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10831. [Article] Epidemiological insights into Armillaria mellea root rot in a managed Ponderosa pine forest
Root rot of ponderosa pine caused by Armillaria mellea was studied in a pine forest that had been under management for 30 years in Klickitat County, Washington. Information sources included disease survey, ...Citation Citation
- Title:
- Epidemiological insights into Armillaria mellea root rot in a managed Ponderosa pine forest
- Author:
- Shaw, Charles G. (Charles Gardner) 1948-
Root rot of ponderosa pine caused by Armillaria mellea was studied in a pine forest that had been under management for 30 years in Klickitat County, Washington. Information sources included disease survey, detailed observation and description of specific disease situations, and examination of roots in situ and removed. Roughly circular infection centers in stands of sapling and pole-sized pines appear to arise regularly from stumps of harvested old-growth trees, some of which have contained viable A. mellea for over 30 years. Distinctive concentric zones caused by the disease mark the infection centers. These zones differ in above-ground appearance, in degree of root decomposition, and in level of infection. Location of a specific zone depends on the interval since cutting of the old-growth tree, while zone width depends on tree sizes in the young stand. Distribution of root material in the interior zones is influenced most strongly by rooting characteristics of the former old-growth trees, and by activity of A. mellea and other decay agents over time, while in the young growth pines of the intermediate zones, time since lethal attack by A. mellea and tree size most influence root condition. Extensive examination of the outer zones disclosed that, in stands containing trees from 3 to 6 inches in diameter, infected root material extended into the healthy-appearing pines 11 ft beyond the outermost dead tree of the infection center, while in stands with trees up to 16 inches in diameter the extent reached 18 ft. A highly significant linear regression with good correlation was found between: 1) the extent of infected root material beyond the outermost dead tree; and 2) mean tree size of the affected stand. Infected root segments from beyond the outermost dead tree, within the region where infected and healthy roots intermingle, produced rhizomorphs, the assumed infection structures, when incubated in bags of moist quartz sand. The expansion rate of infection centers was calculated to be 2. 9 ft (0.88 m) /year. Cross plating techniques indicated that the 1500 acre study area was occupied by a single strain of A. mellea, suggesting that spores are unimportant to the field disease cycle. Current loss to disease in the 1500 acre tract is 35 cu ft per acre per yr, three times the loss in 1957. From 1957 to 1971, the proportion of the area in which disease was detectable remained constant. The increased loss resulted from death of fewer, but larger, trees in 1971. In inoculation tests on ponderosa pine seedlings, A. mellea isolates from old-growth pine stumps and from young pine trees were pathogenic, while isolates from living hardwoods were weakly or nonpathogenic. Reliable methods are described for isolating A. mellea from infected tissues and of testing the capacity of naturally infected root materials to produce rhizomorphs. The abundance of A. mellea over a three year interval following five root removal treatments increased in missed root residues. Resinous lesions were commonly found at the site of A. mellea attack. Rarely does mycelium spread proximally along a living root from one of these lesions, but growth frequently occurs from the lesion toward the root tip following, or concurrent with death of the extremity. Girdling resinous lesions on lateral roots show little effect on tree vigor, while such lesions high on the tap root kill the tree. Soon after tree death, mycelial fans spread under the bark throughout the root system. To obtain insight on how the resinous lesions retard the fungus, tests were conducted on the effects of resin on growth of A. mellea in culture. Autoclaved resin, acetone extracts of resin, water extracts of resin, and non-sterilized resin all stimulated, rather than restricted, growth over non-resin containing media. Removal of phenols from the water extract of resin with polyvinylpyrrolidone destroyed the growth stimulating effect of the resin. Propylene oxide was effective for sterilization of granulated resin.
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10832. [Article] A production function analysis of water resource productivity in Pacific Northwest agriculture
The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This ...Citation Citation
- Title:
- A production function analysis of water resource productivity in Pacific Northwest agriculture
- Author:
- Holloway, Milton L.
The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data source, supplemented by related. U. S. Department of Agriculture publications, and various state publications. Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley).
