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- Creator:
- Jeffrey P. Reiner
- Description:
- Suspended sediment was investigated above and below beaver ponds in the Beaver Creek drainage in the south central mountains of Idaho near Idaho City from March 1979 through September 1979. The study was to identify the potential for beaver ponds as settling basins for suspended sediment in wildland watersheds. Two sampling stations were established above and below a beaver colony. The parameters measured included suspended sediment, stream discharge, and water temperature. Also, the beaver pond volumes and surface areas and beaver dam lengths and heights were measured. The data were collected weekly from March through September, except during May and June when sampling was more frequent to bracket the peak flow period. The data demonstrated that suspended sediment was deposited in the beaver ponds. The proportion of suspended sediment deposited in the beaver ponds averaged about 38 percent on the rising limb, 10 percent during the peak flow period, and 65 percent on the falling limb. The suspended sediment ratio was negatively correlated with stream discharge and positively correlated with water temperature. The relationship between the suspended sediment ratio and the stream discharge and water temperature was significant at the 0.05 level. The quantity of suspended sediment deposited in the beaver ponds during the study period was 78.2 tons, which was approximately 25 percent of the suspended sediment load transported through the above sampling station.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Environmental Science & Management
- Creator:
- J. Lincoln Freese
- Description:
- The abundance, seasonal distribution, holding habitat and behavior of adult summer steelhead were studied during the summers of 1979-1981 in the Trinity River system, California. The North Fork Trinity River and New River were the only streams in the drainage harboring significant numbers of steelhead during the summer months. Estimated combined run size for both streams ranged from a maximum of 776 fish in 1980 to a minimum of 455 fish in 1981. Summer steelhead began entering the tributaries in early June; entry peaked during mid-July. Steelhead numbers and distribution had substantially stabilized by early August. Summer steelhead were tagged in a single holding pool in the North Fork Trinity River during September 1981. Subsequent surveys revealed that they remained in that pool until the first storm fronts had passed through the area in early October, at which time small groups of fish rapidly migrated upstream. However, some tagged fish were still present at the tagging site in early November. High stream discharge precluded further survey work after that time. Holding pools do not appear to be a limiting factor for adult summer steelhead in either tributary. During the study period, the percentage of pools harboring one or more adult summer steelhead ranged from a minimum of 14 percent to a maximum of 36 percent in the North Fork; corresponding values for the New River were 27 percent and 31 percent. Twenty-seven pools in the New River were surveyed periodically during the summer of 1980. Factor analysis suggested a relationship between steelhead numbers in pools and available cover and shade, but failed to show a relationship between steelhead numbers, pool dimensions, upstream gradient, downstream gradient or distance to first downstream pool. Although no statistical analysis of steelhead numbers and other pool variables was performed for the North Fork Trinity River, observations indicate a high correlation between steelhead numbers and pool dimensions in that stream. Gold-dredging activity was heavy in the New River watershed, and appeared to have had an effect upon steelhead distribution among holding pools in that stream. Heavy poaching activity is a significant threat to the continued survival of the summer steelhead run in the New River drainage. U.S. Forest Service barrier modification efforts in the North Fork Trinity River appeared to have had an effect upon summer steelhead distribution. Steelhead were observed in greater numbers in upstream areas, and were concentrated in a fewer numbers of pools, after barriers were modified. Analysis of scales taken from North Fork Trinity River summer steelhead revealed that 95 percent of returnees smolted at age 2, 44 percent of returnees made their initial upstream migration as "halfpounders", and 42 percent of returnees were repeat spawners.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Fisheries
- Creator:
- Jones, Maureen Gertrude
- Description:
- In most temperate coniferous forests, the vast majority of vascular plant species richness can be found in the understory layer. While the large-scale conversion of forests to plantations has made it increasingly important to understand how understory flora responds to timber harvesting, there is a surprising paucity of data concerning this topic. Ideally, long-term studies using permanent plots would be used to directly assess post-logging patterns of recovery, both for whole floras and for individual species of conservation interest. Unfortunately, these studies are lacking, and alternative approaches are critical. I used a 420 year forest chronosequence to assess the relationship between stand age, overstory cover and vascular plant understory richness and composition in one watershed in the Siskiyou Mountains of Oregon. The chronosequence consisted of six young managed (age 7-44) and nine older unmanaged (age 90-427) stands. All stands were similar in underlying geology, slope, elevation, and aspect. I found a non-linear relationship between stand age and richness, in which richness showed a steady decline as young stands entered canopy closure, then increased as stands gained older forest attributes such as light gaps and structural diversity. I also found that percent open canopy was correlated with total percent understory cover, richness, diversity and changes in species composition. In general, young stands were characterized by high shrub and graminoid cover and old stands were characterized by an abundant herb layer. In my study area, a large proportion of young managed stands are currently entering canopy closure, a stage characterized by low vascular plant species richness and abundance. I use my results to discuss the potential effects of past and future forest management on vascular plant understory species.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Biology
- Creator:
- Fischer, Jon K.
