scholarly journals Mechanisms of subtropical plankton transport into the coastal waters of southern Primorye, a case of Paracalanus parvus

2016 ◽  
Vol 184 (1) ◽  
pp. 241-252
Author(s):  
Victoria V. Nadtochy ◽  
Yury I. Zuenko
Keyword(s):  
Summer Monsoon ◽  
Coastal Waters ◽  
Species Abundance ◽  
Japan Sea ◽  
Early Summer ◽  
High Abundance ◽  
Southern Primorye ◽  
Climatic Trend ◽  
Amur Bay ◽  
Paracalanus Parvus

Results of long-term studies of zooplankton species in the Amur Bay (Japan Sea) are analyzed. Two seasonal «waves» of the allochtonous species are defined: the first in the early summer that is formed mainly by inter-zonal copepods spawning in the deep layers ( Metridia pacifica , Neocalanus plumchrus, Calanus glacialis ) and the second in the late summer that is represented by warm-water copepods of subtropical origin ( Calanus pacificus and Paracalanus parvus ) obviously transported from the southern Japan Sea by currents. The latter species is able to dominate in the zooplankton community of coastal waters in the early-autumn season. Variations of this mass species abundance in the Amur Bay under changes of wind-driven upwelling/downwelling circulation are investigated using an empirical advective model of its cross-shelf transport. There is found that strong summer southern on-shore winds (summer monsoon) are favourable for its high abundance but in these conditions it is transported toward the coast by the deep compensatory flow developed only after the summer monsoon change to the winter monsoon with opposite direction; that’s why the high abundance is observed in autumn, in September-October. In the years with weak summer monsoon the species is transported to the bay in mass by the surface on-shore wind-driven flow earlier, in August, but its number decreases after the monsoon change, so the maximum of abundance is not high. Patterns of the transport by cross-shelf currents depend supposedly on the depth of plankton concentration. Recent strengthening of summer monsoon causes heightening of P. parvus abundance in the coastal waters at southern Primorye, up to extreme high values in 2013, but climatic trend of the summer monsoon intensity is negative, so decreasing of this species transport toward Primorye coast and its abundance in the coastal waters, as the Amur Bay, can be expected in the nearest future.

scholarly journals Climatic changes of temperature, salinity and nutrients in the Amur Bay of the Japan Sea

2015 ◽  
Vol 183 (4) ◽  
pp. 186-199
Author(s):  
Yury I. Zuenko ◽  
Vladimir I. Rachkov
Keyword(s):  
Summer Monsoon ◽  
Large Scale ◽  
Japan Sea ◽  
Weather Conditions ◽  
Inorganic Phosphorus ◽  
Large River ◽  
Amur Bay ◽  
Sea Bottom ◽  
Recent Climate ◽  
Climate Scale

Recent climate-scale (> 3 decades) changes of water temperature, salinity, and concentration of inorganic phosphorus, silicon and nitrogen (nitrites and nitrates) are considered for the Amur Bay where Vladivostok is located ashore. Mean seasonal values of these parameters are determined for the 1980s and 2000s. In summer, the tendencies of climatic scale are noted of SST heightening, temperature at the sea bottom lowering, and nutrients depletion in the upper layer, except of nitrate. In general, the bay becomes more stratified and less productive, on the primary trophic level, but the nitrate income, presumably from atmosphere, prevents the productivity decreasing. Links of the changes with external conditions are analyzed, and the summer monsoon weakening is defined as their main reason that determines weather conditions over Primorye and cross-shelf exchange on its shelf. These processes related with the summer monsoon present the mechanism of large-scale climate changes downscaling to meso-scale level. Besides, there is concluded that the Amur Bay is more vulnerable to marine processes than to terrestrial ones, though it is subjected to the large river discharge.

Population dynamics and reproduction ofHolothuria arenicola(Holothuroidea: Echinodermata) in coastal waters of Pakistan, North Arabian Sea

2015 ◽  
Vol 95 (6) ◽  
pp. 1245-1254 ◽  
Author(s):  
Saima Siddique ◽  
Zarrien Ayub
Keyword(s):  
Coastal Waters ◽  
Body Shape ◽  
Gonad Index ◽  
Significant Negative Correlation ◽  
Temporal Variations ◽  
Early Summer ◽  
Rocky Shores ◽  
Distribution Analysis ◽  
Autumn And Winter ◽  
Holothuria Arenicola

