Diatoms as indicators of lake trophic status

Relationships between surface sediment diatom assemblages and lake trophic status were studied in 50 Canadian Precambrian Shield lakes in the Muskoka-Haliburton and southern Ontario regions. The purpose of this study was to develop mathematical regression models to infer lake trophic status from diatom assemblage data. To achieve this goal, however, additional investigations dealing with the evaluation of lake trophic status and the autecological features of key diatom species were carried out. Because a unifying index and classification for lake trophic status was not available, a new multiple index was developed in this study, by the computation of the physical, chemical and biological data from 85 south Ontario lakes. By using the new trophic parameter, the lake trophic level (TL) was determined: TL = 1.37 In[1 +(TP x Chl-a / SD)], where, TP=total phosphorus, Chl-a=chlorophyll-a and SD=Secchi depth. The boundaries between 7 lake trophic categories (Ultra-oligotrophic lakes: 0-0.24; Oligotrophic lakes: 0.241-1.8; Oligomesotrophic lakes: 1.813.0; Mesotrophic lakes: 3.01-4.20; Mesoeutrophic lakes: 4.21-5.4; Eutrophic lakes: 5.41-10 and Hyper-eutrophic lakes: above 10) were established. The new trophic parameter was more convenient for management of water quality, communication to the public and comparison with other lake trophic status indices than many of the previously published indices because the TL index attempts to Increase understanding of the characteristics of lakes and their comprehensive trophic states. It is more reasonable and clear for a unifying determination of true trophic states of lakes. Diatom specIes autecology analysis was central to this thesis. However, the autecological relationship of diatom species and lake trophic status had not previously been well documented. Based on the investigation of the diatom composition and variety of species abundance in 30 study lakes, the distribution optima of diatom species were determined. These determinations were based on a quantitative method called "weighted average" (Charles 1985). On this basis, the diatom species were classified into five trophic categories (oligotrophic, oligomesotrophic, mesotrophic, mesoeutrophic and eutrophic species groups). The resulting diatom trophic status autecological features were used in the regressIon analysis between diatom assemblages and lake trophic status. When the TL trophic level values of the 30 lakes were regressed against their fi ve corresponding diatom trophic groups, the two mathematical equations for expressing the assumed linear relationship between the diatom assemblages composition were determined by (1) uSIng a single regression technique: Trophic level of lake (TL) = 2.643 - 7.575 log (Index D) (r = 0.88 r2 = 0.77 P = 0.0001; n = 30) Where, Index D = (0% + OM% + M%)/(E% + ME% + M%); 4 (2) uSIng a' multiple regressIon technique: TL=4.285-0.076 0%- 0.055 OM% - 0.026 M% + 0.033 ME% + 0.065 E% (r=0.89, r2=0.792, P=O.OOOl, n=30) There was a significant correlation between measured and diatom inferred trophic levels both by single and multiple regressIon methods (P < 0.0001, n=20), when both models were applied to another 20 test lakes. Their correlation coefficients (r2 ) were also statistically significant (r2 >0.68, n=20). As such, the two transfer function models between diatoms and lake trophic status were validated. The two models obtained as noted above were developed using one group of lakes and then tested using an entirely different group of lakes. This study indicated that diatom assemblages are sensitive to lake trophic status. As indicators of lake trophic status, diatoms are especially useful in situations where no local trophic information is available and in studies of the paleotrophic history of lakes. Diatom autecological information was used to develop a theory assessing water quality and lake trophic status.

