Riparian zones are interfaces between freshwater and terrestrial ecosystems. These zones provide several ecosystem services and support an immense amount of biodiversity. Riparian zones cover about 1% of southwestern North American landscape, yet the riparian zones contain an abundance of richness and wildlife. In western North America, most of these ecosystems have been degraded or altered. Efforts to restore these riparian ecosystems continue to grow and in urban settings watercourses are diverted from floodplains to protect urban infrastructure.

In this study they assess the responses of wildlife to habitat restoration and floodplain management efforts. The study site is located in Tucson, Arizona. Specifically, they assess communities of diurnal lizards and how they are affected by Pima County Regional Flood Control District efforts to flood control. Included in these efforts RFCD enhance habitats through vegetation seeding and planting, and water retention. The researched the lizards before and after the treatment in a nearby tributary and a major river course.

It was found that restoration efforts mitigated the impacts of flood control management and provided benefits for some species. A tradeoff was identified in the data as there were negative impacts identified in at least one species of lizard. Terrestrial species with faster maturity times recovered faster than arboreal species with longer maturity times. Also the data suggests that management efforts should be paired with restoration efforts to maximize human and wildlife benefits.

I honestly do not feel that the study could improve. I found zero areas to negatively critique. The researchers conducted this study over several years, they provided a control experiment testing the area before undergoing restoration and compared that to the data they collected after the restoration and management efforts. They also went into distinct detail on both trait-dependent variation responses and context-dependent variation responses using the hard data collected throughout the experiment. This experiment is solely based on the effects against diurnal lizards, but I feel this is great framework to conduct in several other species to compare if management and restoration efforts are positive and neutral to other species affected in the area.

Wyman, Jules T., et al. “Long-Term Impacts of Urban Floodplain Management and Habitat Restoration on Lizard Communities in a Sonoran Desert City.” Ecological Engineering, vol. 197, Dec. 2023, doi:https://doi.org/10.1016/j.ecoleng.2023.107121.

The human population in urban areas will increase by 2.7 billion from 2010 to 2050. Vertebrates such as amphibians are under threat, about 40% of amphibian species are threatened with extinction. Urban development affects around 950 amphibian species with extinction. This paper stresses the concerns about how amphibians are some of the least studied vertebrate groups in urbanized landscapes, and how most land management is derived from studies of a few common species mostly leaving out amphibians and in turn failing to cater to all affected species leading to a higher risk of decline.

The researchers studied the distribution of pond-breeding frogs during breeding season in an area consisting of rural, forests, and urban areas. The site was focused in southeastern Australia, specifically it was conducted between Nowra and Booderee National Park.

The area is mostly dominant with native eucalypt forests and wetlands, consisting of both urban and rural areas. The researchers surveyed a total of 28 ponds within the study area boundaries. Frog calls were recorded at ponds during breeding season as this is when peak calling activity occurs. The researchers did state that two sites were not surveyed in urban areas due to vandalism and access, which I thought interesting as this could skew the data, especially since we are specifically looking at urbanization effects.

Aquatic and terrestrial variables were measured, variables such as water body size, and cover of surface vegetation. For this study they also took into account an exotic fish species, the eastern gambusia, because of its negative impact on frog populations. Personally, I feel this is an important factor to consider when studying specific species. This framework could be implemented when studying other species, it would obviously vary based on location. I believe the measurement of the exotic fish factor to be short. The researchers performed one five-minute visual search and placed a trap in the pond for three days. I don’t believe that to be maximizing efficiency on that specific factor, but data was captured, nonetheless.

It was found that some frog species had a positive association to urbanization while others had a negative association. It is known that the number of roads has a negative correlation to frog species richness. The paper suggests biodiversity metrics such as total species richness may underestimate urbanization impacts. It is still suggested that urbanization is a key driver in loss of pond-breeding frogs in the study region. Only one breeding season was examined in this study, yet the researchers expect the patterns of occurrence to be common to what was quantified and reflected in this study. Ultimately it was concluded that uncommon frog species are more sensitive to terrestrial modification where common frogs respond more to local aquatic variables.