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10833. [Article] Analysis of selected factors relating to the Neighborhood Youth Corps program in rural counties of Oregon
Purpose of the Study There were two major purposes of this study. The first was to determine which socio-economic and educational factors normally available to Neighborhood Youth Corps personnel were associated ...Citation Citation
- Title:
- Analysis of selected factors relating to the Neighborhood Youth Corps program in rural counties of Oregon
- Author:
- Bigsby, Robert Alexander
Purpose of the Study There were two major purposes of this study. The first was to determine which socio-economic and educational factors normally available to Neighborhood Youth Corps personnel were associated with success and failure in the out-of-school program. The second purpose was to utilize these available socio-economic and educational factors identified as success or failure determiners to construct a mathematical success-failure prediction equation. Procedures Data for 302 enrollees were obtained through a random sampling of terminated out-of-school enrollees. Socio-economic information was extracted from enrollee application forms and files. Educational information was obtained from the last school attended. Stepwise multiple linear regression and classification analyses were performed on data to identify variables contributing most significantly to success or failure. For these analyses, data for enrollees were grouped by marital status, sex, and age. Analyses were performed on separated groups. Variables contributing most significantly to success and failure were utilized to construct an equation for success-failure prediction. Selected Findings 1. A higher proportion of females succeeded in the out-of-school program than did males. Forty-five and one tenth percent of the females succeeded compared to 26.9 percent of the males. 2. Factors affecting success or failure of male enrollees were (a) Enrollee age. Sixteen-year-old male enrollees failed in the program at a rate approximately four times that of older enrollees. (b) Number of siblings in enrollee's family. Male enrollees coming from families with four or more children succeed at a higher rate than enrollees with one, two, or three children. "Only children" failed at a substantially higher rate than others. (c) Highest school grade completed. There was a steady decrease in the failure rate of male enrollees as school grade completed increased. (d) Head of household employment. Single male enrollees living in homes in which the head of household worked part time succeeded at over twice the rate of those living in homes with the head of household working full time. This group also succeeded at a higher rate than those from homes in which the head of household was not working at all. 3. Factors affecting success or failure of female enrollees were: (a) Language spoken in the home. Enrollees speaking Spanish in the home succeeded at a substantially higher rate than those speaking English. (b) Social assistance. Single female enrollees whose families accepted cash welfare payments succeeded at a lower rate than those whose families did not accept welfare. (c) Stated lifetime occupational goal. Single female enrollees stating a skilled lifetime occupational goal succeeded at a higher rate than those stating other lifetime goals. Those stating no lifetime goal or a professional goal failed at a substantially higher rate than others. (d) Family living group. Single female enrollees living with their mothers only succeeded at less than one-half the rate of those living with both parents. (e) Reason for leaving school. Female enrollees who left school for disciplinary reasons failed at a very high rate. (f) Enrollee age. Sixteen-year-old female enrollees tended not to succeed at as high a rate as 17, 18, 19, and 20 year-olds. 4. Accurate prediction of both success and failure was not possible for male enrollees and married or divorced females, 5. It was possible to correctly predict success and failure in the program of single female enrollees approximately 75 percent of the time by employing five socio-economic factors. 6. An equation was developed for predicting success or failure of single female enrollees. The following factors were employed in this prediction: (a) language spoken in home, (b) family living group, (c) reason for leaving school, (d) welfare, (e) lifetime occupational goal.
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10834. [Article] Volcanic stratigraphy of the Deschutes Formation, Green Ridge to Fly Creek, north-central Oregon
About 225 lava flows and ash-flow tuffs of the Deschutes Formation (DF) were mapped at Green Ridge. The units fill east-trending paleovalleys which "sky-out" westward and dip east; the eastward dip of ...Citation Citation
- Title:
- Volcanic stratigraphy of the Deschutes Formation, Green Ridge to Fly Creek, north-central Oregon
- Author:
- Conrey, Richard M.
About 225 lava flows and ash-flow tuffs of the Deschutes Formation (DF) were mapped at Green Ridge. The units fill east-trending paleovalleys which "sky-out" westward and dip east; the eastward dip of the units decreases as they are traced eastward. The source of the units was west of Green Ridge as evidenced by the increase in the number of ash-flow tuffs and lava flows in the DF from east to west toward Green Ridge, and the presence of viscous silicic lavas and lag deposits in ash-flow tuffs on the west flank of Green Ridge. The exposed DF section at Green Ridge is 1400 feet thick, and consists mainly of basaltic andesites with subordinate diktytaxitic basalts, andesites, dacites, aphyric basaltic andesites and andesites rich in Fe and Ti, ash-flow tuffs, and sediments. The upper 400 feet of the section is devoid of ash-flow tuffs and dacites. Nine paleomagnetic polarity intervals, five normal and four reversed, are recognized in the section; tentative correlation of these intervals with the magnetic time scale suggests that the oldest DF unit exposed at Green Ridge is 6.5 Ma, and the youngest 4.4 Ma. The DF units at the crest, and west of Green Ridge are cut by at least five N- to N13W-trending, down-to-the-west normal faults in a zone about five miles wide. These faults were possibly active as much as 5 Ma; the developing faults may have provided structural pathways for the ascent of the mafic lavas in the upper 400 feet of the section. The faulting which created the Green Ridge escarpment was probably finished by 3 Ma, and perhaps earlier. The presence of dense, Fe- and Ti-rich lavas throughout the DF section implies that magmas had relatively easy access to the surface during DF time (7.6-4.4 Ma), which suggests that the E-W extensional tectonism that culminated in the formation of the Green Ridge faults was present throughout deposition of the DF. The major element chemistry of DF diktytaxitic basalts, basaltic andesites, and andesites appears to change regularly with Ti02 content, as shown by decreasing CaO/FeO* (FeO* = total Fe expressed as FeO) with increasing Ti02, and by decreasing A1203 with increasing Ti02 at constant MgO content. The basalts and basaltic andesites with the lowest Ti02 contents also have the lowest alkali contents. These chemical trends appear to be caused by plagioclase, with subordinate olivine, fractionation, and are consistent with the fact that plagioclase and olivine are virtually the only phenocryst minerals in the mafic DF rocks. It is likely that the diktytaxitic basalt with the lowest Ti02 content is a parental magma. Fractionation may account for the chemical variations within the mafic rock groups considered separately, but the progression from basalt to andesite appears to be the result of mixing of silicic and mafic magmas. The chemistry of the rocks, especially the CaO/Al203 ratios, is consistent with such mixing, as is the petrography; opaque minerals are very late crystallizers in the basalts and basaltic andesites, and there is increasing evidence for magma mixing in the series basalt through andesite. Such evidence includes multiple plagioclase populations in the same rock, both of which are resorbed, and resorbed pyroxenes and amphiboles. Three flows of plagioclase megacryst-bearing basaltic andesite occur near the top of the DF section. The plagioclase megacrysts are up to 5 cm in length, commonly contain apatite inclusions, and resemble the plagioclase in anorthosite bodies. Ilmenite megacrysts are also present. The megacrysts and the presence of highly plagioclase-fractionated aphyric lavas rich in Fe and Ti in the DF suggest that anorthosite bodies are present beneath the north-central Oregon Cascade Range. Two xenoliths of partly melted cordierite-sillimanite-quartz granulite gneiss were found in a DF ash-flow tuff. The xenoliths demonstrate that granulite-grade metamorphism and at least local partial melting of the lower crust took place beneath the north-central Oregon Cascades.
