Parental and alloparental investment in campo flickers (Colaptes campestris campestris): when relatedness comes first

Behavioral Ecology and Sociobiology - Studies with individual rodents have revealed that they display protean (unpredictable) behavior when attacked by an owl. Other studies have revealed that...     

Renewable energies for climate benign fuel production. Powering fuel-cell vehicles

Transportation contributes to energy consumption and greenhouse gas emissions, while sustainable mobility requires reductions in both areas. Alternative fuels from natural gas and from renewable resources can contribute in the mid and long-term to the fuel market for mobile as well as stationary applications. The lack of reliable data on emissions, energy chain efficiencies, and costs demonstrates the need for field tests and demonstration projects. Fuel cells offer the technology to use ‘new fuels’ in a highly efficient way.     

Conservation in Lake Tanganyika, with Special Reference to Underwater Parks

Lake Tanganyika is outstanding among lakes because of the intrinsic value of its fauna and the significance of its natural resources. Reconciliation of resource exploitation and conservation is essential because of changes in the lake environment caused by human activities. Important new initiatives to shape national environmental policies for the lake are taking place. Regional cooperation is required for major lakewide studies, especially in lake circulation and the prevention of pollution, and in adjustment of fisheries objectives to meet conservation as well as economic goals. Basic conservation aims proposed are (1) avoidance of gross changes in natural communities in the lake in general, and (2) retention of the fauna in some parts in an unexploited state, as in underwater parks. Early strategies suggested are the extension of four existing wildlife land parks further into the lake to form underwater parks, and reconnaissance of other potential park sites. Initial ecological and social surveys conducted from the four parks would provide baseline data for management. Underwater park boundaries should as far as possible be determined on an ecological basis to encompass entire local distributions of species populations. A case of alternative boundaries is examined for the Nsumbu Park. Other important planning considerations are the multi-use of parks in addition to fundamental conservation, such as tourism, sport fishing, and specific traditional lake and land uses. Regional cooperation between parks will be important for tourism.     

A wind tunnel for measuring the gaseous losses of environmental chemicals from the soil/plant system under field-like conditions

Volatilization from treated areas is a major source of pesticide residues in air, fog, and rain. This may lead to long-range transport of pesticide residues to remote areas. Up to now most information on pesticide volatilization has come from laboratory experiments under controlled conditions. A new system has been designed and developed to measure the volatile losses of¹⁴C-labelled chemicals after application; the method compares with agricultural practice of treating soils or plants grown in lysimeters. Sensitive analytical methods guarantee a distinction between residues of unchanged pesticide, its metabolites or¹⁴CO₂ as a mineralization product released into the air.     

Synergistic interactions between edge and area effects in a heavily fragmented landscape

Both area and edge effects have a strong influence on ecological processes in fragmented landscapes, but there is little understanding of how these two factors might interact to exacerbate local species declines. To test for synergistic interactions between area and edge effects, we sampled a diverse beetle community in a heavily fragmented landscape in New Zealand. More than 35,000 beetles of approximately 900 species were sampled over large gradients in habitat area (10(-2) 10(6) ha) and distance from patch edge (2(0)-2(10) m from the forest edge into both the forest and adjacent matrix). Using a new approach to partition variance following an ordination analysis, we found that a synergistic interaction between habitat area and distance to edge was a more important determinant of patterns in beetle community composition than direct edge or area effects alone. The strength of edge effects in beetle-species composition increased nonlinearly with increasing fragment area. One important consequence of the synergy is that the slopes of species area (SA) curves constructed from habitat islands depend sensitively on the distance from edge at which sampling is conducted. Surprisingly, we found negative SA curves for communities sampled at intermediate distances from habitat edges, caused by differential edge responses of matrix- vs. forest-specialist species in fragments of increasing area. Our data indicate that distance to habitat edge has a consistently greater impact on beetle community composition than habitat area and that variation in the strength of edge effects may underlie many patterns that are superficially related to habitat area.     

Evaluation of solar powered water pumping system: the case study of three selected Abattoirs in Ibadan,Nigeria

In this paper, detailed and comprehensive analysis of the technical, environmental and economic benefits of providing adequate water supply using solar PV system for three selected abattoirs (Bodija, Akinyele and Iyana church abattoirs) in Ibadan are presented. First, an estimate of average daily water requirement for slaughtering and cleaning cattle is obtained for each of the abattoir. This was achieved through oral interviews conducted at the different abattoirs to arrive at a reliable estimate. Thereafter, the total water requirement, the water storage capacity and the electrical load requirement necessary for the sizing of solar PV system that will enhance the smooth operation of the abattoir are determined. Some of the key results revealed that the water requirements of the abattoirs are 208,780, 91,632 and 78,590 l/week, respectively. The most suitable submersible pump for the three abattoirs is 60GS50 (5hp, 60gallon/min Goulds series). The cost of pumping water and providing lighting for smooth operation of the abattoirs are $0.23, $0.21 and $0.19, respectively. The results also show that 16,300, 15,200 and 14,600 kg/yr of carbon dioxide as well as 46.37, 43.36 and 41.45 kg/yr of carbon monoxide could be avoided, respectively with the implementation of the project.     

