A Case Study of Form-Based Solutions for Watershed Protection

Despite an array of policies at the federal and state level aimed at regulating stormwater discharges, engineered solutions enforced by local governments often fall short of meeting water quality standards. Although the implications of land use planning and development regulations are important for stormwater management, they are often overlooked as critical initial steps to improving water quality. This study explores the role of ‘form-based’ regulations as tools for achieving urban planning and water quality objectives. Form-based codes are a new generation of development codes aimed at regulating urban development based on urban form and density, rather than land use. We present an exploratory case study of the feasibility of form-based codes in the Jordan Lake Watershed in North Carolina, a rapidly growing region where fragmented local governments face stringent nutrient reduction standards under new state regulations. Through program analysis and interviews, we explore the viability of form-based codes for reducing development impacts on Jordan Lake’s water quality. We consider the legal feasibility of code enforcement, regional and local barriers and opportunities, and implementation given existing regulatory frameworks. Our findings suggest that high quality information and data modeling are foundational to gaining support for a consensus agreement on the sources and degree of water quality impairment. Furthermore, implementing form-based solutions for water quality is greatly aided by (1) experienced regional planning bodies that have regulatory authority, and (2) local governments whose staff are experienced in implementing complex development ordinances, reviewing architectural renderings, and communicating development requirements with the public and developers.     

Ranch Ownership Change and New Approaches to Water Resource Management in Southwestern Montana: Implications for Fisheries1

Abstract:  This article reports on a survey of ranch owners in high amenity areas in southwestern Montana that have experienced marked ownership change over the last two decades. Specifically, we focus on findings from a set of questions targeting water resource and riparian area management. After reviewing the results, we consider how new owners may be managing water resources differently than longtime owners and what the ecological implications of this shift in management might be for Montana’s prized wild fisheries. Uses more closely associated with new owners than with longtime owners include water reallocation to instream uses, aquatic and riparian ecosystem restoration, and fish pond construction. These uses have both positive and negative impacts on the region’s fisheries. Our findings suggest that current laws and institutions guiding the management of water resources and the aquatic and riparian ecosystems they support may not be adequate to address emerging conservation opportunities and challenges.     

PREDICTING IMPACTS FROM WATER CONSERVATION AND ENERGY DEVELOPMENT ON THE SALTON SEA,CALIFORNIA1

ABSTRACT: An input-output model was developed to predict changes in Salton Sea salinity and water level until the year 2000 due to proposed water conservation efforts and geothermal and solar pond energy developments. The model SALINP provided good agreement with the observed salinities for 1960–80. While SALINP was not overly sensitive to one-year changes in any of the major inputs, a change in the historical means of the Imperial Valley runoff and evaporative loss inputs produced a significant effect on future predictions. The proposed water conservation measures caused the predicted Salton Sea salinity for 2000 to greatly exceed 40,000 ppm, the level at which adverse effects to wildlife are believed to occur. The possible geothermal development also produced predicted salinities considerably above 40,000 ppm. The salinity predictions for solar ponds by themselves and in conjunction with geothermal development were below 45,000 ppm for 2000. The solar pond and geothermal combination also resulted in a predicted lowering of the “natural” water level by 5 to 7 feet by 2000.     

Deconstructing sustainable rubber production: contesting narratives in rural Sumatra

ABSTRACT

The growing demand for natural rubber is increasingly threatening biodiversity and forest ecosystems. Recently, the French Michelin Group started a cooperation with the World Wide Fund for Nature (WWF) to establish environmentally and socially sustainable ‘model’ rubber plantations in Sumatra and Kalimantan, Indonesia. The framing of Michelin’s tyre production as ‘eco-friendly’ and their purported ‘sustainable’ rubber cultivation contradict with statements by villagers living around Michelin’s plantation in Jambi Province, Sumatra, who are reporting environmental destruction and land tenure conflicts. Conceptually, we build on political ecology and critical human geography perspectives to identify conflicts and ambiguities related to sustainability claims, deforestation and dispossession. Empirically, we draw on qualitative research in a village affected by the plantation. We confront and deconstruct the discursive framing of sustainable rubber production with our empirical findings. We show how the plantation restricts access to land and instead of providing additional income, is actually limiting development opportunities.     

Persistence of Viruses by qPCR Downstream of Three Effluent-Dominated Rivers in the Western United States

This study was designed to determine the quantitative polymerase chain reaction (qPCR) signal persistence of viruses in three effluent-dominated streams. Samples were collected from the effluent outfall of three wastewater treatment plants in the Western United States and downstream at different locations. All samples were tested for the presence of pepper mild mottle virus (PMMoV), adenoviruses, norovirus GI and GII, Aichi virus, and enteroviruses using qPCR. PMMoV was detected most frequently in 54/57 (94.7%) samples, followed by adenoviruses which was detected in 21/57 (36.8%) samples. PMMoV was detected at all locations downstream and up to 32 km from the discharge point. This study demonstrated that the detection signal of PMMoV was able to persist in wastewater discharges to a greater degree than human enteric viruses in effluent-dominated rivers.     

