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Evolving Earth observation and change detection techniques enable the automatic identification of Land Use and Land Cover Change (LULCC) over a large extent from massive amounts of remote sensing data. It at the same time poses a major challenge in effective organization, representation and modeling of such information. This study proposes and implements an integrated computational framework to support the modeling, semantic and spatial reasoning of change information with regard to space, time and topology. We first proposed a conceptual model to formally represent the spatiotemporal variation of change data, which is essential knowledge to support various environmental and social studies, such as deforestation and urbanization studies. Then, a spatial ontology was created to encode these semantic spatiotemporal data in a machine-understandable format. Based on the knowledge defined in the ontology and related reasoning rules, a semantic platform was developed to support the semantic query and change trajectory reasoning of areas with LULCC. This semantic platform is innovative, as it integrates semantic and spatial reasoning into a coherent computational and operational software framework to support automated semantic analysis of time series data that can go beyond LULC datasets. In addition, this system scales well as the amount of data increases, validated by a number of experimental results. This work contributes significantly to both the geospatial Semantic Web and GIScience communities in terms of the establishment of the (web-based) semantic platform for collaborative question answering and decision-making.
ContributorsVadjunec, Jacqueline M. (Author) / Radel, Claudia (Author) / Turner II, B. L. (Author) / College of Liberal Arts and Sciences (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor)
Created2016-10-25
Description
The growth rate hypothesis (GRH) proposes that higher growth rate (the rate of change in biomass per unit biomass, μ) is associated with higher P concentration and lower C∶P and N∶P ratios. However, the applicability of the GRH to vascular plants is not well-studied and few studies have been done on belowground biomass. Here we showed that, for aboveground, belowground and total biomass of three study species, μ was positively correlated with N∶C under N limitation and positively correlated with P∶C under P limitation. However, the N∶P ratio was a unimodal function of μ, increasing for small values of μ, reaching a maximum, and then decreasing. The range of variations in μ was positively correlated with variation in C∶N∶P stoichiometry. Furthermore, μ and C∶N∶P ranges for aboveground biomass were negatively correlated with those for belowground. Our results confirm the well-known association of growth rate with tissue concentration of the limiting nutrient and provide empirical support for recent theoretical formulations.
ContributorsYu, Qiang (Author) / Wu, Honghui (Author) / He, Nianpeng (Author) / Lu, Xiaotao (Author) / Wang, Zhiping (Author) / Elser, James (Author) / Wu, Jianguo (Author) / Han, Xingguo (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor)
Created2012-03-13
Grasshoppers Regulate N: P Stoichiometric Homeostasis by Changing Phosphorus Contents in Their Frass
Description
Nitrogen (N) and phosphorus (P) are important limiting nutrients for plant production and consumer performance in a variety of ecosystems. As a result, the N:P stoichiometry of herbivores has received increased attention in ecology. However, the mechanisms by which herbivores maintain N:P stoichiometric homeostasis are poorly understood. Here, using a field manipulation experiment we show that the grasshopper Oedaleus asiaticus maintains strong N:P stoichiometric homeostasis regardless of whether grasshoppers were reared at low or high density. Grasshoppers maintained homeostasis by increasing P excretion when eating plants with higher P contents. However, while grasshoppers also maintained constant body N contents, we found no changes in N excretion in response to changing plant N content over the range measured. These results suggest that O. asiaticus maintains P homeostasis primarily by changing P absorption and excretion rates, but that other mechanisms may be more important for regulating N homeostasis. Our findings improve our understanding of consumer-driven P recycling and may help in understanding the factors affecting plant-herbivore interactions and ecosystem processes in grasslands.
ContributorsZhang, Zijia (Author) / Elser, James (Author) / Cease, Arianne (Author) / Zhang, Ximei (Author) / Yu, Qiang (Author) / Han, Xingguo (Author) / Zhang, Guangming (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor)
Created2014-08-04
Description
The purpose of this project was to create a workshop for adults without dance experience to immerse them in dance as a form of therapy. The goals of this workshop are to foster physical awareness and physical creativity. There are four main areas the participants would get experience in from this workshop including self-care/awareness, expression, gesture and choreography. These four areas are the ways that the two main goals manifest themselves. For this project I reviewed research by many different professionals from the therapy, psychology, self-care, dance, and dance therapy fields. Their studies as well as my own experience aided in putting together my themes for the workshop and class activities. I include my methodology, lesson plans, a workbook, and my reflection on the process.
