Hatfield Consultants

North Vancouver, Canada

Hatfield Consultants

North Vancouver, Canada
Time filter
Source Type

Wang Y.-C.,National University of Singapore | Srivathsan A.,National University of Singapore | Feng C.-C.,National University of Singapore | Salim A.,Hatfield Consultants | Shekelle M.,Portland State University
PLoS ONE | Year: 2013

Previous studies of meta-analyses found significantly positive correlations between primate species richness and rainfall for Africa, Madagascar and the Neotropics, with the exception of Asia, leaving the open question whether that anomaly is the result of sampling bias, biogeography, or some other factor. This study re-examines the question using modelled data, with primate species richness data from the Southeast Asian Mammals Databank and rainfall data from the Climatic Research Unit. Data processing with Geographical Information Systems resulted in 390 sample points. Reduced major axis and ordinary least squares regressions were employed to examine the relationship for six regions, including the whole study area of Southeast Asia, and the subareas of Huxley West, Huxley East, Mainland Southeast Asia, Borneo, and Sumatra. The results showed a significant positive relationship between primate species richness and mean annual rainfall for Southeast Asia (r = 0.26, P<0.001). Comparing the results for the large islands and Mainland Southeast Asia showed that Sumatra had the highest correlation (r = 0.58; P<0.05). After controlling for the major biogeographic effect associated with Huxley's Line, our results showed that primate species richness is positively associated with mean annual rainfall in Southeast Asia. Our findings contrast to prior studies of meta-analyses that showed no relationship between rainfall and primate species richness in Asia, and thereby bring Asia into agreement with results showing significant positive correlations between rainfall and primate species richness everywhere else in the world. The inference is that previous anomalous results for Asia were result of sampling bias in the meta-analysis. © 2013 Wang et al.

McDonald B.G.,Golder Associates | deBruyn A.M.,Golder Associates | Elphick J.R.,Nautilus Environmental | Davies M.,Hatfield Consultants | And 2 more authors.
Environmental Toxicology and Chemistry | Year: 2010

Gametes were collected from Dolly Varden char (Salvelinus malma) from waterbodies in a region exposed to mining-related selenium (Se) releases in British Columbia, Canada. Fertilized eggs were incubated in a laboratory and deformities were assessed on newly-hatched alevins using a graduated severity index. No effects were observed on egg or alevin survival or larval weight across the studied exposure range of 5.4 to 66 mg/kg dry weight in egg. Length of some larvae was reduced at the highest egg Se concentrations and a clear residue-response relationship was observed for larval deformity. The egg concentration corresponding to a 10% increase in the frequency of deformity (EC10) was 54 mg/kg dry weight, which is substantially higher than reported for other cold-water fish species. © 2010 SETAC.

Evans M.,Environment Canada | Davies M.,Hatfield Consultants | Janzen K.,University of Saskatchewan | Muir D.,Environment Canada | And 3 more authors.
Environmental Pollution | Year: 2016

