Luis C. Rodriguez

An assessment of biomass for bioelectricity and biofuel, and for greenhouse gas emission reduction in Australia

We provide a quantitative assessment of the prospects for current and future biomass feedstocks for bioenergy in Australia, and associated estimates of the greenhouse gas (GHG) mitigation resulting from their use for production of biofuels or bioelectricity. National statistics were used to estimate current annual production from agricultural and forest production systems. Crop residues were estimated from grain production and harvest index. Wood production statistics and spatial modelling of forest growth were used to estimate quantities of pulpwood, in‐forest residues, and wood processing residues. Possible new production systems for oil from algae and the oil‐seed tree Pongamia pinnata, and of lignocellulosic biomass production from short‐rotation coppiced eucalypt crops were also examined. The following constraints were applied to biomass production and use: avoiding clearing of native vegetation; minimizing impacts on domestic food security; retaining a portion of agricultural and forest residues to protect soil; and minimizing the impact on local processing industries by diverting only the export fraction of grains or pulpwood to bioenergy. We estimated that it would be physically possible to produce 9.6 GL yr−1 of first generation ethanol from current production systems, replacing 6.5 GL yr−1 of gasoline or 34% of current gasoline usage. Current production systems for waste oil, tallow and canola seed could produce 0.9 GL yr−1 of biodiesel, or 4% of current diesel usage. Cellulosic biomass from current agricultural and forestry production systems (including biomass from hardwood plantations maturing by 2030) could produce 9.5 GL yr−1 of ethanol, replacing 6.4 GL yr−1 of gasoline, or ca. 34% of current consumption. The same lignocellulosic sources could instead provide 35 TWh yr−1, or ca. 15% of current electricity production. New production systems using algae and P. pinnata could produce ca. 3.96 and 0.9 GL biodiesel yr−1, respectively. In combination, they could replace 4.2 GL yr−1 of fossil diesel, or 23% of current usage. Short‐rotation coppiced eucalypt crops could provide 4.3 GL yr−1 of ethanol (2.9 GL yr−1 replacement, or 15% of current gasoline use) or 20.2 TWh yr−1 of electricity (9% of current generation). In total, first and second generation fuels from current and new production systems could mitigate 26 Mt CO2‐e, which is 38% of road transport emissions and 5% of the national emissions. Second generation fuels from current and new production systems could mitigate 13 Mt CO2‐e, which is 19% of road transport emissions and 2.4% of the national emissions lignocellulose from current and new production systems could mitigate 48 Mt CO2‐e, which is 28% of electricity emissions and 9% of the national emissions. There are challenging sustainability issues to consider in the production of large amounts of feedstock for bioenergy in Australia. Bioenergy production can have either positive or negative impacts. Although only the export fraction of grains and sugar was used to estimate first generation biofuels so that domestic food security was not affected, it would have an impact on food supply elsewhere. Environmental impacts on soil, water and biodiversity can be significant because of the large land base involved, and the likely use of intensive harvest regimes. These require careful management. Social impacts could be significant if there were to be large‐scale change in land use or management. In addition, although the economic considerations of feedstock production were not covered in this article, they will be the ultimate drivers of industry development. They are uncertain and are highly dependent on government policies (e.g. the price on carbon, GHG mitigation and renewable energy targets, mandates for renewable fuels), the price of fossil oil, and the scale of the industry.

PSEUDOREPLICATION AND ITS FREQUENCY IN OLFACTOMETRIC LABORATORY STUDIES

The evaluation of behavioral responses of an organism to a particular stimulus normally implies the design of a bioassay. Measurements of the response in a number of replicates are necessary to perform inferential statistics and therefore accept or reject a hypothesis about the effect of the stimulus on the behavior of the organism under study. In the present article, we address the importance of pseudoreplication in studies of chemical ecology, particularly in laboratory experiments on olfactory responses of insects to semiochemicals in olfactometers and wind tunnels. Pseudoreplication may be caused by lack of independence in the stimulus or the experimental device, the reutilization of test insects, or the use of groups of test insects, without adequate statistical analysis addressing such dependency. Each and all of the cases reviewed (N = 105) lacked information in at least one of the factors listed above; hence no cases could be said with certainty to be free of pseudoreplication. Forty-nine cases (46.7%) contained explicit information revealing that pseudoreplication existed in terms of one or more of the criteria listed above; in only three of these cases did the authors address statistically the stated dependence of the samples. Pseudoreplication due to different factors ranged from 2% to 30% of the cases, with an average of 13%. The most frequent sources of pseudoreplication were the reuse of the device and the use of groups of test insects. The analysis showed the low importance given to obtaining independent replicates in bioassays involving olfactometric responses of insects to semiochemicals.

