Price Endogeneity and Marginal Cost Effects on Incentive Compatible Stormwater Management Policies

Incentive based stormwater management policies offer the prospect of reducing urban stormwater runoff while increasing developer profits. An incentive compatible Stormwater Banking Program (SBP) is presented that allows developers to build at higher residential densities in exchange for including low impact stormwater Best Management Practices (BMPs) in the development’s stormwater management infrastructure. Price endogeneity presents itself when the smaller residential lots created by building at a greater density sell for a lower price than the original, larger lots. Stormwater management authorities must be aware of this and the effects of the program participation fee structure in designing voluntary incentive based policies that meet runoff reduction objectives.Farm Management,

Incentive Policies to Promote the Use of Enhanced Stormwater BMPs in New Residential Developments

A voluntary stormwater management program that is incentive compatible between residential developers and regulators produces an outcome that simultaneously protects/enhances water quality and increases developer profits. Developers pay a participation fee and the collected fees are used to retrofit ineffective stormwater management systems in older neighborhoods to improve water quality.Stormwater Best Management Practices, Economic Incentives, Urban Water Quality, Environmental Economics and Policy, Q25,

Perennial Cereals: A Novel Source of Feed for Grazing Livestock

Initial deployment of perennial cereal crops will likely be as a dual-purpose crop producing forage for livestock as well as grain. This study evaluated the biomass and grain production of 4 wheat × wheatgrass derivative experimental lines under 4 simulated grazing regimes; nil defoliation (D0), defoliate once (D1), defoliate twice (D2) and defoliate twice followed by a simulated hay cut (D3), and compared performance to a winter wheat, cv. EGA Wedgetail, and the perennial grass Thinopyrum intermedium. Increasing defoliation intensity significantly (P \u3c 0.001) lengthened the time to flowering for all lines. All experimental lines produced less biomass in the first year than EGA Wedgetail but more than Th. intermedium in the first spring. Grain yield from Wedgetail was significantly higher (P \u3c 0.001) than all other lines except in the D3 treatment. As defoliation intensity increased, the comparative difference in grain yield between Wedgetail and the experimental entries decreased, with experimental lines OK 7211542 and 11955 exceeding the grain yield of EGA Wedgetail in the D3 treatment. Cumulative biomass production of the experimental lines exceeded that of Wedgetail (P = 0.005), though the distribution of production, across seasons differed markedly. This paper discusses the opportunities perennial cereals may offer as a novel forage source in a mixed-farming context

Summer Dormancy Expression in the Australian Native Grass \u3cem\u3eElymus scaber\u3c/em\u3e

Complete summer dormancy is associated with plant senescence in late spring-summer even though soil moisture is non-limiting. The trait is well understood in exotic temperate grasses for persistence in environments which experience frequent summer droughts (Annicchiarico et al. 2011). However, the trait appears to be uncommon in Australian native grasses (Culvenor 2009). The C3 native perennial grass, Elymus scaber, is broadly adapted across a wide range of climatic zones and soil types in south eastern Australia (Johnston et al. 2001) and has been described as displaying strong summer dormancy (Mitchell et al. 2001). However, the reports of dormancy were not tested under conditions of non-limiting soil moisture. Therefore the dormancy aspect of its growth habit over summer may be confused with drought avoidance, causing leaf senescence in response to drying soil. This study tested the hypothesis that E. scaber exhibits traits consistent with complete summer dormancy, by placing a range of populations of the species under three irrigation regimes (after Norton et al. 2006). For E. scaber to demonstrate complete summer dormancy, it would show no new growth over summer irrespective of the irrigation treatment

Climate-driven regime shifts in a mangrove-salt marsh ecotone over the past 250 years.

Climate change is driving the tropicalization of temperate ecosystems by shifting the range edges of numerous species poleward. Over the past few decades, mangroves have rapidly displaced salt marshes near multiple poleward mangrove range limits, including in northeast Florida. It is uncertain whether such mangrove expansions are due to anthropogenic climate change or natural climate variability. We combined historical accounts from books, personal journals, scientific articles, logbooks, photographs, and maps with climate data to show that the current ecotone between mangroves and salt marshes in northeast Florida has shifted between mangrove and salt marsh dominance at least 6 times between the late 1700s and 2017 due to decadal-scale fluctuations in the frequency and intensity of extreme cold events. Model projections of daily minimum temperature from 2000 through 2100 indicate an increase in annual minimum temperature by 0.5 °C/decade. Thus, although recent mangrove range expansion should indeed be placed into a broader historical context of an oscillating system, climate projections suggest that the recent trend may represent a more permanent regime shift due to the effects of climate change

Incentive Compatible Policies to Promote Voluntary Use of Enhanced Stormwater BMPs in New Residential Developments

2010 S.C. Water Resources Conference - Science and Policy Challenges for a Sustainable Futur

Yellotas: A Unique Yellow Serradella Cultivar With Potential for Permanent Pasture Environments