I felt this paper was great at identifying the environmental variables that correlated to uncommon and common frogs. I did feel the paper lacked the measurement of environmental conditions. An example would be humidity and soil moisture. I feel the study could have been constructed in the manner of grouping the different study sites based on these factors rather than consolidating them to a basic body of water label. Also, the sites were based on urban, rural, and forested areas, the lack of knowledge on the history of the urban study sites I feel affected the data presented. The reader does not know if the urban areas are settled, or newly constructed. I feel knowing if the frogs have adapted to the changed environment or are adapting is crucial to scaling the impact of urbanization.

Villasenor, Nelida R., and Don A. Driscoll. “The Relative Importance of Aquatic and Terrestrial Variables for Frogs in an Urbanizing Landscape: Key Insights for Sustainable Urban Development.” Landscape and Urban Planning, vol. 157, Jan. 2017, p. 26–35, doi:https://doi.org/10.1016/j.landurbplan.2016.06.006.

Urban metabolism can be defined as the sum of the technical and socio-economic processes that occur in cities, resulting in growth, production of energy, and elimination of waste. This classification of urban environments encompasses quantifying outputs, inputs and storage of energy, nutrients, water, materials and wastes for an urban region. Although this article was written years ago, quantifying data varies temporally. I wanted to express my confusion about why the research varies. It was expressed that studies were made in the 1970s and interest dropped off in the 1980s. No further information was provided on the matter, so as the reader I am left with the question of why this happened. I am sure a further study could be conducted; my immediate thoughts were political conflicts or lack of funding as more research broke out in the 1990s.

When defining the urban metabolism factoring scale is of major concern. When factoring in such a matter, the author describes the review of two separate methodical approaches to the idea of urban metabolism. The two approaches being energy equivalence and the flow of resources. In particular, solar energy was the universal metric in the study as recognition of the variation in the quality of different forms of energy were made, while the mainstream of study being the flow of resources because it was more readily accessible and easily understandable when communicating with local government officials.

Research references across the globe were provided about urban metabolism. Some places including Hong Kong, London, Toronto, Phoenix, UK, Lisbon, Ireland, and BangKok. The author primarily focuses on a single application for urban metabolism, although still provides research on every application in which it was used. I felt that was an important thing to note as most articles would cut out the unnecessary information, but the reader can get ideas on other applications in this article. The author reviews the application in terms of all things encompassing sustainability. The terms include urban greenhouse gas accounting, urban design, sustainability reporting, and mathematical modeling for policy analysis. These are just the practical applications for urban planners.

There are four major urban activities: to reside and work, to clean, to transport and communicate, and to nourish and recover. There are four major components to urban metabolism: energy, food, water, and construction materials. These features can be taken into account when reconstructing cities. An example of this would be New Orleans after hurricane Katrina. This framework of thinking is being implemented within the industrial ecology community, which now focuses on urban and social metabolism. The author provides a list of several advantages of the application of urban metabolism framework. Some which include, accounts for inputs and outputs to the system, integrates social science and biophysical science/technology, and necessitates analysis of policy and technology outcomes with respect to sustainability goals.

This paper did a wonderful job at reviewing research on urban metabolism as a whole. The author referenced over 50 papers in total all pertaining to research on urban metabolism in different years. The author also starts off in the first couple paragraphs providing the reader with questions to ponder while learning about urban metabolisms research history. The author leads out with the idea that further work needs to be done and explains that an important future direction that needs to take place is more implementation to economic, social, and health indicators into the framework of the research. I could not agree more with that statement. When understanding the research that has been done these factors were lacking when understanding the urban metabolism as a whole.

Kennedy, C., et al. “The Study of Urban Metabolism and Its Applications to Urban Planning and Design.” Environmental Pollution, vol. 167, no. 8-9, Aug. 2012, p. 184–185, doi:https://doi.org/10.1016/j.envpol.2010.10.022.