Wetlands and low-gradient topography are associated with longer hydrologic transit times in Precambrian Shield headwater catchments

The estimation of hydrologic transit times in a catchment provides insights into the integrated effects of water storage, mixing dynamics, and runoff generation processes. There has been limited effort to estimate transit times in southern boreal Precambrian Shield landscapes, which are characteristically heterogeneous with surface cover including till, thin soils, bedrock outcrops, and depressional wetland features that play contrasting hydrologic roles. This study presents approximately 3.5 years of precipitation and streamflow water isotope data and estimates mean transit times (MTTs) and the young water fraction (p_y) across six small catchments in the Muskoka-Haliburton region of south-central Ontario. The main objectives were to define a typical range of MTTs for headwater catchments in this region and to identify landscape variables that best explain differences in MTTs/p_y using airborne light detection and ranging and digital terrain analysis. Of the transit time distributions, the two parallel linear reservoir and gamma distributions best describe the hydrology of these catchments, particularly because of their ability to capture more extreme changes related to events such as snowmelt. The estimated MTTs, regardless of the modelling approach or distribution used, are positively associated with the percent wetland area and negatively with mean slope in the catchments. In this landscape, low-gradient features such as wetlands increase catchment scale water storage when antecedent conditions are dryer and decrease transit times when there is a moisture surplus, which plausibly explains the increases in MTTs and mean annual runoff from catchments with significant coverage of these landscape features.     

Controls on the chemistry of runoff from an upland peat catchment

This study uses 2 years of data from a detailed weekly water sampling programme in a 11·4 km² upland peat catchment in the Northern Pennines, UK. The sampling comprised precipitation, soil‐water samples and a number of streams, including the basin outlet. Samples were analysed for: pH, conductivity, alkalinity, Na, K, Ca, Mg, Fe, Al, Total N, SO₄, Cl and colour. Principal component analysis (PCA) was used to identify end‐members and compositional trends in order to identify controls on the development of water composition. The study showed that the direct use of PCA had several advantages over the use of end‐member mixing analysis (EMMA) as it combines an analysis of mixing and evolving waters without the assumption of having to know the compositional sources of the water. In its application to an upland peat catchment, the study supports the view that shallow throughflow at the catotelm/acrotelm boundary is responsible for storm runoff generation and shows that baseflow is controlled by cation exchange in the catotelm and mixing with a base‐rich groundwater. Copyright © 2003 John Wiley & Sons, Ltd.     

Middle Stone Age starch acquisition in the Niassa Rift, Mozambique

The quest for direct lines of evidence for Paleolithic plant consumption during the African Middle Stone Age has led scientists to study residues and use-wear on flaked stone tools. Past work has established lithic function through multiple lines of evidence and the spatial breakdown of use-wear and microscopic traces on tool surfaces. This paper focuses on the quantitative analysis of starch assemblages and the botanical identification of grains from flake and core tools to learn about human ecology of carbohydrate use around the Niassa woodlands, in the Mozambican Rift. The processing of starchy plant parts is deduced from the occurrence of starch assemblages that presumably got attached to stone tool surfaces by actions associated with extractive or culinary activities. Specifically, we investigate starch grains from stone tools recently excavated in northern Mozambique at the site of Mikuyu; which presumably spans the middle to late Pleistocene and represents similar sites found along the Malawi/Niassa corridor that links East, Southern, and Central Africa. Starch was extracted and processed with a diverse tool kit consisting of scrapers, cores, points, flakes, and other kinds of tools. The microbotanical data suggests consumption of seeds, legumes, caryopses, piths, underground storage organs, nuts, and mesocarps from more than a dozen families. Our data suggest a great antiquity for starch use in Africa as well as an expanded diet and intensification.     

The 2002 reform of the Common Fisheries Policy's system of governance—rhetoric or reality?

The 2002 Reform of the Common Fisheries Policy (CFP) was claimed to be a radical overhaul of a failing system. Several EU fish stocks—particularly North Sea cod—had reached dangerously low levels, and there was widespread dissatisfaction with the way in which the CFP was operating. The European Commission took the opportunity of the legal requirement to review some features of the CFP (principally access provisions) in 2002, to undertake a broader reappraisal of the CFP. One of the features of this reappraisal was an attempt to improve the CFP's system of governance by increasing the amount of stakeholder participation, decentralisation, transparency, accountability, effectiveness and coherence. In this paper, the conclusion is reached that this attempt to improve the quality of governance in the 2002 CFP reform package has been more rhetorical than real.     

Asking the right questions: environmental conflict in the case of Azerbaijan

This paper contributes an empirical test of key themes of the literature on natural resource conflict. Survey and interview data from an ongoing project in Azerbaijan provide insights into an unexpected lack of conflict in Azerbaijan related to the environment, resources and energy despite the predictions of resource conflict literature. We contend that questions about public perceptions about the environment and other daily concerns are critical if we are to understand who is likely (or unlikely) to be involved in conflict and why. The data presented in this paper demonstrate that Azerbaijani citizens rank environmental and resource issues among their immediate concerns and their top concerns for the country. However, compared to other day-to-day concerns such as the Nagorno-Karabakh conflict and economic concerns, environment-related concerns do not appear to be sufficient to motivate widespread violent conflict or citizen dissent related to environmental or natural resource conditions.