- Description:
- Elk habitat use and group size were studied during winter and spring near Grass Lake in Siskiyou County, California, from September 1982 through June 1984. Habitat use was based on visual observations of elk from December 1982 through June 1983 and December 1983 through June 1984, and telemetry-locations of three cow elk equipped with transmitters from February through June of 1984. Based on data from both methods, elk used meadows more (P<0.05) than their availability. Elk use of some habitats changed seasonally. Woodland use declined from winter to spring, concomitant with increased meadow use. However, elk use of mixed conifers and grasslands did not change from winter to spring. Some sighting-based estimates of habitat use by elk were different from telemetry-based estimates. Sighting-based estimates of mixed conifer use were less (P<0.05) than corresponding telemetry-based estimates. Sighting-based estimates of meadow use for Spring and the Year of 1984 were greater (P<0.05) than corresponding telemetry-based estimates. Sighting-based estimates of use for all other habitats were equivalent (P<0.05) to corresponding telemetry-based estimates of use. Elk mean group size was 15.9 (SD=l3.4, range: 1-46). Mean group size was 19.8 (SD=l6.0) during winter and 14.7 (SD=ll.6) during spring. Group size in meadows was significantly greater (P<0.05), and group size in mixed conifers was significantly less (P<0.05) than the mean group size for the study period.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Creator:
- McGrew, Karen C.
- Description:
- Russian Peak, at an elevation of 8200 feet, is situated in the Salmon Mountains, a north-south trending range centrally located within the Klamath Region of northwestern California. The Salmon Mountains are drained by the Scott River on the east and by the Salmon River on the west; both rivers course northwesterly to discharge into the Klamath River. The Klamath Region is a geologically old and structurally complex series of ranges which grade into the Coast Ranges on the west and into the Cascade Mountains on the northeast. Russian Peak is located in Klamath National Forest, within Siskiyou County, approximately eight miles westsouthwest of the town of Callahan. Access to the area is via Forest Service roads and·unimproved roads off of State Highway 3, which runs northward out of Weaverville. Selection of Russian Peak and its environs as a study area was based on several factors: the lack of bryological collections in the area (Personal communication, Norris, 1973); the presence of relict conifer species as described by Sawyer and Thornburgh (1971); and the presence of a diverse, largely circumboreal moss population on the Marble Mountains, located approximately fifteen miles to the northwest (Spjut, 1971). The objective of the following study was to identify bryophyte species within the area and to determine if the findings would lend further support to the concept of a refugium or "central" area, as described by Whittaker(l961), within the Klamath Region. Collections were made from around five lakes, including their headwaters and drainages, during the summers of 1973 and 1974. A total of 786 specimens were collected, representing 152 species. Collections were made at elevations between 5500 feet and 7200 feet in the following drainages: 1) Sugar Lake and Sugar Creek, August, 1973; 2) South Sugar Lake, August, 1974 (with D.H. Norris); 3) Bingham Lake, September, 1974 (with D.H. Norris); 4) Russian Lake, September, 1973; 5) Waterdog Lake, Lower Russian Lake and South Russian Creek, September, 1973. Bryophytes were collected along paths, in drainages, and from around the lakes. Effort was made to include special habitats, such as springs, marshes, serpentine outcrops, exposed granite walls, rock crevices, and areas adjacent to perennial snow patches. Each collection was identified, checked with specimens from the cryptogamic collection at Humboldt State University, and verified by D. H. Norris. Voucher specimens are on deposit at the Humboldt State University Herbarium (HSC). Collection numbers preceded by the prefix "N" are those of D. H. Norris; all others are those of the author.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Biology
- Creator:
- Tennyson, Jo
- Description:
- Handwriting/fine motor difficulties are well documented as serious hindrances to academic learning for kindergarten and elementary school children. Intervention techniques to remediate these problems have been researched by educators and occupational therapists. Effective occupational therapy interventions have been found to include visual motor tasks, kinesthetic and dexterity training and motor planning/strengthening activities. Occupational therapists, mandated by the Individuals with Disabilities Education Act, work with these students in the school setting to enhance handwriting/fine motor skills to meet classroom curriculum demands. Humboldt County teachers have reported a high incidence of students with these deficits in their classrooms yet reported a low frequency of referral to occupational therapists for intervention. Funding and a lack of general knowledge about the role of therapists’ in the school setting appear to be barriers to implementation of therapy services for students. These same teachers indicated a strong interest in continuing education on remediation techniques. An educational module designed for staff development for teachers in Humboldt County on handwriting/fine motor intervention strategies appears to be needed. Curriculum for students is rigorous with many academic topics to cover. Imbedding fine motor remediation techniques into another discipline seems advantageous. Food related activities naturally lend themselves to fine motor involvement. Staff training encouraging vegetable awareness and handwriting skill acquisition is an effective way to impact student learning in two specialty areas. Linking fine motor intervention with nutrition education will be a cost effective, compelling, and creative solution to meet teacher and ultimately student needs in Humboldt County.
