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Continuous monitoring of active volcanoes is essential for understanding their behavior and providing accurate forecasts and warnings. Automating the detection of volcano microseismic events plays a crucial role in large-scale analysis, early warning systems, and efficient handling of large-scale data. This paper presents a novel approach for the automated detection of microseismic events associated with volcanic activity, focusing on the Cotopaxi volcano in Ecuador. Inspired by voice activity detection (VAD) systems used in speech processing, we propose an Adaptive-Microseismic Activity Detector (A-MAD) that modifies VAD techniques to identify frames within seismic signals containing volcanic activity. The A-MAD system incorporates a spectral subtraction stage to mitigate the impact of environmental noise and employs Gaussian Mixture Models (GMMs) to model the probabilistic distribution of microseismic events. Mel Frequency Cepstral Coefficients (MFCCs) are used as features to describe the seismic signals, enabling adaptability for varying noise levels. Experimental results on signals from Cotopaxi Volcano in Ecuador demonstrate the effectiveness of the A-MAD system, achieving high accuracy (96.39% for discrete events and 98.45% for continuous signals) while meeting the efficiency requirements of volcano monitoring institutions. This work contributes to the advancement of early warning systems for volcanic eruptions, providing a robust and adaptive approach for microseismic activity detection.

This research article presents a comprehensive study focusing on advancing radar systems for unmanned aerial vehicle (UAV) surveillance in cluttered environments. The proliferation of UAV technology and its diverse applications have raised concerns about airspace security. To tackle this issue, this article introduces a novel simulator designed to evaluate the performance of primary monopulse radar processors. The simulator accurately replicates scenarios involving clutter Weibull distributions, stationary and moving targets, as well as pulse compression situations, thereby enabling precise and controlled evaluations. The study employs the simulator to assess radar processors, including a variant of moving target detection (MTD) and a constant false alarm rate (CFAR) processor. By implementing a rigorous methodology, the article underscores the significance of simulating cluttered conditions in refining the effectiveness of radar processors. The results yield valuable insights, facilitating objective interpretations. The proposed simulator and its implications contribute to enhancing UAV surveillance and airspace security, thereby pushing forward the capabilities of radar systems.

Urban forestry programs across North America rely on volunteers to lead urban forest stewardship activities and encourage participation in tree planting and general maintenance. We examined the leadership structure of a tree planting initiative (TPI) in the greater Philadelphia region to understand the role and labor contributions of volunteer leaders, and the current challenges of achieving equitable urban tree canopy within community-led TPIs. Using an online survey, we found that leaders contribute unpaid labor, time, and skills within the following categories: group organization and communication, tree-planting and event coordination, tree care and maintenance, and broader environmental education and advocacy. Volunteer leaders also face challenges related to leadership and administrative tasks. This study deepens understandings of the labor needs within volunteer TPIs and potential ways to support the equitable growth of these initiatives moving forward. Future research is needed to understand recognitional equity gaps in volunteer leadership more broadly. [ABSTRACT FROM AUTHOR]

Cities worldwide are grappling with complex urban environmental injustices. While environmental justice as a concept has gained prominence in both academia and policy, operationalizing and implementing environmental justice principles and norms remains underexplored. Notably, less attention has been given to centering the perspectives and experiences of community-based actors operating at the grassroots level, who can inform and strengthen urban environmental justice practice. Through ethnographic, participant-as-observer methods, interviews, and geovisualizations, this study explores the perspectives, experiences, knowledge, and practices of community-based urban forest stewards in Philadelphia, Pennsylvania (United States) who are invested in addressing environmental injustices through urban tree-planting and stewardship. Interviewees were asked how they were addressing issues of distribution, procedure, and recognition in urban forest planning and practice, as well as the socio-political and institutional factors that have influenced their perspectives and practices. Particular attention is given to how urban forest stewards implement recognitional justice principles. Findings from this study exposed several complex socio-political challenges affecting steward engagement in community-led tree initiatives and the broader pursuit of environmental justice, including discriminatory urban planning practices, gentrification concerns, underrepresentation of Black and Latinx voices in decision-making, volunteer-based tree-planting models, and tree life cycle costs. Nevertheless, urban forest stewards remain dedicated to collective community-building to address environmental injustices and stress the importance of recognizing, listening to, dialoguing with, and validating the perspectives and experiences of their neighbors as essential to their process. [ABSTRACT FROM AUTHOR]

With the growing ability to collect large volumes of volcano seismic data, the detection and labeling process of these records is increasingly challenging. Clearly, analyzing all available data through manual inspection is no longer a viable option. Supervised machine learning models might be considered to automatize the analysis of data acquired by in situ monitoring stations. However, the direct application of such algorithms is defiant, given the high complexity of waveforms and the scarce and often imbalanced amount of labeled data. In light of this and motivated by the wide success that generative adversarial networks (GANs) have seen at generating images, we present ESeismic-GAN, a GAN model to generate the magnitude frequency response of volcanic events. Our experiments demonstrate that ESeismic-GAN learns to generate the frequency components that characterize long-period and volcano-tectonic events from Cotopaxi volcano. We evaluate the performance of ESeismic-GAN during the training stage using Fréchet distance, and, later on, we reconstruct the signals into time-domain to be finally evaluated with Frechet inception distance.