ContributorsWilson, Deepika (Author) / Roses-Thema, Cynthia (Thesis director) / Giorgis, Cyndi (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
A large fraction of the world grasslands and savannas are undergoing a rapid shift from herbaceous to woody-plant dominance. This land-cover change is expected to lead to a loss in livestock production (LP), but the impacts of woody-plant encroachment on this crucial ecosystem service have not been assessed. We evaluate how tree cover (TC) has affected LP at large spatial scales in rangelands of contrasting social–economic characteristics in the United States and Argentina. Our models indicate that in areas of high productivity, a 1% increase in TC results in a reduction in LP ranging from 0.6 to 1.6 reproductive cows (Rc) per km[superscript 2]. Mean LP in the United States is 27 Rc per km[superscript 2], so a 1% increase in TC results in a 2.5% decrease in mean LP. This effect is large considering that woody-plant cover has been described as increasing at 0.5% to 2% per y. On the contrary, in areas of low productivity, increased TC had a positive effect on LP. Our results also show that ecological factors account for a larger fraction of LP variability in Argentinean than in US rangelands. Differences in the relative importance of ecological versus nonecological drivers of LP in Argentina and the United States suggest that the valuation of ecosystem services between these two rangelands might be different. Current management strategies in Argentina are likely designed to maximize LP for various reasons we are unable to explore in this effort, whereas land managers in the United States may be optimizing multiple ecosystem services, including conservation or recreation, alongside LP.
ContributorsAnadon, Jose Daniel (Author) / Sala, Osvaldo (Author) / Turner II, B. L. (Author) / Bennett, Elena M. (Author) / College of Liberal Arts and Sciences (Contributor) / School of Life Sciences (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)
Created2014-09-02
Description
We studied the microbial community structure of pilot two-stage membrane biofilm reactors (MBfRs) designed to reduce nitrate (NO[subscript 3]–) and perchlorate (ClO[subscript 4]–) in contaminated groundwater. The groundwater also contained oxygen (O[subscript 2]) and sulfate (SO[2 over 4]–), which became important electron sinks that affected the NO[subscript 3]– and ClO[subscript 4]– removal rates. Using pyrosequencing, we elucidated how important phylotypes of each “primary” microbial group, i.e., denitrifying bacteria (DB), perchlorate-reducing bacteria (PRB), and sulfate-reducing bacteria (SRB), responded to changes in electron-acceptor loading. UniFrac, principal coordinate analysis (PCoA), and diversity analyses documented that the microbial community of biofilms sampled when the MBfRs had a high acceptor loading were phylogenetically distant from and less diverse than the microbial community of biofilm samples with lower acceptor loadings. Diminished acceptor loading led to SO[2 over 4]– reduction in the lag MBfR, which allowed Desulfovibrionales (an SRB) and Thiothrichales (sulfur-oxidizers) to thrive through S cycling. As a result of this cooperative relationship, they competed effectively with DB/PRB phylotypes such as Xanthomonadales and Rhodobacterales. Thus, pyrosequencing illustrated that while DB, PRB, and SRB responded predictably to changes in acceptor loading, a decrease in total acceptor loading led to important shifts within the “primary” groups, the onset of other members (e.g., Thiothrichales), and overall greater diversity.
ContributorsOntiveros-Valencia, Aura (Author) / Tang, Youneng (Author) / Zhao, Heping (Author) / Friese, David (Author) / Overstreet, Ryan (Author) / Smith, Jennifer (Author) / Evans, Patrick (Author) / Rittmann, Bruce (Author) / Krajmalnik-Brown, Rosa (Author) / Biodesign Institute (Contributor) / Swette Center for Environmental Biotechnology (Contributor) / Julie Ann Wrigley Global Institute of Sustainability (Contributor) / School of Sustainability (Contributor)
Created2014-07-01
Description
The United Nations outlined seventeen goals in their 2015 resolution aimed at securing a more sustainable future for the entire world. These goals cover all parts of life and are meant to standardize quality of life at a high level for all countries. Specific to the Maasai people of Kenya and Tanzania, there are five main goals that would tackle some of the biggest issues facing the Maasai and greatly improve their lives. These goals include the promotion of good health and well-being, ensuring a quality education for school-age children, supporting efforts for gender equality in all communities, and securing clean and safe water and sanitation services for all people around the world. There are many Non-Governmental Organizations (NGOs) in the Maasai community that are striving to support them and realize these Sustainable Development Goals. Organizations like the Maasai Girls Education Fund and Aid Tanzania have established educational programs to support children, mainly girls, in their efforts to get an education. Others like End Water Poverty and the Maasai Association have programs to ensure safe, accessible drinking water is made available to Maasai communities across Kenya and Tanzania. Lastly, NGOs like My Chosen Vessels have programs that support the economic sustainability and livestock management of the Maasai while also ensuring that Maasai families receive clean water and access to an education. The work and practices of NGOs like these can serve as examples of how to efficiently and effectively address and tackle issues in developing countries, specifically regarding Maasai women and girls, to move closer to achieving these UN Sustainable Development Goals and lead a more sustainable future. Many studies have been done researching the political and economic struggles for Maasai communities and how it impacts them. Vandana Shiva coined the term, “Water Democracy” in her book Water Wars to express the multiple reasons why water is a necessity and right. Many Maasai groups do not have easy access to basic essentials for their everyday lives and NGOs have been noticing this more and more. Dorothy Hodgson writes about the history of Maasai NGOs, and mentions the multiple conflicts that they have had with each other, causing many Maasai groups to have different lifestyles. The connections between the history of the Maasai tribe, their current economy and their current relationship with the government and NGOs all impact women in their communities in different ways.
