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Evaluating the impact of community forestry practices in Sumatra Island, Indonesia
No full textManaging common-pool resources has always been a local challenge with global implications. Community-based forest (CBF) management is often cited as one of the answers to better manage forests while providing livelihood to local communities and global benefits in mitigating climate change. This study investigates the extent to which Community Forests (CF) scheme in Indonesia are managed to provide livelihood benefits for rural population while exercising sustainable forest management. First, we applied a quantitative approach to empirically compare forest cover changes within watershed protection forests with and without CF units and also against those within conservation forests. We measured forest cover changes between 2007 and 2016 in Lampung province in Indonesia where CF units were established earlier than other provinces. We used remote sensing data of annual tree cover loss and propensity score matching to reduce possible confounding effects. We found that CF concessions within watershed protection forests in Lampung province have managed to maintain forest cover loss in relatively low levels compared to those that are not managed by communities. This result shows that generating added economic benefits and improving local community’s access to forest resources do not necessarily lead to degradation of the forests. Second, we conducted a qualitative assessment through focus group discussions with farmers in two CF units with distinct biophysical characteristics to investigate the impact of different biophysical characteristics on the performance of each CF unit in achieving its goal of generating livelihood benefits with sustainable forest management. We found that the performances of each CF is fundamentally affected by its biophysical circumstances and economic benefits that community members can drive from non-timber forest products. Designation of community forestry areas should take into account biophysical characteristics of CF locations to support multiple land use scenarios that can provide ample livelihood benefits for local communities. Areas with a low percentage of tree cover, that support multiple livelihood scenarios, present the biggest opportunity to restore forests while providing livelihood benefits with the lowest risk profile for future forest degradation. This safeguard measure would improve the likelihood of community forests in achieving the dual mandates of improving livelihood of local communities while protecting and restoring remaining forests
Unmanned aerial vehicles for estimating forest canopy fuels in ponderosa pine forest
Get PDFForests in the southwestern United States are becoming increasingly susceptible to large wildfires with significant environmental and economical impacts. As a result, forest land managers are planning and conducting forest fuel reduction treatments, in which spatial forest fuels and structure information are necessary, but currently have coarse spatial resolution and limited accuracies. This study tested the feasibility of using an unmanned aerial vehicle (UAV) with a multispectral sensor for estimating forest canopy fuels and structure in a southwestern ponderosa pine forest. The UAV-derived 2D multispectral orthomosaic images and 3D Structure-from-Motion point clouds were used to estimate canopy cover, canopy height, tree density, canopy base height, and canopy bulk density. The estimates were validated with field measurements within 57 plots, 10 x 10 m in dimension, and commonly used aerial photography from the National Aerial Imaging Program with 1 m spatial resolution. The results indicate that the 15 cm resolution UAV images can be used to accurately estimate forest canopy cover in 10 m cells (R2 = 0.82, RMSE = 8.9% canopy cover). Tree density estimated from individual tree segmentation outputs resulted in true positive detection of 74% of the field-mapped trees with a 16% commission error rate. The individual tree height estimates were strongly correlated to field measurements (R2 = 0.71, RMSE = 1.83 m), while canopy base height estimates had a weaker correlations with an R2 of 0.34 and RMSE of 2.52 m. Estimates of canopy bulk density showed no correlation to estimates derived from field measurements. The UAV-derived canopy cover, canopy height, and canopy base height resulted in drastically different estimates of potential crown fire behavior compared to the coarse resolution LANDFIRE dataset. In particular, estimates from LANDFIRE data showed the study area as 86% active crown fire, 14% passive crown fire, and 0% surface fire. Whereas, UAV-derived estimates showed 100% surface fire and no active or passive crown fire. These results suggest that the spatial resolution of the data can have a large impact on the estimated crown fire behavior and, therefore, on the final forest fuels reduction treatment prescription and monitoring
A taxonomic revision of Hypogena(Coleoptera: Tenebrionidae) and a review of antennal sensory structures in Tenebrionidae
Get PDFTenebrionidae is a diverse, worldwide family of beetles comprising approximately 20,000 species in 2,300 genera (Bousquet et al., 2018). Hypogena Dejean 1831 is a genus of 13 species of subcortical, horned beetles in the family. This genus is primarily identified using male specific characters like the presence of cephalic horns and aedeagal structures. Hypogena is currently placed within the tribe Triboliini, but recent phylogenetic work indicates that the current generic composition of Triboliini is paraphyletic. Scanning electron microscopy (SEM) is used to identify cryptic characters in Hypogena that separate it from other Triboliini genera. Additionally, four new species of Hypogena are described here.