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10835. [Article] Oregon Fish Passage Barriers
Abstract -- The Oregon Fish Passage Barrier Data Standard (OFPBDS) dataset contains barriers to fish passage in Oregon watercourses. Barriers include the following types of natural or artificial structures: ...Citation Citation
- Title:
- Oregon Fish Passage Barriers
Abstract -- The Oregon Fish Passage Barrier Data Standard (OFPBDS) dataset contains barriers to fish passage in Oregon watercourses. Barriers include the following types of natural or artificial structures: bridges, cascades, culverts, dams, debris jams, fords, natural falls, tide gates, and weirs. The OFPBDS dataset does not include structures which are not associated with in-stream features (such as dikes, levees or berms). Barriers are structures which do, or potentially may, impede fish movement and migration. Barriers can be known to cause complete or partial blockage to fish passage, or they can be completely passable, or they may have an unknown passage status. This dataset complies with version 1.1 of the OFBPDS data standard. New optional attributes have been added to describe fish passage barrier feature modifications, to describe supplementary information (via a comments field) and also to linear reference the barrier features to the National Hydrography Dataset. The OFPBDS dataset now contains over 40,000 barrier features from 19 separate sources including: Oregon Department of Fish and Wildlife (ODFW), Oregon Department of Transportation (ODOT), Oregon Department of Water Resources (OWRD), Oregon Department of Forestry (ODF), Oregon Watershed Enhancement Board (OWEB), Oregon Department of Land Conservation and Development (DLCD) US Bureau of Land Management (BLM), US Forest Service, Nez Perce Tribe, Benton SWCD, Washington county, Lower Columbia River Estuary Partnership and watershed councils representing the Rogue, Umpqua, Siuslaw, Santiam, Calapooia, Clackamas and Scapoose basins. The Data Steward obtained fish passage barrier data from multiple data originators between 2008 and 2015, collaborated with them to develop inclusion / exclusion criteria and dataset specific crosswalks for converting data from its original data structure to the structure of the OFPBDS. The data were then converted into the OFPBDS format and analyzed for duplication with existing OFPBDS barrier features. Where duplicates were identified, depending upon the scenario, one feature was either chosen over the other or in some cases attributes from different sources are combined. Source information is retained for each feature. The data were then loaded into the OFPBDS database. Barrier features were linear referenced (Framework Hydro only which is outside of the standard) and the corresponding optional attribute elements were populated. The data conversion, duplication reconciliation and linear referencing protocols are documented in the Oregon Fish Passage Barrier Data Management Plan. A separate dataset containing fish passage barrier features that have been completely removed or replaced (e.g. dam removals and culvert replacements) is published simultaneously with the OFPBDS dataset. The OFPBDS database is the most comprehensive compilation of fish passage barrier information in Oregon however, it does NOT represent a complete and current record of every fish passage barrier within the state. Efforts to address deficiencies in data currency, completeness and accuracy are ongoing and are often limited by lack of sufficient resources. Attributes (including key attributes such as fish passage status) are often unknown or incomplete. Consistency in attribution also varies among data originators. Field verification of barrier features and their attributes will be an important component to making this dataset current, comprehensive and accurate. Fish passage status is a key attribute. Many barrier features have an unknown passage status. For other features, the passage status may have changed since it was originally documented. Note that this metadata file is best viewed in ArcCatalog. Documentation for the OFPBDS can be found online at http://www.oregon.gov/DAS/EISPD/GEO/docs/bioscience/OregonFishPassageBarrierDataStandardv1dot1.pdf.