Tympanal mechanics and neural responses in the ears of a noctuid moth

Ears evolved in many groups of moths to detect the echolocation calls of predatory bats. Although the neurophysiology of bat detection has been intensively studied in moths for decades, the relationship between sound-induced movement of the noctuid tympanic membrane and action potentials in the auditory sensory cells (A1 and A2) has received little attention. Using laser Doppler vibrometry, we measured the velocity and displacement of the tympanum in response to pure tone pulses for moths that were intact or prepared for neural recording. When recording from the auditory nerve, the displacement of the tympanum at the neural threshold remained constant across frequencies, whereas velocity varied with frequency. This suggests that the key biophysical parameter for triggering action potentials in the sensory cells of noctuid moths is tympanum displacement, not velocity. The validity of studies on the neurophysiology of moth hearing rests on the assumption that the dissection and recording procedures do not affect the biomechanics of the ear. There were no consistent differences in tympanal velocity or displacement when moths were intact or prepared for neural recordings for sound levels close to neural threshold, indicating that this and other neurophysiological studies provide good estimates of what intact moths hear at threshold.     

Preservation of ancient DNA in thermally damaged archaeological bone

Evolutionary biologists are increasingly relying on ancient DNA from archaeological animal bones to study processes such as domestication and population dispersals. As many animal bones found on archaeological sites are likely to have been cooked, the potential for DNA preservation must be carefully considered to maximise the chance of amplification success. Here, we assess the preservation of mitochondrial DNA in a medieval cattle bone assemblage from Coppergate, York, UK. These bones have variable degrees of thermal alterations to bone collagen fibrils, indicative of cooking. Our results show that DNA preservation is not reliant on the presence of intact collagen fibrils. In fact, a greater number of template molecules could be extracted from bones with damaged collagen. We conclude that moderate heating of bone may enhance the retention of DNA fragments. Our results also indicate that ancient DNA preservation is highly variable, even within a relatively recent assemblage from contexts conducive to organic preservation, and that diagenetic parameters based on protein diagenesis are not always useful for predicting ancient DNA survival.     

Effects of sheltering fish on growth of their host corals

Stony corals are the foundation species of tropical reefs, and their structures can harbor a diverse range of mutualist taxa that can confer important benefits, including provision of nutrients. Prominent among the associates of branching coral in the genus Pocillopora are groups of zooplanktivorous damselfishes that take refuge in the coral to avoid their predators. In field and laboratory experiments, we explored the effects of colonies of resident damselfishes on growth of their host corals. Laboratory studies revealed a positive relationship between biomass of fish and output of ammonium. In the field, levels of ammonium were significantly elevated in the water surrounding the branches of Pocillopora occupied by colonies of damselfish, particularly in time periods following active feeding by the fish. Experimental manipulation of the presence of fish on host corals during a month-long field experiment revealed that corals hosting fish grew significantly more than those that lacked fish, and coral growth was positively correlated with the biomass of resident fish. The Pocillopora colonies in the field experiment varied in the degree of openness of their branching structure, and dye studies indicated that this affected their ability to retain waterborne nutrients. Together with biomass of resident fish, colony openness explained 76% of the variation in coral growth rate during the experiment. Corals can exhibit considerable morphological variability, and mutualistic fish respond to colony architecture during habitat selection, with some species preferring more open-branched forms. This makes it likely that corals may face tradeoffs in attracting resident fish and in retaining the nutrients they provide.     

The effectiveness of katydid (<Emphasis Type="Italic">Neoconocephalus ensiger</Emphasis>) song cessation as antipredator defence against the gleaning bat <Emphasis Type="Italic">Myotis septentrionalis</Emphasis>

Many nocturnal katydids (Orthoptera: Tettigoniidae) produce intense calling songs, and some bat species use these songs to detect and locate prey. One Nearctic katydid species, Neoconocephalus ensiger, ceases or pauses singing in response to bat echolocation calls. We tested the hypothesis that song cessation is an effective defence against gleaning bats (i.e., bats that take prey from surfaces). We observed Myotis septentrionalis, a sympatric bat species that uses prey-generated sounds when gleaning, attack and feed on singing N. ensiger in an outdoor flight room. These bats demonstrated a preference for the calling song of N. ensiger over a novel cricket calling song when they were broadcast from a speaker in the flight room. Bats attacked speakers broadcasting N. ensiger calling song as long as the song was continuous and aborted their attack if the sound stopped as they approached, regardless of whether a katydid was present as a physical target on the speaker. Echolocation calls were recorded during attacks and no significant differences were found between continuous and interrupted song approaches for four call parameters, suggesting that M. septentrionalis may not use echolocation to locate silent prey. Therefore, song cessation by katydids in response to ultrasound is an effective defence against gleaning bats.