- Resource Type:
- Thesis and Presentation
- Campus Tesim:
- Humboldt
- Department:
- Education
- Creator:
- McGourty, Katie R.
- Description:
- Eucyclogobius newberryi, the tidewater goby, is a federally endangered species endemic to coastal lagoons and estuaries in California. Little is known about the biology of this species in northern California. We conducted a 14-month study (November 2004-December 2005) to determine spawning time, fecundity, habitat utilization, and parasites of a tidewater goby population in Big Lagoon, Humboldt County, CA. Spawning time was determined by monthly length-frequency data and by the presence of gravid females. Spawning occurred throughout the year. Two distinct age classes were observed in June-August 2005. Gravid females were collected in March and May-July 2005. Goby habitat utilization was evaluated using a stratified random sampling technique on a seasonal basis. High goby densities were commonly associated with vegetation in silt and sand substrates. A previously unrecognized microsporidian is described from the musculature of Eucyclogobius newberryi. Spores are ovid with mean length=2.8 um and mean width=1.9 um. The polar tube has 9 or 10 coils in 1 or 2 rows. Development occurs in direct contact with muscle host cell cytoplasm, without xenoma or sporophorous vessicle formation. Phylogenetic analysis of the new species and of 35 other microsporidians known to infect fish using 1115 bp of aligned 16S rRNA gene indicate the new species is most closely related to Kabatana takedai, with 11% sequence divergence. Divergence in morphology and genetic data supports recognition of a new species of microsporidia, Kabatana newberryi n.sp., presently known only from Eucyclogobius newberryi.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Fisheries
- Creator:
- Nickle, Ward B.
- Description:
- It is the intent of this study to simulate the invasion of Cortaderia jubata, jubata grass, into a disturbed second growth redwood forest where the dynamics of the grass and its relationship to the environment are explored through a spatially explicit individual based landscape model. The field of neighborhood approach is used to simulate both the evolution of the forest and the grass. What is of particular interest is the success of the invader in terms of spatial distribution and time with regard to varying disturbance regimes. To assess these qualities, seed dispersal and the field of neighborhood each plant exerts are used to parameterize the model and a measurable plant attribute, self thinning, not included in the model assumptions, is used to test the model's validity.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Mathematical Modeling
- Creator:
- Archibald, Wiley Hall
- Description:
- Harbor seals have been listed as a species likely to benefit from new Marine Protected Areas (MPAs) in California as part of the Marine Life Protection Act. Whereas seals may experience direct and indirect effects from these MPAs as a whole, the impacts of individual MPAs remains unclear. To support the analysis of the impacts of one new MPA located in South Humboldt Bay (SHB), California, I conducted two studies to measure the site fidelity of individual harbor seals within SHB and to describe the changes in distribution and abundance of hauled-out seals inside and outside the new MPA there. From June 2011 through May 2012, I used radio telemetry to assess site fidelity of 28 individually tagged seals. Most seals had high fidelity (>75%) for SHB haul-outs, indicating that these seals are present enough to potentially benefit from added protection. However, the use of radio telemetry proved difficult and costly for long-term data collection. Therefore, weekly visual surveys were implemented beginning in July 2012 to track the habitat use of all seals hauled-out in SHB. There were significant seasonal differences in seal abundance (ANOVA, F5 = 4.047, p < 0.01) and groupings (ANOVA, F5 = 10.06, p <0.01), particularly between the winter and the spring seasons. In addition to highlighting key seasons for additional management and monitoring, these surveys proved more successful and sustainable than radio telemetry for monitoring year-round impacts of the new MPA on harbor seals.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Biology
- Creator:
- Aloe, Echo
- Resource Type:
- Student Research
- Campus Tesim:
- Humboldt
- Department:
- History
- Creator:
- Mattice, Daraxa
- Description:
- Tribal Nations throughout American history have had a complex existence while trying to navigate through the US government’s definition of tribal sovereignty. There is a link between history and continuing issues that are stagnating economic growth within Tribal Nations. Diverse laws and their meanings have had a detrimental effect on tribal people and their land base. This project is about the link between these complexities and the current state of American Indian Nations economic growth. I will look at these laws in a historical context and discuss what tribes are doing economically today.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Business Administration
