Growth and population dynamics of crayfish Paranephrops planifrons in streams within native forest and pastoral land uses

Population dynamics of crayfish (Paranephrops planifrons White) in streams draining native forest and pastoral catchments, Waikato, New Zealand, were investigated from September 1996 to July 1998. Crayfish densities were generally greater in native forest streams because of high recruitment over summer, but varied greatly between streams in both land uses. Peak densities in summer were 9 crayfish m-2 in native forest and 6 crayfish m-2 in pasture streams, but peak biomass in summer was much greater in pasture streams. Mark-recapture data showed that crayfish, particularly juveniles, in pasture streams grew faster than in native forest streams, through both greater moult frequency and larger moult increments. Females reached reproductive size at c. 20 mm orbit-carapace length (OCL) after their first year in pasture streams, but after 2 years in native forest streams. Annual degree days >10°C appeared to explain the differences in the timing of life cycles. Estimates of annual crayfish production (range = 0.8-3.4 g dry weight m-2 year-1) were similar in both land uses, and P/B ratios were between 0.95 and 1.2. Despite deforestation and conversion to pasture, crayfish in these Waikato hill-country streams have maintained similar levels of annual production to those in native forest streams, although juvenile growth rates have increased and longevity has decreased

The Divine Pedagogy: Theological Explorations of Intelligent Extraterrestrial Life

Abstract Speculation regarding the plurality of worlds and its closely related subject of the existence of intelligent extraterrestrials has remained an important question for Christian theology from antiquity until the modern age. Advancements in space science of the twentieth and twenty-first centuries have revealed a vast universe containing trillions of galaxies, as well as new discoveries of exoplanets, which has provided an unprecedented greater context and perspective in consideration of the place of humanity, possible intelligent extraterrestrials, and the role of divinity in relation to creatures. This has led to increased importance to the question regarding the relation of extraterrestrials to the Christian doctrines of the Incarnation and Redemption, which for centuries has evaded theological resolution. Historically, a handful of theologians have given limited attention to the question of the redemption of possible extraterrestrials, and since early Christianity have proposed several possible solutions, which are categorized according to four types: an exclusive view, asserting a single divine incarnation and salvation provided solely for humans on Earth, without access to potential extraterrestrials; an inclusive view, which includes extraterrestrials within the redemptive sacrifice of Christ on Earth; a multiple view, which posits multiple incarnations of the Logos in extraterrestrial civilizations for their redemption; and a varied view, which argues for the total freedom of divine plans in the salvation of intelligent extraterrestrials. This thesis will argue for the varied view in consideration of intelligent extraterrestrials, which allows for the ‘omni-properties’ of divinity in the creation and redemption of intelligent creatures according to divine prerogative. Examination of the history of developments in scientific and theological thought on extraterrestrials, from antiquity to the twenty-first century will demonstrate a consistent pattern of theological formulations of extraterrestrials and their relation to Christian Christology and Soteriology. In the discussion of this subject, an extraterrestrial ‘anthropology’, psychology, morphological possibilities, sociological compositions, extraterrestrial religions, implications of contact, and a ‘divine pedagogy’ of potential modalities of extra-mundus supernatural presence and action will be considered

Description and performance of a digital mobile satellite terminal

A major goal of the Mobile Satellite Experiment (MSAT-X) program at the Jet Propulsion Lab (JPL) is the development of an advanced digital terminal for use in land mobile satellite communication. The terminal has been developed to minimize the risk of applying advanced technologies to future commercial mobile satellite systems (MSS). Testing with existing L band satellites was performed in fixed, land mobile and aeronautical mobile environments. JPL's development and tests of its mobile terminal have demonstrated the viability of narrowband digital voice communications in a land mobile environment through geostationary satellites. This paper provides a consolidated description of the terminal architecture and the performance of its individual elements

Evaluating techniques for sampling stream crayfish (paranephrops planifrons)

We evaluated several capture and analysis techniques for estimating abundance and size structure of freshwater crayfish (Paranephrops planifrons) (koura) from a forested North Island, New Zealand stream to provide a methodological basis for future population studies. Direct observation at night and collecting with baited traps were not considered useful. A quadrat sampler was highly biased toward collecting small individuals. Handnetting at night and estimating abundances using the depletion method were not as efficient as handnetting on different dates and analysing by a mark-recapture technique. Electrofishing was effective in collecting koura from different habitats and resulted in the highest abundance estimates, and mark-recapture estimates appeared to be more precise than depletion estimates, especially if multiple recaptures were made. Handnetting captured more large crayfish relative to electrofishing or the quadrat sampler

