From silence to resilience: prospects and limitations for incorporating non-expert knowledge into hazard management

Despite efforts to include residents in hazard management, their contributions are often undervalued because they are seen as passive recipients of intervention rather than active participants in the production of knowledge, particularly when they lack technical expertise. However, using multiple perspectives and experiences can improve hazard management strategies and create safer communities. This paper examines a Colombian landslide management program to highlight the prospects and limitations of incorporating non-expert knowledge into hazard management. The Guardianas de la Ladera (Guardians of the Slope) in Manizales, Colombia is a program in which female heads of household are hired to maintain landslide-prevention infrastructure and communicate landslide risk to the community. While the highly regarded program is perceived as having reduced the frequency of landslides and associated damages, the hierarchical institutional structure inhibits bottom-up communication, including information that could improve long-term vulnerability reduction. We argue that regardless of the location, scale, or specific hazard being addressed, incorporating non-expert knowledge into hazard management potentially illuminates sources of vulnerability not recognized by technical or development experts.     

Streamflow Depletion Modeling: Methods for an Adaptable and Conjunctive Water Management Decision Support Tool

Groundwater pumping depletes streamflow, which can have significant ecological impacts depending on the magnitude of depletion relative to environmental flow needs. Streamflow depletion estimates from groundwater pumping have been quantified using both analytical and numerical methods, but are not routinely compared to environmental flow needs or used in practical water management tools. Decision support tools that incorporate groundwater dynamics are becoming increasingly necessary for water managers as groundwater regulations become more important in environmental policy, particularly concerning the preservation of environmental flow needs. We develop and apply methods for a web‐based decision support tool for conjunctive groundwater and surface water management, demonstrated using a case study watershed in British Columbia, Canada. Open‐source data are analyzed with a combination of spatial algorithms and previously developed analytical models, such that the tool can be applied to other regions. Streamflow depletion estimates are calculated in four regions in the largely undeveloped Bulkley Valley, British Columbia. Our transparent methodology has geographic and data input flexibility which is a significant improvement on currently existing water management tool methods.     

The Effects of Three Chemical Algaecides on Cell Numbers and Toxin Content of the Cyanobacteria Microcystis aeruginosa and Anabaenopsis sp.

Toxic cyanobacteria blooms are a growing concern for public health and safety, due in part to the production of the hepatotoxin microcystin by certain species, including Microcystis aeruginosa. Management strategies for controlling cyanobacteria blooms include algaecide treatments, often with copper sulfate, and more recently oxidizers such as sodium percarbonate that produce hydrogen peroxide. This study assessed the effects of two copper-containing algaecides and one sodium percarbonate-containing algaecide on mitigating cell numbers and toxin content of cultured M. aeruginosa and summer (July) bloom samples of Anabaenopsis sp. in a brackish stormwater detention pond. Monitoring of the bloom revealed that Anabaenopsis sp. was associated with elevated levels of orthophosphate compared to nitrogen (dissolved inorganic nitrogen to phosphorus ratios were 0.19–1.80), and the bloom decline (September–October) was likely due to lower autumn water temperatures combined with potential grazing by the dinoflagellate Protoperidinium quinquecorne. Laboratory-based algaecide experiments included three dose levels, and cyanobacteria cell numbers and microcystin concentrations (particulate and dissolved) were evaluated over 7 d. Following exposure, copper-containing treatments generally had lower cell numbers than either sodium percarbonate-containing or control (no algaecide) treatments. Addition of algaecides did not reduce overall microcystin levels, and a release of toxin from the particulate to dissolved phase was observed in most treatments. These findings indicate that algaecide applications may visibly control cyanobacteria bloom densities, but not necessarily toxin concentrations, and have implications for public health and safety.     

Rice versus fish revisited: On the integrated management of floodplain resources in Bangladesh

Disproportionately little attention has been paid to the dry season trade‐off between rice and (inland capture) fish production on the floodplains of Bangladesh, compared to the same trade‐off during the flood season. As the rural economy grows increasingly dominated by dry‐season irrigated rice production, and floodplain land and water come under ever‐increasing pressure during the dry winter months, there is an urgent need to focus attention on these dry months that are so critical to the survival and propagation of the floodplain resident fish, and to the poor people that depend on these fish for their livelihood. This article examines three important dry‐season natural resource constraints to floodplain livelihoods in Bangladesh, and finds a common factor at the heart of all three: rice cultivation on lands at low and very low elevations. The article articulates the system interlinkages that bind these constraints and the long‐run trend towards irrigated rice cropping on lower‐lying lands, and suggests a management approach based on locally tailored strategies to arrest this trend. Apart from its direct relevance to the floodplains of Bangladesh, which support more than 100 million people, these lessons have relevance for river floodplain systems elsewhere in the developing world, notably the Mekong Delta.     

Forestry-based carbon sequestration projects in Africa: Potential benefits and challenges

Carbon sequestration through forestry and agroforestry can help mitigate global warming. For Africa, carbon sequestration also represents an opportunity to fund sustainable development through financial inflows. However, with a low share of global carbon trade, there are strong concerns that African countries are losing out on this valuable opportunity. Through a comprehensive review of 23 carbon sequestration projects across 14 countries, this paper discusses ways to overcome critical challenges to scale up carbon investments in Africa. These projects are expected to sequester 26.85 million tCO₂ beyond the baseline situation. Within the continent, East Africa is the preferred destination for carbon investors. Most projects are non‐Kyoto compliant and represent voluntary emission reductions. While project benefits such as increased local incomes and improved natural resources are promising, there are concerns that conversion of grasslands into tree plantations can harm local ecosystems. Insecure land tenure constrains new investments and increases the risk that local communities will lose access to forests. Another challenge is that projects with smallholders have high transaction costs. These costs can be overcome by building strong community institutions and simplifying project guidelines. To attract more projects, African governments will need to build their capacity to identify relevant opportunities.     

