Zemsky,V.A.
Extermination of populations of commercial whale species and its possible biological consequences Technical Report
no. 268, 2005.
Abstract | BibTeX | Tags: Arabian Sea, Atlantic, Atlantic Ocean, baleen whale, baleen whales, biological consequences, cetacean, cetaceans, depletion, extermination, mammals, marine, marine mammal, Marine mammals, oil, population, populations, Southern Hemisphere, Soviet whaling, sperm whale, status, whale, whales, whaling
@techreport{,
title = {Extermination of populations of commercial whale species and its possible biological consequences},
author = {Zemsky,V.A.},
year = {2005},
date = {2005-01-01},
number = {268},
pages = {249-259},
abstract = {Cetaceans inhabit practically all seas and oceans of the world and their role in ocean biocenoses is doubtless. Being the source of nutrition and technical resources - oil, meat, etc., - this numrous group of marine mammals had also substantial meaning for the man's economic activity. In a number of coastal regions, some whales are still an important, if not one, source of protein food. All cetaceans can be subdivided into two conditional categories: those which are caught for commerial needs and those which are not. The first group comprises practically all baleen whales, the size of most of which has no analogous in terrestrial mammals, and the sperm whale - the only one of toothed whales. All other cetaceans can be referred to the second group. They are much smaller in size, but more numerous and play not less important role in biocenoses. Some of them were of commercial value in the past and now have lost it almost completely. This brief review pursues three goals: firstly, to reveal the relationship between the population number of the commercial whales and whaling in a historical aspect; secondly, to determine the significance for the estimation of the current status of the large whales' populations of the materials, pulished in 1995, on the largest falsification of statistical data on the Soviet whaling operations in the Southern Hemisphere and in some regions of the Atlantic Ocean, including the Arabian Sea and equatorial waters; thirdly, to try to reveal possible consequences of the drastic depletion of number of the large commerical whales for the ocean biogeocenoses.},
keywords = {Arabian Sea, Atlantic, Atlantic Ocean, baleen whale, baleen whales, biological consequences, cetacean, cetaceans, depletion, extermination, mammals, marine, marine mammal, Marine mammals, oil, population, populations, Southern Hemisphere, Soviet whaling, sperm whale, status, whale, whales, whaling},
pubstate = {published},
tppubtype = {techreport}
}
Cetaceans inhabit practically all seas and oceans of the world and their role in ocean biocenoses is doubtless. Being the source of nutrition and technical resources - oil, meat, etc., - this numrous group of marine mammals had also substantial meaning for the man's economic activity. In a number of coastal regions, some whales are still an important, if not one, source of protein food. All cetaceans can be subdivided into two conditional categories: those which are caught for commerial needs and those which are not. The first group comprises practically all baleen whales, the size of most of which has no analogous in terrestrial mammals, and the sperm whale - the only one of toothed whales. All other cetaceans can be referred to the second group. They are much smaller in size, but more numerous and play not less important role in biocenoses. Some of them were of commercial value in the past and now have lost it almost completely. This brief review pursues three goals: firstly, to reveal the relationship between the population number of the commercial whales and whaling in a historical aspect; secondly, to determine the significance for the estimation of the current status of the large whales' populations of the materials, pulished in 1995, on the largest falsification of statistical data on the Soviet whaling operations in the Southern Hemisphere and in some regions of the Atlantic Ocean, including the Arabian Sea and equatorial waters; thirdly, to try to reveal possible consequences of the drastic depletion of number of the large commerical whales for the ocean biogeocenoses.
Prahl,F.G.,Dymond,J.,Sparrow,M.A.
Annual biomarker record for export production in the central Arabian Sea Journal Article
In: Deep-Sea Research Part II, vol. 47, no. 200, pp. 1581-1604, 2000.