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10836. [Article] Hydrogeochemical Characterization of the Alvord Valley Known Geothermal Resources Area, Harney County, Oregon
The Alvord Valley Known Geothermal Resources Area (KGRA) , located east of the Steens Mountain-Pueblo Mountains fault block in southeastern Oregon, is within the northern Basin and Range province. This ...Citation Citation
- Title:
- Hydrogeochemical Characterization of the Alvord Valley Known Geothermal Resources Area, Harney County, Oregon
- Author:
- St. John, Anna Maria
- Year:
- 1993
The Alvord Valley Known Geothermal Resources Area (KGRA) , located east of the Steens Mountain-Pueblo Mountains fault block in southeastern Oregon, is within the northern Basin and Range province. This investigation focuses on three thermal areas in the Alvord Basin: Borax Lake and the hot springs north of Borax Lake, Alvord Hot Springs and Mickey Springs. Mickey Springs and the springs north of Borax Lake are boiling at the surface (94 and 95° C, respectively). Inflow temperatures to Borax Lake, measured at a depth of 30 m, are greater than 100° C. Surface temperatures for Alvord Hot Springs and a flowing well northeast of Borax Lake are 78 and 59° C, respectively. Thermal fluids issue from Quaternary lacustrine and alluvial deposits. While silica sinter deposits are present at all three thermal areas, sinter is not presently being deposited. Minor calcite is being deposited at the springs north of Borax Lake. The springs discharge from N to NEstriking, high-angle, basin-bounding faults along the base of Steens Mountain and Mickey Mountain and NE-striking intrabasinal faults south of Alvord Lake. The thermal waters are dilute sodium-bicarbonate waters with significant amounts of sulfate and chloride. Conservative element plots (B, F, and Li vs. Cl) indicate good correlation between Cl and the other conservative elements. These correlations could result from mixing of thermal water with a dilute cold water or fluid evolution due to increased fluid-rock interaction, evaporation, and steam loss due to boiling. The small variations in chloride concentrations of thermal fluids during the sampling period argues against mixing of thermal fluids with cold water. The geothermal system is a hot-water rather than a vapordominated system. The ỎD content of thermal fluids is similar to the ỎD content of local cold water wells, springs, basinal pore fluids at a depth of 4 to 5 m, and perennial streams. Similarities in ỎD values indicate recharge for geothermal fluids is precipitation from the Steens Mountain fault block. The Ỏ18 content of thermal fluids is shifted 2 to 3°/oo to the right of the world meteoric water line indicating fluid-rock interaction at elevated temperatures in the reservoir. Tritium contents indicate relatively long residence times and/or low-velocity circulation of meteoric water through basement rocks. Values range from 0 to 0.25 T.U. The application of two end-member models, which calculate fluid residence times, generate a minimum of 57 years and a maximum of greater than 10,000 years. Estimated reservoir temperatures based on cation and silica geothermometry are between 170 and 200°C. Oxygensulfate isotope geothermometer estimates indicate reservoir temperatures between 198 and 207' C for Borax Lake and Alvord Hot Springs. Mickey Springs and a flowing well northeast of Borax Lake yield temperature estimates of 168 and 150° C, respectively. These values indicate partial reequilibration of the isotopic system. The Ỏ13C contents of carbon dioxide and methane of gas discharges from the thermal areas are similar to geothermal fluids from other sites. The Ỏ13C of methane indicate "normal" geothermal methane for Alvord Hot Springs and Mickey Springs (-27.8 and -27.6, respectively). The Ỏ13C of CH4 for springs north of Borax Lake (-33.6) indicates a small amount of thermogenic methane may be contributed by thermal alteration of organics in basinal sediments. The Ỏ13C contents for C02 at Alvord Hot Springs and Borax Lake are within the range expected for atmospheric, fumarolic, or mantle derived C02 (-6.5 and -6.6, respectively). The Ỏ13C content of C02 from Mickey Springs is isotopically lighter than gas released from fumaroles or the mantle (-9.4). N2/Ar ratios for Mickey Springs and Borax Lake gases (39.2 and 40.8, respectively) indicate interaction with airsaturated ground water during flow through the the zone of aeration. Helium is enriched relative to Ar and N2 in gas discharges from Alvord Hot Springs, indicating longer fluid residence times and/or increased crustal interaction at high temperatures. Ratios of B/Cl indicate the fluid reservoir is hosted in volcanic rocks. The Li/Cs ratios for the Borax Lake thermal area are consistent with a reservoir located in rhyoli tic rocks. The 228Ra/226Ra content of Borax Lake thermal fluids (1.14 ± 0.13 dpm/kg) indicates interaction with volcanic rocks for Borax Lake. The 228Ra/226Ra content of thermal fluids from Alvord Hot Springs and Mickey Springs (0.38~0.02 and 0.17 ~ 0.09) are lower than those expected for volcanic rocks and may indicate local uranium accumulation in the reservoir or zones of upflow. The 87Sr / 86Sr values for thermal waters and stratigraphic uni ts indicate the fluid reservoir is located in volcanic rocks beneath Steens Basalt. Equilibration of fluids in these units argues for thermal water circulation depths of 2 to 2.5 km in the Borax Lake thermal area, greater than 3 km in the Alvord Hot Springs area and 1 to 2 km in the Mickey Springs area. Data presented in this study do not preclude a single large deep reservoir system discharging at these three thermal areas in the Alvord basin. Differences in the chemical and isotopic composition of discharge from the three thermal areas are produced during upf low from the reservoir. During upflow, thermal waters follow a complex pathway of vertical and lateral fractures which includes short residence times in shallow reservoirs before reaching the surface. Boiling, mixing with condensate, oxidation, mixing with 1-3% tritium-bearing, near-surface cold water, relative differences in flow rate and volume, and slow cooling without vigorous boiling are processes that modify fluid composition during upflow from the deep geothermal reservoir.
