• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 26
  • 6
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 55
  • 7
  • 7
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 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

Aspects of the ecology, population structure, and reproductive strategy of Arizona cypress (Cupressus arizonica Greene) in southeastern Arizona

Parker, Albert John. January 1977 (has links)
Thesis--Wisconsin. / Includes bibliographical references (leaves 99-102).
2

Impact of exotic Ponderosa pine (Pinus ponderosa Doug. ex Laws. ) plantations on water resources in northwestern Patagonia, Argentina /

Licata, Julian A. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 136-151). Also available on the World Wide Web.
3

Screening for resistance to Seiridium canker in the Cupressaceae and vegetative propagation of cypresses

Spanos, Konstantinos A. January 1995 (has links)
Artificial inoculations in the Cupressaceae proved that <I>Seiridium cardinale</I> was more virulent than <I>S.cupressi</I> and <I>S.unicorne. Cupressus macrocarpa</I> was found to be highly susceptible to <I>Seiridium</I> canker, <I>C.sempervirens</I> very susceptible, while <I>C.torulosa</I> and <I>C.arizonica</I> were moderately susceptible. <I>Chamaecyparis lawsoniana</I> was highly resistant to <I>S.cardinale</I>, but very susceptible to <I>S.unicorne</I> and moderately susceptible to <I>S.cupressi</I>. Intraspecific variation in susceptibility to <I>S.cardinale</I> was found in <I>C.sempervirens. S.cupressi</I> was more pathogenic than <I>S.unicorne</I> on <I>C.macrocarpa, C.arizonica</I> and <I>C.torulosa</I>, whereas it was less pathogenic on <I>C.sempervirens</I>. Mature bark proved to be more resistant to <I>Seiridium</I> canker than young bark. Low variability in pathogenicity of <I>S.cardinale</I> was found, with only one isolate out of eight proving to be a weaker pathogen. Histological examination of bark of cypress seedlings following infection with <I>S.cardinale</I> revealed the formation of strong necrophylactic periderm as an important resistance mechanism against <I>Seiridium</I> attack, and was particularly marked in <I>C.lawsoniana</I>. Strong necrophylactic periderms were detected in resistant and tolerant clones of <I>C.sempervirens</I>, whereas weak or a series of easily re-invaded ones were found in susceptible clones. Variations in pathogenicity of <I>Seiridium</I> in <I>in vitro</I> inoculations of micropropagated cypress shoots paralleled results found in the glasshouse. Wounding of micropropagated shoots significantly increased the size of lesions caused by all three <I>Seiridium</I> spp. In axenic conditions, hyphae of <I>Seiridium</I> spp. penetrated host tissues through stomatal apertures or directly through the cuticle. Under these conditions, infected tissues of <I>C.lawsoniana</I> formed ligno-suberized barriers as a result of fungal invasion, whereas those of <I>C.sempervirens</I> did not.
4

Cypress Bark Beetles

Schalau, Jeff 06 1900 (has links)
2 pp. / Other Forest Health Publications / Cypress bark beetles are native insects that often impact ornamental Arizona cypress and Leyland cypress trees. Healthy, vigorous cypress trees can usually withstand substantial beetle pressure. However, significant mortality of host tree species often occurs during periods of extended drought. Tree vigor can easily be maintained through deep, infrequent irrigation during drought periods.
5

Cypress Bark Beetles

Schalau, Jeff 12 1900 (has links)
Revised; Originally Published: 2003 / 2 pp.
6

A Hydrologic and Hydraulic Assessment of Cypress Creek for the Identification of the Potential Habitat for the Bald Cypress and Water Tupelo

Gracer, Tara 01 May 2020 (has links)
Cypress Creek is an under researched sub-watershed of the larger Cache River system located in Southern Illinois and is managed by the Cypress Creek National Wildlife Refuge (CCNWR). In 1996, the Cypress Creek Watershed and its encompassing wetlands were listed under the United Nations Education, Scientific, and Cultural Organization (UNESCO) and Ramsar as a “Wetland of International Importance”. These wetland habitats house unique aquatic woody species, such as the Bald Cypress and Water Tupelo, and have diminished in size due to agricultural priorities and changes in hydrology (Demissie et al. 1990; Illinois Department of Natural Resources 1997). Heitmeyer and Mangan (2012) conducted by the U.S. Fish and Wildlife Service (USFWS), assessed the Cypress Creek Watershed using historical references of pre-settlement topography and geomorphology and present-day soils to determine habitat potential. These variables alone do not address the needs of the aquatic woody species who require flood inundation to survive. This hydrologic and hydraulic assessment examines the present-day hydrologic conditions within the boundary limits of CCNWR by collecting channel geometry and stream discharges, building flow frequencies, and constructing a hydraulic model of Cypress Creek to simulate water surface elevations (WSELs) for the bankfull, 2-year, 5-year, 10-year, 20-year, and 25-year exceedance probabilities. Flood inundations were generated from simulated WSELs and local topography. The calculated potential habitat for Bald Cypress and Water Tupelo is 289 hectares and is located in the northwest part of the study area, south of Cypress Creek Road and above Hickory Bottoms Bridge on CCNWR land. Potential habitat overlap found between Heitmeyer and Mangan (2012) and this assessment is roughly 19 hectares.
7