Within Tenebrionidae, as with most other insects, antennae are important chemoreceptors and are putatively under a significant amount of selection pressure. In the present study, scanning electron microscopy was used to examine stellate sensoria within the family. The presence of stellate sensoria is a highly conserved trait within Tenebrionidae. Sensoria types are mapped onto a recent phylogeny of Tenebrionidae to identify patterns in sensoria evolution and classify the patterns into distinct character states. Results indicate that stellate sensoria, presence and type, are useful for delimiting higher level taxa within Tenebrionidae. Finally, this study outlines a relatively low cost method of antenna specimen preparation for examination with a scanning electron microscope. This will allow future researchers to examine stellate sensoria in other groups of Tenebrionidae to further test hypotheses presented here
The auditory sensitivity and active space of the northern grasshopper mouse (onychomys leucogaster) in relation to woody plant encroachment
No full textVocal communication is a critical component of mate choice and territoriality in many animals. The efficacy of communication depends on signal transmission through an often-cluttered environment. Anthropogenic-induced changes in vegetation structure may impact sound propagation and thus habitat quality, but few studies have explored this hypothesis. In the American Southwest, fire suppression and cattle grazing have facilitated displacement of grasslands by pinyon-juniper woodlands. Northern grasshopper mice (Onychomys leucogaster) produce long-distance vocalizations to advertise their presence to rivals and potential mates and inhabit regions impacted by juniper encroachment. Here, we coupled acoustic recordings and physiological measurements of hearing sensitivity in the laboratory with sound transmission experiments in the field to estimate the active space of grasshopper mouse calls. We found that receivers are sensitive to loud (ca. 85 dB re: 20 μPa at 1 m) 11.6 kHz calls at 30 dB and that calls travel 30 m (range: 20 – 60 m). However, we found no effect of shrub encroachment on call propagation as juniper and grass density were inversely associated and both present barriers to a 9 cm mouse advertising at ground level. Our findings suggest that juniper encroachment does not affect sound propagation but may influence habitat quality through alternative mechanisms
Sustainability of teepee pole stands on Mescalero Apache tribal lands: characteristics and climate change effects
Get PDFThe Mescalero Apache tribe conduct a coming of age ceremony for young women who follow a traditional way of life. In order to conduct this ceremony, tall, thin teepee poles made from Douglas-fir trees are needed. Douglas-fir trees capable of producing teepee poles are a culturally important resource for the Mescalero Apache tribe. We interacted with tribal members, medicine men, and tribal foresters to gain insight on characteristics of teepee pole stands. We established thirty, 0.1 acre (400 m2) circular plots with nested 0.025 acre (100 m2) regeneration plots in teepee pole producing stands to characterize composition, structure, age, growth rates, and fuels. Teepee pole producing stands occupy elevation ranges from 6,600 to 8,400 ft (2012 to 2561 m), slopes of 3%-43%, and aspects from NW to NE. The stands consist of dense, relatively old trees dominated by Douglas-fir, with other species of trees, namely white fir, southwestern white pine, ponderosa pine, Gambel oak, and juniper usually present as a minor component. Douglas-firs in teepee pole producing stands averaged 508 ± 40 trees per acre (TPA) (1255 ± 99 trees per ha (TPH)), 138.1 ± 6.5 ft2/ac basal area (31.7 ± 1.5 m2/ha), and 7.3 ± 0.2 in (18.5 ± 0.5 cm) quadratic mean diameters (QMD). Douglas-fir trees in teepee pole producing stands were most commonly 75-100 years old with diameters at breast height (DBH) ranging from 2-10 in (5.1-25.4 cm). In order to assess future trajectories of teepee pole stands, we applied the model Climate-Forest Vegetation Simulator (C-FVS) which incorporates the effects of climate change scenarios over the next 100 years. We compared three standard scenarios ranging from moderate to severe climate change, Representative Concentration Pathways (RCP) 4.5, 6.0, and 8.5. Simulated future forests at the current plot locations did not contain Douglas-fir after a century of modeling, even under the mildest climate scenario, RCP 4.5. Ninety-seven percent of plots failed to maintain a minimum basal area of 5 ft2/ac (1.1 m2/ha) of any species. Complete forest mortality was predicted under RCP 6.0 and RCP 8.5. Comparing bioclimatic niche modeling of Douglas-fir with downscaled future climate scenarios indicated that the species would have to be planted at least 1000 ft (305 m) higher to maintain 21st century viability under RCP 4.5 and 6.0, or at least 2000 ft (610 m) higher under RCP 8.0. The characterization of current teepee pole producing stands and simulations of future effects of climate change provide useful information to the Mescalero Apache Tribe to support management decisions on how they would like to preserve this cultural important resource
Episodic Sierran arc magmatism expressed in Mesozoic rocks of the Mount Morrison pendant, east-central Sierra Nevada, California