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10837. [Article] Women and Resistance in the African Diaspora, with Special Focus on the Caribbean (Trinidad and Tobago) and U.S.A.
American history has celebrated the involvement of black women in the "underground railroad," but little is said about women's everyday resistance to the institutional constraints and abuses of slavery. ...Citation Citation
- Title:
- Women and Resistance in the African Diaspora, with Special Focus on the Caribbean (Trinidad and Tobago) and U.S.A.
- Author:
- Washington, Clare Johnson
- Year:
- 2010
American history has celebrated the involvement of black women in the "underground railroad," but little is said about women's everyday resistance to the institutional constraints and abuses of slavery. Many Americans have probably heard of and know about Harriet Tubman and Sojourner Truth - two very prominent black female resistance leaders and abolitionists-- but this thesis addresses the lives of some of the less-celebrated and lesser-known (more obscure) women; part of the focus is on the common tasks, relationships, burdens, and leadership roles of these very brave enslaved women. Resistance history in the Caribbean and Americas in its various forms has always emphasized the role of men as leaders and heroes. Studies in the last two decades Momsen 1996, Mintz 1996, Bush 1990, Beckles and Shepherd, Ellis 1985, 1996, Hart 1980, 1985) however, are beginning to suggest the enormous contributions of women to the successes of many of the resistance events. Also, research revelations are being made correcting the negative impressions and images of enslaved women as depicted in colonial writings (Mathis 2001, Beckles and Shepherd 1996, Cooper 1994, Campbell 1986, Price 1996, Campbell 1987). Some of these new findings portray women as not only actively at the forefront of colonial military and political resistance operations but performed those activities in addition to their roles as the bearers of their individual original cultures. Their goal was achievement of freedom for their people. Freedom can be seen as a magic word that politicians, propagandists, psychologists and priests throw around with ease. Yet, to others freedom has a different meaning which varies with the individual's sense of associated values. Freedom without qualification is an abstract noun meaning, "not restricted, unimpeded", or simply, "liberty"; but when it is concretized in individual situations its meaning is narrowed, and it becomes clear that no one can be fully free. Yet the love of freedom is one of our deepest feelings, a truly heartfelt cry, freedom of wide open spaces, liberty to enjoy the taste, in unrestricted fashion, of the joys of nature, to live a life free from external anxieties and internal fears; freedom to be truly ourselves. All living creatures, even animals seem to value their freedom above all else. Enslaved people were not submissive towards their oppressors; attempts were made both subtly, overtly and violently to resist their so-called "masters" and slavery conditions. Violent and non-violent resistance were carried out by the enslaved throughout colonial history on both sides of the Atlantic, and modern historical literature shows that women oftentimes displayed more resistance than men. Enslaved Africans started to fight the transatlantic slave trade as soon as it began. Their struggles were multifaceted and covered four continents over four centuries. Still, they have often been underestimated, overlooked, or forgotten. African resistance was reported in European sources only when it concerned attacks on slave ships and company barracoons, but acts of resistance also took place far from the coast and thus escaped the slavers' attention. To discover them, oral history, archaeology, and autobiographies and biographies of African victims of the slave trade have to be probed. Taken together, these various sources offer a detailed image of the varied strategies Africans used to defend themselves and mount attacks against the slave trade in various ways. The Africans' resistance continued in the Americas, by running away, establishing Maroon communities, sabotage, conspiracy, and open uprising against those who held them in captivity. Freed people petitioned the authorities, led information campaigns, and worked actively to abolish the slave trade and slavery. In Europe, black abolitionists launched or participated in civic movements to end the deportation and enslavement of Africans. They too delivered speeches, provided information, wrote newspaper articles and books. Using violent as well as nonviolent means, Africans in Africa, the Americas, and Europe were constantly involved in the fight against the slave trade and slavery. Women are half the human race and they're half of history, as well. Until recent years, Black women's history has been even less than that. Much work has been done studying the lives of slaves in the United States and the slave system. From elementary school in the USA on through college we are taught the evils of slavery that took place right here in the Land of the Free. However, how much do we know about the enslaved in other places, namely the Caribbean? The Caribbean was the doorway to slavery here in the New World, and so it is important that we study the hardships that enslaved people suffered in that area. Slaves regularly resisted their masters in any way they could. Female slaves, in particular, are reported to have had a very strong sense of independence and they regularly resisted slavery using both violent and non-violent means. The focus of my research is on the lives of enslaved women in the Caribbean and their brave resistance to bondage. Caribbean enslaved women exhibited their strong character, independence and exceptional self worth through their opposition to the tasks they performed in the fields on plantations. Resistance was expressed in many different rebellious ways including not getting married, refusing to reproduce, and through various other forms as part of their open physical resistance. The purpose of this project is to identify the role enslaved women in both the Caribbean and the USA played in some of the major uprisings, revolts, and rebellions during their enslavement period. The research identifies individual female personalities, who played key roles in not only the everyday work on plantations, but also in planning resistance movements in the slave communities. This study utilizes plantations records, archival material, and official sources. Archival records from plantations located in archives and county clerks' offices; interviews with sources such as researchers and experts familiar with the plantations of slave communities in designated areas; and research in libraries, as well as other sources, oral histories, written and oral folklore, and personal interviews were used as well.