Oil sands activities north of Fort McMurray, Alberta, have intensified in recent years with a concomitant debate as to their environmental impacts. The Regional Aquatics Monitoring Program and its successor, the Joint Canada-Alberta Implementation Plan for Oil Sands Monitoring (JOSM), are the primary aquatic programs monitoring this industry. Here we examine sediment data (collected by Ekman grabs) to investigate trends and sources of polycyclic aromatic hydrocarbons (PAHs), supplementing these data with sediment core studies. Total PAH (ΣPAH) concentrations were highest at Shipyard Lake (6038 ± 2679 ng/g) in the development center and lower at Isadore's Lake (1660 ± 777 ng/g) to the north; both lakes are in the Athabasca River Valley and lie below the developments. ΣPAH concentrations were lower (622-930 ng/g) in upland lakes (Kearl, McClelland) located further away from the developments. ΣPAH concentrations increased at Shipyard Lake (2001-2014) and the Ells River mouth (1998-2014) but decreased in nearshore areas at Kearl Lake (2001-2014) and a Muskeg River (2000-2014) site. Over the longer term, ΣPAH concentrations increased in Kearl (1934-2012) and Sharkbite (1928-2010) Lakes. Further (200 km) downstream in the Athabasca River delta, ΣPAH concentrations (1029 ± 671 ng/g) increased (1999-2014) when %sands were included in the regression model; however, 50 km to the east, concentrations declined (1926-2009) in Lake Athabasca. Ten diagnostic ratios based on anthracene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, indeno[123-cd]pyrene, dibenz[a,h]anthracene, dibenzothiophene and retene were examined to infer spatial and temporal trends in PAH sources (e.g., combustion versus petrogenic) and weathering. There was some evidence of increasing contributions of unprocessed oil sands and bitumen dust to Shipyard, Sharkbite, and Isadore's Lakes and increased combustion sources in the Athabasca River delta. Some CCME interim sediment quality guidelines were exceeded, primarily in Shipyard Lake and near presumed natural bitumen sources. Crown Copyright © 2016 Published by Elsevier Ltd. All rights reserved.

Varhola A.,University of British Columbia | Wawerla J.,Simon Fraser University | Weiler M.,Albert Ludwigs University of Freiburg | Coops N.C.,University of British Columbia | And 2 more authors.
Journal of Atmospheric and Oceanic Technology | Year: 2010

Monitoring continuous changes in snowpack dynamics and its meteorological drivers is critical for understanding key aspects of water resources, climate variability, and ecology. While manual snow surveys have traditionally been used to evaluate snow processes, their high costs and discrete measurements can lead to biased estimations of accumulation and ablation rates. Ultrasonic range sensors offer an alternative to continuously monitor snow depth but their widespread employment has been limited because of high prices. This paper describes the development of an inexpensive prototype ultrasonic sensor suite characterized by a ready-to-use stand-alone design and flexibility to incorporate additional meteorological instruments. The performance of 48 units was tested during a winter season in central British Columbia, recording snow depth and air temperature data consistent with those from nearby weather stations and manual measurements. Despite a relatively small underestimation of snow depth due to known, repairable reasons, the sensor system demonstrated reliability for research and operations. © 2010 American Meteorological Society.

Elphick J.R.,Nautilus Environmental | Davies M.,Hatfield Consultants | Gilron G.,Teck Resources Ltd | Canaria E.C.,Nautilus Environmental | And 2 more authors.
Environmental Toxicology and Chemistry | Year: 2011

Elevated concentrations of sulfate occur commonly in anthropogenically impacted and natural waters. However, water quality guidelines (WQG) have not been developed in many jurisdictions, and chronic toxicity data are scarce for this anion. A variety of test organisms, including species of invertebrate, fish, algae, moss, and an amphibian, were tested for chronic toxicity to develop a robust dataset that could be used to develop WQGs. As an example of how these data might be used to establish guidelines, calculations were performed using two standard procedures: a species sensitivity distribution (SSD) approach, following methods employed in developing Canadian WQGs, and a safety factor approach, according to procedures typically used in the development of provincial WQGs in British Columbia. The interaction of sulfate toxicity and water hardness was evaluated and incorporated into the calculations, resulting in separate values for soft (10-40 mg/L), moderately hard (80-100 mg/L) and hard water (160-250 mg/L). The resulting values were 129, 644, and 725 mg/L sulfate, respectively, following the SSD approach, and 75, 625, and 675 mg/L sulfate, following the safety factor approach. © 2010 SETAC.