Yellow serradella (Ornithopus compressus L.) has been identified as a priority self-regenerating annual legume species for permanent pasture environments in south-eastern Australia. However, most yellow serradella genotypes exhibit high levels of hard seed and slow rates of hard seed breakdown, which reduces regeneration density in the years following the year of sowing . One cultivar, Yellotas, exhibits a much faster rate of hard seed breakdown and has been identified as one of only a handful of cultivars of that species with promising persistence in permanent pasture environments. In addition, this cultivar is substantially easier to de-hull than other cultivars of that species, potentially reducing seed costs. In a field evaluation under severe drought conditions, this cultivar was shown to exhibit a high level of tolerance to close grazing. Yet, doubt still exists as to whether cv. Yellotas produces sufficient residual hard seed to withstand periodic drought suggesting further improvement may be required. This paper details the origins of cultivar and observations of its performance under a range of conditions in south-eastern Australia

The differential importance of deep and shallow seagrass to Nekton assemblages of The Great Barrier Reef

Seagrass meadows are an important habitat for a variety of animals, including ecologically and socioeconomically important species. Seagrass meadows are recognised as providing species with nursery grounds, and as a migratory pathway to adjacent habitats. Despite their recognised importance, little is known about the species assemblages that occupy seagrass meadows of different depths in the coastal zone. Understanding differences in the distribution of species in seagrass at different depths, and differences in species diversity, abundance, biomass, and size spectra, is important to fully appreciate both the ecological significance and economic importance of these seagrass meadows. Here, we assess differences in the assemblage characteristics of fish, crustacea, and cephalopods (collectively, nekton) between deep ( > 9 m; Halophila spinulosa dominant) and shallow water ( < 2 m; Halodule uninervis and/or Zostera muelleri dominant) seagrass meadows of the central Great Barrier Reef coast of Queensland, Australia. Nekton assemblage structure differed between deep and shallow seagrass. Deeper meadows were typified by juvenile emperors (e.g., Lethrinus genivittatus), hairfinned leatherjacket (Paramonacanthus japonicus) and rabbitfish (e.g., Siganus fuscescens) in both biomass per unit effort (BPUE) and catch per unit effort (CPUE), whereas shallow meadows were typified by the green tiger prawn (Penaeus semisulcatus) and pugnose ponyfish (Secutor insidiator) in both BPUE and CPUE. Both meadow depths were distinct in their nekton assemblage, particularly for socioeconomically important species, with 11 species unique to both shallow and deep meadows. However, both meadow depths also included juveniles of socioeconomically important species found in adjacent habitats as adults. The total nekton CPUE was not different between deep and shallow seagrass, but the BPUE and body mass of individual animals were greater in deep than shallow seagrass. Size spectra analysis indicated that in both deep and shallow meadows, smaller animals predominated, even more so than theoretically expected for size spectra. Our findings highlight the unique attributes of both shallow and deeper water seagrass meadows, and identify the distinct and critically important role of deep seagrass meadows within the Great Barrier Reef World Heritage Area (GBRWHA) as a habitat for small and juvenile species, including those of local fisheries value

A transient positive association between direct-acting antiviral therapy for hepatitis C infection and drug-related hospitalization among people who inject drugs: self-controlled case-series analysis of national data

Background and Aims: Direct-acting antiviral (DAA) treatment has an established positive effect on liver outcomes in people with hepatitis C infection; however, there is insufficient evidence regarding its effects on the 'extra-hepatic' outcomes of drug-related hospitalization and mortality (DRM) among people who inject drugs (PWID). We investigated associations between these outcomes and DAA treatment by comparing post-treatment to baseline periods using a within-subjects design to minimize selection bias concerns with cohort or case-control designs.Design: This was a self-controlled case-series study.Setting: Scotland, 1 January 2015-30 November 2020.Participants: The study population of non-cirrhotic, DAA-treated PWID was identified using a data set linking Scotland's hepatitis C diagnosis, HCV clinical databases, national inpatient/day-case hospital records and the national deaths register. Three principal outcomes (drug overdose admission, non-viral injecting related admission and drug-related mortality) were defined using ICD codes.Measurements: Self-controlled case-series methodology was used to estimate the relative incidence (RI) of each outcome associated with time on treatment and up to six 90-day exposure risk periods thereafter.Findings: A total of 6050 PWID were treated with DAAs in the sampling time-frame. Compared with the baseline period, there was a significantly lowered risk of a drug overdose hospital admission in the second to fifth exposure risk periods only [relative incidence (RI) = 0.86, 95% confidence interval (CI) = 0.80-0.99; 0.89, 95% CI = 0.80-0.99; 0.86, 95% CI = 0.77-0.96; 0.88, 95% CI = 0.78-0.99, respectively]. For non-viral injecting-related admission, there was a reduced risk in the first, third and fourth exposure risk periods (RI = 0.76, 95% CI = 0.64-0.90; 0.75, 95% CI = 0.62-0.90; 0.79, 95% CI = 0.66-0.96, respectively). There was no evidence for reduced DRM risk in any period following treatment end.Conclusions: Among people who inject drugs in Scotland, direct-acting antiviral treatment appears to be associated with a small, non-durable reduction in the risk of drug-related hospital admission, but not drug-related mortality. Direct-acting antiviral therapy, despite high effectiveness against liver disease, does not appear to offer a panacea for reducing other drug-related health harms.</p