Strong seasonality in the cadmium and phosphate cycling at the subtropical convergence, south-eastern New Zealand

2020 ◽  
Vol 71 (3) ◽  
pp. 345 ◽  
Author(s):  
R. D. Frew ◽  
T. Adu ◽  
M. Gault-Ringold ◽  
A. Hamidian ◽  
K. I. Currie ◽  
...  
Keyword(s):  
Time Series ◽  
New Zealand ◽  
Trace Metals ◽  
Surface Waters ◽  
Seasonal Variability ◽  
Field Measurements ◽  
South Eastern ◽  
Phytoplankton Distribution ◽  
Characteristic Trend ◽  
Strong Seasonality

The global distribution of dissolved cadmium (Cd) in the world’s oceans is generally well understood. However, information on seasonal variability of this and other trace metals in the open ocean is difficult to obtain and, therefore, our understanding is limited. Here, we present a 3-year time series of field measurements of dissolved and particulate Cd and phosphate (PO4) from a transect across the subtropical convergence, south-eastern New Zealand. In the final year of study, the bioactive trace metals (iron, Fe; zinc, Zn; cobalt, Co) and nutrients (nitrate, NO3; silicate, Si(OH)4) were also measured to identify their influence on Cd cycling in the region. Cadmium varied seasonally from 0.009 to 0.137nM in the sub-Antarctic surface waters (SASW). Zinc in SASW varied between 0.03 and 0.011nM, which is low enough to suggest Zn limitation year-round. The seasonal input of dissolved Fe may stimulate phytoplankton growth in summer where microplankton (especially diatoms) dominate the phytoplankton distribution. The Cd:PO4 ratio also varied strongly with season (0.015×10–3 to 0.05×10–3). This seasonal variation in the Cd:PO4 ratio is productivity driven as revealed in the characteristic trend in the Cd:PO4 ratio, particulate Cd and chlorophyll-a measurements. The high seasonal variability between Cd and PO4 complicates the application of the Cd proxy for the reconstruction of historical PO4 concentrations in SASW.

Gondwanan groundwater: subterranean connections of Australian phreatoicidean isopods (Crustacea) to India and New Zealand

2008 ◽  
Vol 22 (2) ◽  
pp. 301 ◽  
Author(s):  
George D. F. Wilson
Keyword(s):  
New Zealand ◽  
Western Australia ◽  
Surface Waters ◽  
Sister Group ◽  
Morphological Data ◽  
Monophyletic Clade ◽  
South Eastern ◽  
Eastern Australia ◽  
Minimum Age ◽  
South Eastern Australia

Phreatoicidea Stebbing, 1893 live in freshwaters of Gondwana: Australia, South Africa, India and New Zealand. Many of these isopods have a subterranean lifestyle. Parsimony analysis of morphological data of generic exemplars and a Triassic fossil was used to explore the timing of this habitat adaption. The monophyly of the Hypsimetopidae Nicholls, 1943, including blind taxa Hyperoedesipus Nicholls & Milner, 1923 (Western Australia), Nichollsia Chopra and Tiwari, 1950 (Ganges Plain, India) and Phreatoicoides Sayce, 1900 (Tasmania and Victoria) was strongly supported. Crenisopus Wilson and Keable, 1999 (Kimberleys, Western Australia) and the PonderellidaeWilson & Keable, 2004 (Queensland mound springs) may be sister to hypsimetopids. Blind Phreatoicidae found only in south-eastern Australia and in New Zealand were also monophyletic. The hypogean habitat, blindness, fossil and plate tectonic evidence were mapped on the cladogram to estimate timing of this adaptation. A subterranean adaptation before 130 million years ago was supported for hypsimetopids. Phreatoicus Chilton, 1891 and Neophreatoicus Nicholls, 1944 (hypogean in New Zealand) were in a monophyletic clade with epigean Phreatoicidae, Crenoicus Nicholls, 1944 (south-eastern Australia) and Notamphisopus Nicholls, 1943 (New Zealand). Blindness in epigean taxa is consistent with recolonisation of surface waters from underground refuges. Because Crenoicus is sister-group to the New Zealand clade, and because overseas dispersal between Australia and New Zealand is unlikely, the minimum age for these blind phreatoicids is ~80 million years. This evidence is consistent with a subterranean freshwater fauna surviving the presumed Oligocene inundation of New Zealand.

