Mineralization of soil nitrogen, carbon and kinetics of enzymes under coconut based cropping system (Record no. 157957)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 05099nam a22001697a 4500 |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 631.4 |
| Item number | USH/MI |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Usharani K V |
| 245 ## - TITLE STATEMENT | |
| Title | Mineralization of soil nitrogen, carbon and kinetics of enzymes under coconut based cropping system |
| 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 | 2017 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | 125p |
| 502 ## - DISSERTATION NOTE | |
| Dissertation note | MSc |
| 520 3# - SUMMARY, ETC. | |
| Abstract | A study entitled “Mineralization of soil nitrogen, carbon and kinetics of enzymes under coconut based cropping system” was carried out during 2015-17 in the Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani. The study was envisaged toassess the mineralization potential of soil nitrogen and carbon and to evaluate the kinetic parameters of agriculturally significant soil enzymes of coconut based cropping systems in mid laterite soils of Agro Ecological Unit (AEU) 9. Soil samples were collected from five coconut based cropping systems 1. Coconut + Fodder grass 2. Coconut + Banana, 3.Coconut + Pepper, 4. Coconut + Tuber and 5. Coconut + Vegetable under organic and conventional farming situations. With regard to physical properties, the lowest bulk density of 1.30 Mg m-3 was noticed in Coconut + Vegetable under organic management. Coconut + Tuber under organic system recorded the highest value for water holding capacity (19.86 %). The highest porosity was noticed under Coconut + Pepper (41.60 %) cropping system, while the interaction effects of cropping and farming systems on porosity was non significant. With regard to the electrochemical properties, the highest pH of 5.33 was noticed in Coconut + Vegetable under organic management and the lowest EC value of 0.26 dSm-1 was noticed in Coconut + Pepper and Coconut + Tuber under conventional management system. Analysis of available nutrient status revealed that the N and K status were higher in Coconut + Vegetable cropping system under conventional management viz., 326.14 kg ha-1 and 183.68 kg ha-1, while the highest value of available P (91.87 kg ha-1) was noticed in Coconut + Fodder under organic management. Among the secondary nutrients, calcium was noticed highest in Coconut + Vegetable (310.59 mg kg-1) and magnesium in Coconut + Tuber (143.49 mg kg -1) under organic management. Coconut + Banana under organic management system recorded the highest available micronutrient status of Fe, Zn, Mn and Cu viz., 45.19 mg kg-1, 1.64 mg kg-1, 23.29 mg kg-1 and 5.74 mg kg-1 respectively, while Coconut + Pepper recorded the highest boron content (1.5 mg kg -1) in the conventional management system. Coconut + Banana cropping system under organic management situation recorded the highest activities of major enzymes viz., dehydrogenase, acid phosphatase and catalase i.e., 462.52 μg of TPF released g -1 of soil 24 h-1, 80.35 μg of p-nitrophenol released g -1 of soil 24 h-1 and 3.90 % of H2O2 hydrolysed g-1 of soil h-1 respectively. In general, the enzyme activities were found to be the highest in organic farming situation than the conventional farming situation. In the case of β-glucosidase and amylase, Coconut + Pepper recorded the highest values viz., 4.10 μgpnp D-glucosidase g-1 soil h-1 X 10-4 and 13.82 μΜ of maltose g-1 of soil respectively.The highest values of bacterial count of 8.04 log cfu g -1 and actinomycetes count of 4.30 log cfu g -1 were noticed in Coconut + Banana under organic system of management. Enzyme activity number (EAN) was calculated using the expression EAN = 0.2{TPF+catalase (%)/10 + phenol (μg)/40 + amino-N (μg)/40 + amylase (%)/20}.The highest value for EAN was noticed in Coconut + Banana under organic system (94.01) followed by Coconut + Pepper (74.92). With respect to mineralization of soil carbon, the highest values for organic carbon, water soluble carbon and particulate organic carbon 1.63%, 72.74 mg kg -1and 0.75 % respectively were noticed for Coconut + Tuber under organic management. The highest microbial biomass carbon noticed in Coconut + Banana (15.11 mg of CO 2 g-1) might have contributed to the higher enzyme activity and thus higher enzyme activity number (EAN). In the case of mineralization of soil nitrogen, Coconut + Vegetable (organic) recorded the highest value of 281.80 mg kg -1 for mineralizable nitrogen and 0.31% for total nitrogen thus contributing to14.95 % of mineralizable nitrogen to total nitrogen. From the enzyme kinetics studies, V max was found to be maximum in the 8th week for urease and acid phosphatase and 6th week for dehydrogenase. From the study, it is concluded that Coconut + Tuber and Coconut + Vegetable cropping system under organic farming situation favours the mineralization of carbon and nitrogen respectively. Coconut + Banana under organic situation was found to be the best with respect to the soil biological properties. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Soil Science and Agricultural Chemistry |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Aparna, B (Guide) |
| 856 ## - ELECTRONIC LOCATION AND ACCESS | |
| Uniform Resource Identifier | http://krishikosh.egranth.ac.in/handle/1/5810143086 |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | |
| Item type | Theses |
| Not for loan | Collection code | Permanent location | Current location | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Koha item type |
|---|---|---|---|---|---|---|---|---|---|
| Not For Loan | Reference Book | KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 2017-12-27 | 631.4 USH/MI | 174090 | 2017-12-27 | Theses |