26.46 Mg ha -1) and minimum in rice-prawn (22.53 Mg ha -1) land use. The maximum dehydrogenase activity was recorded from rice alone (2959.697 µg TPF h-1 g-1) and the lowest from prawn alone (2132.491 µg TPF h-1 g-1) land uses. Carbon mineralisation study revealed that CO2 evolved from soil decreased with time. The maximum CO2 was evolved on day 11 for rice-prawn and prawn alone land uses and day 17 for rice alone land use and declined steadily thereafter. The maximum cumulative CO2 was recorded from the treatments other than control (without paddy straw and salts). The lowest mean cumulative CO2 in the control was recorded from rice- prawn (7.2 mg 100 g-1) land use and the highest recorded from prawn alone (26.48 mg 100 g-1) followed by rice alone (25.15 mg 100 g-1) land uses. A significant positive correlation was observed between pH, dehydrogenase activity and total organic carbon with cumulative CO2 in all land uses. After 74 days of incubation study, the pH of control was reduced and that of other treatments (with paddy straw and salts) was increased in all land uses. The EC of the treatments with salts amendments were more than 4 dS m-1 in all land uses before the start of incubation. After the incubation period, EC decreased in all salt amendments of different land uses and increased in treatments without salt amendments. Dehydrogenase activity and total carbon were found higher in the treatments with paddy straw and salts than in control. Relatively higher dehydrogenase activity was recorded in rice-prawn land use followed by prawn alone and rice alone land uses. The EC was positively correlated with dehydrogenase activity which stimulated carbon mineralisation in these soils. In these land uses, there was no discernible difference between paddy straw and salt amended treatments with respect to carbon mineralisation. Both the dehydrogenase activity and the total carbon content contributed to carbon mineralisation process. In Pokkali ecosystems, rice-prawn land use recorded the highest soil organic carbon pools and the lowest carbon mineralisation, indicating the existence of an environment that is conducive for building organic carbon which is crucial for sequestering more carbon into these soils. As the salinity increased carbon mineralisation was also increased. The rice cultivation in the low saline phase reduces salinity by leaching out the accumulated salts, whereas prawn farming does not. Therefore, prawn alone land use remains saline throughout the year, resulting in increased carbon mineralisation and decreased carbon sequestration. This study emphasizes the importance of integrated rice-prawn farming systems in Pokkali lands to maintain soil quality and slow down the global warming through increased carbon sequestration.