Behavioural differences between Aphidius ervi populations from two tritrophic systems are due to phenotypic plasticity

The Palaeoarctic parasitoid Aphidius ervi Haliday (Hymenoptera, Aphidiidae) parasitises legume aphids in its region of origin. In Chile, it parasitises both legume and cereal aphids. This special situation was studied at two levels: (i) the host searching behaviour of A. ervi from two different tritrophic systems (Acyrthosiphon pisum on alfalfa and Sitobion avenae on wheat) was investigated in dual choice tests in a wind tunnel between odours from both A. pisum‐alfalfa host plant complex (HPC) and S. avenae‐wheat HPC, and (ii) the genetic structure of A. ervi populations from both sources using molecular markers. Responses of A. ervi females to volatile olfactory cues emanating from A. pisum‐alfalfa HPC and S. avenae‐wheat HPC were significantly higher towards the HPC on which they were reared during the last generation before experimentation, regardless of the origin of the parasitoid. As previously described for this parasitoid species, oviposition experience was also of major relevance in the preferences of female parasitoids. On the other hand, variation in mitochondrial DNA segments and RAPD‐PCR polymorphism using total DNA showed the absence of host‐based population structure and a high genetic homogeneity between these A. ervi populations. These results reject the possible existence of different host‐strains of this parasitoid in Chile.

A common view of the opportunities, challenges, and research actions for Pongamia in Australia.

Interest in biofuels is increasing in Australia due to volatile and rising oil prices, the need to reduce GHG emissions, and the recent introduction of a price on carbon. The seeds of Pongamia (Millettia pinnata) contain oils rich in C18:1 fatty acid, making it useful for the manufacture of biodiesel and other liquid fuels. Preliminary assessments of growth and seed yield in Australia have been promising. However, there is a pressing need to synthesise practical experience and existing fragmented research and to use this to underpin a well-founded and co-ordinated research strategy to support industry development, including better management of the risks associated with investment. This comprehensive review identifies opportunities for Pongamia in Australia and provides a snapshot of what is already known and the risks, uncertainties, and challenges based on published research, expert knowledge, and industry experience. We conclude that whilst there are major gaps in fundamental understanding of the limitations to growth of Pongamia in Australia, there is sufficient evidence indicating the potential of Pongamia as a feedstock for production of biofuel to warrant investment into a structured research and development program over the next decade. We identify ten critical research elements and propose a comprehensive research approach that links molecular level genetic research, paddock scale agronomic studies, landscape scale investigations, and new production systems and value chains into a range of aspects of sustainability.

Direction of dispersion of cochineal (Dactylopius coccus Costa) within the Americas

Dactylopius coccus has been used in Mexico and Peru as a source of natural dyes since pre-Columbian times. A phylogenetic analysis of the genus Dactylopius, and the disjoint distribution of D. coccus, suggest that the origin of D. coccus is South America and was introduced into North America by sea routes.

Diagnosis of typhoid fever by two serologic methods: Enzyme-linked immunosorbent assay of antilipopolysaccharide of Salmonella typhi antibodies and widal test

Serum samples from 85 patients with proven typhoid fever, 11 patients with p-typhoidal fever, 101 patients with febrile non-typhoidal, and 130 healthy subjects were tested for immunoglobulin G (IgG), IgA, and IgM antilipopolysaccharide (LPS) of Salmonella typhi antibodies by enzyme-linked immunosorbent assay (ELISA) and Widal test. The levels of all three classes of immunoglobulin anti-LPS of S. typhi were higher in typhoid patients than in healthy or febrile nontyphoidal groups; we selected various combinations between the three classes of immunoglobulin to obtain the best combination of sensitivity and specificity. The sum of the absorbance values obtained from the ELISA assay for IgG+IgA+IgM (sigma lgs) was the best choice for diagnostic utility for typhoid fever. We selected a positive test at a decision level of sigma lgs > or = 1.2 with a sensitivity of 94% and a specificity of 92% with a frequency of false negative of 5.9%. The frequency of false positives for healthy controls was 7.7% and, for the febrile nontyphoidal group, it was 7.9%. We also compared receiver (or relative) operating characteristic (ROC) curves for the diagnostic usefulness of the ELISA with that of the Widal test, whose merits and limitations, especially in endemic regions, are discussed. The ELISA assay was much more sensitive and specific than any combination of the Widal test, and hence it could be a useful tool for the serologic diagnosis of typhoidal fever with a single blood sample.

