Ion Export from a Small British Columbia Watershed After Forest Harvesting

2007 ◽  
Vol 42 (3) ◽  
pp. 162-171 ◽  
Author(s):  
Richard N. Nordin ◽  
Zhanxue Zhu ◽  
Asit Mazumder

Abstract A small coastal British Columbia lake was monitored before and after approximately 11% of the watershed was logged. There was an increase in the concentrations of most of the ions measured in the lake water after logging. Peak concentrations occurred two to three years after logging and most ions returned to background concentrations in five to eight years. Two methods were used to estimate the increased export of ions resulting from the forest harvesting. The first method used a water chemistry / hydrology watershed model, and the second used the changes in lake concentrations to calculate watershed input. The changes in ion concentrations and export varied with model and chemistry parameter with a change from a 1.3- to 4.2-fold increase for major cations and anions like calcium, magnesium, sodium, and chloride, to a 5- to 35-fold increase in ion export for nitrate and ammonium. The export of nitrogen from the watershed has implications for both water quality and future forest productivity. The measurement of lake ion increase is proposed as a general means of evaluating longer term change or disturbance in a watershed.

2001 ◽  
Vol 58 (3) ◽  
pp. 492-505 ◽  
Author(s):  
Kathleen Laird ◽  
Brian Cumming

The impact of forest harvesting on lakes within the central interior of British Columbia was examined in a paleolimnological study of six lakes that had 28–82% of their watersheds clear-cut (impact lakes) and four lakes that had experienced no logging in their watersheds (reference lakes). Changes in diatom species composition and percent organic matter in 210Pb-dated sediment cores were compared over the last 80 years in each of the impact lakes before and after the onset of forest harvesting and, in the reference lakes, before and after 1960 (the average onset of logging in five of the six impact lakes) and before and after 1975 (the onset of logging in one impact lake). Significant changes in species composition of diatoms following forest-harvesting activities were detected in four of the impact lakes and three of the reference lakes; however, the changes in diatom species composition were small, with changes in the relative abundance of the most common species being at most 11%. Significant increases in the percent organic matter after 1960 were found in one impact lake and three reference lakes; again these changes were small, with increases of 2–5%.


1996 ◽  
Vol 76 (2) ◽  
pp. 153-164 ◽  
Author(s):  
B. J. Zebarth ◽  
J. W. Paul ◽  
O. Schmidt ◽  
R. McDougall

Manure-N availability must be known in order to design application practices that maximize the nutrient value of the manure while minimizing adverse environmental impacts. This study determined the effect of time and rate of liquid manure application on silage corn yield and N utilization, and residual soil nitrate at harvest, in south coastal British Columbia. Liquid dairy or liquid hog manure was applied at target rates of 0, 175, 350 or 525 kg N ha−1, with or without addition of 100 kg N ha−1 as inorganic fertilizer, at two sites in each of 2 yr. Time of liquid-dairy-manure application was also tested at two sites in each of 2 yr with N-application treatments of: 600 kg N ha−1 as manure applied in spring; 600 kg N ha−1 as manure applied in fall; 300 kg N ha−1 as manure applied in each of spring and fall; 200 kg N ha−1 applied as inorganic fertilizer in spring; 300 kg N ha−1 as manure plus 100 kg N ha−1 as inorganic fertilizer applied in spring; and a control that received no applied N. Fall-applied manure did not increase corn yield or N uptake in the following growing season. At all sites, maximum yield was attained using manure only. Selection of proper spring application rates for manure and inorganic fertilizer were found to be equally important in minimizing residual soil nitrate at harvest. Apparent recovery of applied N in the crop ranged from 0 to 33% for manure and from 18 to 93% for inorganic fertilizer. Key words: N recovery, manure management


1965 ◽  
Vol 2 (5) ◽  
pp. 442-484 ◽  
Author(s):  
Donald Carlisle ◽  
Takeo Susuki

