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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Floristic Study of the Cal Poly Swanton Pacific Ranch and a New Combination in Sanicula crassicaulis (Apiaceae), Sanicula crassicaulis var. Nudicaulis

Kenny, Reed J 01 June 2020 (has links) (PDF)
Globally we are experiencing a biodiversity crisis and potentially a sixth mass extinction event. Plant specimens are one of the best, most concrete records of biodiversity that we can create. Despite this, the rate of plant collecting has declined steeply since World War II. Now more than ever, plant collections are vital, both for the purpose of quantifying the plant biodiversity in an area and for discovering previously unrecognized diversity. In Chapter 1, we conducted a floristic survey of the Cal Poly Swanton Pacific Ranch. The Swanton Pacific Ranch (SPR) is located north of the small town of Davenport California, in Santa Cruz county. SPR is 3,200 acres and contains areas of salt marsh, coastal bluff, coastal prairie, riparian forest, redwood forest, mixed conifer forest and chaparral in approximate ascending order of elevation. The property extends over an elevational gradient from 0 m to 420 m (1400 ft). We documented 634 taxa at SPR. In total, 974 specimens were collected during this project, 405 specimens in 2017 and 569 in 2019. We reviewed 211 historic specimens. We vouchered 546 taxa between 2017 and 2019 and observed but did not collect 6 taxa. 53 taxa are represented from historic collections and were not relocated. There are 30 taxa listed as historically present from personal observations of the authors but without vouchers. Though these do not have the same value as a physical specimen, we believe that all information is valuable and have included them with a clear indication of the source of the record. There were 465 native and 169 non-native taxa documented in the study area. There were 93 families represented, with Asteraceae, Poaceae and Fabaceae be ing the top three most speciose respectively. There were 83 taxa noted as locally rare following Neubauer, of these 16 taxa have a California Native Plant Society (CNPS) rare plant rank. We vouchered one new taxon for Santa Cruz County, Senecio aphanactis, which has a CNPS rare plant rank of 2B.2 In Chapter 2, we describe a new combination in the Sanicula crassicaulis species complex. During the project detailed in Chapter 1, we observed and collected several specimens that keyed to Sanicula crassicaulis Poepp. ex. D.C. but were notably distinct from other S. crassicaulis that we collected in the area. On further investigation, we found that these plants match the type specimen of S. nudicaulis Hook & Arn., described in 1839 and later synonymized with S. crassicaulis. This taxon is distinguished primarily by its long, sinuate marginal leaf trichomes, in contrast to the short, straight marginal trichomes of S. crassicaulis. Additionally, the length of the most proximal prickles on the schizocarps is about the same as the length of the most distal rather than the distal prickles being much longer as in S. crassicaulis and the angle of attachment of the prickles is more or less perpendicular as opposed to acute in S. crassicaulis. The known range of this taxon is between the San Francisco Bay Area and Santa Barbara County, generally near the coast. Here we recognize this taxon as a variety in S. crassicaulis, Sanicula crassicaulis var. nudicaulis. We provide a diagnosis, a map of the known range of the taxon and a key to the varieties of S. crassicaulis. Overall this project has significantly increased or knowledge and documentation of the flora of both SPR and Santa Cruz county. In addition to the immediate benefits of this study (a complete species list for SPR, the discovery of a new taxon, and the mapping of all rare species at SPR) we have also contributed almost 1,000 physical specimens to the Cal Poly Hoover herbarium which may be used in future taxonomic and ecological studies.
2

Development of Watershed Action Plans for the Mill Creek and Yellow Creek Watersheds

Korenic, Robert J. January 1999 (has links)
No description available.
3

Development of an internet watershed educational tool (InterWET) for the Spring Creek watershed of Central Pennsylvania

Parson, Shane Cannon. January 1900 (has links)
Thesis (Ph. D.)--Pennsylvania State University, 1999. / Diskette not included. --UMI note. Includes bibliographical references (leaves 88-92).
4

Population densities and food selection of small rodents in Arizona ponderosa pine forests

Goodwin, John Gravatt, 1949- January 1975 (has links)
No description available.
5

Analysis of Riparian Forest and Floodplain Quality in the Yellow Creek Watershed: Using the Qualitative Habitat Evaluation Index

Williamson, Robert A. January 1999 (has links)
No description available.
6

Physiological Ecology, Population Genetic Responses and Assemblage Stability of Fishes in Two Southwestern Intermittent Stream Systems

Rutledge, Charles Jerry, 1941- 12 1900 (has links)
Six sites within the Denton and Hickory Creek watersheds were sampled over three years to assess the impact of seasonal intermittent stream conditions on the ichthyofauna. An integrated approach using field and laboratory techniques was employed to evaluate the responses of the fishes.
7

Runoff simulation in the Canagagigue Creek watershed using the MIKE SHE model

Oogathoo, Shalini. January 2006 (has links)
No description available.
8

Runoff simulation in the Canagagigue Creek watershed using the MIKE SHE model

Oogathoo, Shalini. January 2006 (has links)
The Canagagigue Creek watershed, located in the Grand River Basin, is one of the fastest developing areas in Ontario. The watershed hydrology has changed considerably due to the increased anthropogenic activities, producing frequent floods and droughts as well as water quality problems. MIKE SHE, a watershed-scale model, was used to simulate surface runoff from the Canagagigue Creek watershed. Various management scenarios affecting the surface hydrology were also evaluated. The model was calibrated for four years (1994-95 to 1997-98) and validated for another four years (1990-91 to 19931-94). For the calibration period, the correlation between the observed and simulated daily runoff was satisfactory, as shown by the coefficient of determination value of 0.59. The coefficient of determination was 0.44 for the validation period. The Nash-Sutcliffe coefficients obtained were 59% and 40% for the calibration and validation period, respectively. Use of daily input data together with a simplistic snowmelt routine, was found to affect model performance during the winter/spring period. Henceforth, model performance can be greatly improved by adopting a more comprehensive method for simulating snowmelt and incorporating the frozen soil conditions. Overall, the model was able to simulate surface runoff reasonably well on annual, seasonal, monthly, and daily intervals, representing all the hydrological components adequately. / With the various management scenarios simulated, it was found that the deforestation scenario considerably increased the total flow (11%). On the other hand, the high runoff peaks were decreased and low flows were increased considerably in the application of the tile drainage scenario. It was also observed that surface flow increased in wet years and decreased in normal and dry years in the climate change scenario. Though impacts of certain scenarios were almost negligible, their effects were significant when associated with the percentage area under transformation. Hence, it was concluded that the model can be used to simulate various management scenarios to solve hydrologic problems in the Southern Ontario climatic condition.
9

Comparison of two hydrological models on a Virginia Piedmont watershed /

Fu, Youtong, January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 168-174). Also available via the Internet.
10

Evaluation of the soil land inference model in Big Elk Creek Watershed, Chester County, Pennsylvania

Varaghur, Ranjani. Day, Rick L., January 2008 (has links)
Thesis (M.S.)--Pennsylvania State University, 2008. / Mode of access: World Wide Web. Thesis advisor: Rick Lane Day.

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