A systems approach to the evaluation of natural resource management initiatives

Adopting a new paradigm for natural resource and environmental policy that emphasises continuous change, adaptation and learning demands a new approach to evaluation to enable improvements in the way these initiatives contribute to sustainable resource use. Evaluation is fundamental to identifying change, supporting an adaptive approach that is flexible enough to meet the challenge of change, and enabling learning at individual, community, institutional and policy levels. Based on a consideration of changing approaches to natural resource management (NRM) policy and observations and experiences in the practical assessment of on-the-ground initiatives, the authors develop a set of principles for evaluation in NRM that: (a) addresses evaluation from a systems perspective, (b) links objective to consequence, (c) considers the fundamental assumptions and hypotheses that underpin core policy or program objectives, (d) is grounded in the natural resource, policy/institutional, economic, socio-cultural and technological contexts of implementation in practice, (e) establishes practical and valid evaluation criteria by which change can be monitored and assessed, (f) involves methodological pluralism including both quantitative and qualitative methods to ensure rigour and comprehensiveness in assessment, and (g) integrates different disciplinary perspectives (i.e. social, economic, environmental, policy and technological). The paper develops a systems-based evaluation framework that incorporates these principles and also recognises the multiple levels and nested nature of NRM policy, namely: problem characterisation, policy formulation and intent, program logic, and on-ground implementation. Finally, we demonstrate its utility through application to three contrasting Australian case studies: a community-based Integrated Catchment Management policy implementation; a resource information delivery system; and the development of a Decision Support System.     

Wood Modification Effects on Weathering of HDPE-Based Wood Plastic Composites

The effects of weathering on the constituents of wood and polymer matrix behavior in wood plastic composites (WPCs) were investigated. WPCs were produced from pine, extractives-free pine, and pine holocellulose fibers (60%) together with HDPE (40%). These composites were subjected to xenon-arc accelerated and outside weathering for a total of 1200 h and 120 days, respectively. The color and chemical changes that occurred on the surface of the WPCs were analyzed using a set of analytical techniques. For pine and extractive-free pine filled composites, the results showed that the total color change, lightness, and oxidation increased, while the lignin content decreased. In addition, the weight average molecular weight (Mw) and number average molecular weight (Mn) of extracted HDPE decreased with an increase in exposure time of the composites. However, HDPE crystallinity increased with longer exposure time. Lightness of holocellulose-based WPC changed the least while the change in its HDPE crystallinity was not significant compared to the other composite types. Therefore, holocellulose-based WPC may be preferred for applications where color stability is of high priority.     

A perspective on the potential health risks of PBDEs

The polybrominated diphenylethers (PBDEs) are a class of chemicals widely used as flame retardants. Concentrations of PBDEs in some human and marine mammal populations are increasing. The toxicological endpoints of concern for environmental levels of PBDEs are likely to be thyroid hormone disruption, neurodevelopmental deficits and cancer. Unfortunately, the available toxicological evidence for these endpoints is surprisingly limited, given their widespread use, bioaccumulative potential, and structural similarity to thyroid hormones and polychlorinated biphenyls (PCBs). Available evidence suggests that the PBDE congeners likely to bioaccumulate (i.e., those observed in human tissues and other biota) have the propensity to disrupt thyroid hormones, cause neurobehavioral deficits and possibly cause cancer in laboratory animals. It is unclear whether current concentrations of PBDEs in human tissues would be expected to adversely impact human health. Since nearly all individuals are exposed to low levels of PBDEs, the potential health impacts also should include assessment at the population level. This paper summarizes the available toxicological evidence for PBDE-induced thyroid hormone disruption, neurodevelopmental deficits, and, for some congeners, cancer, and provides a perspective on the potential risks of the PBDEs for human health.     

Habitat as a mediator of mesopredator‐driven mammal extinction

A prevailing view in dryland systems is that mammals are constrained by the scarcity of fertile soils and primary productivity. An alternative view is that predation is a primary driver of mammal assemblages, especially in Australia, where 2 introduced mesopredators—feral cat (Felis catus) and red fox (Vulpes vulpes)—are responsible for severe declines of dryland mammals. We evaluated productivity and predation as drivers of native mammal assemblage structure in dryland Australia. We used new data from 90 sites to examine the divers of extant mammal species richness and reconstructed historic mammal assemblages to determine proportional loss of mammal species across broad habitat types (landform and vegetation communities). Predation was supported as a major driver of extant mammal richness, but its effect was strongly mediated by habitat. Areas that were rugged or had dense grass cover supported more mammal species than the more productive and topographically simple areas. Twelve species in the critical weight range (CWR) (35–5500 g) that is most vulnerable to mesopredator predation were extirpated from the continent's central region, and the severity of loss of species correlated negatively with ruggedness and positively with productivity. Based on previous studies, we expect that habitat mediates predation from red foxes and feral cats because it affects these species’ densities and foraging efficiency. Large areas of rugged terrain provided vital refuge for Australian dryland mammals, and we predict such areas will support the persistence of CWR species in the face of ongoing mammal declines elsewhere in Australia.     