AbstractUrban tree planting initiatives (TPIs) have become a prominent form of public work that has the potential to increase the livability and sustainability of cities. However, if not sufficiently resourced and thoughtfully planned and implemented, these high-profile programs may fail to achieve intended goals. To promote successful implementation of TPIs, we offer recommendations for the pre-planting, installation, and post-planting phases. During each of these phases we present five cross-cutting themes: ensuring adequate funding for all project phases; cultivating place-based landscape design; engaging and investing in communities; implementing sound planting practices; and evaluating performance and adapting over time. [ABSTRACT FROM AUTHOR]

Actualmente el Volcán Cotopaxi ha experimentado un incremento progresivo en su actividad sísmica, por lo que los especialistas requieren herramientas de alta eficiencia y confiabilidad para la monitorización volcánica. Este artículo presenta una detección basada en clasificación supervisada de los eventos sismo-volcánicos y no volcánicos registrados durante el año 2010. Nuestro algoritmo emplea cuatro características adquiridas por medio de la energía de los coeficientes de aproximación y detalle de la descomposición wavelet analizados con las familias Daubechies y Symlet. La clasificación de eventos fue realizada con el algoritmo de árboles de decisión empleando técnicas embebidas: validación cruzada y podamiento para una reducción del número de características. Los mejores resultados son obtenidos con la aplicación de la wavelet madre Symlet con una exactitud del 99% y una precisión de 98%.

The success of public trees planted in urban areas by tree planting initiatives (TPIs) depends on how well the new trees fit into existing municipal structures and capacities. We sought to understand municipal management of trees in mid-sized towns through a case study in Massachusetts (US) involving a state-funded and state-managed TPI. Data was collected through structured interviews with tree wardens (municipal urban forest managers) to understand the various impacts that maintenance practices, municipal support and funding, and departmental structure may have on recently planted trees. In this Massachusetts program, municipal structure influenced the number of proactive management practices as well as the size of the tree activity budget. Consideration of municipal department roles and structure by TPIs may allow for more effective implementation of these initiatives. Our study begins to fill a research gap regarding small to mid-size municipalities and their role in tree planting and maintenance. [ABSTRACT FROM AUTHOR]

While many practitioners and scholars understand the risks associated with low urban tree diversity, they often lack the ability to rectify this challenge on their own. The complex system of tree production and procurement is shaped by market pressures, nursery and site constraints, local governance, and differing professional objectives among those who grow, specify, and plant trees. To understand constraints to and opportunities for increasing urban tree diversity, we conducted a series of focus groups comprised of nursery growers, landscape architects, and municipal tree managers. Our results highlight a significant list of considerations and constraints to diversity, with some issues shared among green industries and some specific to growers or purchasers. In light of our findings, we outline actionable strategies for increasing urban tree diversity. [ABSTRACT FROM AUTHOR]

Green infrastructure (GI) refers to trees, rain gardens, rain barrels, and other features that address stormwater management, climate change and other challenges facing many cities. GI is often not equitably distributed across urban landscapes, making its benefits unevenly experienced. Cities have multiple initiatives focused on different types of GI in residential areas, including underserved neighborhoods, although there is potential for GI programs to serve more privileged neighborhoods. The goal of this study was to examine GI program participants and non-participants to better understand who participates in different types of residential GI programs and why. We surveyed residents who had previously participated in Philadelphia's GI programs as well as those who had not, comparing socio-demographics, knowledge-levels, environmental concerns, outdoor space preferences, motivations and barriers. We found that the GI program participants are on average younger, wealthier, more highly educated, and more likely to be White than our sample of residents who have not participated. Participants in tree programs have different socio-demographics and motivations as compared to those who installed green stormwater infrastructure. Future research should examine strategies to reach neighborhoods with different socioeconomic conditions and built environment characteristics, such as offering features appropriate for small properties with limited plantable space. [ABSTRACT FROM AUTHOR]

Many women and women-run associations were involved in historical urban beautification in the United States, especially tree planting, in the late 19th and early 20th centuries. While men had formal roles as city foresters, arborists, horticulturalists, and landscape architects, women from elite families sometimes labored for free to organize and advocate for urban tree planting. Tightly knit social circles of high-society women in Philadelphia, Pennsylvania, yielded much greater influence in nascent tree planting and park creation movements than has generally been recognized. They often contributed their time, finances, input, and skill to landscape planting projects; however, they were not considered equal to the men who were compensated employees. These women planted, plotted, studied, and persevered, overcoming preconceived notions of womanhood, although their meaningful efforts were often viewed as merely an offshoot of their feminine domestic role. For women, limited by opportunities in male-dominated arenas, shaping their cities was a socially accepted means for empowerment. Ellen Waln Harrison (1846 to 1922) was a key figure in civic beautification in her hometown of Philadelphia and beyond. Ellen Harrison was married to Charles Custis Harrison, Provost of the University of Pennsylvania, and she personally oversaw campus landscaping efforts, and was referred to as his "right hand." Her story is emblematic of a larger trend regarding women in botany, horticulture, and urban forestry around the turn of the 20th century. [ABSTRACT FROM AUTHOR]

Urban trees in lawns and along streets are anthropogenically constructed systems, in that these tree communities are formed by human planting and removal actions. Tree mortality studies are essential to understanding the temporal dynamism of urban forests, and in particular, it is critical to incorporate institutional records and human decision-making regarding tree removals. In this study, we investigated tree removals on a highly urbanized college campus in Philadelphia, Pennsylvania (US) by analyzing field inventories and institutional records, and by considering firsthand accounts of the University Landscape Architect. The annual mortality rate was 4.3%, higher than typical for comparable studies, which we attribute to construction pressure and proactive management to promptly remove unhealthy trees and manage risk. Capital projects and other construction caused 48.5% of all removals, other human land use decisions caused 2.0%, and tree health decline and risk management collectively accounted for 48.7%. The number of removed trees exactly equaled the number of new trees, and the campus has high taxonomic diversity, reflecting the extensive oversight by university tree and landscape professionals regarding tree removal and planting decisions. This study demonstrates the value of mixed-methods and transdisciplinary research to understand how urban forests change over time. [ABSTRACT FROM AUTHOR]