Policy planning under uncertainty: efficient starting populations for simulation-optimization methods applied to municipal solid waste management

Evolutionary simulation-optimization (ESO) techniques can be adapted to model a wide variety of problem types in which system components are stochastic. Grey programming (GP) methods have been previously applied to numerous environmental planning problems containing uncertain information. In this paper, ESO is combined with GP for policy planning to create a hybrid solution approach named GESO. It can be shown that multiple policy alternatives meeting required system criteria, or modelling-to-generate-alternatives (MGA), can be quickly and efficiently created by applying GESO to this case data. The efficacy of GESO is illustrated using a municipal solid waste management case taken from the regional municipality of Hamilton-Wentworth in the Province of Ontario, Canada. The MGA capability of GESO is especially meaningful for large-scale real-world planning problems and the practicality of this procedure can easily be extended from MSW systems to many other planning applications containing significant sources of uncertainty.     

Pediatric pedestrian trauma study: a pilot project

OBJECTIVE: To evaluate the implementation of the WalkSafe Program, a school based educational injury prevention program for children grades Kindergarten through 5. METHODS: A randomized comparative design was used for this study. The study was conducted in two high-risk urban school districts, which were chosen based on the geographic areas with the highest pedestrian injury and fatality rates. Four elementary schools (two in each district) were identified as potential study sites. Two intervention schools, one in each school district, were randomly chosen to receive the WalkSafe program; the other two schools served as controls, and received no intervention. The data was collected within the classroom setting for both the intervention and control schools. All elementary school children were administered the same pedestrian safety questionnaire as a pre-test, post-test and at three months following the intervention. RESULTS: A total of 2300 children participated in the WalkSafe program. The intervention (I) schools showed significant improvement in post-test scores then the control (C) schools (p = 0.012), and the (I) schools were able to maintain their test scores as reflected in a three-month follow-up evaluation (p = 0.47). Grades 3-5 of the (I) schools showed significant improvement in their test scores over grades K-2 (p < 0.0001). CONCLUSION: The WalkSafe program was shown to improve the pedestrian safety knowledge of elementary school children. Future research will include implementing the WalkSafe program at each elementary school within a single high-risk district.     

Revegetation of an abandoned uranium millsite on the Colorado Plateau, Arizona

We attempted to restore native plants on disturbed sites at a former uranium mill on the Colorado Plateau near Tuba City, AZ. Four-wing saltbush [Atriplex canescens (Pursh) Nutt.] was successfully established in compacted caliche soil and in unconsolidated dune soil when transplants were irrigated through the first summer with 20 L/plant/wk. The caliche soil was ripped before planting to improve water-holding capacity. The diploid saltbush variety, angustifolia, had higher survival and growth than the common tetraploid variety, occidentalis, especially on dune soil. The angustifolia variety grew to 0.3 to 0.4 m3 per plant over 3 yr even though irrigation was provided only during the establishment year. By contrast, direct seeding of a variety of native forbs, grasses, and shrubs yielded poor results, despite supplemental irrigation throughout the first summer. In this arid environment (precipitation = 100 to 200 mm/yr), the most effective revegetation strategy is to establish keystone native shrubs, such as four-wing saltbush, using transplants and irrigation during the establishment year, rather than attempting to establish a diverse plant community all at once.     

Cyanide residue levels in extracted honey, comb honey and wax cappings.

Cyanide (CN) residue levels were determined in samples of extracted honey, comb honey and was cappings at 1 hr, 24 hr, and 48 hr intervals after destroying the bees in honey bee colonies with normal (ca. 8.5 g) and twice normal (ca. 17 g) doses of CyanogasR A-dust. Applications of CyanogasR A-dust, administered by means of a dust pump at normal and twice normal doses, gave an average residue of 0.01 and 0.04 microgram CN/g of extracted honey, 0.01 and 0.02 microgram CN/g of comb honey and 0.04 and 0.06 microgram CN/g of wax cappings, respectively. When the CyanogasR A-dust (ca. 17 g) was placed on a tray and placed on the bottom board of the hive, the average residue levels for extracted honey, comb honey and wax cappings were less than 0.004, 0.01 and 0.02 microgram CN/g, respectively. Random honey samples from beekeepers, who used CyanogasR to destroy bees, had a median level of 0.031 microgram CN/g, whereas honey from a packing plant and other commercial samples contained less than 0.004--0.026, median less than 0.004 microgram CN/g. Based on residue data from this study, the temporary registration for CyanogasR, to kill honey bees after crop removal, was revised to a full registration in May 1977.     

