Time filter

Source Type

Moilanen A.,University of Helsinki | Leathwick J.R.,Research and Development Group | Quinn J.M.,NIWA - National Institute of Water and Atmospheric Research
Conservation Letters | Year: 2011

We develop a high-resolution conservation prioritization analysis for New Zealand's rivers and streams that simultaneously consider both the present state (representation) of ecosystems, and the prioritization of management actions designed to mitigate ongoing human impacts on their expected future state (retention). As input we used information about the geographic distributions of river ecosystem groups and their compositional similarity, species richness, present condition as compared to their estimated pristine state, and upstream and downstream connectivity. Candidate management actions included riparian planting, establishment of wetlands on tile-drain outflows, and use of riparian buffer strips in plantation forests. The analysis, carried out at a 1-ha resolution for a study area of 22,000 km 2 in Southland, New Zealand, demonstrates a credible range of options for management intervention, particularly in lowland streams under serious threat from agricultural intensification. The proposed analysis can be replicated elsewhere for terrestrial, freshwater, or marine systems using publicly available software. ©2011 Wiley Periodicals, Inc. Source

Wouters M.,Research and Development Group
Science for Conservation | Year: 2011

The socio-economic effects of concession-based tourism on local and regional communities and economies were assessed to better inform the New Zealand Department of Conservation's (DOC's) concession management activity. A tourism inventory, in-depth interviews with concessionaires and visitor surveys were undertaken in 2004-2005 to measure concession tourism activity in Tongariro National Park (TNP), Abel Tasman National Park (ATNP) and Fiordland National Park (FNP). The net economic impact of tourism concessions was four and two times the direct impacts of the concessions themselves for TNP and ATNP, respectively. In contrast, net economic impacts were only 90% of the direct impacts for FNP. TNP contributed $30 million of direct turnover, ATNP contributed $4.6 million and FNP contributed $51 million. For every dollar of turnover generated by the concessions, a further 40 cents, 60 cents and 30 cents circulated in the economy in TNP, ATNP and FNP, respectively. Concessioned tourism was also important to employment. Tongariro concessions generated 450 FTEs (full-time equivalent jobs), each of which created another 0.3 jobs, Abel Tasman's 53 FTEs had the flow-on effect of creating an additional 0.4 jobs per FTE, and Fiordland's concessions produced 320 FTEs, leading to the generation of a further 0.2 jobs per FTE. Factors that influenced the magnitude of the effect of the concessioned product on the visitor itinerary included the composition of the gateway community, features of the region's tourism sector, park management, characteristics of the concession visitor and features of the concessioned product. It is recommended that DOC, local authorities, regional tourism organisations and the tourism industry collaborate to gather data about the role of national parks in the development of gateway communities and the regional tourism sector, and that future research includes data collection on both concession and non-concession visitor use of parks. © Copyright July 2011. Source

Innes J.,Landcare Research | Kelly D.,University of Canterbury | Overton J.M.,Landcare Research | Gillies C.,Research and Development Group
New Zealand Journal of Ecology | Year: 2010

Holdaway (1989) described three phases of historical extinctions and declines in New Zealand avifauna, the last of which (Group III, declining 1780-1986) was associated with European hunting, habitat clearance, and predation and competition from introduced European mammals. Some forest bird species have continued to decline since 1986, while others have increased, usually after intensive species-specific research and management programmes. In this paper, we review what is known about major causes of current declines or population limitation, including predation, competition for food or another resource, disease, forest loss, and genetic problems such as inbreeding depression and reduced genetic variation. Much experimental and circumstantial evidence suggests or demonstrates that predation by introduced mammals remains the primary cause of declines and limitation in remaining large native forest tracts. Predation alone is generally sufficient to explain the observed declines, but complex interactions between factors that vary between species and sites are likely to be the norm and are difficult to study. Currently, the rather limited evidence for food shortage is mostly circumstantial and may be obscured by interactions with predation. Climate and food supply determine the number of breeding attempts made by herbivorous species, but predation by introduced mammals ultimately determines the outcome of those attempts. After removal of pest mammals, populations are apparently limited by other factors, including habitat area, food supply, disease or avian predators. Management of these, and of inbreeding depression in bottlenecked populations, is likely to assist the effectiveness and resilience of management programmes. At the local or regional scale, however, forest area itself may be limiting in deforested parts of New Zealand. Without predator management, the number of native forest birds on the New Zealand mainland is predicted to continue to decline. © New Zealand Ecological Society. Source

Globacnik T.,Research and Development Group | Zalik B.,University of Maribor
Pattern Recognition | Year: 2010

This paper presents a new lossless raster font compression method that uses vertex chain code to define character's outline. Obtained chain codes are compressed by Huffman coding algorithm. The results show that the new method requires least memory space to store the raster fonts among the known methods. Moreover, the font size has almost no impact on the coder efficiency. Due to the low complexity of the decoder that occupies only 2.7 kB of memory space, this method is ideal for use in embedded systems. © 2010 Elsevier Ltd. ALL rights reserved. Source

Sarmah A.K.,Landcare Research | Rohan M.,Research and Development Group
Journal of Environmental Monitoring | Year: 2011

The performance of four mathematical models (hockey stick, biexponential, first-order double exponential decay, and first-order two-compartment) was evaluated to describe the dissipation kinetics for 4-n-nonylphenol (4-n-NP) and bisphenol-A (BPA) in groundwater-aquifer material slurry under aerobic and anaerobic conditions conducted under controlled laboratory conditions. The fit of each model to the measured values under both conditions was tested using an array of statistical indices to judge the model's ability to fit the measured datasets. Corresponding 50% (DT 50) and 90% (DT 90) dissipation values for each compound were numerically obtained and compared against each model. The model derived DT 50 values in groundwater-aquifer material ranged from 1.06 to 1.24 (4-n-NP) and 0.341 to 0.568 days (BPA) under aerobic condition, while they were 2- to 4-fold higher under anoxic condition. DT 90 values for 4-n-NP ranged anywhere between 2.3 and 4.45 days under both conditions, while DT 90 values for BPA ranged from around 1 day to as high as 12 days under both conditions tested. A visual examination of the measured and fitted plots as well as the statistical indices showed that, with the exception of the hockey stick model, the models performed satisfactorily. Despite having only 3 parameters, the biexponential model could describe the dissipation kinetics very well and this was supported by the statistical indices generated for each case. © 2011 The Royal Society of Chemistry. Source

Discover hidden collaborations