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<br/>enzymes under coconut based cropping system” was carried out during 2015-17<br/>in the Department of Soil Science and Agricultural Chemistry, College of<br/>Agriculture, Vellayani. The study was envisaged toassess the mineralization<br/>potential of soil nitrogen and carbon and to evaluate the kinetic parameters of<br/>agriculturally significant soil enzymes of coconut based cropping systems in mid<br/>laterite soils of Agro Ecological Unit (AEU) 9. Soil samples were collected from<br/>five coconut based cropping systems 1. Coconut + Fodder grass 2. Coconut +<br/>Banana, 3.Coconut + Pepper, 4. Coconut + Tuber and 5. Coconut + Vegetable<br/>under organic and conventional farming situations.<br/>With regard to physical properties, the lowest bulk density of 1.30 Mg m-3<br/>was noticed in Coconut + Vegetable under organic management. Coconut + Tuber<br/>under organic system recorded the highest value for water holding capacity (19.86<br/>%). The highest porosity was noticed under Coconut + Pepper (41.60 %) cropping<br/>system, while the interaction effects of cropping and farming systems on porosity<br/>was non significant. With regard to the electrochemical properties, the highest pH<br/>of 5.33 was noticed in Coconut + Vegetable under organic management and the<br/>lowest EC value of 0.26 dSm-1 was noticed in Coconut + Pepper and Coconut +<br/>Tuber under conventional management system.<br/>Analysis of available nutrient status revealed that the N and K status were<br/>higher in Coconut + Vegetable cropping system under conventional management<br/>viz., 326.14 kg ha-1 and 183.68 kg ha-1, while the highest value of available P<br/>(91.87 kg ha-1) was noticed in Coconut + Fodder under organic management.<br/>Among the secondary nutrients, calcium was noticed highest in Coconut +<br/>Vegetable (310.59 mg kg-1) and magnesium in Coconut + Tuber (143.49 mg kg -1)<br/>under organic management. Coconut + Banana under organic management system<br/>recorded the highest available micronutrient status of Fe, Zn, Mn and Cu viz.,<br/>45.19 mg kg-1, 1.64 mg kg-1, 23.29 mg kg-1 and 5.74 mg kg-1 respectively, while<br/>Coconut + Pepper recorded the highest boron content (1.5 mg kg -1) in the<br/>conventional management system.<br/>Coconut + Banana cropping system under organic management situation<br/>recorded the highest activities of major enzymes viz., dehydrogenase, acid<br/>phosphatase and catalase i.e., 462.52 μg of TPF released g -1 of soil 24 h-1, 80.35<br/>μg of p-nitrophenol released g -1 of soil 24 h-1 and 3.90 % of H2O2 hydrolysed g-1<br/>of soil<br/>h-1 respectively. In general, the enzyme activities were found to be the<br/>highest in organic farming situation than the conventional farming situation. In the<br/>case of β-glucosidase and amylase, Coconut + Pepper recorded the highest values<br/>viz., 4.10 μgpnp D-glucosidase g-1 soil h-1 X 10-4 and 13.82 μΜ of maltose g-1 of<br/>soil respectively.The highest values of bacterial count of 8.04 log cfu g -1 and<br/>actinomycetes count of 4.30 log cfu g -1 were noticed in Coconut + Banana under<br/>organic system of management.<br/>Enzyme activity number (EAN) was calculated using the expression EAN<br/>= 0.2{TPF+catalase (%)/10 + phenol (μg)/40 + amino-N (μg)/40 + amylase<br/>(%)/20}.The highest value for EAN was noticed in Coconut + Banana under<br/>organic system (94.01) followed by Coconut + Pepper (74.92). With respect to<br/>mineralization of soil carbon, the highest values for organic carbon, water soluble<br/>carbon and particulate organic carbon 1.63%, 72.74 mg kg -1and 0.75 %<br/>respectively were noticed for Coconut + Tuber under organic management. The<br/>highest microbial biomass carbon noticed in Coconut + Banana (15.11 mg of CO 2<br/>g-1) might have contributed to the higher enzyme activity and thus higher enzyme<br/>activity number (EAN). In the case of mineralization of soil nitrogen, Coconut +<br/>Vegetable (organic) recorded the highest value of 281.80 mg kg -1 for<br/>mineralizable nitrogen and 0.31% for total nitrogen thus contributing to14.95 %<br/>of mineralizable nitrogen to total nitrogen. From the enzyme kinetics studies, V max<br/>was found to be maximum in the 8th week for urease and acid phosphatase and 6th<br/>week for dehydrogenase.<br/>From the study, it is concluded that Coconut + Tuber and Coconut +<br/>Vegetable cropping system under organic farming situation favours the<br/>mineralization of carbon and nitrogen respectively. Coconut + Banana under<br/>organic situation was found to be the best with respect to the soil biological<br/>properties.<br/> |
| 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 | Dewey Decimal Classification |
| Item type | Theses |
| Not for loan | Collection code | Home library | Current library | 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 | 27/12/2017 | 631.4 USH/MI | 174090 | 27/12/2017 | Theses |