Coherent signals in the temperature and height of the sea surface off North Cape, New Zealand

1998 ◽  
Vol 32 (2) ◽  
pp. 187-202 ◽  
Author(s):  
Andrew K. Laing ◽  
Niles A. Oien ◽  
Richard Murphy ◽  
Michael J. Uddstrom
Keyword(s):  
New Zealand ◽  
Sea Surface ◽  
Coherent Signals

Diversity of tropical macroalgae in the New Zealand marine aquarium trade

2021 ◽  
Author(s):  
◽  
Kirill Woodhouse
Keyword(s):  
New Zealand ◽  
Native Species ◽  
Temperature Tolerance ◽  
Sea Surface ◽  
Aquarium Trade ◽  
Species Introduction ◽  
Molecular Barcoding ◽  
Species Introductions ◽  
Foreign Land ◽  
Negative Impacts

<p>Exotic species often slip through international borders undetected. Many perish but for some species introduction to a foreign land or sea brings release from natural enemies and a chance to establish a population. Increased global trade has increased the frequency of species introductions through stowaways and lapses in biosecurity. Once an invader is established there is the opportunity for explosive population growth at the detriment of native species and humans. The marine aquarium trade is a significant vector of species introductions, including algal introductions. The most publicized introduction from aquaria was the release of the green alga Caulerpa taxifolia from the Oceanographic Museum in Monaco. C. taxifolia introduction had large negative impacts on the invaded ecosystem.  Molecular barcoding of tropical macroalgae entering the New Zealand aquarium trade was implemented using various molecular markers (cox1, cox3, rbcL tufA, LSU). Both NCBI Blast searches and maximum-likelihood phylogenies were used to identify the isolates. A total of 62 species of tropical macroalgae were identified from coral rocks imported into New Zealand, plus samples from reef hobbyists. Some species found are known as invasive elsewhere, for example, Caulerpa cylindracea, C. racemosa, C. sertularioides, Ulva ohnoi and Chaetomorpha vieillardii. All three major groups of algae were well represented in my findings with 26 species of red algae, 24 species of green algae and 12 species of brown algae. Temperature tolerance limits are the largest determinant in survival in algae, while salinity and pH are less significant. Temperature tolerance of tropical algae to the minimum Sea Surface Temperature in Auckland (14°C) and Wellington (11°C) was tested. My results show that one species Chaetomorpha vieillardii can survive at Auckland minimum winter sea surface temperatures. Our findings have important implications for New Zealand biosecurity, as not only are a large diversity of exotic macroalgae entering the New Zealand marine aquarium trade unregulated, but there is also the potential for them to survive in New Zealand waters.   </p>

scholarly journals Planktic Foraminifera-Based Sea Surface Temperature Estimates and Late Quaternary Oceanography off New Zealand's West Coast

2021 ◽  
Author(s):  
◽  
Andrew Peter Kolodziej
Keyword(s):  
New Zealand ◽  
Surface Water ◽  
West Coast ◽  
Mass Movement ◽  
Sea Surface ◽  
Temperate Species ◽  
Tasman Sea ◽  
Modern Analogue ◽  
Neogloboquadrina Dutertrei ◽  
Glacial Periods