Understanding space, place and leisure of women over 85 living in the community

There is an increase in the number of older adults 85 and over, who are choosing to live alone within the community. Moreover, older adults who live alone are reportedly spending an extensive amount of time alone within the home environment. In an effort to provide additional support and resources to older adults living in the community, a compliment of services are being offered through public and private organizations. These in-home supports focus on the instrumental or functional tasks of daily living, such as personal and rehabilitative care, nourishment, maintenance and upkeep of the home, as well as volunteer social visitation. However leisure resources and programs are not included among these services. Consequently, this creates a gap in leisure provision among this segment of the population. Throughout the life course, an individual's identity, role and purpose are developed and sustained through instrumental work roles in the formal and informal sector, as well as through personally meaningful leisure pastimes and experiences. Although roles shift post retirement, participation in instrumental and expressive activities can provide opportunities through which older adults are able to fulfill their need for agency (individuality and autonomy) and affiliation (social relatedness). Therefore barriers that inhibit instrumental or leisure experiences can negatively impact older adults' quality of life. This study explored the leisure lifestyles of four older adults, all of whom were over 85, lived alone within the community and were oriented to person, time and place. It became apparent that participants ordered their lives around a routine that consisted of instrumental, expressive and socially integrated tasks and activities. Moreover participants purposely chose to remain at home because their home environment facilitated freedom, choice and independence. As a result all four participants viewed their independence within the home as a critical determinant to their overall quality of life. Challenges associated with the home environment, participants' personal capacities and relationships were negotiated on a daily basis. Failure to positively adapt to these challenges inhibited meaningful engagement and personal fulfillment. Traditionally, leisure service delivery has been offered within institutions and through various community based venues. As a result leisure provision has been focused on the needs of the frail elderly who reside in institutions or the well elderly who are able to access leisure amenities within the community. However the growing number of older adults electing to live alone is on the rise. As individuals age the home becomes the preferred context for leisure experiences. If older adults are choosing to live alone, then both their instrumental and leisure needs must be addressed. As a result, it is imperative that leisure professionals extend the scope of service delivery to include home centered older adults.

Morrey's Farmers and Business Directory, Containing the Following Valuable Information: The Name, with the Post Office Address, Lot and Concession, of each Farmer; also whether a Freeholder or a Tenant (1884/85)

The Union Publishing Co.'s farmers' and business directory for the counties of Haldimand, Lincoln, Welland & Wentworth.

HG 186.80-186.85 Thin section

A coarse grained sample with clay rich domains. Grains range from small to medium and are sub-angular. Rotation structures can be seen around sub-rounded clasts. Lineations can be seen throughout the image, mainly short distance lineations. Small comet structures can also be seen throughout the images.

HG 206.85-206.95 Thin Section

Coarse grained sample with sub-angular to sub-rounded clasts. Clasts range from small to medium sized. Major grain crushing seen throughout the sample. Grain stacking and lineations are also present. A dark organic rich domain can be seen within the sample.

HG 230.75-230.85 Thin Section

Coarse grained sediment with fine grained domains, clay material, rotation structures and lineations. Clasts range from sub-angular to sub-rounded. Mainly brown sediment with darker patches of brown throughout. Major amounts of grain crushing can be seen in the coarse grained material.

HG 303.85-303.95

This is a dark grey, coarse grained sediment with inclusions of fine grained sand. Lineations and grains stacking are the most common features seen, along with grain crushing (mainly edge-to-edge). A few minor rotation structures can also be observed with comet structures.

HG 380.85-380.95

Brown sediment with alternating layers of dark and light sediment. Clasts range from small to large, and are sub-angular. Lineations are abundant in this sample, trending mainly in one direction. Some rotation structures are present.

384.85-385.0 DE # 11

Mainly coarse grained with a separate fine grained clay domain occurring throughout the sample. The coarse grained domain contains clasts that range from small to medium in size. The clast shape ranges from angular to sub-angular. Grain crushing is abundant in this sample, along with lineations, and minor amounts of rotation.

HG 388.75-388.85

Dark brown sample with clasts that range from small to large. The clast shape ranges from angular to sub-rounded. Grain crushing is present in this sample along with some lineations. Faint water escape structures can also be seen.

HG 393.60-393.85

Brown sediment with clasts that range from small to large. The clast shape ranges from angular to sub-rounded. Lineations and water escape structures are present. Grain crushing and minor amounts of rotation are also present.

HG 406.85-406.95

Brown sediment with organic matter and clasts ranging from small to large. The clast shape ranges from sub-angular to sub-rounded. Lineations and grain stacking are the most abundant in this sample. Minor amounts of grain crushing can also be seen.

HG 3.75-3.85

Dark brown sediment with clasts ranging from small to large. The clasts range from angular to sub-rounded in shape. The sample mainly contains edge-to-edge grain crushing and rotation structures. Many grains are fractured and a few necking structures can also be seen.

HG 34.70-34.85

Dark brown sediment with clasts that range from small to medium in size. The clasts were sub-angular to sub-rounded in shape. Lineations were abundant throughout the sample. It also contains some clay material and a few rotation structures.