ContributorsWacloff, Jianna K (Author) / Martin, Thomas (Thesis director) / Oberle, Eric (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This policy proposal paper is designed to address concerns about the protection of data
concerning citizens of the United States. The first step is to explore the need for federal
legislation because of the problems of cyberattacks, data loss and leakage, and big data. The
proposal then analyses how other countries had already addressed these concerns for their
citizens through legislation by looking at their regulation and the results of implementation. The
paper adjacently discusses the importance of American values of privacy as a fundamental right,
the free market, and protection from the private sector within a cybersecurity paradigm. From
this combined research, the paper yields a proposal of how the U.S. government should address
the situation through federal policy. The policy outlines cybersecurity measures to protect
information from cyberattacks and data loss and leakage, rights of American citizens that
organizations need to uphold, and the creation of a commission that provides resources and
education to domestic and foreign organizations.
concerning citizens of the United States. The first step is to explore the need for federal
legislation because of the problems of cyberattacks, data loss and leakage, and big data. The
proposal then analyses how other countries had already addressed these concerns for their
citizens through legislation by looking at their regulation and the results of implementation. The
paper adjacently discusses the importance of American values of privacy as a fundamental right,
the free market, and protection from the private sector within a cybersecurity paradigm. From
this combined research, the paper yields a proposal of how the U.S. government should address
the situation through federal policy. The policy outlines cybersecurity measures to protect
information from cyberattacks and data loss and leakage, rights of American citizens that
organizations need to uphold, and the creation of a commission that provides resources and
education to domestic and foreign organizations.
ContributorsBrockman, Emily M. (Author) / Hollinger, Keith (Thesis director) / Walsh, Tatiana (Committee member) / Martin, Thomas (Committee member) / College of Integrative Sciences and Arts (Contributor) / Information Technology (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
In most bird species, females disperse prior to their first breeding attempt, while males remain close to the place they were hatched for their entire lives (Greenwood and Harvey (1982)). Explanations for such female bias in natal dispersal have focused on the potential benefits that males derive from knowing the local environment to establish territories, while females search for suitable mates (Greenwood (1980)). However, the variables shaping dispersal decisions appear more complex (Mabry et al. (2013), Végvári et al. (2018)). There are a number of different variables that could act as a driving force behind dispersal including the social mating system, food competition, inbreeding avoidance, predation, and others. Here, we investigate whether females are the dispersing sex in great-tailed grackles, which have a mating system where the males hold territories and the females choose which territory to place their nest in (Johnson et al. (2000)). We used genetic approaches to identify sex biases in the propensity to disperse. In the experiment, we found that the male grackles were less related to each other while the female grackles were more related to each other. Building on that, the average distance between closely related individuals of the male group was longer than the average distance of closely related females. But, the mantel correlograms for the males and females both lack a consistent trend. Overall, the results indicated suggest that the males are the dispersing sex while the females are potentially philopatric and that the average dispersal distance for the grackle is greater than 2000 meters, the size of the sampling range used in the experiment. These results will inform our long-term study on the relationship between behavioral flexibility and rapid geographic range expansion by elucidating which individuals are likely to experience similar conditions across their lives, and which are likely to face new conditions when they become breeders.
ContributorsSevchik, August L (Author) / Langergraber, Kevin (Thesis director) / Logan, Corina (Committee member) / College of Integrative Sciences and Arts (Contributor) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
In this paper, I describe the development of a unique approach to developing strategies for games in which success can only be measured by the final outcome of the game, preventing the use of heuristics. I created and evaluated evolutionary algorithms, applying them to develop strategies for tic-tac-toe. Strategies are comprised of neural networks with randomly initiated weights. A population of candidate strategies are created, each strategy competes individually against each other strategy, and evolutionary operators are applied to create subsequent generations of strategies. The set of strategies within a generation of the evolutionary algorithm forms a metagame that evolves as the algorithm progresses. Hypothesis testing shows that strategies produced by this approach significantly outperform a baseline of entirely random action, although they are still far from optimal gameplay.
ContributorsRodriguez, Julien Guillermo (Author) / Martin, Thomas (Thesis director) / Powers, Brian (Committee member) / College of Integrative Sciences and Arts (Contributor, Contributor) / Department of Information Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05