<p>Planktic foraminiferal assemblages were used to investigate the paleoceanography of the Eastern Tasman Sea over the last 480 kyrs (Marine Isotope Stages 12-1). One hundred and sixty-two faunas (96 picked and identified as part of this project (MIS 12-6) added to 66 census counts from Dr. M. Crundwell (MIS 6-1)) have been assembled from Marion Dufresne piston core MD06-2986 (~43˚ S. off New Zealand‟s west coast, 1477 m water depth). Faunal changes through the last five glacial-interglacial cycles are used to track surface water mass movement. Glacial periods are dominated by the eutrophic species Globigerina bulloides, with significant contributions from the temperate species Globoconella inflata. Temperate species Neogloboquadrina incompta and Gc. inflata dominate interglacials, with the former dominating the warmer parts and the latter dominating the cooler parts of the interglacials. Modern Analogue Technique (MAT) and an Artificial Neural Network (ANN) were used to estimate past sea surface temperatures (SST) based on the foraminiferal census counts data (23 species, ~46,000 specimens). SSTs show that MIS 12 was the longest, sustained cold period, while the coldest temperature was recorded in MIS 5d (~8º C). Interglacials MIS 11 and 5e are the two warmest stages of the record, with SSTs reaching ~18.5º C, about ~2º C warmer than present day. We find that contrary to either the western Tasman Sea or offshore eastern New Zealand, the eastern Tasman Sea has been fairly isolated from any major influx of subpolar or subtropical species carried in with surface water from either high or low latitude sources. Subtropical taxa abundance (Globigerinoides ruber, Neogloboquadrina dutertrei (D), Globigerinoides sacculifer, Globigerinella aequilateralis, Sphaeroidinellopsis dehiscens, Truncorotalia truncatulinoides (D), Beella digitata) is low (average ~0.6%) and only prominent during peak interglacials. Subantarctic taxa abundance (Neogloboquadrina pachyderma, Neogloboquadrina dutertrei (S)) is low (average ~5.1%), but significant, particularly in glacial periods. Comparison of faunal and SSTANN data along with ratios of Nq. pachyderma:Nq. incompta (previously referred to as coiling ratios of Nq. pachyderma) and absolute abundance of planktic productivity (a productivity proxy) suggest that the STF migrated northwards towards the site in all glacial periods, and may have moved over the site in MIS 12 and possibly MIS 5d. A latitudinal SSTANN 25 comparison between offshore eastern and western New Zealand reveals that MD06-2986 (~43º S) is most similar (~0.5º C) to ODP Site 1125 (~42º S). On the contrary, ODP Site 1119 (44º S) is ~5º C cooler than MD06-2986. This comparison highlights the significant changes in surface water masses off eastern New Zealand that exist in such a short span of latitude because of the influence of a complex submarine topography.</p>

scholarly journals Evaluating the Potential to Extract High-Resolution Paleoclimate Information from the Near-Shore New Zealand Molluscan Species Austrovenus stutchburyi

2021 ◽  
Author(s):  
◽  
Jessica J. Orsman
Keyword(s):  
Growth Rate ◽  
New Zealand ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Trace Element ◽  
Coastal Ocean ◽  
Redox Conditions ◽  
Sea Surface ◽  
Austrovenus Stutchburyi ◽  
Molluscan Species

<p>Li, B, Mg, Al, Mn, Cu, Zn, As, Sr, Ba and U/Ca ratios were measured by laser ablation inductively coupled plasma mass spectrometry for 11 modern Austrovenus stutchburyi clams to assess the potential of this molluscan species as a proxy for paleo-ocean temperature and environmental change. A. stutchburyi is an intertidal, infaunal, bivalve, widespread in New Zealand coastal regions and throughout the Quaternary-Pliocene sedimentary rock record. Five individuals from Ligar Bay and Estuary (South Island, New Zealand) were analysed to evaluate the variability between individuals calcifying in similar environmental conditions. A further six individuals were sampled from a range of latitudes (38˚ to 40˚) in the North Island, New Zealand to evaluate variability between individuals from different environments. A strong positive correlation between growth rate and Mg, Al, Mn, Sr, Ba and U/Ca ratios was observed, and a marked negative correlation was found between the same trace element/Ca ratios and ontogenetic age as growth rates slow during the molluscs' life. Thus, biological effects are the primary influence on trace element incorporation in A. stutchburyi. No clear seasonal variations were observed in the Mg and Sr/Ca ratio profiles through A. stutchburyi shells representing time periods of several years. Furthermore, for two shells for which chronologies could be reliably constructed, there were no significant correlations between Mg and Sr/Ca ratios and sea surface temperature. When Mg/Ca ratios were normalised to Sr/Ca ratios in order to eliminate the growth rate effect on trace element incorporation into the mollusc shells, some of the remaining variations appeared to visually correlate positively with sea surface temperature in several sections of a shell. However, a quantitative correlation did not confirm this (r² = 0.012). It is likely that neither Mg nor Sr incorporation into A. stutchburyi shell are primarily thermodynamically controlled. Several coincident Ba/Ca peaks in two of the Ligar Bay shells are most likely caused by environmental processes such as short periods of phytoplankton blooms or elevated seawater Ba/Ca from river flooding. Mn/Ca and U/Ca variations in A. stutchburyi from different coastal sites with different sediment characteristics appeared to be linked to the redox conditions prevailing at an open ocean sand-dominated environment (Ligar Bay) versus tidal mud flat environments (e.g. Miranda). Thus, while A. stutchburyi is unlikely to be a useful archive for past coastal ocean temperatures, it holds considerable promise for tracking past changes in coastal ocean productivity and river run-off, as well as sediment redox conditions.</p>

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