Filtering by
- Creators: Arizona State University
- Status: Published
![161500-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-11/161500-Thumbnail%20Image.png?versionId=j1Z1G1P8fIxi6ke8n9m0PxjUe0DkrFfs&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T201301Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=69386a9cfb77f4414184025ed65d70f0970920f4a3719c87549596f8c0e5b37b&itok=eh4-Z4WN)
![161513-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-11/161513-Thumbnail%20Image.png?versionId=vWQb4PGK7D1BtT_F_NozYNXnaS9iH9YI&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T165308Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=68d12096d459a3d79329233dede41552ffc04a467a473cb13b259ac9219d0326&itok=xmaM95bi)
![161882-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-11/161882-Thumbnail%20Image.png?versionId=rASHY_SlkTEcgYLnk4VYjQgvH5zMxS7t&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T201301Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=93b5b5d209154fa6c2a45eb962a6769f007b21209eeedc5784653da587894f0f&itok=ypBQfBkk)
![161918-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-11/161918-Thumbnail%20Image.png?versionId=FY9phk4D5grDsLJfEaZuMaaViTlF9s4h&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T183948Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=38649e8c8ca5d8b481c99a254b985f0b1bb8fe9cc4b429c1511f2f836d958533&itok=q5Xm7nGt)
Assessing the Response of Macroinvertebrate Communities to River Flow Dynamics in the Sonoran Desert
Climate change is causing hydrologic intensification globally by increasing both the frequency and magnitude of floods and droughts. While environmental variation is a key regulator at all levels of ecological organization, such changes to the hydrological cycle that are beyond the normal range of variability can have strong impacts on stream and riparian ecosystems within sensitive landscapes, such as the American Southwest. The main objective of this study was to investigate how anomalous hydrologic variability influences macroinvertebrate communities in desert streams. I studied seasonal changes in aquatic macroinvertebrate abundances in eleven streams that encompass a hydrologic gradient across Arizona’s Sonoran Desert. This analysis was coupled with the quantification and assessment of stochastic hydrology to determine influences of flow regimes and discrete events on invertebrate community composition. I found high community variability within sites, illustrated by seasonal measures of beta diversity and nonmetric multidimensional scaling (NMDS) plots. I observed notable patterns of NMDS data points when invertebrate abundances were summarized by summer versus winter surveys. These results suggest that there is a difference within the communities between summer and winter seasons, irrespective of differences in site hydroclimate. Estimates of beta diversity were the best metric for summarizing and comparing diversity among sites, compared to richness difference and replacement. Seasonal measures of beta diversity either increased, decreased, or stayed constant across the study period, further demonstrating the high variation within and among study sites. Regime shifts, summarized by regime shift frequency (RSF) and mean net annual anomaly (NAA), and anomalous events, summarized by the power of blue noise (Maximum Blue Noise), were the best predictors of macroinvertebrate diversity, and thus should be more widely applied to ecological data. These results suggest that future studies of community composition in freshwater systems should focus on understanding the cause of variation in biodiversity gradients. This study highlights the importance of considering both flow regimes and discrete anomalous events when studying spatial and temporal variation in stream communities.
![127834-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-04/127834-Thumbnail%20Image.png?versionId=l0pb2bY8atSRYMgs24OcWyOErMkd6hTq&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240618/us-west-2/s3/aws4_request&X-Amz-Date=20240618T090614Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=7575e9088ae7c0a6dd09c911361bcaf7aba3357dc07aa02669975941049504a6&itok=pcAzcBkV)
Communicating climate risks is crucial when engaging the public to support climate action planning and addressing climate justice. How does evidence-based communication influence local residents’ risk perception and potential behavior change in support of climate planning? Built upon our previous study of Climate Justice maps illustrating high scores of both social and ecological vulnerability in Michigan’s Huron River watershed, USA, a quasi-experiment was conducted to examine the effects of Climate Justice mapping intervention on residents’ perceptions and preparedness for climate change associated hazards in Michigan. Two groups were compared: residents in Climate Justice areas with high social and ecological vulnerability scores in the watershed (n=76) and residents in comparison areas in Michigan (n=69). Measurements for risk perception include perceived exposure, sensitivity, and adaptability to hazards. Results indicate that risk information has a significant effect on perceived sensitivity and level of preparedness for future climate extremes among participants living in Climate Justice areas. Findings highlight the value of integrating scientific risk assessment information in risk communication to align calculated and perceived risks. This study suggests effective risk communication can influence local support of climate action plans and implementation of strategies that address climate justice and achieve social sustainability in local communities.