The highly deformed section at Open Bay is one of the few good exposures of a thick sedimentary unit within the prebatholithic rocks along coastal British Columbia. It provides new structural information relating to emplacement of a part of the Coast Range batholith and it contains an important Upper Triassic fauna unusually well represented. Structural and paleontological analyses are mutually supporting and are purposely combined in one paper.Thirteen ammonite genera from 14 localities clearly substantiate McLearn's tentative assignment to the Tropites subbullatus zone (Upper Karnian) and suggest a restriction to the T. dilleri subzone as defined in northern California.Contrary to an earlier view, the beds are lithologically similar across the whole bay except for variations in the intensity of deformation and thermal alteration. Their contact with slightly older relatively undeformed flows is apparently a zone of dislocation. Stratigraphic thicknesses cannot be measured with confidence, and subdivision into "Marble Bay Formation" and "Open Bay Group" cannot be accepted. Open Bay Formation is redefined to include all the folded marble and interbedded pillow lava at Open Bay. Lithologic and biostratigraphic correlation is suggested with the lower middle part of the Quatsino Formation on Iron River, 24 miles to the southwest. Basalt flows and pillowed volcanics west of Open Bay are correlated with the Texada Formation within the Karmutsen Group.The predominant folding is shown to precede, accompany, and follow intrusion of numerous andesitic pods and to precede emplacement of quartz diorite of the batholith. Structural asymmetry is shown to have originated through gentle cross-folding and emplacement of minor intrusives during deformation.


1936 ◽  
Vol 2 (5) ◽  
pp. 473-475
Author(s):  
W. A. Riddell

Determinations of the Ca, Mg, Na, K, P and Cl content were made and the ratios of calcium, magnesium and phosphorus oxides suggest the presence of calcium and magnesium metaphosphates in the ash of the flesh, calcium metaphosphate in that from the skin and tribasic calcium orthophosphate in that from the bone.


1986 ◽  
Vol 43 (8) ◽  
pp. 1504-1514 ◽  
Author(s):  
F. Joan Hardy ◽  
Ken S. Shortreed ◽  
John G. Stockner

Inorganic nitrogen and phosphorus were applied weekly during the growing season from 1980 to 1982 and twice weekly in 1983 to Hobiton Lake, a warm monomictic coastal lake in British Columbia. The lake was not fertilized in 1984. Average numbers of bacteria during the growing season decreased from a high of 1.53 × 106∙mL−1 in the fertilized condition to 0.84 × 106∙mL−1 in the unfertilized condition. Chlorophyll a concentrations decreased from a maximum seasonal average of 2.69 μg∙L−1 (1981) to 1.30 μg∙L−1 (1984), and algal numbers decreased from 5.83 × 104∙mL−1 (1983) to 2.29 × 104∙mL−1 (1984). Although the numbers of phytoplankton in each size fraction (picoplankton, nanoplankton, or microplankton) decreased in the unfertilized condition, the greatest change was an almost fourfold decrease in picoplankton, which consisted of 90% cyanobacteria (primarily Synechococcus spp.). Abundance of the large diatoms Rhizosolenia spp. and Melosira spp. increased in 1984, resulting in an increase in average seasonal algal volume. Average densities of medium (0.15–0.84 mm) and large (0.85–1.5 mm) zooplankton were greatest in 1982, while rotifers and small zooplankton (0.10–0.14 mm) were most dense in 1984 following nutrient reduction. The lake had relatively high concentrations of planktivorous juvenile sockeye salmon (Oncorhynchus nerka) that appeared to minimize any direct effect of nutrient additions on zooplankton densities.


