EFFECT OF SOIL AMENDMENTS ON SOIL PHYSICAL ENVIRONMENT, YIELD AND GREEN HOUSE GAS EMISSIONS IN MAIZE (Zea mays L.)

Loading...
Thumbnail Image
Date
2015
Journal Title
Journal ISSN
Volume Title
Publisher
PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY, RAJENDRANAGAR, HYDERABAD
Abstract
Effect of soil amendments on soil physical environment, yield and green house gas emissions in maize (Zea mays L.) was studied with taking maize variety 900-MGOLD during rabi 2014-15 in Randomised Block Design (RBD ) with 6 treatments replicated four times at the college farm, college of agriculture, Rajendranagar. The soil was sandy loam in texture, slightly alkaline, non saline and medium in organic carbon content. The soil was low in available nitrogen and medium in available phosphorus and high in available potassium. Treatments consist of combinations of RDF and amendments (tanksilt @ 50 t ha-1, vermicompost @ 5 t ha-1, FYM @ 10 t ha-1 and biochar @ 10 t ha-1 ), Recommended Dose of Fertilizers (RDF) alone and control. Undisturbed core samples were collected for determination of bulk density, hydraulic conductivity and soil moisture at field capacity and permanent wilting point using pressure plate apparatus. Undisturbed aggregates were taken for determining aggregate stability by wet sieving method. Data on GHG emission samples were collected at regular intervals from various treatments using anchors and chambers and analysed by GC (Varian 3800) on the same day. The gravimetric soil moisture content was increased in order of tanksilt > vermicompost > biochar > FYM > RDF > control. Application of tanksilt increased moisture holding capacity of soil 2.1 to 5.6 % over control throughout growth period. The application tanksilt and vermicompost significantly increased the (AWC) available water content (2.5 and 1.48 %) respectively compared to control (9.02%). However the application of biochar, FYM and RDF resulted in AWC of (9.14, 9.43 and 9.29%) which was on par with the control. The application of different amendments tanksilt, vermicompost and FYM along with RDF significantly decreased the bulk density compared to RDF applied plots. Almost 50% increase in aggregate stability was observed with the application of tanksilt (28.92 %). Significant increase in stability of aggregates was noticed in tanksilt, vermicompost, biochar and FYM application over control (19.95 %). Application of all the amendments viz., tanksilt, vermicompost, biochar and FYM reduced hydraulic conductivity to 0.020, 0.029, 0.031 and 0.028 cm min-1 respectively over the control (0.034 cm min-1). Clay percentage was increased from 16.3 to 18.2% by application of tanksilt @ 50 t ha-1. Almost 2 % increase in clay content was observed. Application of tanksilt, vermicompost and biochar in combination with RDF resulted in significant increase of soil available NPK status. Application of all the amendments improved dry biomass and was significantly more than that of control and RDF plots. Application of amendments increased the drymatter production in the order of tanksilt > vermicompost > biochar > FYM > RDF >control. The application of tanksilt, vermicompost, biochar, FYM and RDF significantly increased the SPAD meter reading (20.69, 19.50, 15.79, 15 and 11.53) respectively compared to the control (9.73). The increase in grain yield was 33.14, 30.38, 15.94 and 10 % in tanksilt, vermicompost, biochar and FYM applied plots respectively over RDF applied plots (3547 kg ha-1). Application of tanksilt, vermicompost and biochar in combination with RDF resulted in significant increase in N content (2.50, 2.42 and 2.03) respectively in stover over the RDF (0.68%).The application of tanksilt, vermicompost and biochar in combination with RDF resulted in significant increase in P content (0.11, 0.10 and 0.09%) respectively in stover over the RDF (0.07%).The application of tanksilt, vermicompost, biochar and FYM in combination with RDF resulted in significant increase in Potassium content (1.53, 1.44,1.35 and 1.32 %) respectively in stover over the RDF (1.24%). Similar trend was observed in plant NPK uptake as that of plant NPK contents. The cumulative CO2 emissions were recorded in the order of control > vermicompost > tanksilt > FYM > RDF > biochar. The application of vermicompost, tanksilt, FYM, RDF and biochar decreased the cumulative CO2 emission (126.3, 124.4, 121.6,111.13 and 109.18 kg Co2-C ha-1) respectively compared to the control (134.12 kg Co2-C ha-1).The application of biochar, RDF, tanksilt and FYM decreased the cumulative CH4 emission (0.051, -0.041, -0.097 and -0.151 kg ha-1) respectively compared to the control (0.059 kg ha-1) but the application of vermicompost increased the cumulative CH4 emission (0.093 kg ha-1). The application of RDF, tanksilt, FYM vermicompost and biochar increased the cumulative N2O emission (1.58, 0.97, 0.78, 0.67 and 0.38 kg ha-1) respectively compared to the control ( 0.037 kg ha-1). The application of RDF, tanksilt, FYM, vermicompost and biochar increased the N2O emission factor (0.775, 0.41, 0.28, 0.243 and 0.127) respectively. Highest global warming potential was observed in the RDF and this was followed by tanksilt and lowest being the control i.e., without any fertilizer application. Among the amendments lowest global warming potential was observed in biochar application plots.
Description
Keywords
farmyard manure, vermicomposting, maize, land resources, irrigation, harvesting, fertilizers, yields, soil amendments, crops
Citation
Collections