Marginalization by collaboration: Environmental justice as a third party in and beyond CALFED

Governance and planning of ecosystem and water management within the California Bay-Delta, a critical component of California's water economy, have been characterized by a range of innovations in collaboration and conflict resolution. Despite legal mandates to incorporate environmental justice, the California Bay-Delta Authority's (CBDA) policy-development process and the subsequent Delta Vision process have systematically marginalized the role of environmental justice in California's water policy. We suggest that environmental justice in Bay-Delta planning can be understood as a “third party” with a tenuous seat at the CALFED water management table. As such environmental justice is a useful lens through which to assess the state's broader commitments and capacities relative to equity as a planning principal and outcome. We interpret the fate of environmental justice within Bay-Delta planning as indicative of the inherent tensions between systems based on increasing market dominance and state legitimation and the values of environmental justice based on distributive, procedural, and cognitive justice. We construct a model of marginalization and environmental injustice in collaborative planning to illustrate these tensions. We draw upon experiences of members of the Environmental Justice Sub-Committee of CBDA's Bay Delta Public Advisory Committee, as well as interviews with other key environmental justice interests, and a comprehensive review of internal and public CBDA documents relating to the environmental justice program including budgets and program plans, and ethnographic field work. We conclude that by learning from the mistakes of Bay-Delta planning, a positive model of collaborative, environmental justice-based planning for water and ecosystem management is possible.     

No evidence for sperm priming responses under varying sperm competition risk or intensity in guppies

Sperm competition theory predicts that males should tailor their investment in ejaculates according to the number of rival males competing to fertilize a female’s eggs. Research spanning several taxa supports this prediction by showing that males are often sensitive to the level of sperm competition and adjust their investment in sperm numbers accordingly. More recent work has revealed that males may also tailor the quality of sperm according to the number of males competing for fertilization. Here I test for both effects in guppies (Poecilia reticulata) in an experiment that simultaneously evaluates the risk and intensity models of sperm competition. The experiment determined whether male guppies adjust the number (stripped ejaculate size) and quality (sperm velocity and viability) of sperm that are primed over a 3-day period according to experimental changes in the perceived level of sperm competition. A total of 136 focal males were initially stripped of all retrievable sperm and assayed for these sperm traits before being allocated at random to one of four treatments simulating different levels of sperm competition risk and intensity. During the 3-day treatment phase, focal males had visual and olfactory access to a sexually receptive (initially virgin) female maintained with different numbers of stimulus males to simulate variation in the risk and intensity of sperm competition. Following this, males were assayed again for the sperm traits. Contrary to predictions, there was no significant change in any of the measured variables among treatments, although qualitatively the patterns for sperm velocity and viability did conform to expectation. The lack of any trend for the number of sperm primed was unequivocal and future work examining the effects of sperm competition on sperm production should focus on whether males differentially allocate sperm numbers among matings that differ in the level of sperm competition.     

Intraspecific trait variants determine the nature of interspecific interactions in a habitat-forming species

Although the study of ecological interactions often takes into account functional variation between species, intraspecific variation is commonly ignored. Here, we investigate the importance of an intraspecific polymorphism in shaping interspecific interactions in a habitat-building species. Colonies of the social spider Anelosimus studiosus provide habitat for dozens of arthropod species, and colony members exhibit markedly polymorphic behavioral temperaments (BT): "aggressive" or "docile." We manipulated the phenotypic compositions of colonies (100% aggressive, 50% aggressive and 50% docile, 100% docile) and measured the nature and magnitude of interactions between A. studiosus and two heterospecific web associates, Larinioides cornutus and Agelenopsis emertoni. We found that BT composition significantly affected the outcome of interspecific interactions, changing the relationship between A. studiosus and its web associates from an ammensalism (where A. studiosus experiences reduced fecundity and survival) to a commensalism or mutualism. Our study successfully illustrates the potential of BTs to impact whole community dynamics, and conversely, for community structure to influence the maintenance of BTs.