All issues
Volume 43 (2008)
- Issue 4 Pages 165-
- Issue 3 Pages 117-
- Issue 2 Pages 53-
- Issue 1 Pages 1-
Volume 43, Issue 2
Displaying 1-4 of 4 articles from this issue
- |<
- <
- 1
- >
- >|
Original Paper
-
Kei ISHIKAWA, Hideya KIMURA2008 Volume 43 Issue 2 Pages 53-58
Published: June 25, 2008
Released on J-STAGE: March 31, 2009
JOURNAL FREE ACCESSA 15N-tracer method was used to study the absorption of nitrogen applied in the fall to satsuma mandarin trees and Rat tail fescue, Vulpia myuros, in a pot test in which a satsuma mandarin tree was grown with the grass (Rat tail fescue) as a cover crop. Nitrogen absorption by the trees in a plot covered with Rat tail fescue was about 41% of that in the plot without cover crop. The difference of the nitrogen distribution was particularly observed in new leaves and fine roots. The absolute amount of nitrogen absorbed by the grass in a sod culture plot was about twice that absorbed by the trees in the plot, and the absorbed nitrogen was distributed in the aboveground parts in Rat tail fescue. The trees utilized 19.5% of the fall-applied nitrogen in the plot with Rat tail fescue and 48.1% in the plot without cover crop. However, total utilization (trees+grass) in the sod culture plot reached 60.9%, which was about 1.3 times the rate in the plot without a cover crop.View full abstractDownload PDF (637K)
Research Papers
-
Masafumi MITARAI, Julius Caesar V. SICAT, Osamu KINOSHITA, Yukio TOYOM ...2008 Volume 43 Issue 2 Pages 59-66
Published: June 25, 2008
Released on J-STAGE: March 31, 2009
JOURNAL FREE ACCESS -
Masafumi MITARAI, Julius Caesar V. SICAT, Osamu KINOSHITA, Yukio TOYOM ...2008 Volume 43 Issue 2 Pages 67-74
Published: June 25, 2008
Released on J-STAGE: March 31, 2009
JOURNAL FREE ACCESSThe body measurements of 76 riding tractor operators as well as the mechanical problems and operating comfort associated with their profession were investigated at the Science City of Muñoz, Nueva Ecija, Philippines in 2001-2003. As a result, the characteristic and detailed body measurements of the typical riding tractor operator in the aforementioned area in the Philippines was established. The study likewise revealed that 100% of the riding tractor operators were male with an average riding tractor operation experience of 3.3 years. The most widely used riding tractor brands were the Kubota and Iseki tractors which accounted for 63.2% and 21.1% of the total units surveyed. The average engine size was 16.6kW. The most prevalent problems mentioned by the riding tractor operators were excessive engine heat conduction, implement workmanship/durability and the need for operator cover with 86.8%, 85.5% and 59.2% ratings, respectively. Ergonomic related problems were top billed by excessive engine heat convection (86.8%), need for operator cover/protection from unfavorable weather (59.2%), and better seat design (47.4%).View full abstractDownload PDF (403K) -
Yoshinori KUNIMOTO, Manabu NISHIKAWA2008 Volume 43 Issue 2 Pages 75-82
Published: June 25, 2008
Released on J-STAGE: March 31, 2009
JOURNAL FREE ACCESSWe compared the efficiency of catching the apple snail by hand with and without trap crops. Except in the paddy rice field where there were few snails, it took over two hours per 10a to handpick the snails when a trap crop was not used. In the longest case, it took about 536 minutes per 10a. The number of snails hand picked without a trap crops was only 68.3% of the total number of snails caught. The number of snails after the first hand picking was above the control threshold for the apple snail in transplanting rice. Hand picking had to be repeated three more times to reduce the number of snails below the control threshold.
In contrast, when there were trap crops in the paddy field, it took 418 minutes per 10a to catch the snails. The number of snails remaining was much smaller than the control threshold. When trap crops were placed around a paddy field, the number of snails remaining in the paddy field after repeated picking 13 times was under the control threshold, and it took about 116 minutes per 10a. These results suggested that this method of handpicking using trap crops was easy and most efficient.View full abstractDownload PDF (677K)
- |<
- <
- 1
- >
- >|