Climate change mitigation for agriculture: water quality benefits and costs

New Zealand is unique in that half of its national greenhouse gas (GHG) inventory derives from agriculture--predominantly as methane (CH4) and nitrous oxide (N2O), in a 2:1 ratio. The remaining GHG emissions predominantly comprise carbon dioxide (CO2) deriving  from  energy  and  industry  sources.  Proposed strategies to  mitigate  emissions  of  CH4  and  N2O  from  pastoral  agriculture in New Zealand are: (1) utilising extensive and riparian afforestation of pasture to achieve CO2 uptake (carbon sequestration); (2) management of nitrogen through budgeting and/or the use of nitrification inhibitors, and minimising soil anoxia to reduce N2O emissions; and (3) utilisation of alternative waste treatment technologies to minimise emissions of CH4. These mitigation measures have associated co-benefits and co-costs (disadvantages) for rivers, streams and lakes because they affect land use, runoff loads, and receiving water and habitat quality. Extensive afforestation results in lower specific yields (exports) of nitrogen (N), phosphorus (P), suspended sediment (SS) and faecal matter and also has benefits for stream habitat quality by improving stream temperature, dissolved oxygen and pH regimes through greater shading, and the supply of woody debris and terrestrial food resources. Riparian afforestation does not achieve the same reductions in exports as extensive afforestation but can achieve reductions in concentrations of N, P, SS and faecal organisms. Extensive afforestation of pasture leads to reduced water yields and stream flows. Both afforestation measures produce intermittent disturbances to waterways during forestry operations (logging and thinning), resulting in sediment release from channel re-stabilisation and localised flooding, including formation of debris dams at culverts. Soil and fertiliser management benefits aquatic ecosystems by reducing N exports but the use of nitrification inhibitors, viz. dicyandiamide (DCD), to achieve this may under some circumstances impair wetland function to intercept and remove nitrate from drainage water, or even add to the overall N loading to waterways. DCD is water soluble and degrades rapidly in warm soil conditions. The recommended application rate of 10 kg DCD/ha corresponds to 6 kg N/ha and may be exceeded in warm climates. Of the N2O produced by agricultural systems, approximately 30% is emitted from indirect sources, which are waterways draining agriculture. It is important therefore to focus strategies for managing N inputs to agricultural systems generally to reduce inputs to wetlands and streams where these might be reduced to N2O. Waste management options include utilising the CH4 resource produced in farm waste treatment ponds as a source of energy, with conversion to CO2 via combustion achieving a 21-fold reduction in GHG emissions. Both of these have co-benefits for waterways as a result of reduced loadings. A conceptual model derived showing the linkages between key land management practices for greenhouse gas mitigation and key waterway values and ecosystem attributes is derived to aid resource managers making decisions affecting waterways and atmospheric GHG emissions

Satellite university campuses and economic development in peripheral regions

Satellite university campuses – whereby established universities decentralise part of their activities, often to areas previously lacking a university – contribute to the diversification of university systems. While satellite campuses, due to their small scale and limited resources, might perform some activities less efficiently than their larger parent universities, we argue that they are uniquely placed to serve the needs of their localities. Based on the case of a satellite campus in North-West Italy, we show that: (i) the campus’ main contribution lies in widening access to higher education to residents who would not attend university in the absence of local provision; (ii) the campus contributes to local development also through research and business and community engagement, and by stimulating local demand for knowledge-intensive services; (iii) research and engagement are more effective for local development where local firms possess relevant absorptive capacity and where there is a favourable institutional framework

Alveolar proteins stabilize cortical microtubules in Toxoplasma gondii

Single-celled protists use elaborate cytoskeletal structures, including arrays of microtubules at the cell periphery, to maintain polarity and rigidity. The obligate intracellular parasite Toxoplasma gondii has unusually stable cortical microtubules beneath the alveoli, a network of flattened membrane vesicles that subtends the plasmalemma. However, anchoring of microtubules along alveolar membranes is not understood. Here, we show that GAPM1a, an integral membrane protein of the alveoli, plays a role in maintaining microtubule stability. Degradation of GAPM1a causes cortical microtubule disorganisation and subsequent depo-lymerisation. These changes in the cytoskeleton lead to parasites becoming shorter and rounder, which is accompanied by a decrease in cellular volume. Extended GAPM1a depletion leads to severe defects in division, reminiscent of the effect of disrupting other alveolar proteins. We suggest that GAPM proteins link the cortical microtubules to the alveoli and are required to maintain the shape and rigidity of apicomplexan zoites

Omnivoria e repartição de recursos em águas pobres em nutrientes da Bacia do Rio Negro

Amazonian biodiversity is notorious, this is also valid for the fauna of the mineral-deficient waters of the Rio Negro System. Some 25 years of research on the benthic fauna of Central Amazonian streams resulted in species-rich foodwebs with a high degree of omnivory within dense animal communities. To exemplify the taxonomic range of omnivorous consumers, the detailed resource spectra of 18 consumer species, including Protozoa (2 species), Platyhelminthes (1 species), insects (2 species), fish (6 species) and shrimps (Decapoda, 7 species), associated primarily with the benthic habitats of Rio Negro tributaries, are presented. Special features of omnivory are characterized, and the importance of litter-decomposing fungi as essential energy input into the foodwebs is documented. It is shown that general omnivory -diverse omnivore consumers sharing most of the resource types- is a prevalent feature. The relevance of this general omnivory for the maintenance of biodiversity is discussed.A biodiversidade do Amazonas é notório e isto também é válido para as águas pobres em nutrientes da bacia do Rio Negro. Uma pesquisa de 25 anos da fauna béntica de igarapés da Amazônia Central resultou em redes alimentares caraterizadas por alta diversidade de espécies, por intensa omnivoria e por alta densidade populacional. Para demonstrar a generalidade taxonômica de omnivoria no bentos dos igarapés, são apresentados as listas de presas / recursos de 18 espécies de consumidores, sendo Protozoa (2 epécies), Platyhelminthes (1 espécie), insetos (2 espécies), peixes (6 espécies) e camarões (Decapoda, 7 espécies). Diferentes categorias de omnivoria são apresentados, e a importância de fungos decompositores da liteira submersa como input básico de energia nas redes alimentares é demonstrada. É prevalente a omnivoria geral, sendo que as diferentes espécies omnívoros estão utilizando os mesmos recursos. Considera- se a relevância desta omnivoria geral para a manutenção da biodiversidade