In Pakistan, although the sea cucumber fishery has not yet been developed,Holothuria arenicolais abundant on its coast. Nineteen months of sampling was carried out to study the population structure, allometric relationships and reproductive status ofH. arenicolastocks in Manora and Buleji rocky shores. All measured biometric characters showed significant temporal variations and width/length, weight/length, gutted weight/length and gutted weight/weight relationships followed negative allometry, indicating a change in body shape as the animal grows. Length-frequency distribution analysis was bimodal in both summer and autumn consisting of small-sized and medium-sized individuals while in winter and spring three modes were found at Manora. At Buleji, the population was unimodal in all seasons consisting of small-sized individuals. Sex inH. arenicolacannot be determined externally but can be identified on examination of gonad colour which is orange-like in females and creamy yellow in males. The sex was further confirmed on histological examination and maturation was divided into five stages, i.e. undetermined, early developing, late developing, mature and partially spawned. The sex ratio inH. arenicolawas approximately 1:1 and increase in gonad index was observed during spring and early summer, followed by a decrease in GI in autumn and winter, which showed the spawning followed by resting phase. The GI showed a significant negative correlation with salinity and non-significant correlation with temperature. There is a need to undertake more biological/ecological studies onH. arenicolain order to take effective measures for its management.

Inherent and apparent optical properties in coastal waters: a study of the Clyde Sea in early summer

2003 ◽  
Vol 56 (2) ◽  
pp. 369-376 ◽  
Author(s):  
D McKee ◽  
A Cunningham ◽  
J Slater ◽  
K.J Jones ◽  
C.R Griffiths
Keyword(s):  
Optical Properties ◽  
Coastal Waters ◽  
Early Summer ◽  
Clyde Sea

Seasonal Occurrence of Adult Carabid Beetles (Coleoptera: Carabidae) in West-Central Illinois

2020 ◽  
Vol 55 (3) ◽  
pp. 329-343
Author(s):  
Kenneth W. McCravy ◽  
Jason E. Willand
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Tallgrass Prairie ◽  
Activity Patterns ◽  
Species Abundance ◽  
Abundant Species ◽  
Early Summer ◽  
Carabid Beetles ◽  
West Central ◽  
Central Illinois

Abstract The Carabidae is a diverse family of beetles with many species of interest in conservation and biological control. Carabid beetle adult seasonal activity patterns were studied in a west-central Illinois forest/reconstructed tallgrass prairie matrix over a 2-yr period using pitfall traps. We found a threefold or greater difference in carabid abundance between years. Despite lower abundance, a second year of sampling yielded seven previously undetected species. Abundance and species richness were greatest in May–July and lower in August–October. Relative abundance and species richness were consistent among months between years. Shannon diversity and effective number of species were lowest in June and July. Cyclotrachelus sodalis (LeConte) and Chlaenius platyderus Chaudoir were the two most abundant species, comprising 54.3% of total captures. These species were most abundant in July and June, respectively. Most species showed greatest abundance in spring or early summer, and declined thereafter. Collections of several species were suggestive of bimodal seasonal patterns. Carabid species composition differed significantly among months, but not between years. Our results document seasonal variation in carabid abundance and species composition, and show that sampling throughout the growing season, and multiple sampling years, provide substantial benefits for assessments of carabid diversity in this region.

Abundance of Oil Sardine (Sardinella longiceps) and Upwelling on the Southwest Coast of India

1990 ◽  
Vol 47 (12) ◽  
pp. 2407-2419 ◽  
Author(s):  
Alan R. Longhurst ◽  
Warren S. Wooster
Keyword(s):  
Sea Level ◽  
Summer Monsoon ◽  
High Abundance ◽  
Southwest Coast Of India ◽  
Remote Forcing ◽  
Upwelled Water ◽  
Malabar Coast ◽  
Decadal Scale ◽  
Group Recruitment ◽  
Sardinella Longiceps

The abundance of oil sardine (Sardinella longiceps) on the Malabar coast is highly variable on the decadal scale. During this century there have been several periods of relatively high abundance, and several major population crashes. O-group recruitment to the fishery begins towards the end of the summer monsoon, and its success is statistically related to sea level at Cochin just prior to onset of the monsoon. At this time, sea level indicates remote forcing of upwelling, rather than the wind-driven upwelling that occurs during the monsoon. Unusually early remote-forcing appears to inhibit subsequent recruitment, perhaps through exclusion of spawning fish from the neritic zone by oxygen-deficient upwelled water.

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