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10838. [Article] Overstory Structure and Community Characteristics of Oregon Ash (Fraxinus latifolia) Forests of the Willamette Valley, Oregon
As species of ash trees become increasingly threatened worldwide by exotic pests and pathogens, it is important to develop descriptions of their ecologies that help guide the conservation and restoration ...Citation Citation
- Title:
- Overstory Structure and Community Characteristics of Oregon Ash (Fraxinus latifolia) Forests of the Willamette Valley, Oregon
- Author:
- Prive, Sean
As species of ash trees become increasingly threatened worldwide by exotic pests and pathogens, it is important to develop descriptions of their ecologies that help guide the conservation and restoration of forests in which they are a major component. Oregon ash (Fraxinus latifolia) is a dominant tree species in wetland forests of the Willamette Valley, Oregon. It is potentially threatened by the emerald ash borer, an exotic forest insect that is expanding in range in North America. The arrival of the emerald ash borer in the western United States is expected to cause high rates of Oregon ash mortality, which will likely highly alter structural and compositional characteristics of regional riparian and wetland forests. To investigate the structural development and plant community dynamics of Willamette Valley Oregon ash forests, I quantified species structure and composition for both overstory and understory communities along gradients of stand age and soil moisture. Community Type Wetland Index (CTWI) scores were calculated for each plot by multiplying plot-level species abundances by the national wetland indicator value for each species, and were used as an approximation of local soil moisture regimes. Ash forests and early seral savannas were sampled in 102 plots within 11 wetlands between Lane and Washington Counties, Oregon. Early seral wetland savannas were dominated by herbaceous vegetation and had highly variable ash and other tree species recruitment. Young ash forests initiated on wetland sites that were formally maintained as savannas via anthropogenic disturbance. Structural development in these forests generally followed previously described post-disturbance stages: stem exclusion, understory initiation, young multi-strata, and old growth. As stands aged, tree densities decreased and mean tree diameter increased. Mean stand densities (for trees >5 cm at 1.3 m height) ranged from 1727 trees per hectare in stem exclusion stands to 348 in old growth stands, while mean tree diameter increased from 12 to 32 cm between those same stages. Furthermore, understory vegetation shifted from herbaceous to shrub and understory tree species. Oregon ash had the greatest relative dominance of all tree species at all stages of structural development. Oregon white oak (Quercus garryana) was the only other tree species commonly found in forest canopies, though it was typically far less abundant than Oregon ash. Plots in which oak was present had a greater depth to soil mottling, indicating a lower depth to the annual high water table. Oregon ash was also the most commonly regenerating tree species in all stages of structural development, and nearly 70% of ash regeneration was vegetative. Other tree regeneration was typically restricted to understory species, especially cascara (Rhamnus purshiana) in forests and hawthorn (Crataegus spp.) in savannas. Forest structural diversity increased between each stage of development. In total, 216 plant species were identified. Of these, 147 were found in forest plots. Community composition differed significantly between forests and savannas, and between "young" (stem exclusion and understory initiation) plots and "old" (young multi-strata and old growth) plots. Nonmetric multidimensional scaling (NMS) indicated that, for all wetland plots, the environmental variables most highly correlated with community composition were CTWI scores and canopy cover. For forest plots only, NMS indicated that CTWI scores and stand density were the environmental variables most related to patterns in community composition. Species richness was not correlated with canopy cover, but was negatively correlated with CTWI scores. Exotic species cover was negatively correlated with canopy cover, but was not correlated with CTWI scores. Exotic species composition was dependent on both canopy cover and CTWI scores. On wet sites, reed canary grass (Phalaris arundinacea) was particularly abundant, and was associated with low species richness. On drier sites, common exotic species included trees and shrubs such as blackberries (Rubus spp.), exotic roses (Rosa spp.), single-seeded hawthorn (Crataegus monogyna), and common pear (Pyrus communis) as well as several grass and forb species. The results of this study suggest that, although overstory tree communities are characterized by low diversity, Oregon ash forests are important for landscape-scale structural and plant community diversity in Willamette Valley wetlands. However, overstory tree communities lack diversity; Oregon ash appears to be both an early seral, colonizing species in open wetlands and a climax species that is capable of regenerating under a closed canopy. Few other trees are present regionally that are capable of maintaining a forested state in wetlands. Furthermore, closed canopy Oregon ash forests may suppress exotic species spread, and in the absence of management, overstory ash mortality may lead to increased exotic plant cover. Regardless of future forest health threats, intact Oregon ash forests, like other regional wetland-types, are currently few and limited in extent and should be considered a conservation priority.
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Detailed geologic mapping in the Mormon Mountains and new geophysical data provide significant insight into contractional and extensional tectonics in southern Nevada, southwest Utah, and northwest Arizona. ...