Identifying Sources of Sulfate Aerosols Reaching Whiteface Mountain, NY

1985 ◽  
Vol 43 ◽  
pp. 98-101
Author(s):  
James S. Webber
Keyword(s):  
Trace Metals ◽  
Acid Deposition ◽  
Surface Waters ◽  
Dry Deposition ◽  
Coal Combustion ◽  
Public Awareness ◽  
Sulfate Aerosols ◽  
Wet And Dry Deposition ◽  
Whiteface Mountain ◽  
Toxic Trace Metals

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.

An evaluation of a strategic de-stocking regime for dairying to improve nitrogen efficiency and reduce nitrate leaching from dairy farms in nitrate-sensitive areas

2000 ◽  
pp. 105-110
Author(s):  
Cecile De Klein ◽  
Jim Paton ◽  
Stewart Ledgard
Keyword(s):  
New Zealand ◽  
Nitrate Leaching ◽  
Management Practice ◽  
Field Measurements ◽  
Dairy Farms ◽  
Nitrogen Efficiency ◽  
Management Tool ◽  
Pasture Production ◽  
Leaching Losses ◽  
Sensitive Areas

Strategic de-stocking in winter is a common management practice on dairy farms in Southland, New Zealand, to protect the soil against pugging damage. This paper examines whether this practice can also be used to reduce nitrate leaching losses. Model analyses and field measurements were used to estimate nitrate leaching losses and pasture production under two strategic de-stocking regimes: 3 months off-farm or 5 months on a feed pad with effluent collected and applied back to the land. The model analyses, based on the results of a long-term farmlet study under conventional grazing and on information for an average New Zealand farm, suggested that the 3- or 5-month de-stocking could reduce nitrate leaching losses by about 20% or 35-50%, respectively compared to a conventional grazing system. Field measurements on the Taieri Plain in Otago support these findings, although the results to date are confounded by drought conditions during the 1998 and 1999 seasons. The average nitrate concentration of the drainage water of a 5-month strategic de-stocking treatment was about 60% lower than under conventional grazing. Pasture production of the 5-month strategic de-stocking regime with effluent return was estimated based on data for apparent N efficiency of excreta patches versus uniformlyspread farm dairy effluent N. The results suggested that a strategic de-stocking regime could increase pasture production by about 2 to 8%. A cost/ benefit analysis of the 5-month de-stocking system using a feed pad, comparing additional capital and operational costs with additional income from a 5% increase in DM production, show a positive return on capital for an average New Zealand dairy farm. This suggests that a strategic destocking system has good potential as a management tool to reduce nitrate leaching losses in nitrate sensitive areas whilst being economically viable, particularly on farms where an effluent application system or a feed pad are already in place. Keywords: dairying, feed pads, nitrate leaching, nitrogen efficiency, productivity, strategic de-stocking

Measuring of time-series concentrations of nutrients in surface waters using osmotic sampler with air bubble segmentation and preservative addition

2021 ◽  
Vol 759 ◽  
pp. 143538
Author(s):  
Junxian Pei ◽  
Dongxing Yuan ◽  
Quanlong Li ◽  
Kunde Lin ◽  
Bingyan Lu ◽  
...  
Keyword(s):  
Time Series ◽  
Surface Waters ◽  
Air Bubble

The New Zealand lichen Pannaria leproloma (Nyl.) P. M. Jørg. and its panaustral relative P. farinosa nom. nov.