Cultivation of freshwater microalgae in biodiesel wash water

Biodiesel wash water is a contaminating industrial effluent that must be treated prior to disposal. The use of this effluent as a low-cost alternative cultivation medium for microalgae could represent a viable supplementary treatment. We cultivated 11 microalgae species with potential use for biodiesel production to assess their growth capacities in biodiesel industrial washing waters. Only Monoraphidium contortum, Ankistrodesmus sp., Chlorococcum sp., and one unidentified Chlorophyceae species grew effectively in that effluent. M. contortum showed the highest growth capacity and had the second highest fatty acid content (267.9 mg g⁻¹ of DW), predominantly producing palmitic (20.9%), 7,10,13-hexadecatrienoic (14%), oleic (16.2%), linoleic (10.5%), and linolenic acids (23.2%). In the second phase of the experiment, the microalgae were cultivated in biodiesel wash water at 75% of its initial concentration as well as in WC (control) medium. After 21 days of cultivation, 25.8 and 7.2% of the effluent nitrate and phosphate were removed, respectively, and the chemical oxygen demand was diminished by 31.2%. These results suggest the possibility of cultivating biodiesel producing microalgae in industrial wash water effluents.

     

“One thing leads to another”—Commodities,linkages and industrial development

With a particular focus on low income economies in SSA, this paper addresses the nature and determinants of linkages from the commodities sectors and challenges the received view that enclave development is an inherent characteristic of resource extraction, particularly in the hard and energy commodities sectors. It argues that there has been a steady increase in linkage development and that there are significant opportunities for deepening this process. The opportunities may be greater for backward than for forward linkages, particularly in the minerals and energy sectors. In making this case, this Discussion Paper draws on the experience of high income countries which have resource intensive economic structures, the geographical specificity of many resources and the growing interest of large resource extracting firms in outsourcing the production of inputs which are outside of their core competences and in supporting local production of some inputs, it sets out a general model of linkage development which distinguishes between win–win and win–lose outcomes.     

Bioassessment tools in novel habitats: an evaluation of indices and sampling methods in low-gradient streams in California

Biomonitoring programs are often required to assess streams for which assessment tools have not been developed. For example, low-gradient streams (slope ≤1%) comprise 20–30% of stream miles in California and are of particular interest to watershed managers, yet most sampling methods and bioassessment indices in the state were developed in high-gradient systems. This study evaluated the performance of three sampling methods [targeted riffle composite (TRC), reach-wide benthos (RWB), and the margin–center–margin modification of RWB (MCM)] and two indices [the Southern California Index of Biotic Integrity (SCIBI) and the ratio of observed to expected taxa (O/E)] in low-gradient streams in California for application in this habitat type. Performance was evaluated in terms of efficacy (i.e., ability to collect enough individuals for index calculation), comparability (i.e., similarity of assemblages and index scores), sensitivity (i.e., responsiveness to disturbance), and precision (i.e., ability to detect small differences in index scores). The sampling methods varied in the degree to which they targeted macroinvertebrate-rich microhabitats, such as riffles and vegetated margins, which may be naturally scarce in low-gradient streams. The RWB method failed to collect sufficient numbers of individuals (i.e., ≥450) to calculate the SCIBI in 28 of 45 samples and often collected fewer than 100 individuals, suggesting it is inappropriate for low-gradient streams in California; failures for the other methods were less common (TRC, 16 samples; MCM, 11 samples). Within-site precision, measured as the minimum detectable difference (MDD) was poor but similar across methods for the SCIBI (ranging from 19 to 22). However, RWB had the lowest MDD for O/E scores (0.20 versus 0.24 and 0.28 for MCM and TRC, respectively). Mantel correlations showed that assemblages were more similar within sites among methods than within methods among sites, suggesting that the sampling methods were collecting similar assemblages of organisms. Statistically significant disagreements among methods were not detected, although O/E scores were higher for RWB samples than TRC. Index scores suggested impairment at all sites in the study. Although index scores did not respond strongly to several measurements of disturbance in the watershed, percent agriculture showed a significant, negative relationship with O/E scores.     

Physical and transport properties of aqueous amino alcohol solutions for CO2 capture from flue gas streams

Densities, viscosities and refractive indices of 4-diethylamino-2-butanol + water mixtures were measured over the entire concentration range of 0–1 mole fraction and temperature range from 298.15 to 343.15 K. Excess molar volumes, viscosity deviations, and molar refraction changes were calculated from the measurement results and correlated as a function of the mole fractions. Various models were used for correlation with the measured data. Out of these, the Redlich–Kister equation was the most suitable model that correlated best with experimental data. The percent absolute deviations obtained with this model were 0.03% for density, 0.88% for viscosity and 0.009% for refractive index.