Erwin Prastowo
Indonesian Coffee and Cocoa Research Insitute

Published : 2 Documents
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Ammonia Volatilization in Cocoa Farm as Affected by Sugarcane Filter Cake Supply at Different Urea and Soil Moisture Levels Prastowo, Erwin; Hikmah, Nadya Faiqotul; Baon, John Bako
Pelita Perkebunan (Coffee and Cocoa Research Journal) Vol 30, No 3 (2014)
Publisher : Indonesian Coffee and Cocoa Research Institute

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Abstract

Ammonia  (NH3)  volatilization  is  a  crucial  mechanism  in  soil  nitrogen  (N) cycle. It accounts for main loss  of N in cocoa  farms  when  environment is  suitable to  promote  the  emission.  A  research  to  locate  a  link  of  several  factors,  namely, sugarcane filter cake  (SFC), urea  and soil moisture content  to NH 3 volatilization,  and  to reveal  cocoa  N  uptake  and  urea  fertilizer  efficiency  was  taken  place  both  in  a laboratory  with  the  incubation  technique,  and  in  a  greenhouse  as  a  pot  trial. The design was completely randomized design in factorial. The soil was Inceptisol from Kaliwining Experimental Station, Jember, East Java, collected from top soil of  a  productive  cocoa  farm.  A  closed  trap  system  was  designed  to  measurevolatilized  NH 3 from  soil  and  SFC  mixture  incubated  for  14  days.  For  the  pot experiment,  cocoa  clone  of  Scavina  6  seedlings  were  grown  for  six  months  withtreatments  involving  series  level  of  SFC  and  series  level  of  urea.  Soil  moisture content influenced volatilized NH3 by reducing 50% emission in where it was more obvious in higher level of urea applied. It was more than 90% in average for the increase in volatilized NH 3roduced by increasing in level of urea from 0 to 0.4 g kg -1 in  overall  level  of  combinations. An increase in urea  level  had  resulted in increase in  soil  pH, and  Parson correlation suggested a direct  link  with  volatilized  NH 3  We found  a  relationship  between  SFC  and volatilized  NH 3 and  their combinations  with soil  moisture  and  urea  content  were  able  to  inhibit  the  emission.  Emission decrease  up  to  28%  was  observed  from  0  to  100  g  SFC  kg-1.  This  inhibition may  have contributed to  the increase in  N cocoa  plant uptake  by  more  than  70% compared  to  control  and  subsequent  increase  in  N  fertilizer  supply  efficiency up to 86%  in the combination with 0.2  g urea  kg-1.  The absence of SFC had made a decline in urea efficiency about 20 times.Keywords: ammonia volatilization, sugarcane filter cake, urea, soil moisture, cocoa
Opportunities for the application of Red-edge reflectance-based indices in coastal vegetation and agro-ecological studies Mukaromah, Laily; As-syakur, Abd. Rahman; Prastowo, Erwin
Journal of Marine and Aquatic Sciences Vol 5 No 2 (2019)
Publisher : Fakultas Kelautan dan Perikanan Universitas Udayana

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (502.195 KB) | DOI: 10.24843/jmas.2019.v05.i02.p13

Abstract

Remote sensing is an advanced tool that provides electromagnetic information about the Earth's surface and atmosphere. In ecological studies, the applications of vegetation indices (VIs) derived from remote sensing data have continued to increase, especially in capturing and monitoring vegetation properties and environmental changes. This study reviews the application of VIs with special focus on red-edge based indices in the evaluating coastal landscapes and other conservation studies. The spectral characteristics of vegetation is briefly reviewed in order to exploit the potential information of the reflectance spectrum, and the possible key role of vegetation indices in future research of coastal vegetation as well as resilience indicator in the ever-changing landscapes.