- Creator:
- Wilkinson, Sarah
- Description:
- The purpose of this project was to build the capacity of a Perinatal and Postpartum Support Network in a county in rural Northern California to effectively engage, cultivate and build up the community supports that address perinatal mental health. The goal of this Network is to raise awareness of the issues that surround perinatal and postpartum mental health and build up the community supports in order to strengthen the families and the community. This project used a participatory change framework, and the ideologies from community capacity building, to enhance the processes of the current Network and subcommittee members to identify and strengthen community relationships, bridge partnerships, bring new participants to the table, and identify already existing community supports. Outcomes of this project will be used to inspire and support future community leaders and to sustain the current efforts of the Network to support and improve maternal mental health in the county.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Social Work
- Creator:
- Besyk, Nichole R.
- Description:
- Plant available phosphorus (P) occurs in anionic forms which become unavailable (retained) when iron and aluminum oxides form insoluble phosphate complexes. P-retention is especially likely to occur under acid conditions in soils containing short range order (SRO; poorly crystalline) materials, namely allophane and imogolite. This set of characteristics is common in volcanic-derived forest soils in Pacific Northwest timber regions. P-retention was investigated in Powellton (Fine-loamy, parasesquic, mesic Andic Haplohumults) and Aiken (Fine, parasesquic, mesic Xeric Haplohumults) soil series from Feather Falls and Whitmore “Garden of Eden” sites, respectively. Some soils received heavy fertilization over multiple years; another set of unfertilized soils were compared as a control. Results show that pHNaF (indicator of SRO materials), soil carbon, and New Zealand P-retention decreased with soil depth in both soils. In near-surface horizons, Feather Falls soil had higher pHNaF, carbon content, and P-retention than the Whitmore soil. Unexpected high P-retention at Feather Falls is probably due to the presence of P-fixing organo-metal complexes in Feather Falls surface horizons. TheWhitmore soil shows higher pHNaF and P-retention than Feather Falls in deep horizons. At Whitmore, the drop in P-retention with depth is attributed to decreasing SRO minerals deeper in the profile; at Feather Falls, a simultaneous drop in carbon and SRO minerals contributes to the pattern of P-retention with depth. Fertilized surface soils at Feather Falls showed ten percent less P-retention than unfertilized soils at that site. Fertilization did not affect P-retention at Whitmore. pHNaF was the single best predictor of P-retention, with other important factors including depth, soil carbon, and soil “redness” (a quantitative measure representing iron content) in a mixed-effects regression of P-retention for these soils.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Natural Resources
- Creator:
- Dockham, Andrea Sue
- Description:
- Morphological changes in the Dry Creek (Sonoma County, California) associated with Warm Spring Dam, have reduced habitat availability for rearing fish, and potentially altered the community structure of benthic invertebrates that form the prey-base for juvenile salmonids. I described and compared the structure of benthic invertebrate assemblages and the diets of juvenile steelhead among four stream reaches of Dry Creek downstream of Warm Springs Dam. I hypothesized that if prey availability contributes to factors restricting the success of juvenile salmonids in mainstem Dry Creek, then diet composition should parallel observed differences in reach-specific relative condition and length of juvenile salmonids. Benthic invertebrate assemblages in Dry Creek displayed a longitudinal trend from Warm Springs Dam to the confluence with the Russian River; however, steelhead diet composition did not correspond with reach-specific benthic invertebrate assemblages as expected. Drift-foraging is likely an important feeding strategy for steelhead in mainstem Dry Creek. Steelhead condition and body length corresponded with reach-specific differences in steelhead diet composition. However, reach-specific differences in energetic cost associated with longitudinal differences in water temperature (water temperature was positively correlated with distance from the dam) may be a greater contributor to differences in steelhead size. The relatively high steelhead summer growth rates, in comparison with similar studies, may result from artificially-sustained summer flows in mainstem Dry Creek. Year-round flows in mainstem Dry Creek maintain stream connectivity during a period when non-regulated streams in Mediterranean climates typically become disconnected, therefore increasing food availability and foraging opportunities.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Fisheries
- Creator:
- Mullin, Stephen M.