![154286-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-08/154286-Thumbnail%20Image.png?versionId=vHZLmSTjacVmeC.kxyqnA1t34u9FIE0Q&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T183821Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=5fc13e5cfcc36423360725bbecee88c0d4f20b8dc9667a53976130f139cab593&itok=Ha3BPIRf)
Using the individual building energy simulation approach, I also estimate the impact of climate change to different building types at over 900 US locations. Large increases in building energy consumption are found in the summer, especially during the daytime (e.g., >100% increase for warehouses, 5-6 pm). Large variation of impact is also found within climate zones, suggesting a potential bias when estimating climate-zone scale changes with a small number of representative locations.
As a result of climate change, the building energy expenditures increase in some states (as much as $3 billion/year) while in others, costs decline (as much as $1.4 billion/year). Integrated across the contiguous US, these variations result in a net savings of roughly $4.7 billion/year. However, this must be weighed against the cost (exceeding $19 billion) of adding electricity generation capacity in order to maintain the electricity grid’s reliability in summer.
![154788-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2021-09/154788-Thumbnail%20Image.png?versionId=pKlfrTYKgGIJSthM3c9oIyBP_yYWEqBR&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T185754Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=d611194a50aad5e982475c93bf6c7100d4dfac76f4f730f84697ec8ce51197b6&itok=OiY00BHb)
This dissertation includes two main parts. The first part proposes to employ the continuous, pixel-based landscape gradient models in comparison to the discrete, patch-based mosaic models and evaluates model efficiency in two empirical contexts: urban landscape pattern mapping and land cover dynamics monitoring. The second part formalizes a novel statistical model called spatially filtered ridge regression (SFRR) that ensures accurate and stable statistical estimation despite the existence of multicollinearity and the inherent spatial effect.
Results highlight the strong potential of local indicators of spatial dependence in landscape pattern mapping across various geographical scales. This is based on evidence from a sequence of exploratory comparative analyses and a time series study of land cover dynamics over Phoenix, AZ. The newly proposed SFRR method is capable of producing reliable estimates when analyzing statistical relationships involving geographic data and highly correlated predictor variables. An empirical application of the SFRR over Phoenix suggests that urban cooling can be achieved not only by altering the land cover abundance, but also by optimizing the spatial arrangements of urban land cover features. Considering the limited water supply, rapid urban expansion, and the continuously warming climate, judicious design and planning of urban land cover features is of increasing importance for conserving resources and enhancing quality of life.
![190809-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2023-12/190809-Thumbnail%20Image.png?versionId=AxRzIsv5qQ7cS7oFDqedMfUOeM4hQ_Vq&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T190311Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=7615f7b33fe548b4aac34a990499755194a5810ed75b7e68d993f9b989489869&itok=wc0tRkpQ)
![194167-Thumbnail Image.png](https://d1rbsgppyrdqq4.cloudfront.net/s3fs-public/styles/width_400/public/2024-06/194167-Thumbnail%20Image.png?versionId=CV0oLt5diQAWG5V.CSADv5LxsxO8rZ.C&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIASBVQ3ZQ42ZLA5CUJ/20240619/us-west-2/s3/aws4_request&X-Amz-Date=20240619T174939Z&X-Amz-SignedHeaders=host&X-Amz-Expires=120&X-Amz-Signature=5ebd5cdf67840f55cd0eba6500759509b363001990b295b18a506e822e0e0f7d&itok=ivpfpgq2)