1,788 research outputs found
Nitrate Contamination of Groundwater and Soil Management
No full textThe Japanese Government set the environmental quality standard for nitrate (NO3) in groundwater at 10 mg N L1 in 1998, based on a level considered acceptable for avoiding infant methemoglobinemia. In 1998, 6.3% of groundwater in Japan contained NO3 exceeding 10 mg L¡¦, with agriculture regarded to be a primary source of the NO3 (Environmental Agency, Japan, 1999). This paper aims to define the mechanisms of NO3 contamination of groundwater associated with soil management in arable land.
The author gives an overview of the relation between nitrogen (N) fertilization and groundwater contamination. First of all, the utilization efficiency of N fertilizers for outdoor cultivation of vegetables is usually 50% or less (Nishio, 2001; Vance, 2001). Although N fertilizer is essential for crop production, excessive N could leach out of arable soils and eventually cause NO3 contamination of groundwater. However, conversely, excessive N is necessary as insurance in some cases, such as when there is heavy rainfall immediately after fertilization. It should be also noted that some vegetables physiologically require a high content of N in soil even at harvest.
Nitrate leaching from different fertilizers was monitored for 7 years and the data were evaluated using an N and water balance equation (Maeda et al., 2003). Excessive N from chemical fertilizers caused substantial NO3 leaching, while compost application was promising to achieve high yields and low N leaching during a few years but led to the same level of NO3 leaching as that in the plots subjected to chemical fertilizer application over longer periods of time. Thus, it is of importance to predict the N mineralization rates both for manure and for soil under natural conditions. Experimental results of this kind can provide full information on N dynamics in fields for policy decisions or regulations to reduce NO3 leaching while maintaining crop yields. Likewise, we must consider other influencing factors such as soil types, climatic conditions, and cropping systems for this purpose
Varia
No full textNotre précédent Courrier du CIBP n’a pu annoncer que par un entre filet de dernière heure le décès du Professeur Yoichi Maeda, le 22 novembre 1987. L’Académie française venait de reconnaître le rayonnement de son œuvre en lui décernant son grand prix de la francophonie. Le CIBP perd en lui un de ses membres fondateurs ; il devait lui rendre hommage au nom des pascaliens du monde entier, tous conscients de perdre en lui un maître dont les travaux font désormais partie du patrimoine commun des chercheurs et des amis de Pascal. Ayant été moi-même l’étudiant de M. Maeda à l’époque où il professait à la Sorbonne un cours sur la « méthode rédactionnelle » de Pascal d’après le manuscrit des Pensées, je garde encore le souvenir de son enseignement souriant, mais toujours précis et rigoureux, et de sa manière si féconde d’analyser les corrections et les ratures de Pascal au travail ». Jean Mesnard et M. Tetsuya Shiokawa ont bien voulu accepter d’évoquer, dans ce numéro, la mémoire du Professeur Maeda
Efficacy of laparoscopic liver resection in colorectal liver metastases and the influence of preoperative chemotherapy
No full text主査 : 住野泰清 / タイトル : Efficacy of laparoscopic liver resection in colorectal liver metastases and the influence of preoperative chemotherapy /著者 : Yoshihisa Kubota, Yuichiro Otsuka, Masaru Tsuchiya, Toshio Katagiri, Jun Ishii, Tetsuya Maeda, Akira Tamura, Hironori Kaneko /掲載誌 : World Journal of Surgical Oncology /巻号・発行年等 : 12:351, 2014 /本文ファイル: 出版者版
Effectiveness of laparoscopic subtotal cholecystectomy: Perioperative and long - term postoperative results
No full text主査 : 五十嵐良典 /タイトル : Effectiveness of laparoscopic subtotal cholecystectomy: Perioperative and long - term postoperative results /著者 : Akira Tamura, Jun Ishii, Toshio Katagiri, Tetsuya Maeda, Yoshihisa Kubota, Hironori Kaneko /掲載誌 : Hepato-Gastroenterology /巻号・発行年等 : 60 (126):1280-1283, 2013 /本文ファイル : 査読後原
Efficacy of laparoscopic liver resection in colorectal liver metastases and the influence of preoperative chemotherapy
No full text主査 : 住野泰清 / タイトル : Efficacy of laparoscopic liver resection in colorectal liver metastases and the influence of preoperative chemotherapy /著者 : Yoshihisa Kubota, Yuichiro Otsuka, Masaru Tsuchiya, Toshio Katagiri, Jun Ishii, Tetsuya Maeda, Akira Tamura, Hironori Kaneko /掲載誌 : World Journal of Surgical Oncology /巻号・発行年等 : 12:351, 2014
Effectiveness of laparoscopic subtotal cholecystectomy: Perioperative and long - term postoperative results
No full text主査: 五十嵐良典 /タイトル: Effectiveness of laparoscopic subtotal cholecystectomy: Perioperative and long - term postoperative results /著者: Akira Tamura, Jun Ishii, Toshio Katagiri, Tetsuya Maeda, Yoshihisa Kubota, Hironori Kaneko /掲載誌: Hepato-Gastroenterology /巻号・発行年等: 60 (126):1280-1283, 2013
Feasibility and technique for transvaginal natural orifice transluminal endoscopic surgery liver resection: A porcine model
No full text主査 : 岡住慎一 / タイトル : Feasibility and technique for transvaginal natural orifice transluminal endoscopic surgery liver resection: A porcine model /著者 : Toshio Katagiri, Yuichiro Otsuka, Santiago Horgan, Bryan J.Sandler, Garth R.Jacobsen, Alisa M.Coker, Masaru Tsuchiya, Tetsuya Maeda, Hironori Kaneko /掲載誌 : Surgical Laparoscopy, Endoscopy & Percutaneous Techniques /巻号・発行年等 : 27(1):e6-e11, 2017
Supplemental Material - Late-Life High Blood Pressure and Enlarged Perivascular Spaces in the Putaminal Regions of Community-Dwelling Japanese Older Persons (JPSC-AD)
No full textSupplemental Material for Late-Life High Blood Pressure and Enlarged Perivascular Spaces in the Putaminal Regions of Community-Dwelling Japanese Older Persons (JPSC-AD) by Ayumi Tachibana, Jun-ichi Iga Yasuko Tatewaki, Benjamin Thyreau, Hongkun Chen, Tomoki Ozaki, Taku Yoshida, Yuta Yoshino, Hideaki Shimizu, Takaaki Mori, Yoshihiko Furuta, Mao Shibata, Tomoyuki Ohara, Jun Hata, Yasuyuki Taki, Shigeyuki Nakaji, Tetsuya Maeda, Kenjiro Ono, Masaru Mimura, Kenji Nakashima, Minoru Takebayashi, Toshiharu Ninomiya, and Shu-ichi Ueno for the JPSC-AD study group in Journal of Geriatric Psychiatry and Neurology</p
Feasibility and technique for transvaginal natural orifice transluminal endoscopic surgery liver resection: A porcine model
No full text主査 : 岡住慎一 / タイトル : Feasibility and technique for transvaginal natural orifice transluminal endoscopic surgery liver resection: A porcine model / 著者 : Toshio Katagiri, Yuichiro Otsuka, Santiago Horgan, Bryan J.Sandler, Garth R.Jacobsen, Alisa M.Coker, Masaru Tsuchiya, Tetsuya Maeda, Hironori Kaneko / 掲載誌 : Surgical Laparoscopy, Endoscopy & Percutaneous Techniques / 巻号・発行年等 : 27(1):e6-e11, 2017 / 本文ファイル: 出版者
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