Distribution, Characterization and Dynamics of Soil enzymes in Selected Soils of Kerala (Record no. 26595)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 06397nam a2200181Ia 4500 |
| 003 - CONTROL NUMBER IDENTIFIER | |
| control field | OSt |
| 005 - DATE AND TIME OF LATEST TRANSACTION | |
| control field | 20220930153011.0 |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION | |
| fixed length control field | 140128s9999 xx 000 0 und d |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 631.4 |
| Item number | APA/DI |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Aparna B |
| 245 ## - TITLE STATEMENT | |
| Title | Distribution, Characterization and Dynamics of Soil enzymes in Selected Soils of Kerala |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc. | Vellayani |
| Name of publisher, distributor, etc. | Department Of Soil Science And Agricultural Chemistry,College Of Agriculture |
| Date of publication, distribution, etc. | 2000 |
| 502 ## - DISSERTATION NOTE | |
| Degree type | PhD |
| 520 3# - SUMMARY, ETC. | |
| Summary, etc. | Biologically and biochemically mediated processes in soils are ••• fundamental to the functioning of terrestial ecosystem. Understanding the ,A underlying biological processes in tandem with identification of indicators of ecosystem stress is inevitable to provide strategies and approaches to promote long term sustainability of the fragile ecosystem. All members of the food chain are dependent on the soil as a source of nutrients, support and sustenance besides their reliance on soil as a sink for terrestial wastes. Now there is growing evidence to believe that soil biological parameters can hold potential as early and sensitive indices of soil degradation or restoration. In this context, soil enzymes play an active role in the microbial ecology and transformations brought about by catalysing enumerable reactions in soils. The activity of soil enzymes thus hold potential as soil quality indicators though they are sensitive to temporal changes due to environmental and management factors. Thus the long term effects of soil management techniques such as crop rotation, liming, fertilization and pesticide applications on the biological regimes need detailed investigations. Hence, with the overriding objective of projecting the effects of long term fertilization, application of soil amendments and agrochemicals on enzyme activities in relation to soil fertility, the present investigation was carried out. Analysis of soil samples collected from the experimental plots of five permanent manurial trials distributed in the coastal, midland and mid-upland regions of Kerala reveal drastic differences in the activities of five major soil enzymes, viz., urease, phosphatase, protease, dehydrogenase and cellulase. It is obvious from the study of permanent manurial plots of the Rice Research Station, Kayamkulam that the activity with respect to urease, protease and cellulase is low compared to the corresponding samples collected from the long term experimental plots of Pattambi, Balaramapuram and Chethackal. The activity of phosphatase and dehydrogenase reported in this case was moderate to high compared to Pattambi and Balaramapuram. In the case of protease and cellulase the highest activity was represented by samples collected from the Central Experimental Station of the Rubber Research Institute of India, Chethackal. In general, the highest activity with respect to all enzymes studied have been reported in the intercropping experiment at the Central Experimental Station, Chethackal, representing the hilly terrain and the lowest values were seen for the permanent manurial experiment at Balaramapuram. In the permanent manurial experiments, activities of the enzymes were found to be higher in plots receiving treatments involving combinations of organic manures and chemical fertilizers. It is evident from the study that the total quantity of organic amendments added to the soil per se could not sustain a higher microbial activity coupled with a higher enzyme activity, but required supplemental addition of mineral nutrients through chemical fertilizers also. Further, the role of supplemental addition of chemical fertilizers in the enhancement of enzyme activities was very clear from the stastically significant results obtained for the permanent manurial experiment at Pattambi. Significant differences in the enzyme activities have been observed in the case of the permanent manurial experiment at Balaramapuram consequent to the main and interaction effects of chemical fertilizers at higher levels of addition especially for urease, phosphatase and dehydrogenase. Hence it is clear from the study that the application of mineral fertilizers over a basal dose of organics could enhance the microbial activity of the soil to significantly higher levels yielding higher enzyme activities even in a highly weathered low activity clay soil like the red loam soil of Balaramapuram. Enzyme activities observed were the highest under the rubber based cropping system at Chethackal followed by the rice based experiments at Pattambi and Kayamkulam while the lowest activity was noticed at Balaramapuram. Of the physico-chemical characteristics studied through path co-efficient analysis and regression analysis, OC, CEC, ~03' available N, available P, available K and respiratory activity were found to influence the enzyme activities to the maximum extent. Pot culture experiments to study the effect of amendments and agrochemicals on enzyme activities revealed significant effects due to treatments. In all these cases, the maximum inhibitory effect on enzyme activities in general, were observed consequent to the application of antibiotics followed by fungicides, insecticides and herbicides. Immediately after the application of treatments there was a decline in the enzyme activity during the active tillering, the activity gradually resumed during the panicle initiation and then decreased asymptotically towards the harvest stage. Thus it is evident from the present study that considerable suppression of the enzyme activity is observed consequent to the application of agrochemicals though it is rendered relatively harmless over a period of time within the life span of the crop. However, the long term effect of this application need to be investigated in detail. Among the various amendments used in the present study, treatment involving the application of organic amendment as vermicompost in combination with lime and fertilizers was found to be significantly superior. All the five enzymes thus registered the highest value in this treatment irrespective of the stage of the crop. |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Rajendran P (Guide) |
| 856 ## - ELECTRONIC LOCATION AND ACCESS | |
| Uniform Resource Identifier | http://krishikosh.egranth.ac.in/handle/1/5810015059 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | |
| Koha item type | Theses |
| Withdrawn status | Lost status | Source of classification or shelving scheme | Damaged status | Not for loan | Permanent Location | Current Location | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Price effective from | Koha item type |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 2014-03-18 | 631.4 APA/DI | 171652 | 2014-03-18 | 2014-03-18 | Theses |