Get PDFThe Mount Morrison pendant contains approximately 40 km2 of exposed Mesozoic volcanic rocks. Triassic strata include a 1.2-km-thick intra-caldera ignimbrite; 1.5 km of dacitic rocks including a large hypabyssal sill, tuff, breccia, and sedimentary rocks; and two local deposits of subaqueous volcanic breccia. Jurassic rocks include 1.3 km of intercalated dacitic to rhyolitic tuff and breccia that are highly deformed. The Cretaceous section contains subaqueous, finely laminated sedimentary strata interlayered with rhyolite tuffs and flows, and a >400-m-thick mass of andesite porphyry. U-Pb geochronology shows that these rocks were emplaced during periods of high magmatic flux beneath the Sierran arc prior to juxtaposition by faulting. The ages of Triassic rocks range from 217 to 213 ± 2 Ma, which corresponds to the first pulse of Sierran volcanism. Rhyolite tuff in the Jurassic block was dated at 170 ± 2 Ma and thus corresponds to the second high-flux episode. Volcanic rocks of the Cretaceous block were dated at 101 ± 2 Ma, and so were sourced from the final magmatic pulse. All these volcanic rocks have geochemical signatures of arc magmas sourced from evolved crust. Structural patterns show that Triassic and Jurassic rocks underwent at least one period of deformation prior to emplacement of Cretaceous rocks, providing evidence for crustal contraction between the Middle Jurassic and latest Early Cretaceous. All rocks were deformed by the Sierra Crest shear zone during or soon after the final pulse of arc magmatism. Dextral shear indicators are consistent with Sierra Crest shear zone tectonics. The Mesozoic Mount Morrison pendant records the major stages of development of the Sierran arc as it was built on the continental crust of southwest Laurentia, offering insight into eruption style, paleogeography, and arc tempo
Integrating plant functional traits, genetics, phenotypic plasticity, and community structure to assess the impact of climate change on native plants in the southwestern U.S.
Get PDFThe southwestern U.S. is a hot spot of extreme climate change, where increasing temperatures and limited water has resulted in more frequent and severe heatwave, drought, and fire events, subsequently affecting species traits, distributions, interactions, and prevalence across the landscape. These climate extremes, combined with competition from exotic species, has resulted in the degradation of many native ecosystems, including large pine forests and riparian corridors throughout the west. In this dissertation, I examine the impact of climate change in the southwestern United States on the ecological and evolutionary processes influencing species occurrence and traits at the plant community, population, and genotype level. First, I analyze the natural climate change event of severe drought in the Northern Arizona cinderfields to understand the response of whole plant communities to the combined effects of drought-stress and overstory tree mortality. In this long-term observational study, I combine traditional taxonomic metrics with community phylogenetic measures. In the next two studies, I utilize an experimental model of climate change through the use of replicated common garden experiments, where populations of Fremont cottonwood were transplanted into environments ranging from 12°C hotter and 10°C colder compared to their origin sites. Using this design, I first explore the degree of genetic (G), environment (E), and GxE effects on two phenology traits, spring bud flush and fall bud set, within and across the three common gardens. The use of cloned genotypes allowed for the study of phenotypic plasticity for these traits, and the degree of genetic variation, and thus evolutionary potential, for plasticity. Lastly, I compared the among-population quantitative variation in phenology, growth, and leaf traits found in each common garden to their neutral genetic variation using QST-FST analysis to understand the role of climate-driven natural selection and the degree of local adaptation in shaping large phenotypic divergences across the species range. Together, these studies can help inform how important native species will respond to extreme climate events, and help shape management guidelines to ensure healthy and productive ecosystems are preserved
From water to land: Analysis of prehistoric shell from Wupatki Pueblo
Get PDFThis thesis specifically examines prehistoric shell artifacts recovered from excavations at Wupatki Pueblo, an Ancestral Puebloan site located in northern Arizona. The shell artifacts from Wupatki Pueblo were analyzed in order to accurately determine the genus and species, artifact types, and uses of shell. By looking at manufacturing techniques, this research determined if the Hohokam traded or brought shell artifacts to Wupatki Pueblo as finished products or if shell manufacturing occurred at Wupatki Pueblo. To determine the significance of shell artifacts at Wupatki Pueblo, the shell assemblage was compared to shell assemblages from Sinagua sites and Hohokam shell manufacturing sites. Ultimately, this research adds valuable information about trade, migration, and social networks between the Hohokam, Sinagua, and Ancestral Puebloans, which is important to the understandings of function, complexity, ideology, adaptation, resilience, and the foundation of modern Pueblo cultures
