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No.26 (1983/1) >

Title :オキナワハクセンシオマネキの日周活動と有機窒素摂取量
Title alternative :Daily Activity and Ingestion Amount of Organic Nitrogen of Uca lactea perplexa (H. Milne Edwards) (Decapoda, Ocypodidae)
Authors :仲宗根, 幸男
川, 和代
Authors alternative :Nakasone, Yukio
Kawa, Kazuyo
Issue Date :Jan-1983
Abstract :Investigations on the daily activity and ingestion amount of organic nitrogen of Uca lactea perplexa were made in the estuary of the Okukubi river, Okinawa Island, from May 1980 to January 1981. In September the crabs started activity after four to twelve minutes from the recession of the tide, while in December they began activity after about two hours. This may be due to a difference in soil or air temperatures between September and December. Active time of individuals outside burrow between emergence from burrow and subsequent descent into the burrow was on an average about three minutes in summer and about five minutes in winter. This may be related to differences in soil moisture and the rate of evaporation from the crabs' body between summer and winter. There was a correlation between organic nitrogen content and the amount of fine particles (∠O.063mm) in surface soil. Lower level (D) of habitat contained more organic nitrogen and fine particles than in upper level (A). Number of sand pellets produced by the crabs per unit time tended to decrease as their carapace width increases. Number of sand pellets produced by the crabs in the quadrat A was estimated and it was on an average 672 pellets per individual per active day. Ingestion amount of organic nitrogen was estimated using the degree of rejecting coarser particles (A=O.9583) given by Ono (1965) (Table 4).
Type Local :紀要論文
ISSN :0386-5746
Publisher :琉球大学教育学部
URI :http://hdl.handle.net/20.500.12000/8867
Citation :琉球大学教育学部紀要 第二部 no.26 p.55 -64
Appears in Collections:No.26 (1983/1)

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