Citation Citation
- Title:
- Structure of the southern Mormon Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona
- Author:
- Carpenter, James Anthony
Detailed geologic mapping in the Mormon Mountains and new geophysical data provide significant insight into contractional and extensional tectonics in southern Nevada, southwest Utah, and northwest Arizona. The rocks in the region were complexly deformed during two distinct tectonic episodes. Numerous interrelated events occurred within each episode. The first tectonic episode, related to the Sevier orogeny, was characterized by east-west crustal shortening which culminated in thin-skinned decollement style folding and thrusting during the Cretaceous. The Virgin-Beaver Dam Mountains anticline, a Laramide-type basement-involved uplift, represents the only thick-skinned contractional structure in the region. The second tectonic episode, related to basin-range rifting, was characterized by east-west crustal extension which was accommodated by high-angle normal faults, with dips averaging 60 degrees, in the brittle upper crust. In this area, basin-range rifting initiated in the Oligocene and continued to Recent time. Relations in the North Muddy Mountains in southern Nevada suggest that the Muddy Mountain thrust sheet advanced and overrode the Weiser syncline during the Cenomanian and may have continued to advance in Turonian time. In the southern Mormon Mountains, the Cambrian Bonanza King Formation lies in the hanging wall flat position in thrust contact with the overturned Petrified Forest Member of the Triassic Chinle Formation at the footwall ramp. The thrust sheet advanced eastward more than 30 km from the place of origin. Thrust imbrication, and probably the formation of hanging wall horses, likely occurred as the Muddy Mountain thrust sheet encountered and ascended up the footwall ramp zone (composed largely of competent carbonate rocks) where slices of the thrust sheet (hanging wall horses) splayed of f and accreted to the footwall ramp zone. A detailed retrodeformable (balanced) regional structure section suggests that fold-thrust shortening at the latitude of the Mormon Mountains is a minimum of about 26%. Extension-related structures overprint older fold-thrust structures in the Mormon Mountains. The west-plunging east-trending Candy Peak syncline is one of a family of fold structures related to basin-range rifting. The syncline formed in pre-Miocene time in association with the northeast-striking Reber Mountain normal fault directly north and the northeast-striking Dry Canyon right-lateral strike-slip fault directly south. The Tortoise Flat synform, which lies southeast of the Dry Canyon fault, developed in Miocene and possibly Pliocene time by right-lateral flexure of early Miocene Horse Spring beds as a result of drag associated with the Dry Canyon fault. The Dry Canyon fault and the Tortoise Flat synform are interpreted to be part of the right-lateral Moapa Peak-Reber Mountain shear zone system in the southern Mormon Mountains. Therefore, the time of formation of the Moapa Peak-Reber Mountain shear zone system is pre-Miocene to possibly Pliocene. The shear zone system formed in response to different amounts of west-directed extension-related movement of the hanging wall block of the high-angle Virgin Beaver Dam Mountains fault, which initiated in the Oligocene. From this, the timing of the Moapa Peak-Reber Mountain shear zone, system is interpreted as Oligocene to Miocene, and possibly Pliocene. The interpretation of 261 km of seismic reflection sections suggests that large-displacement high-angle normal faults, typically with 60 degrees of dip, control horst and graben structure and accommodate extension by simple shear in the upper brittle crust. Such faults likely extend to depths of 15 to 18 km. Below this depth extension is thought to be accommodated by penetrative ductile deformation. A detailed retrodeformable (balanced) regional structure section suggests that basin-range extension at the latitude of the Mormon Mountains is about 17%. The Virgin-Beaver Dam Mountains high-angle normal fault is a large-displacement master fault in the area, having more than 8,000 in of normal vertical separation at the latitude of the Virgin Valley basin depocenter. Miocene doming and uplift of the Mormon Mountains occurred in response to displacement on the Virgin-Beaver Dam Mountains fault. The Virgin Valley basin formed as the hanging wall block downdropped, and the Mormon Mountains dome formed by relative uplift at the opposite end of the hanging wall block. Half-grabens, and tilted, folded, and faulted range blocks characterize basin-range crustal structure. Depositional growth relations are interpreted in basins from fanning-upward reflector geometry, and the wedge-shape of Oligocene to Recent syntectonic basin-fill sediments. Non-overlapping opposing east- and west-tilted half-grabens compose the Meadow Valley-California Wash basin. Seismic sections, gravity data, well data, and geologic mapping demonstrate that the Mormon Peak, Tule Springs Hills, and Beaver Dam/Castle Cliff "detachments," which were thought to be rooted low-angle normal faults, do not exist. The Mormon Peak and Beaver Dam/Castle Cliff low-angle normal faults are denudational fault planes below gravity slid masses. The widely distributed translocated Paleozoic blocks, which were thought to be remnant pieces of large hanging wall sheets ("extensional allochthons"), are disjunct rootless gravity slide blocks of minor tectonic significance. A large number of these rootless slide blocks lie on Pliocene and Quaternary basin-fill deposits. The Muddy Mountain-Tule Springs thrust, of Sevier age, was not reactivated as a crustal penetrating Tule Springs Hills low-angle normal fault, but is affected by small-scale gravity slide features. Rootless gravity slide blocks, secondary features to high-angle normal faults, commonly occur from instability as a result of the loss of lateral support induced by block faulting and the associated erosion of range blocks.