Ross M.S.,University of Alberta | Pereira A.D.S.,University of Alberta | Fennell J.,Integrated Sustainability Consultants Ltd. | Davies M.,Hatfield Consultants | And 3 more authors.
Environmental Science and Technology | Year: 2012

The Canadian oil sands industry stores toxic oil sands process-affected water (OSPW) in large tailings ponds adjacent to the Athabasca River or its tributaries, raising concerns over potential seepage. Naphthenic acids (NAs; CnH2n-ZO2) are toxic components of OSPW, but are also natural components of bitumen and regional groundwaters, and may enter surface waters through anthropogenic or natural sources. This study used a selective high-resolution mass spectrometry method to examine total NA concentrations and NA profiles in OSPW (n = 2), Athabasca River pore water (n = 6, representing groundwater contributions) and surface waters (n = 58) from the Lower Athabasca Region. NA concentrations in surface water (< 2-80.8 μg/L) were 100-fold lower than previously estimated. Principal components analysis (PCA) distinguished sample types based on NA profile, and correlations to water quality variables identified two sources of NAs: natural fatty acids, and bitumen-derived NAs. Analysis of NA data with water quality variables highlighted two tributaries to the Athabasca River-Beaver River and McLean Creek-as possibly receiving OSPW seepage. This study is the first comprehensive analysis of NA profiles in surface waters of the region, and demonstrates the need for highly selective analytical methods for source identification and in monitoring for potential effects of development on ambient water quality. © 2012 American Chemical Society.

Guenther S.M.,Hatfield Consultants | Gomi T.,Tokyo University of Agriculture and Technology | Moore R.D.,University of British Columbia
Hydrological Processes | Year: 2014

Stream temperature was recorded between 2002 and 2005 at four sites in a coastal headwater catchment in British Columbia, Canada. Shallow groundwater temperatures, along with bed temperature profiles at depths of 1 to 30cm, were recorded at 10-min intervals in two hydrologically distinct reaches beginning in 2003 or 2004, depending on the site. The lower reach had smaller discharge contributions via lateral inflow from the hillslopes and fewer areas with upwelling (UW) and/or neutral flow across the stream bed compared to the middle reach. Bed temperatures were greater than those of shallow groundwater during summer, with higher temperatures in areas of downwelling (DW) flow compared to areas of neutral and UW flow. A paired-catchment analysis revealed that partial-retention forest harvesting in autumn 2004 resulted in higher daily maximum stream and bed temperatures but smaller changes in daily minima. Changes in daily maximum stream temperature, averaged over July and August of the post-harvest year, ranged from 1.6 to 3°C at different locations within the cut block. Post-harvest changes in bed temperature in the lower reach were smaller than the changes in stream temperature, greater at sites with DW flow, and decreased with depth at both UW and DW sites, dropping to about 1°C at a depth of 30cm. In the middle reach, changes in daily maximum bed temperature, averaged over July and August, were generally about 1°C and did not vary significantly with depth. The pre-harvest regression models for shallow groundwater were not suitable for applying the paired-catchment analysis to estimate the effects of harvesting. However, shallow groundwater was warmer at the lower reach following harvesting, despite generally cooler weather compared to the pre-harvest year. © 2012 John Wiley & Sons, Ltd.

Guenther S.M.,Hatfield Consultants | Moore R.D.,University of British Columbia | Gomi T.,Tokyo University of Agriculture and Technology
Agricultural and Forest Meteorology | Year: 2012

This study focused on a headwater forest stream in coastal British Columbia, Canada. Air temperature, humidity and wind speed were measured at a height of 1.5. m above the stream and at a control site within a clearcut located approximately 1. km from the study stream, both before and after partial-retention forest harvesting along the stream. A specially designed evaporimeter was used to measure evaporation. Laboratory trials confirmed the reliability of evaporimeter measurements. Prior to harvesting, wind speeds were low and vapour pressure gradients above the stream were weak, leading to low rates of evaporation. Following harvesting, the decreased shading and increased ventilation over the stream led to higher wind speeds, lower vapour pressures, higher daily maximum air temperatures, higher stream temperatures and surface vapour pressures, and higher rates of evaporation. A wind function that has been used to estimate stream evaporation in a number of previous studies, but which had not been compared to measured stream evaporation, was found to overestimate evaporation. An empirical wind function fitted to the evaporimeter data differed from three others that have been derived for predicting stream evaporation in that our data did not support the inclusion of an intercept. It is hypothesized that the lack of an intercept for our data reflects the strongly stable conditions over the stream. Further research should measure stream evaporation over a broad range of streamflow and meteorological conditions, with particular attention to the role of atmospheric stability. © 2012 Elsevier B.V.