- Description:
- The Western Snowy Plover (Charadrius alexandrinus nivosus) is a federally listed threatened species as well as a state listed “species of special concern” in California. Accurate survival estimates are required to determine the best conservation strategies for threatened and endangered species. The population located in Humboldt County, CA was studied for five breeding seasons (2001-2005) and apparent survival for adult and juvenile plovers was estimated using program MARK. In addition, the population structure over this time period was described to determine the importance of immigration. The growth rate of the population was also estimated using the Pradel model and site specific birth and death rates to quantify the importance of immigration. Apparent survival for adult males (φ = 0.64) was greater than that for adult females (φ =0.57) while apparent survival for adults was greater than that for juveniles (φ = 0.30). The estimated annual growth rate using Pradel models demonstrated a stable population (λ = 0.99); however, this included both local recruitment and immigration as sources of new individuals. When calculated algebraically, based on estimates of local recruitment and survival, the growth rate demonstrated a declining population (λ = 0.71), clearly indicating the importance of immigration to the persistence of the population. Source/sink dynamics probably occur in the spatially disjunct populations of Snowy Plovers along the Pacific coast due to differences in habitat quality. However, the Humboldt County population should not be defined as a sink population across all breeding sites. At a smaller scale, sites along gravel bars of the Eel River were closely approaching the recruitment requirements to be classified as source areas whereas beach breeding sites were sink areas. Continued management activities, especially those that were designed to increase productivity (e.g. exclosures) are recommended. Because productivity is a major problem for plovers in this area and due to the success observed in Oregon, population control of predators should be considered. Increased management, such as curtailing the access of off-road vehicles along the more productive gravel bar areas during the breeding season is also recommended.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Wildlife
- Creator:
- Klein, Randy D.
- Description:
- The excavation of road fill from stream crossings on former logging roads is a major focus of the watershed restoration program in Redwood National Park. Channel adjustments in response to winter stormflows were measured on 24 newly excavated stream crossings to identify the relative importance of on site independent variables. Two dependent variables, channel erosion and surficial channel bed armor, were regressed on sets of independent variables related to stream hydraulics and stream bank material properties in two series of regression analyses. In the channel erosion series, the final regression equation incorporated as significant predictors (in order of decreasing predictive importance) total stream power, the percent boulder and cobble content of streambank materials, and the percent stream elevation drop composed of organic debris steps. Of primary importance in explaining the variability in channel erosion was total stream power of the peak flow of the study period, which was directly related to channel erosion. The boulder and cobble content of stream bank materials, inversely related to channel erosion, was second most important among predictors. Because the best fit was obtained using the square of this quantity, it is inferred that the potential for erosion decreases as a power function of increasing coarse fragment content of eroding materials, all other factors being equal. The percent of stream elevation drop composed of organic debris steps was inversely related to channel erosion because it provided for energy dissipation and hydraulic resistance. In the channel armor regression series, the final regression equation incorporated (in order of decreasing predictive importance) total stream power and percent of the stream elevation drop composed of organic debris steps as significant predictors. Being inversely related to channel armor, the presence of organic debris steps partially offset the channel armoring demands of total stream power. To minimize channel erosion following stream crossing excavation, consideration must be given to the relative magnitudes of driving forces (stream power) and resisting forces (coarse fragment content of bank material and level of organic debris control of the stream profile). In proposed excavations where resistance to erosion is anticipated to be low and stream power is expected to be high, consideration should be given to channel protective measures such as installation of check dams, importation of rock armor, or emplacement of organic debris.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Watershed Management
- Creator:
- Williams, Stephanie McKinney
- Description:
- With the rising demands for improvement and accountability required under the No Child Left Behind Act, schools are beginning to see the value of making data-based decisions to dramatically increase student achievement on high-stakes tests. Unfortunately, the information from these end-of-the-year tests often arrives too late to afford teachers the time to analyze the resultant data and make necessary curricular adjustments, both for specific students and groups as a whole. In an effort to make annual yearly progress, many educational agencies are starting to make data-driven decisions to help struggling students make the necessary academic gains to be successful on high stakes tests. In order to assess the Common Core State Standards and ensure that students are meeting these benchmarks, some schools utilize formative assessments called Measures of Academic Progress (MAP), designed by Northwest Evaluation Association. The disaggregated assessment data provided by Measurement of Academic Progress highlight the strengths and weaknesses of every child and provide teachers with the necessary information to target instruction. The aim of this study was to reveal if and how teachers at a highly successful school used assessment data to make instructional decisions, and what impact, if any, this had on the school’s on-going high performing status.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Education
18. Reproductive isolation in five hybridizing species of western gooseberries (Ribes: Grossulariaceae)
- Creator:
- Kalt, Jennifer L.