Impact of water on CO2 capture by amino acid ionic liquids

The reversible capture of CO₂ from fossil-fueled industries and the absorption of CO₂ for natural-gas-sweetening purposes are industrial issues closely related to very important environmental, economical, and technological concerns. Biological amino acids can be used for task-specific ionic liquids for reversible CO₂ capture. Several groups have reported efficient and reversible CO₂ capture by such ionic liquids under rigorously dry conditions. However, we have observed that CO₂ capture by amino acid ionic liquids is hugely impacted by the presence of water. In addition, the amino acid anions appear to play only a transitory role in the CO₂ capture in the first minutes of exposure to a wet CO₂ stream. Here, we studied the interaction of two ionic liquids—tetramethylammonium glycinate ([N₁₁₁₁][Gly]) and tetraethylammonium prolinate ([N₂₂₂₂][Pro])—with CO₂ under wet conditions, by ¹³C-NMR. Results show that CO₂ is initially captured in a carbamate form by the amine-functionalized anions of these salts. This capture mode is unambiguously confirmed by a single-crystal X-ray study of the CO₂-ionic liquid complex. However, in solution, as additional CO₂ is added, the carbamate releases the covalently bound CO₂, and the CO₂ remaining in solution shifts in form to an equilibrium mixture of carbonate and bicarbonate. Indeed, when the amount of CO₂ present in the system exceeds about one-half mole per mole of ionic liquid present, the ionic liquid–carbamate complex is detected in only trace amounts, and the neutralized amino acids are readily identifiable by NMR.     

Comparing macroalgal food and habitat choice in sympatric, tube-building amphipods, Ampithoe lacertosa and Peramphithoe humeralis

For small tube-building amphipods that live on the algae they consume, food and habitat are tightly linked. This study compared two closely related amphipods to determine whether the species’ algal preferences are based on the food value of the algae or on some other aspect of their algal habitat. Ampithoe lacertosa and Peramphithoe humeralis are both abundant on Shannon Point beach (Anacortes, Washington, USA; 48°30.542′ N, 122°41.070′ W) but specialize on different algae. In observations and laboratory experiments conducted July–September 1997, 2007, and 2008, the two species exhibited markedly different choices of food and habitat when offered six common macroalgae. Ampithoe lacertosa ate all algae offered, but preferentially built tubes on the green alga Ulva lactuca. Survival was relatively low among juveniles maintained on single species diets, except when they were fed Mazzaella splendens. Conversely, P. humeralis consumed primarily the brown kelp Saccharina latissima, Alaria marginata, and Desmarestia ligulata and preferred those species for tube building. Juvenile P. humeralis could not survive on a diet of U. lactuca or M. splendens. While A. lacertosa builds simple, temporary tubes and relocates frequently, P. humeralis is a highly thigmotactic species that builds long-term, complex tubes on the alga it prefers to eat. Feeding and habitat preferences of the two species were not clearly linked to nitrogen content of the algae, C:N ratio, or toughness of the algal tissue. Instead, preferences of the species may be related to their mobility and the permanence of the tubes they build. Ampithoe lacertosa and P. humeralis also use different feeding strategies; the former appears to mix algae to produce a high-quality diet, while the latter is more selective and has a capacity for compensatory feeding. The species are abundant on the same protected rocky shores, but specialize on different algae for habitat and food. Results suggest that the nutritional requirements of these sympatric mesograzers differ considerably and even closely related species can exhibit divergent behavioral strategies.     

PICABUE: a methodological framework for the development of indicators of sustainable development

SUMMARY

Significant interest in the concept of sustainable development exists amongst scientists, planners, policy makers and the public, and considerable effort and expenditure is made or envisaged at local, national and international levels to promote a more sustainable society. Until ‘green accounting’ and similar systems are made available and are implemented, the sustainability indicator will be the most effective tool available for monitoring progress towards a more sustainable society. Sustainability indicators are already available but are characterized by a poor or absent theoretical underpinning. This paper addresses this problem by proposing a methodological framework that can be applied to the construction of indicators of sustainable development. In order to be consistent with widely accepted definitions of sustainable development, considerations relating to the measurement of quality of life and ecological integrity are central to the methodology. The methodological framework has relevance to a variety of spatial scales and to geographically diverse areas (urban or rural, developed or developing countries) so that a suite of sustainability indicators can be produced that is tailored to the needs and resources of the indicator user, but which remains rooted firmly in the fundamental principles of sustainable development.     

A critical analysis of ‘false-feeding’ behavior in a cooperatively breeding bird: disturbance effects,satiated nestlings or deception?

‘False feeding,’ where helpers arrive at nests with food but fail to provision the young, has been reported in several cooperative species. This and other potentially ‘deceptive’ behavior has been interpreted as indicating that helping may operate as a signal within such social groups. We critically examine these phenomena in the provisioning behavior of the bell miner Manorina melanophrys. Excessively close observation distances can artificially elevate the rate of false feeding in this (and other) species, but once this had been accounted for, there was little evidence for any ‘deceptive’ behavior by helpers or breeders. Natural and experimentally induced variation in the presence of a potential conspecific audience at the nest did not have any consistent influence upon the rate of false feeds, which was low at 7.94% of 6,880 nest visits. Instead, encountering unexpectedly low levels of brood demand provided a more parsimonious explanation for those visits where helpers failed to feed nestlings or ate the food themselves. Failure to completely transfer a load to nestlings was more likely when the load contained a high proportion of sticky lerp, indicating a simple prey-transfer problem. Finally, individuals that arrived at nests without prey were often members of neighboring breeding pairs, suggesting that these few non-feeding visits may instead involve an information-gathering function. We, therefore, suggest that future studies explicitly exclude the possibility of observer disturbance and all aspects of normal provisioning behavior before applying the terms ‘false feeding’ or ‘deceptive’ and inferring anything more than straightforward helping at the nest.