A brief history of phosphorus: from the philosopher's stone to nutrient recovery and reuse

The element phosphorus has no substitute in sustaining all life and food production on our planet. Yet today’s phosphorus use patterns have resulted in both a global environmental epidemic of eutrophication and led to a situation where the future availability of the world’s main sources of phosphorus is uncertain. This paper examines the important history of human interference with the phosphorus cycle from initial discovery to present, highlighting key interrelated events and consequences of the Industrial Revolution, Sanitation Revolution and Green Revolution. Whilst these events led to profound advances in technology, public health and food production, they have fundamentally broken the global phosphorus cycle. It is clear a ‘Fourth Revolution’ is required to resolve this dilemma and ensure humanity can continue to feed itself into the future while protecting environmental and human health.     

Dissolution and sorption of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT) residues from detonated mineral surfaces

Composition B (Comp B) is a commonly used military formulation composed of the toxic explosive compounds 2,4,6-trinitrotoluene (TNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Numerous studies of the temporal fate of explosive compounds in soils, surface water and laboratory batch reactors have been conducted. However, most of these investigations relied on the application of explosive compounds to the media via aqueous addition and thus these studies do not provide information on the real world loading of explosive residues during detonation events. To address this we investigated the dissolution and sorption of TNT and RDX from Comp B residues loaded to pure mineral phases through controlled detonation. Mineral phases included nontronite, vermiculite, biotite and Ottawa sand (quartz with minor calcite). High Performance Liquid Chromatography and Attenuated Total Reflectance Fourier Transform Infrared spectroscopy were used to investigate the dissolution and sorption of TNT and RDX residues loaded onto the mineral surfaces. Detonation resulted in heterogeneous loading of TNT and RDX onto the mineral surfaces. Explosive compound residues dissolved rapidly (within 9 h) in all samples but maximum concentrations for TNT and RDX were not consistent over time due to precipitation from solution, sorption onto mineral surfaces, and/or chemical reactions between explosive compounds and mineral surfaces. We provide a conceptual model of the physical and chemical processes governing the fate of explosive compound residues in soil minerals controlled by sorption-desorption processes.     

Town-scale microbial sewer community and H2S emissions response to common chemical and biological dosing treatments

Controlling hydrogen sulfide(H₂S) odors and emissions using a single,effective treatment across a town-scale sewer network is a challenge faced by many water utilities.Implementation of a sewer diversion provided the opportunity to compare the effectiveness of magnesium hydroxide(Mg(OH)₂) and two biological dosing compounds(Bioproducts A and B),with different modes of action(MOA),in a field-test across a large sewer network.Mg(OH)₂ increases sewer p H allowing su...     

The Effects of Small Dam Removal on the Distribution of Sedimentary Contaminants

With increasing concern over degradation of aquatic resources, issues of liability, and maintenance costs, removal of small dams has become increasing popular. Although the benefits of removal seem to outweigh the drawbacks, there is a relative paucity of studies documenting the extent and magnitude of biological and chemical changes associated with dam removal, especially those evaluating potential changes in contaminant inventories. In August and November of 2000, a run-of-the-river dam on Manatawny Creek (southeast Pennsylvania) was removed in a two-stage process. To assess the effects of dam removal on the contaminant redistribution within the creek, sedimentary concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and trace metals (Cd, Cr, Cu, Ni, Pb, Zn) were evaluated prior to and several months after removal. Pre- and post-removal analyses revealed elevated and spatially variable concentrations of total PAHs (ranging from approximately 200 to 81,000 ng(g dry weight) and low to moderate concentrations of trace metals and PCBs. The concentrations of these sedimentary contaminants pre- versus post-removal were not significantly different. Additionally, though the impoundment received storm water run-off and associated contaminants from the adjacent city of Pottstown, the total inventory of fine-grain sediments in the impoundment prior to removal was very low. The removal of the low-level Manatawny Creek dam did not significantly redistribute contaminants downstream. However, each dam removal should be assessed on a case by case basis where the potential of sedimentary contaminant redistribution upon dam removal exists.     

Trace-level beryllium analysis in the laboratory and in the field: state of the art, challenges and opportunities

Control of workplace exposure to beryllium is a growing issue in the United States and other nations. As the health risks associated with low-level exposure to beryllium are better understood, the need increases for improved analytical techniques both in the laboratory and in the field. These techniques also require a greater degree of standardization to permit reliable comparison of data obtained from different locations and at different times. Analysis of low-level beryllium samples, in the form of air filters or surface wipes, is frequently required for workplace monitoring or to provide data to support decision-making on implementation of exposure controls. In the United States and the United Kingdom, the current permissible exposure level is 2 microg m(-3) (air) and the United States Department of Energy has implemented an action level of 0.2 microg m(-3) (air) and 0.2 microg/100 cm(2) (surface). These low-level samples present a number of analytical challenges, including (1) a lack of suitable standard reference materials, (2) unknown robustness of sample preparation techniques, (3) interferences during analysis, (4) sensitivity (sufficiently low detection limits), (5) specificity (beryllium speciation) and (6) data comparability among laboratories. Additionally, there is a need for portable, real-time (or near real-time) equipment for beryllium air monitoring and surface wipe analysis that is both laboratory-validated and field-validated in a manner that would be accepted by national and/or international standards organizations. This paper provides a review of the current analytical requirements for trace-level beryllium analysis for worker protection and also addresses issues that may change those requirements. The current analytical state of the art and relevant challenges facing the analytical community will be presented, followed by suggested criteria for real-time monitoring equipment. Recognizing and addressing these challenges will present opportunities for laboratories, research and development organizations, instrument manufacturers and others.