A comparison of cypress ecosystems in the landscape of Florida

Brown, Sandra Lazowska, January 1978 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. REPL* Includes bibliographical references (leaves 555-569).
8

Effects Of Patch Size And Matrix Type On Bird Assemblages Within Central Florida Cypress Domes

Noran, Julia 01 January 2006 (has links)
The numerous studies on the effects of patch size on bird assemblages have produced varied results. I studied the effects of patch size and surrounding matrix on bird assemblages within central Florida cypress domes. My null hypothesis was that bird assemblages within cypress domes are unaffected by dome size or development in the matrix around the dome. My alternative hypothesis was that differences in bird assemblages are correlated with size and the degree of development within the matrix. I classified a pool of over a thousand domes according to three size categories and four matrix types. Three representatives for each combination of size and matrix were spot mapped for birds from May through August 2005. I examined the relationship of species richness and bird guilds to patch size and surrounding matrix. I also measured a series of potential covariates for each dome to account for variation among the three size-matrix representatives for each combination. Richness and abundance counts were divided by the number of listening points to standardize the data by effort. I found that the standardized species richness of bird assemblages significantly increased with the patch size of cypress domes; however, matrix and the interaction effect of size and matrix on overall standardized species richness were not significant. Significant covariates included percent of the buffer undeveloped, percent herbaceous cover, and the number of listening points per unit area. A linear regression tested for significant effects of log area and matrix on standardized species richness. Matrix was not significant, but log area did have a significant effect on standardized species richness. The MANOVA tests for guild richness data indicated no significant effects of dome size, matrix, or their interaction effect on diet, foraging, or location guilds. There were no significant main or interaction effects on any individual guilds in the ANOVA output. Individual backward linear regressions done on each guild indicated that matrix did not have significant effects on any guild, but log area had significant effects on ground foragers, lower-canopy foragers, omnivores, herbivores, and edge species. I then investigated the effects of size and matrix on standardized guild abundance. Dome size and matrix significantly effected diet guild abundance, but the size-matrix interaction did not. Dome size significantly affected insectivores, omnivores, and carnivores. Matrix had a significant effect on omnivores, herbivores, and carnivores. The size and matrix interaction had a significant effect on carnivores. Dome size and matrix significantly affected foraging guild abundance, but the size-matrix interaction did not. Dome size significantly affected ground, lower- and upper-canopy foragers. Matrix had a significant effect on ground, water, and upper-canopy foragers. The size and matrix interaction was not significant for any foraging guild. Dome size and matrix significantly effected location guild abundance, but the size-matrix interaction did not. Dome size significantly affected edge and interior species. Matrix had a significant effect on edge and interior species. The size and matrix interaction was not significant for any location guild. The relationship between species richness and habitat area is well-documented, and the results of this study were consistent with the expectation of higher species richness in larger areas. If maintaining high species richness is the sole goal of conservationists, then large habitat fragments would be preferable regardless of surrounding matrix. Nevertheless, species richness alone is not informative of the potential effects of patch size and matrix on the composition of an avian assemblage. Guild analysis gives insight into community structure and should be considered in addition to simple measures of species richness. Patch size and matrix type significantly affected a number of guilds, and several factors could contribute to the observed differences in guilds across patch size categories and matrix types. Different habitats are available to birds in domes of each size class and matrix type. The potential for diverse foraging opportunities increases as domes increase in size and change in relation to their surrounding matrix. A more detailed analysis is needed to determine how differences in vegetation of domes and surrounding matrix affect guilds, members of which may use habitats both within domes and the matrix. Cypress domes in the central Florida area face severe alteration or destruction due to rapid development. Long-term research that focuses on domes before and after development is needed to understand how changes in the matrix or size of the domes affect all resident flora and fauna. A variety of taxa and biogeochemical processes should be researched. Domes are naturally highly variable in size, shape, and structure, and development changes all of these characteristics. Conservation biologists and managers urgently need to determine how development affects cypress domes and what can be done to maintain their characteristic biodiversity.
9

Analysis and comparison of essential oil components extracted from the heartwoods of Leyland cypress, Alaska yellow cedar, and Monterey cypress /

Liu, Xinfeng. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 42-46). Also available on the World Wide Web.
10

Element Mobility In Bald Cypress Xylem

Galicki, Stanley J., Davidson, Gregg R., Threlkeld, Stephen T. 06 1900 (has links)
Trace element mobility in bald cypress (Taxodium distichum) was investigated for a suite of elements using cores from century-old trees from a wetland in Humphreys County, Mississippi. Element mobility was determined by comparing the dendrochemistry of decadal increments over the life span of a tree, and by comparing increments of the same age collected from the same tree during two different seasons. Variability within growth increments at the time of sampling was evaluated by comparing cores from the same tree collected at three points around the bole. Of 42 elements analyzed, eight were found above detection limits (As, Ca, K, Mg, Mn, Na, P, Zn). Clear evidence of translocation of P and Mn to the sapwood and K, Mg, and Na to the heartwood was observed. Ca and Zn were found with higher average concentrations in the sapwood, though evidence of translocation to the sapwood was equivocal. Arsenic did not vary significantly through any individual core. Variation in concentration was not found to be significant for any element with respect to year of sampling, season, location in the wetland, or position around the bole. With the exception of As, variation was significant with respect to increment age (decade) and location within the heartwood or sapwood.

Page generated in 0.0614 seconds