Adaptive changes of hepatic bile salt transport in a model of reversible interruption of the enterohepatic circulation in the rat

The reversibility and time course of the adaptive changes in hepatic bile salt transport related to modifications of the bile salt enterohepatic circulation and bile salt pool size have not been previously studied. For this reason a model of reversible interruption of entero-hepatic circulation was characterized in unrestrained rats, which allowed the study of changes in hepatic bile salt transport following bile salt pool depletion and subsequent restoration by either the de novo synthesis of bile acids or i.v. administration of exogenous taurocholate. Rats subjected to biliary drainage for 24 h through a transduodenal common bile duct cannula, followed by removal of the cannula and restoration of the enterohepatic circulation were studied at 24, 48 and 72 h. Neither light and electron microscopy examination nor plasma biochemical parameters showed evidence of necrosis, fibrosis, cholestasis or inflammatory changes. Maximum taurocholate secretory rate decreased to 50% following 24-h bile salt depletion. After restoration of the enterohepatic circulation maximum taurocholate secretory rate progressively increased to normal values at 72 h, following the normalization of the bile salt pool size, which had a similar composition compared with controls. The same effect was obtained when the native bile salt pool was substituted with exogenous taurocholate. Thus, adaptive down-regulation of hepatic bile salt transport capacity is a reversible process, related to restoration of entero-hepatic circulation and normalization of bile salt pool size.

Private farmers' compensation and viability of protected areas: the case of Nairobi National Park and Kitengela dispersal corridor

Nairobi National Park (NNP) is unable to incorporate the spatial and temporal dynamics of many migratory mammals that rely on the area as a dry season refuge because of its small size. During the wet season, wildlife must be able to migrate to the south into the Kitengela dispersal area. This area is privately owned and rapidly undergoing land-use change, which affects the structure and function of the dispersal corridors, jeopardising the ecological sustainability of the park. Private landholders in Kitengela incur most of the costs of keeping the dispersal areas open, but do not receive any compensation or revenue from benefits derived from tourism in the park. Here we present an analysis of the willingness-to-pay (WTP) for Nairobi and Kitengela residents for a new land management scheme in the dispersal area, in which local pastoralists leave their land open to wildlife and, by not engaging in fencing, land subdivision or poaching activities, receive monetary compensation for the incremental costs derived from use of their properties as a wildlife dispersal area. The results suggest that the aggregated financial support of urban residents might represent around

Community-based interventions for the use and conservation of animal genetic resources: the case of indigenous scavenger chicken production in Benin

1.2 million per year for 5 years. This amount exceeds the economic losses caused by wildlife in the dispersal area, and different financial schemes of fund investment and the prioritisation of conservation regions could be implemented to ensure payments and keep the dispersal corridors open in perpetuity.

Factores Bióticos y Concentración de Ácido Carmínico en la Cochinilla (Dactylopius coccus Costa) (Homoptera: Dactylopiidae)

Scavenging chicken production in Africa is important for the livelihood of the poor. In most countries, these low inputs, low output systems employ local breeds making use of the feeding resources available in the household. However, their replacement with introduced exotic breeds with higher productivities represents a risk for their conservation. Here, we present a simulation model to evaluate the impact of community-based interventions aiming to improve the profitability of local chicken breeds and promote their use and conservation. The results indicate that under the current conditions, farmers producing exotic chicken are able to sell more animals in a one year period; however the market price of local chicken makes their production more profitable. Vaccination campaigns significantly reduce the mortality rate of both breeds, having a positive effect on producers’ income but its impact on animal off-take is larger for exotic breeds, and the availability of feeding resources is the limiting factor as the flock size increases. The results of the intervention are positive in terms of increasing farmers’ income but do not clearly contribute to the conservation of indigenous breeds since after the vaccination campaign, the gap between the profitability of indigenous and exotic breeds is reduced. The simulation model indicates that under the current conditions, the conservation of indigenous chicken breeds in Benin is maintained by the existence of distinct niche markets with consumers able to pay higher prices for indigenous chicken. Policies for the conservation of chicken genetic resources in Benin are discussed.