Search results for "Seasonal changes"
showing 3 items of 3 documents
Spatial and seasonal changes of dissolved and particulate organic C in the North Sea
2009
Sampling of the central region of the North Sea was carried out to study the spatial and seasonal changes of dissolved and particulate organic C (DOC and POC, respectively). The surface waters were collected during four cruises over a year (Autumn 2004–Summer 2005). DOC and POC concentrations were measured using high temperature catalytic oxidation methods. The surface water concentrations of DOC and POC were spatially and temporally variable. There were significantly different concentrations of DOC and POC between the inshore and offshore waters in winter and summer only, with no clear trend in autumn and spring. Highest mean concentrations of DOC were measured in spring with lower and sim…
Seasonal changes in size, sex-ratio and body condition of the damselfishChromis chromisin the central Mediterranean Sea
2014
Chromis chromisis one of the most abundant fish species on the Mediterranean rocky shores. Acting as a by-pass of nutrients from the pelagic to the rocky littoral system, it plays an important role as a resource provider and has a relevant function in the community assemblage.Chromis chromishas many of the characteristics required of an indicator species (e.g. it is easy to recognize in the field, small sized, widespread and abundant). In this study we focused on individual size, sex-ratio and body condition in a damselfish population occurring in a central Mediterranean marine protected area. Fishing trials on a monthly basis (April–November) allowed us to assess seasonal changes in popula…
Zivju sabiedrības sezonālās izmaiņas Liepājas ostas akvatorijā saimnieciskās darbības ietekmē
2021
Darbā analizēta Liepājas ostas akvatorijas zivju sabiedrība, tās sezonālās izmaiņas, un to galvenie ietekmējošie faktori. Datu ievākšana, veicot kontrolzveju ar zinātniskajiem tīkliem trīs gadu garumā, četrās sezonās (rudens, ziema, pavasaris, vasara) sniedz precīzu ieskatu par zivju sugu sezonālajām izmaiņām. Papildus ievāktie hidroloģiskie dati ļauj spriest par galvenajiem ietekmējošajiem faktoriem. Darbu vēl unikālāku padara vienā no pētījuma posmiem veiktā ostas padziļināšana, izceļot grunti, kas ļauj ne tikai novērtēt papildus faktoru ietekmi uz zivju sugu mainību, bet izdarīt secinājumus arī par saimnieciskās darbības ietekmi uz zivju sabiedrību akvatorijā, novērot ostas ekosistēmas a…