scholarly journals Life history and population dynamics of brackish water clam, Corbicula japonica, occurring in the Kikuchi River estuary

2019 ◽  
Vol 74 (1) ◽  
pp. 1-15
Author(s):  
Hiroaki TSUTSUMI ◽  
Misato TSUJI ◽  
Tomo TATEISHI ◽  
Tomohiro KOMORITA
Author(s):  
Raveesha P ◽  
K. E. Prakash ◽  
B. T. Suresh Babu

The salt water mixes with fresh water and forms brackish water. The brackish water contains some quantity of salt, but not equal to sea water. Salinity determines the geographic distribution of the number of marshes found in estuary. Hence salinity is a very important environmental factor in estuary system. Sand is one major natural aggregate, required in construction industry mainly for the manufacture of concrete. The availability of good river sand is reduced due to salinity. The quality of sand available from estuarine regions is adversely affected due to this reason. It is the responsibility of engineers to check the quality of sand and its strength parameters before using it for any construction purpose. Presence of salt content in natural aggregates or manufactured aggregates is the cause for corrosion in steel. In this study the amount of salinity present in estuary sand was determined. Three different methods were used to determine the salinity in different seasonal variations. The sand sample collected nearer to the sea was found to be high in salinity in all methods.  It can be concluded that care should be taken before we use estuary sand as a construction material due to the presence of salinity.


Crustaceana ◽  
2021 ◽  
Vol 94 (4) ◽  
pp. 413-429
Author(s):  
Ye Ji Lee ◽  
Won Gyu Park

Abstract The population dynamics of Stenothoe valida Dana, 1852 were studied at Cheongsapo beach of Busan, Republic of Korea, from March 2019 to March 2020. Sampling was conducted once a month at low tide during spring tides. Specimens were grouped by the cephalic length at 0.025 mm intervals, and classified into four categories: females, ovigerous females, males and juveniles. The sex ratio, defined as females : total males + females, exceeded 0.5 during most of the study period. Brood size was significantly coupled with ovigerous female size. Two to four cohorts appeared at each study period. New cohorts occurred at almost every sampling except in the samples Jun-2, and Nov-2. Life span was estimated at 1-2 months. The juvenile ratio, the ratio of ovigerous females, and the recruitment rate estimated by FiSAT were commonly high in summer and winter. The life history of S. valida was not coupled with water temperature, but had a strong seasonal pattern.


2006 ◽  
Vol 58 (4) ◽  
pp. 562-566 ◽  
Author(s):  
C. Reigada ◽  
W.A.C. Godoy

The effect of larval density on the survival, fecundity and body size at two temperatures in experimental populations of C. megacephala was studied. No effect from simultaneous influence of density and temperature on life history characteristics of C. megacephala was found. Significant effects of density and temperature on survival, fecundity and body size were observed. The importance of these results for the population dynamics of C. megacephala is discussed.


2015 ◽  
Vol 737 ◽  
pp. 719-722
Author(s):  
Xiao Feng Yang ◽  
Bao Xiang Zhang ◽  
Yu Zhi Shi ◽  
Ming Yuan Fan ◽  
Hai Jiao Liu

Most of the water in yellow river estuary mixed with irrigation and leaching water, saline and brackish water, recycled water discharge into the sea without reuse except part for agriculture irrigation and aquaculture, a small part for recycling. In order to improve the efficiency and benefits of water resources utilization, this paper proposes a new way to study industrial water recycling method of the mixed water including irrigation and leaching water, saline and brackish water, recycled water. The research could have an important realistic significance to ease the contradiction between supply and demand of water resources, reduce reliance on the Yellow River and improve regional eco-environment.


Sign in / Sign up

Export Citation Format

Share Document