2016 ◽  
Vol 5 (1) ◽  
pp. 87
Author(s):  
Celine Plante ◽  
Audrey Smargiassi ◽  
Francine Hubert ◽  
Sophie Goudreau

The common ragweed (<em>Ambrosia artemisiifolia</em>) is widespread in southwestern areas of Quebec, Canada. It is known to release large quantities of pollen from July through September, triggering allergic reactions such as rhinitis and generating significant costs for public health. The objective of this study was to implement and evaluate a communication intervention aimed at decreasing ragweed pollen. Selected lands with potential ragweed presence were visited twice, before and after the intervention, on three seasons in the East of the Montreal Island, Quebec. At the first visit done in 2010, 2011, and 2012, ragweed plots were located and measured; at the second visit in 2012, the measures were redone. Various numbers of communications were sent to owners of ragweed-infested lands that included explanations of health impacts of ragweed pollen and the importance of mowing. Mixed logistic regressions were used to test the effect of the number of communications on the mow. In the group that received four notices, a statistically significant three-fold increase in the proportion of land owners that had cut ragweed plots (OR = 3.20; 95 %CI: 1.16-8.84) was noted, compared to the group that received only one notice. For owners of vacant lands, the effect was somewhat more pronounced (OR = 3.82; 95%CI: 1.23-11.67). Nonetheless, the change from one to three communications showed no increase of mowing. In conclusion, the results of the present study suggest that communications and reminders of the importance of ragweed cut to landowners could be an effective measure to limit ragweed pollen.


2016 ◽  
Vol 46 (1) ◽  
pp. 50-74
Author(s):  
Jason Redden

This paper addresses the academic conversation on Protestant missions to the Indigenous peoples of coastal British Columbia during the second half of the nineteenth century through a consideration of the role of revivalist piety in the conversion of some of the better known Indigenous Methodist evangelists identified in the scholarly literature. The paper introduces the work of existing scholars critically illuminating the reasons (religious convergence and/or the want of symbolic and material resources) typically given for Indigenous, namely, Ts’msyen, conversion. It also introduces Methodist revivalist piety and its instantiation in British Columbia. And, finally, it offers a critical exploration of revivalist piety and its role in conversion as set within a broader theoretical inquiry into the academic study of ritual and religion.


1959 ◽  
Vol 16 (6) ◽  
pp. 903-922 ◽  
Author(s):  
S. U. Qadri

Coastal cutthroat trout, S. c. clarkii Richardson, occupy most lakes and streams of coastal British Columbia, including the adjacent islands. Yellowstone cutthroat, S. c. lewisi (Girard), occupy southeastern British Columbia; their range is separated from that of the coastal subspecies by a zone lacking cutthroat trout. A map showing all natural distribution records in the province is presented. From 60 to 146 specimens were examined for distinguishing characters. Spots below the lateral line are more numerous towards the anterior end in S. c. clarkii, but more numerous towards the posterior end in S. c. lewisi. A plot of spot number in selected areas of the body provides almost complete separation of individuals of the two subspecies. Significant differences also occur in certain scale counts and in body and peduncle depth, although these characters overlap considerably between the subspecies. No difference was found in vertebral count.


2021 ◽  
Vol 51 (2) ◽  
pp. 175-183
Author(s):  
Mitsuharu Yagi

To study the effects of a typhoon on a temperate, coastal bay community, the species composition, catch amount, and diversity of epipelagic fish assemblages were investigated. Fish samples were taken from catches of a purse seine fishery in Tachibana Bay, Japan between May and July 2011, covering before and after the passage of a typhoon in the area. Although major changes in total catch amount were not observed before and after the passage of the typhoon, the abundance of the Japanese anchovy, Engraulis japonicus Temminck et Schlegel, 1846, markedly decreased and bycatch of species increased, accompanied by increasing levels of diversity of the fish assemblage. Multivariate analysis showed that community differences before and after the passage were quantitative rather than qualitative. Comparisons in total length frequencies between the two periods indicated that specimens of the species compared were bigger in size for Trachurus japonicus (Temminck et Schlegel, 1844) and smaller for E. japonicus in the “after” period. These results suggest that the passage of the typhoon triggered not only interspecific faunal change but also intraspecific recruitment shifts in and around the bay.


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