- Description:
- Five species of western gooseberries (Ribes: Grossulariaceae) hybridize to varying degrees in northwestern California and southwestern Oregon. Pollinator surveys and hand-pollination experiments were conducted to identify reproductive barriers between the species pairs. I found little evidence of isolation due to pollinator behavior, since the five species tended to attract the same pollinators. My attempts to assess the level of post-pollination isolation were hindered by high rates of fruit abortion. Nevertheless, it appears that R. roezlii and R. menziesii are fully interfertile, and that unilateral barriers operate when R. lobbii, which has the longest styles of the set, is the maternal parent in crosses with the other species. Since the level of post-pollination isolation is not correlated with the observed frequency of hybridization in the field, ecological and/or geographical differences may play the most important role in isolating the species.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Biology
- Creator:
- Hanna, Sara K.
- Description:
- This study examined the long-term, post-fire dynamics of sagebrush steppe communities at two burn areas located in Modoc County in northeastern California. Pre and post-fire vegetative cover and herbaceous productivity data were collected at two burn areas across a nearly thirty-year period. The cover and productivity data from the study area were also analyzed with respect to their relationship to the number of post-fire growing seasons and annual weather conditions. As expected, fire removed the woody, shrub component of the plant community and shifted the plant community to an herbaceous, grass-dominated community. Vegetative cover and productivity of herbaceous species increased significantly in the years following the burns. While the invasive annual grasses (primarily cheatgrass, Bromus tectorum) dominated in the plant community in the years immediately following the fires, native perennial grasses overtook the annual grasses after 10 post-fire growing seasons. A substantial amount of the variability in annual grass cover and productivity could be explained by the number of post-fire growing seasons. Annual grass cover and productivity were also significantly influenced by annual variations in weather, particularly fall and winter precipitation. Perennial grass productivity peaked 10 years following the burns, while perennial grass cover reached maximum levels 20 years post-fire. Perennial grass cover and productivity began to decline towards the end of the monitoring period, but were still greater than the pre-fire levels. Perennial grasses appeared to be minimally influenced by annual variations in temperature and precipitation. Both annual and perennial forbs generally increased following the fire, but varied both spatially and temporally. Annual fluctuations in temperature and precipitation explained more of the variation in annual forb cover and productivity than post-fire time. Shrub recovery was slow following the prescribed burns, with minimal shrub cover noted until 10 to 20 growing seasons. Following nearly 30 post-fire growing seasons, sagebrush cover returned to pre-fire levels and was comparable to cover levels to unburned areas. Shrub recovery rates were relatively stable across the study area, and were not influenced by annual variations in temperature or precipitation. By 2009, there was evidence of western juniper returning to both of the burn areas. This indicates that a 30-to-40 year fire return interval might be recommended to reduce western juniper encroachment and to maintain a productive and diverse ecosystem. Even with the relatively small spatial scale of study area, there were significant differences in the post-fire vegetation between the sampling sites. The research confirms that sagebrush steppe plant communities are highly heterogeneous and can vary in their post-fire succession.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Rangeland Resources
- Creator:
- Anguiano, Anna M.
- Description:
- With the growing Latino population in the rural Humboldt County, there is a pressing need for more bilingual services. The purpose of my community project is to find out which service providers in Humboldt County provide bilingual services to monolingual Spanish-speaking clients, and what some of the challenges are for service providers when working with the Latino population in regard to domestic violence issues. My project consisted of distributing questionnaires to service providers to find out about which services are available in the community, the barriers faced by service providers, and what service providers feel they need so they can better met the needs of the Latino Community. The results showed that the major barriers faced by service providers were lack of resources, language, immigration status, and cultural norms. What many of the participants believe is needed within the community is more bilingual services, relevant trainings and education, and culturally appropriate services.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Humboldt
- Department:
- Social Work