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Palmerston North, New Zealand

Landcare Research is one of New Zealand's Crown Research Institutes. The focus of the research at this company is the environment, biodiversity, and sustainability. Wikipedia.

Natural History Collections (NHCs) play a central role as sources of data for biodiversity and conservation. Yet, few NHCs have examined whether the data they contain is adequately representative of local biodiversity. I examined over 15,000 databased records of Hymenoptera from 1435 locations across New Zealand collected over the past 90 years. These records are assessed in terms of their geographical, temporal, and environmental coverage across New Zealand. Results showed that the spatial coverage of records was significantly biased, with the top four areas contributing over 51% of all records. Temporal biases were also evident, with a large proportion (40%) of records collected within a short time period. The lack of repeat visits to specific locations indicated that the current set of NHC records would be of limited use for long-term ecological research. Consequently, analyses and interpretation of historical data, for example, shifts in community composition, would be limited. However, in general, NHC records provided good coverage of the diversity of New Zealand habitats and climatic environments, although fewer NHC records were represented at cooler temperatures (<5°C) and the highest rainfalls (>5000 mm/yr). Analyses of NHCs can be greatly enhanced by using simple techniques that examine collection records in terms of environmental and geographical space. NHCs that initiate a systematic sampling strategy will provide higher quality data for biodiversity research than ad hoc or point samples, as is currently the norm. Although NHCs provide a rich source of information they could be far better utilised in a range of large-scale ecological and conservation studies. © 2012 Darren F. Source

For the kingdom Animalia, 1,552,319 species have been described in 40 phyla in a new evolutionary classification. Among these, the phylum Arthropoda alone represents 1,242,040 species, or about 80% of the total. The most successful group, the Insecta (1,020,007 species), accounts for about 66% of all animals. The most successful insect order, Coleoptera (387,100 species), represents about 38% of all species in 39 insect orders. Another major group in Arthropoda is the class Arachnida (112,201 species), which is dominated by the mites and ticks (Acari 54,617 species) and spiders (43,579 species). Other highly diverse arthropod groups include Crustacea (66,914 species), Trilobitomorpha (19,606 species) and Myriapoda (11,885 species). The phylum Mollusca (117,358 species) is more diverse than other successful invertebrate phyla Platyhelminthes (29,285 species), Nematoda (24,783 species), Echinodermata (20,509 species), Annelida (17,210 species) and Bryozoa (10,941 species). The phylum Craniata, including the vertebrates, represents 64,832 species (for Recent taxa, except for amphibians): among these 7,694 described species of amphibians, 31,958 species of "fish" and 5,750 species of mammals. Copyright © 2011 - Magnolia Press. Source

Tate K.R.,Landcare Research
Soil Biology and Biochemistry

Global atmospheric methane (CH4) concentrations are now approaching 1800ppbv as a result of the growing imbalance between the net CH4 emissions from natural and anthropogenic sources of this potent greenhouse gas, and its consumption by physical and biological processes. The main focus of this review is on how land-use change and soil management can be used to correct this imbalance. Currently, the main terrestrial source for CH4 is from natural wetlands and irrigated rice cultivation, although improvements in water management during rice production have resulted in major reductions of CH4 emissions from this source. Afforestation and reforestation can also enhance soil CH4 oxidation by influencing the composition and activity of the soil methanotroph (aerobic proteobacteria) community. The effects of these and other land-use changes on soil CH4 oxidation are not generally well understood, but are known to influence this process through their effects on a range of soil properties such as soil moisture, nitrogen status, and pH that also affects methanotroph community structure and function.Recent advances in molecular techniques have confirmed the central role of methanotroph communities in regulating soil CH4 consumption by revealing how they respond to land-use change. Community-level molecular analyses of methanotroph populations under different conditions now provide new insights into the distinct traits of the different subgroups and their ecology.These advances in understanding the abiotic and biological processes regulating soil CH4 oxidation now offers the possibility of being able to predict which land-use and management practices, especially for afforestation and reforestation, will achieve high soil CH4 oxidation rates They also improve the prospects for integrated assessment of the atmospheric impacts on the global greenhouse gas budget from net soil emissions of CH4, N2O, and CO2 with land use and management change. © 2014 Elsevier Ltd. Source

Dymond J.R.,Landcare Research
Earth Surface Processes and Landforms

Soil erosion in New Zealand exports much sediment and particulate organic carbon (POC) to the sea. The influence of this carbon export on carbon transfers between soils and the atmosphere has been largely unknown. Erosion models are used to estimate the net carbon transfer between soils and atmosphere due to soil erosion for New Zealand. The models are used to estimate the spatial distribution of erosion, which is combined with a digital map of soil organic carbon content to produce the spatial distribution of carbon erosion. The sequestration of atmospheric CO2 by regenerating soils is estimated by combining carbon recovery data with the age distribution of soils since erosion occurrence. The North Island of New Zealand is estimated to export 1·9 (with uncertainty of -0·5 and +1·0) million tonnes of POC per year to the sea and to sequester 1·25 (-0·3 /+0·6) million tonnes of carbon per year from the atmosphere through regenerating soils. The South Island of New Zealand is estimated to export 2·9 (-0·7/+1·5) million tonnes of POC per year and to sequester approximately the same amount. Assuming exported carbon is buried at sea with an efficiency of 80% gives New Zealand a net carbon sink of 3·1 (-2·0/+2·5) million tonnes per year; which is equivalent to 45% of New Zealand's fossil fuel carbon emissions in 1990. The net sink primarily results from a conveyor belt transfer of carbon from the atmosphere to soils regenerating from erosion to the sea floor where carbon is permanently buried. The net sink due to soil erosion can be further increased by reforestation of those terrains where erosion is excessive and there is no carbon recovery in the soils. © 2010 John Wiley & Sons, Ltd. Source

Laubach J.,Landcare Research
Agricultural and Forest Meteorology

Results from an experiment measuring methane emissions from a herd of cattle are used to investigate the performance of a backward-Lagrangian stochastic model (distributed under the name WindTrax). The availability of simultaneous mass-budget measurements of the emission rate, together with a unique setup geometry, allow to compare modelled and measured normalised concentration profiles and horizontal flux profiles with five sensor heights, z, and for four horizontal source-sensor distances, x. Simulated emission rates differ typically by 10-20% to those obtained from the mass-budget measurements, which is in agreement with previous tests of the accuracy of WindTrax. Thus, the idealisation of a herd of animals as a homogeneous area source at ground level does not seriously affect the model's applicability to infer emission rates. The profile comparison suggests that WindTrax may overestimate the speed of vertical dispersion. As a consequence, for this experiment an ideal z/. x ratio exists where the modelled emission rate is unbiased. Its value is about 0.080 in unstable and 0.067 in stable stratification. Using concentration measurements taken above or below this z/. x threshold leads to emission rates that are slightly under- or overestimated, respectively. Simultaneous measurements with an open-path methane laser are compatible with this finding. Possible causes of the apparent overestimate of vertical dispersion rates are discussed, leading to the cautious suggestion that it may stem from the choices for the Kolmogorov constant and/or the normalised dissipation rate in the model, which reflects gaps in our understanding of the atmospheric surface layer. It is argued that this notion does not contradict the earlier results from a number of controlled tracer-release experiments that had been designed to test WindTrax. © 2010 Elsevier B.V. Source

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