Wetland assessment and impact mitigation decision support framework for linear development projects: The Louis Riel Trail,Highway 11 North project,Saskatchewan, Canada

Next to agriculture, road development is one of the most significant sources of stress to wetlands in Prairie Canada. However, there currently exists limited guidance for incorporating direct, indirect, and induced effects to wetlands in impact assessment and mitigation planning for small and often routine developments, including access roads or highway improvement initiatives. Based on the Louis Riel Trail, Highway 11 North twinning project in Saskatchewan, Canada, this article demonstrates a methodological approach and decision support framework for assessing and managing direct, indirect, and induced effects to wetlands from linear developments. No regulatory‐based environmental assessment was required for the highway project; effects were deemed to be insignificant under current wetland mitigation practices. However, our results show that 1115 ha of potentially affected wetlands are located within a 500 m impact zone on either side of the proposed highway. More than 50 percent of these wetlands are seasonal, less than 1 ha in size, and typically not included in mitigation planning. An expert‐based multi‐criteria evaluation of impact and mitigation options for wetlands in the study area indicated “no net loss” as a planning priority, and a preference for a spatially ambitious mitigation plan focused on direct, indirect, and potentially induced impacts. In practice, however, mitigation is often restrictive, focused on mitigating only direct impacts within the project's right‐of‐way, in this case less than 50 ha of wetlands, resulting in the potential for significant net loss of wetland habitat and function. If the risk to wetlands is to be given due consideration in project planning and development for roads and road improvement initiatives, then structured assessment methods and decision support frameworks should be sensitive to the time and resource constraints of small projects and screening‐type assessments. This requires also that wetland mitigation policies are developed and implementation plans formulated as part of project planning and assessment initiatives for linear developments.     

A study of limestone from the Longmen Grottoes of Henan province,China by neutron activation analysis

The Longmen Grottoes, also known as the Longmen Caves or Dragon's Gate Grottoes, are located near the city of Luoyang, Henan province, China. The grottoes were carved into the limestone cliffs during the period from 493 AD to 1130 AD. Limestone samples from different areas within the grottoes were analyzed by neutron activation analysis (NAA) to determine the concentrations of major, trace and rare-earth elements (REEs). Three compositional groups were identified corresponding to different areas within Longmen Grottoes. X-ray diffraction (XRD) was performed on a few samples to obtain information about the mineral structure. The results indicate that rocks in the northern area are comprised of dolomite, while rocks in the middle and southern areas are comprised of limestone. The NAA results provide information useful for identifying and relocating fragments from the grottoes that may have lost their identity. The compositional data also provides important clues regarding the geologic history of the limestone formation at Longmen.     

Preliminary characterization and regional comparison of the Dasht-i-Nawur obsidian source near Ghazni,Afghanistan

Archaeologists have known that an obsidian source exists in the Dasht-i-Nawur basin of central Afghanistan since at least the 1970s; however, regional political turmoil and instability have prevented in-depth study of this source. Data presented here from recent analyses of archival specimens of obsidian collected during a 1976 survey provide a preliminary geochemical profile for this obsidian source. These data suggest that the Dasht-i-Nawur source is easily distinguishable from other obsidian sources in the Near East and southwest Asia. Comparison of these data to an existing database of artifact compositional profiles suggests that initial hypotheses about restricted distribution of the Dasht obsidian may be correct. These data provide for the first time the characterization of a long-known but poorly studied obsidian source. Additionally, this study serves as one example of the benefits gained through working to maintain and preserve data archives of now-closed laboratories.     

An experimental approach to the study of interpersonal violence in Northeastern Patagonia (Argentina), during the late Holocene

This paper incorporates an experimental approach to the study of violence patterns in Northeastern Patagonia (Argentina) during the late Holocene. The underlying hypothesis considers a close association between socio-ecologic alterations during the Medieval Climatic Anomaly (MCA) (ca. 1150-600 years BP; Stine, 1994, 2000) and a probable increase in conflict levels. In order to test this hypothesis, human skulls (n = 986) were analyzed for bone lesions, discriminating late bone lesions, such as those produced by metal tools. The experimental approach used swine (Sus scrofa domestica) skulls, as proxies for human skulls, and incorporated original sabers. From this discriminating analysis, it can be inferred that no significant increase in violence signs were recorded until the first stages of Hispanic-indigenous contact (first half of 17th century). These findings emphasize the need for a revision of the implications of the dynamics of human populations in Northeastern Patagonia during the late Holocene.     

The Determinants of Policy Introduction and Bill Adoption: Examining Minimum Wage Increases in the American States, 1997–2006

Faced with long intervals between federal minimum wage increases in recent years, state legislatures are increasingly likely to take action. Motivated by the relative dearth of empirical work on minimum wages in the American states, this article considered various explanations to determine which factors are associated with legislative efforts to pass wage increases. Taking seriously the view that disagreements over the effects of minimum wage increases enhances the influence of political factors, we drew on the policy adoption and diffusion literature to examine how internal determinants (political and economic variables) and regional diffusion pressures relate to both the introduction and adoption of minimum wage legislation in the American states in the years between the last two federal minimum wage increases (1997–2006). Employing negative binomial regression to analyze annual bill introductions, we found that a number of political variables are related to the consideration of minimum wage increases. However, using event history analysis to examine annual adoptions of minimum wage increases, we found few of the same variables matter. We concluded with a discussion of the empirical results within the context of the broader policy literature and cautioned future scholars to consider seriously whether political factors exert distinct influences at different stages of the policy process.     

Multi-Component Seismic Response Analysis – A Critical Review

Issues related to multi-components seismic response analysis are critically reviewed and their implications with respect to the current codified approaches are studied. The issues specifically addressed are: (1) the directions of earthquake forces to excite a structure when the direction of the potential epicenter is known; (2) different commonly used combination rules to obtain the critical response when responses are available in different directions; and (3) the applicability of the combination rules for elastic and inelastic analyses. Based on an extensive parametric study consisting of three-dimensional 1-, 3-, 8-, and 15- story buildings made of moment-resisting steel frames and 20 recorded earthquakes, it is observed that the principal components produce larger responses than the normal components. The 30% and SSRS rules generally underestimate the axial loads in columns. The 30% combination rule is slightly better than the SSRS rule. For both rules, the uncertainty in the estimation of the axial loads in terms of COV is very large (about 25%). The statistics obtained for axial loads and total base shear indicate that the combination rules are applicable for both elastic and inelastic cases. The critical response could be obtained for an orientation different from that of the principal components. The differences are found to be slightly greater for the scaled earthquakes producing a considerable inelastic behavior. Considering the enormous amount of efforts needed to address the directionality effect, it is believed that the responses obtained by the principal components will be acceptable in most cases; however, for critical structures the components should be rotated to obtain the critical responses.