Intraspecific trait variation and trait-environment relationships are species specific in grasses
No full textVariation in climate has been demonstrated to be a powerful driver of selection and local adaptation among plant populations. Variation in functional traits among populations can also be indicative of the drivers of local adaptation. However, it is not clear to what extent species exhibit consistent patterns of local adaptation as revealed by common, heritable trait-environment relationships among populations. To address this, we conducted a meta-analysis of common garden studies of grass populations and a greenhouse experiment to quantify the degree of heritability of several commonly measured functional traits, and whether demonstrated heritability was driven by climate. In the meta-analysis, we found that leaf size, specific leaf area (SLA) and total biomass all displayed strong broad-sense heritability. Both leaf area and SLA decreased significantly with increasing temperature seasonality among populations within species, while total biomass increased with increasing annual and dry season precipitation, and decreased with increasing precipitation seasonality. In the greenhouse experiment, we related the measured traits to a number of environmental conditions including temperature, precipitation, vapor pressure deficit and soil moisture. We found a significant amount of variation was explained by population for both above and belowground functional traits and that individual relationships between climate and traits vary by both trait and species. Via model selection, we found that some climate variables, namely mean diurnal range and precipitation of driest quarter, are more consistently better predictors of trait outcomes. Taken together, these results indicate the importance of accounting for intraspecific trait variation, and that characterizing trait-environment relationships must be performed on species-by-species basis. Further information on trait-environment relationships within species could greatly improve our ability to predict broad scale patterns in functional diversity across multiple levels of ecological organization and benefits the fields of restoration, conservation, and global change ecology
A comparison of the situational and linguistic features of high-profile criminal trials and TV series courtroom trials
Get PDFThis dissertation provides a comprehensive description of courtroom language as a register by exploring the situational and linguistic features of authentic and TV courtroom language, as well as four public sub-registers that occur within authentic and TV courtroom (opening statement, direct examinations, cross-examinations, closing argument). It also examines how different participant roles (witnesses, attorneys) use language differently in authentic and TV courtroom trials and the four public sub-registers. Finally, it investigates the use of stance features in authentic and TV courtroom and in the four sub-registers to understand how certain stance features function within courtroom.
Studies have been conducted to provide thorough description of various types of spoken register, such as face-to-face conversations (Quaglio, 2009), TV and movie language (Bednerak, 2010), university lectures (Biber, 2009; Biber, Conrad, Reppen, Byrd, and Helt, 2002), outsourced call center phone conversations (Friginal, 2009), and nurse-patient interactions (Staples, 2015), to name just a few. Recently, there have been raising attention to the studies of courtroom language.
Courtroom language is a type of legal language, only in a spoken mode. There are some studies that investigate courtroom language which mainly focus on exploring the issues of power asymmetries that underlie dynamics of courtroom interaction (Olanrewaju, 2010), language interpretation (González, 2005), or on a particular linguistic feature such as nominal expressions (Kanté, 2010). However, most studies on courtroom language were conducted from a non-register perspective, and to date few studies have provided a comprehensive description of the linguistic characteristics (e.g., lexico-grammatical features) of courtroom language. In order to understand courtroom language as a specific register, it is important to understand its situational characteristics and linguistic features. More importantly, it is critical to identify the situational and linguistic features of the sub-registers of courtroom, as it is very likely that the situational features of the sub-registers will large influence the language used in courtroom.
An important methodological issue has been raised by this study – the need to consider sub-registers when exploring the language used in courtroom. More fine-grained level distinctions should be made when describing a register to consider situational characteristics of those sub-registers, such as communicative purpose and audience, which play a critical role in determining what linguistic features are used in that particular context. Courtroom language, although seen as a specific register of legal language, has sub-registers, with each bearing different functions. Therefore, treating courtroom language as an intact without looking into its sub-registers, differences would not be able to emerge. Only when we treat the general registers at a fine-grained level by looking into their sub-registers, shall we find the differences in language use