Abstract | BibTeX | Tags: Arabian Sea, depletion, marine, plankton, productivity, trap
@article{,
title = {Annual biomarker record for export production in the central Arabian Sea},
author = {Prahl,F.G.,Dymond,J.,Sparrow,M.A.},
year = {2000},
date = {2000-01-01},
journal = {Deep-Sea Research Part II},
volume = {47},
number = {200},
pages = {1581-1604},
abstract = {The record for plankton biomarkers in sediment trap samples from a one-year experiment in the central Arabian Sea (AS4: 15§59'N 61§30'E) shows variations that reflect changing biological conditions in surface waters. Particulate fluxes of C37-39 alkenones, highly branched C25 isoprenoids (HBI), dinosterol, nC28 12-hydroxy fatty acid, 24-ethylcholesterol, and C30-34 series of pentacyclic triterpanols all displayed distinct maxima at the start and stop of the Northeast (NE) and Southwest (SW) Monsoons. Surface mixing conditions changed rapidly at these times, altering light and nutrient availability, thereby triggering these biomarker signals of export production. Temporal offsets noted in individual biomarker concentrations (per g total organic carbon) at the start of the SW Monsoon suggest succession occurs in the phytoplankton community contributing to organic matter export. Comparable offsets were neither apparent at the start of the less dynamic NE Monsoon nor at the end of the NE or SW Monsoons. Broad concentration maxima for HBI also were observed at the beginning and end of the time-series during the relatively quiescent Fall Intermonsoon period when such features were conspicuously absent for other biomarkers. HBI are reputed biomarkers of Rhizoselenia and Haslea spp., two recognized dominants of diatom biomass in the Arabian Sea. These peaks in biomarker concentration could reflect either changes in the relative proportion of specific organisms that contribute to the upper ocean productivity or enhanced preservation of the biomarkers during times of high export production. In either case, the biomarker record in sediment traps reflects important changes in the biological condition of the upper ocean. All biomarkers except HBI were measurable in surface sediments deposited beneath the trap site. Comparison with concentrations in average sediment trap particles showed each was sensitive to significant ( ~ 99%) degradation, displaying depletion factors relative to TOC of ò4. Clearly, consequences of such high levels of early diagenetic recycling must be considered carefully when conclusions about changes in export production from surface waters in past oceans are drawn from stratigraphic analysis of biomarkers in marine sediments. },
keywords = {Arabian Sea, depletion, marine, plankton, productivity, trap},
pubstate = {published},
tppubtype = {article}
}
The record for plankton biomarkers in sediment trap samples from a one-year experiment in the central Arabian Sea (AS4: 15§59'N 61§30'E) shows variations that reflect changing biological conditions in surface waters. Particulate fluxes of C37-39 alkenones, highly branched C25 isoprenoids (HBI), dinosterol, nC28 12-hydroxy fatty acid, 24-ethylcholesterol, and C30-34 series of pentacyclic triterpanols all displayed distinct maxima at the start and stop of the Northeast (NE) and Southwest (SW) Monsoons. Surface mixing conditions changed rapidly at these times, altering light and nutrient availability, thereby triggering these biomarker signals of export production. Temporal offsets noted in individual biomarker concentrations (per g total organic carbon) at the start of the SW Monsoon suggest succession occurs in the phytoplankton community contributing to organic matter export. Comparable offsets were neither apparent at the start of the less dynamic NE Monsoon nor at the end of the NE or SW Monsoons. Broad concentration maxima for HBI also were observed at the beginning and end of the time-series during the relatively quiescent Fall Intermonsoon period when such features were conspicuously absent for other biomarkers. HBI are reputed biomarkers of Rhizoselenia and Haslea spp., two recognized dominants of diatom biomass in the Arabian Sea. These peaks in biomarker concentration could reflect either changes in the relative proportion of specific organisms that contribute to the upper ocean productivity or enhanced preservation of the biomarkers during times of high export production. In either case, the biomarker record in sediment traps reflects important changes in the biological condition of the upper ocean. All biomarkers except HBI were measurable in surface sediments deposited beneath the trap site. Comparison with concentrations in average sediment trap particles showed each was sensitive to significant ( ~ 99%) degradation, displaying depletion factors relative to TOC of ò4. Clearly, consequences of such high levels of early diagenetic recycling must be considered carefully when conclusions about changes in export production from surface waters in past oceans are drawn from stratigraphic analysis of biomarkers in marine sediments.