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10840. [Article] Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming
Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The ...Citation Citation
- Title:
- Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming
- Author:
- LeBeau, Chad W.
Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The University of Wyoming joined this collaborative effort in January 2010, and the National Wind Coordinating Collaborative joined the effort in March 2011. The overall goal of the research was to establish the population-level effects of wind energy development on female sage-grouse seasonal habitat selection and demography. This study represents the only situation in the US where the responses of greater sage-grouse to the infrastructure associated with a wind energy development has been investigated. Our primary objective was to discern the relationship between sage-grouse nest, brood-rearing, and summer habitat selection patterns and survival parameters and the infrastructure of an existing wind energy facility. The Seven Mile Hill (SMH) study area was located north of Interstate 80 and south of the Shirley Basin in Carbon County, Wyoming, US. A control and treatment area was included in the SMH study area, with boundaries of each of these areas determined from lek locations and radio-marked female sage-grouse distributions. The Seven Mile Hill Wind Energy Facility (SWEF; located in the treatment area) consisted of 79 General Electric 1.5-MW wind turbines and approximately 29 km of access roads. The facility became fully operational in December 2008. In addition to the SWEF, other anthropogenic features present in this portion of the study area included approximately eight km of paved roads and 26 km of overhead transmission lines. The control study area had no wind turbines and was adjacent to the SWEF and south of US Highway 30/287. There were approximately 50 km of paved roads and 17 km of overhead transmission lines in this area. The treatment area had four leks that had an average distance of 1.93 km from the nearest SWEF turbines (range = 0.53 to 4.15 km), while the control group consisted of 6 leks with an average distance of 10.99 km from the nearest SWEF turbine (range = 7.09 to 16.16 km). We captured and radio-equipped 346 (160 treatment; 186 control) female sage-grouse within an area consisting of a wind energy development and a control area absent of wind energy development in southeastern Wyoming from 2009–2014. We relocated each radio-marked female approximately twice a week during the nesting, brood rearing, and summer periods. We developed a suite of anthropogenic, vegetation, and environmental covariates to estimate habitat selection and survival for all sage-grouse during the nesting, brood rearing, and summer periods. We used a discrete choice habitat selection model to estimate the relative probability of sage-grouse nest site, brood-rearing, and summer habitat selection within both the control and treatment areas during the post-development period. We did not detect a negative impact of the wind energy facility on nest site selection during the study period. Sage-grouse rearing broods generally avoided suitable brood-rearing habitat near anthropogenic infrastructure that includes wind energy development, major paved roads and transmission lines. Although avoidance was consistent across the years of our study, avoidance of wind turbines was more pronounced in 2012-2014 compared to 2009-2011, suggesting a lag period in the ultimate population-level response to the development of a wind energy facility. Although distance to turbine was not strongly associated with summer habitat selection, the percentage of disturbance associated with wind energy infrastructure did appear to influence summer habitat selection. In addition, we estimated survival during each seasonal period to estimate the effect of the SWEF on population fitness. The SWEF did not have a negative effect on sage-grouse nest survival within the study area over the six-year period, and nest survival did not differ between nests of females captured at treatment and control area leks over the study period. The SWEF did not have a negative effect on sage-grouse brood survival within the study area over the six-year period. Survival was related to habitat features and anthropogenic features that have existed on the landscape for >10 years. Lastly, the SWEF did not have a negative effect on female sage-grouse summer survival within the study area over the six-year period. After controlling for annual and natural variability, we observed a positive effect of the SWEF on female survival when the percentage of disturbance within 0.81 km of a sage-grouse location increased from 0% to 3%. Our study is the first to estimate the impacts of wind energy development on sage-grouse habitat selection and fitness parameters. Female sage-grouse selection of seasonal habitats was variable relative to the infrastructure associated with wind energy facility, but fitness parameters did not appear to be influenced to a great degree by the infrastructure. This pattern of effect is similar to greater prairie-chicken response to a wind energy facility in Kansas but opposite of sage-grouse response to oil and gas development. Ideally, we would have preconstruction data to identify changes in the population and decipher mechanisms in sage-grouse response to infrastructure; however, we are confident that if such impacts to habitat selection and survival did occur then we would have been able to detect these changes over the 6-year study period. The lack of other studies investigating impacts from wind energy development to sage-grouse habitat selection and survival limits our ability to make inferences about the cumulative impacts of wind energy development on sage-grouse, but we were able to describe some of the impacts that wind energy developments may have on sage-grouse populations. Although we attempted to account for possible confounding factors, there is the chance that we did not detect important interactions between environmental features and habitat selection and survival patterns. Future wind energy developments should consider the potential impacts of wind energy development on sage-grouse habitat selection patterns and survival parameters. We recommend facilities similar in size that occupy similar habitats as our study be placed 1.20 km from any occupied sage-grouse nesting, brood-rearing, or summer habitats. We recommend that future research consider predator-prey mechanisms by estimating both avian and mammalian predator densities to better understand the impacts of wind energy development on sage-grouse fitness parameters and to develop appropriate mitigation measures.