2007 ◽  
Vol 39 (4) ◽  
pp. 349-359 ◽  
Author(s):  
Arve ELVEBAKK ◽  
Janne FRITT-RASMUSSEN ◽  
John A. ELIX
Keyword(s):  
New Zealand ◽  
South America ◽  
High Frequency ◽  
Southern South America ◽  
South Eastern

Abstract:Pannaria leproloma is shown to be a New Zealand endemic, and is characterized by coarse isidiomorphs/isidia, a high frequency of apothecia and the presence of two cytotoxic scabrosin esters, previously unknown from Pannariaceae, and present in 40 of the samples studied. It is not a member of the Pannaria sphinctrina group, as previously thought. It has frequently been confused with a related, finely sorediate, very sparingly fertile species, which lacks scabrosin esters in more than 99 of the specimens studied. This latter species is widely distributed both in southern South America (where it is one of the most common corticolous lichens), south-eastern areas of Australia and in New Zealand. It was originally described as Psoroma isidiosum, but had to be renamed when transferred to Pannaria, and is here named Pannaria farinosa.

scholarly journals Hydrological prediction in a non-stationary world

2007 ◽  
Vol 11 (1) ◽  
pp. 408-414 ◽  
Author(s):  
R. T. Clarke
Keyword(s):  
Time Series ◽  
Urban Development ◽  
Mean Value ◽  
South American ◽  
Drainage Basins ◽  
South Eastern ◽  
Rapid Changes ◽  
Hydrological Prediction ◽  
Random Fluctuations ◽  
Linear Trends

Abstract. The paper discusses evidence that common assumptions in the analysis of hydrological time series (homogeneous variability in random fluctuations about a constant mean value) may not be appropriate for some South American drainage basins. Relatively rapid changes have occurred, and are occurring, as a consequence of replacing mature forest by short crops and urban development. Some research claims to have detected non-linear trends in streamflow in rivers draining the south-eastern part of the sub-continent, together with decadal fluctuations and interannual peaks at ENSO timescales. The paper discusses the implications of such changes for hydrological practices now in widespread and largely unquestioned use.

Effect of UVB Irradiation on Cu2+-Binding Organic Ligands and Cu2+ Speciation in Alpine Lake Waters of New Zealand

2005 ◽  
Vol 2 (1) ◽  
pp. 56 ◽  
Author(s):  
Sylvia Sander ◽  
Jonathan P. Kim ◽  
Barry Anderson ◽  
Keith A. Hunter
Keyword(s):  
New Zealand ◽  
Surface Waters ◽  
Natural Waters ◽  
Austral Summer ◽  
Organic Ligands ◽  
Conditional Stability ◽  
Uvb Radiation ◽  
Dissolved Metals ◽  
Conditional Stability Constant ◽  
Uvb Irradiation

Environmental Context. The bioavailability of dissolved metals in natural waters is directly affected by metal-sequestering agents. These agents include soil-derived matter and compounds released by microorganisms, since copper can support or inhibit aquatic microorganisms depending on concentration. During summer the levels of copper increase in surface waters, an effect intuitively attributable to increased ultraviolet light degrading the sequestering agents more effectively, leading to a concurrent release of the metal. This paper shows that the amount of degradation attributable to light is too low to explain the metal release and that a biological influence may instead be responsible. Abstract. The influence of UVB irradiation on the Cu2+ binding by natural organic ligands in six alpine lakes on the South Island, New Zealand, has been investigated using competitive ligand equilibration with salicylaldoxime and detection by cathodic stripping voltammetry (CLE-CSV). During austral summer 2002–2003 the total dissolved Cu ([Cu]T), the concentration of strong Cu2+-binding ligands ([L]T), and their conditional stability constant K´´ were determined in surface samples of all six lakes. All lakes exhibited appreciable concentrations of a strong Cu2+ binding ligand with similar K´´ values and concentrations always exceeding [CuT], thus dominating Cu2+ speciation. Four lakes (Hayes, Manapouri, Wanaka, Te Anau) showed no appreciable trend in [LT] throughout the summer, whereas in Lakes Wakatipu and Hawea [LT] increased steadily throughout this period. Laboratory UVB irradiation of lake water samples using a 400 W mercury lamp with a Pyrex glass filter (λ > 280 nm) showed that Cu2+-binding ligands are destroyed by UVB radiation, causing [L]T to decrease with a rate of –0.588 nmol L–1 h–1 (r2 0.88). From this we calculate that the in situ ligand destruction rate by UVB in summer for surface waters of these lakes is too small to significantly affect [LT], and conclude that variations in ligand concentrations must result from seasonally variable biological factors.

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