Haque M.R.,Hajee Mohammad Danesh Science and Technology University | Islam M.A.,Hajee Mohammad Danesh Science and Technology University | Wahab M.A.,Bangladesh Agricultural University | Hoq M.E.,Bangladesh Fisheries Research Institute BFRI | And 2 more authors.
Aquaculture Reports | Year: 2016

Performance of hybrid red tilapia (Mutant, Oreochromis niloticus × Oreochromis mossambicus) and GIFT tilapia strain (Oreochromis niloticus) in C/N-CP prawn (Macrobrachium rosenbergii) farming system was evaluated at the farmers' pond at Bailor union under Trishal upazilla of Mymensingh district, Bangladesh. The on-farm trial had two treatments: TR and TG (named according to the tilapia strains) with three replications. Six rectangular ponds of varying sizes (400–880 m2) were used for this experiment. Hybrid red and GIFT tilapia stains were stocked with prawn at the stocking densities of 1 tilapia fingerlings (either red or GIFT strain) and 3 prawn juveniles m-2 in both treatments. Bamboo side shoot were posted vertically as periphyton substrate. This resulted in an additional substrate surface area of 1067 m2 for periphyton development equaling 147% of the pond surface area. Considering the body weight of freshwater prawn only, feeding rates were 10% of body weight at the beginning of the study (up to 30 days), and feeding application was gradually reduced to 3% in the last month assuming 80% survival. The abundance of total benthos and periphyton as well as total periphytic biomass were significantly higher (P < 0.05) in TR than TG treatment and they were also differed significantly (P < 0.05) among different months with a decreasing trends (exception to some extent) over the experimental period. The individual harvesting weight, individual weight gain, specific growth rate, Food Conversion Ratio (FCR), survival (%), gross and net yields of prawn were similar in two treatments. In contrast, the GIFT tilapia strain showed a higher (P < 0.05) individual harvesting weight, individual weight gain, specific growth rate ((SGR, % bw d-1), survival, gross and net yields (1935 and 1825 kg ha-1, respectively) combined gross and net yields (2952 and 2784 kg ha-1, respectively), and economic return (3755 US$ with BCR 0.82) than the hybrid Red tilapia. © 2016

Uddin Md.H.,Bangladesh Agricultural University | Shahjahan Md.,Bangladesh Agricultural University | Ruhul Amin A.K.M.,Hajee Mohammad Danesh Science and Technology University | Haque Md.M.,Bangladesh Agricultural University | And 2 more authors.
Aquaculture Reports | Year: 2016

This experiment was carried out to evaluate the effect of an organophosphate pesticide, sumithion on water and sediment quality and benthic invertebrates in aquaculture ponds for 120 days. Three treatments were tried in duplicate: no sumithion (control), weekly application of 1.0 mg/L sumithion (Low dose treatment) and 2.0 mg/L sumithion (High dose treatment). Among the different water quality parameters, transparency, NO3-N and PO4-P concentrations were significantly (p < 0.05) decreased in sumithion high dose and low dose, compared to control. The pH, organic matter (%), available phosphorus (mg/L) and total nitrogen (%) of bottom-sediment also did not vary significantly (p < 0.05) among the treatments. Seven genera of benthic invertebrates belonging to Chironomidae, Oligochaeta and Mollusca were identified over the experimental period. The abundances of benthic invertebrates (number per m2) were significantly (p < 0.05) decreased in both groups treated with summation, compared to control without pesticide. The findings suggest that sumithion had adverse effect on abundance of benthic invertebrates that might have also negative impact on culture animals in aquaculture ponds. © 2016 The Authors.

Loading Hatfield Consultants collaborators
Loading Hatfield Consultants collaborators