Lessons from an Open Source Business

Creating a successful company is difficult; but creating a successful company, a successful open source project, and a successful ecosystem all at the same time is much more difficult. This article takes a retrospective look at some of the lessons we have learned in building BigBlueButton, an open source web conferencing system for distance education, and in building Blindside Networks, a company following the traditional business model of providing support and services to paying customers. Our main message is that the focus must be on creating a successful open source project first, for without it, no company in the ecosystem can flourish

An economic evaluation of tick line deregulation in Queensland

Rhipicephalus microplus, the cattle tick, is widely distributed across many tropical and subtropical regions of the world and has been identified as the most economically important species of tick across a number of countries. Quarantine boundaries currently limit the spread of the cattle tick into northern New South Wales, parts of South East Queensland, the central parts of the Northern Territory and northern parts of Western Australia. The Queensland tick line (or quarantine boundary) largely follows the 500mm rainfall isohyet until it reaches southern Queensland. As the cattle tick is unlikely to become endemic to regions receiving median rainfall less than 500mm per annum, the region most likely to be effected by a deregulation of the tick line is located in the south east corner of the State “inside” the 500mm isohyet but “outside” of the tick line. There are a number of strategies available to beef producers running susceptible cattle within the region impacted by a deregulation of the tick line. For example, they could: o choose to apply acaricides into the foreseeable future, o choose to breed tick resistance into their livestock and apply acaricides during the conversion period, o replace their susceptible breeding herds with tick resistant stock from within the tick endemic region, or o continue with susceptible livestock and implement sufficient quarantine and pest management strategies to reduce the risk of tick infestation to a negligible level The economic evaluation of these strategies indicates that the total costs of deregulation depend upon the type of response made by industry and the level of that response.Resource /Energy Economics and Policy,

The economics of phosphorus supplementation of beef cattle grazing northern Australian rangelands

Context: Phosphorus (P) deficiency occurs in beef cattle grazing many rangeland regions with low-P soils, including in northern Australia, and may severely reduce cattle productivity in terms of growth, reproductive efficiency and mortality. However, adoption of effective P supplementation by cattle producers in northern Australia is low. This is likely to be due to lack of information and understanding of the profitability of P supplementation where cattle are P-deficient. Aims: The profitability of P supplementation was evaluated for two dissimilar regions of northern Australia, namely (1) the Katherine region of the Northern Territory, and (2) the Fitzroy Natural Resource Management (NRM) region of central Queensland. Methods: Property-level, regionally relevant herd models were used to determine whole-of-business productivity and profitability over 30 years. The estimated costs and benefits of P supplementation were obtained from collation of experimental data and expert opinion of persons with extensive experience of the industry. The economic consequences of P supplementation at the property level were assessed by comparison of base production without P supplementation with the expected production of P-supplemented herds, and included the implementation phase and changes over time in herd structure. In the Katherine region, it was assumed that the entire cattle herd (breeders and growing cattle) grazed acutely P-deficient land types and the consequences of (1) no P supplementation, or P supplementation during (2) the dry season, or (3) both the wet and dry seasons (i.e. 3 scenarios) were evaluated. In the Fitzroy NRM region, it was assumed that only the breeders grazed P-deficient land types with three categories of P deficiency (marginal, deficient and acutely deficient), each with either (1) no P supplementation, or P supplementation during (2) the wet season, (3) the dry season, or (4) both the wet and dry seasons (i.e. 12 scenarios). Key results: In the Katherine region, year-round P supplementation of the entire cattle herd (7400 adult equivalents) grazing acutely P-deficient pasture resulted in a large increase in annual business profit (+AU$500 000). Supplementing with P (and N) only in the dry season increased annual business profit by +AU$200 000. In the Fitzroy NRM region, P supplementation during any season of the breeder herd grazing deficient or acutely P-deficient pastures increased profit by +AU$2400–AU$45 000/annum (total cattle herd 1500 adult equivalents). Importantly, P supplementation during the wet season-only resulted in the greatest increases in profit within each category of P deficiency, comprising +AU$5600, AU$6300 and AU$45 000 additional profit per annum for marginal, deficient and acutely P-deficient herds respectively. Conclusions: The large economic benefits of P supplementation for northern beef enterprises estimated in the present study substantiate the current industry recommendation that effective P supplementation is highly profitable when cattle are grazing P-deficient land types. Implications: The contradiction of large economic benefits of P supplementation and the generally low adoption rates by the cattle industry in northern Australia suggests a need for targeted research and extension to identify the specific constraints to adoption, including potential high initial capital costs

Seismic cycle and rheological effects on estimation of present-day slip rates for the Agua Blanca and San Miguel-Vallecitos faults, northern Baja California, Mexico

Geodesy can be used to infer long-term fault slip rates, assuming a model for crust and upper mantle rheology. We examine the sensitivity of fault slip rate estimates to assumed rheology for the Agua Blanca and San Miguel-Vallecitos faults in northern Baja California, Mexico, part of the Pacific–North America plate boundary zone. The Agua Blanca fault is seismically quiet, but offset alluvial fans indicate young activity. Current seismicity is confined to the nearby San Miguel-Vallecitos fault, a small offset fault better aligned with plate motion. GPS measurements between 1993 and 1998 suggest that both faults are active, with a combined slip rate of 4–8 mm yr. regardless of rheological model. However, slip rate estimates for the individual faults are sensitive to assumed rheology. Elastic half-space models yield 2–3 mm yr. for the Agua Blanca fault, and somewhat faster rates for the San Miguel-Vallecitos fault, 2–4 mm yr., with uncertainties of about 1 mm yr. Models incorporating viscoelastic rheology and seismic cycle effects suggest a faster slip rate for the Agua Blanca fault, 6 ± 1 mm yr, and a slower rate for the San Miguel-Vallecitos fault, 1 ± 1 mm yr, in better agreement with geological data, but these rates are sensitive to assumed rheology. Numerical simulations with a finite element model suggest that for similar rheological and friction conditions, slip on the San Miguel-Vallecitos fault should be favored due to better alignment with plate motion. Long-term faulting processes in the larger offset Agua Blanca fault may have lowered slip resistance, allowing accommodation of motion despite misalignment with plate motion

New kinematic models for Pacific‐North America Motion from 3 Ma to Present, II: Evidence for a “Baja California Shear Zone”

We use new models for present‐day Pacific‐North America motion to evaluate the tectonics of offshore regions west of the Californias. Vandenburg in coastal Alta California moves at the Pacific plate velocity within uncertainties (∼1 mm/yr) after correcting for strain accumulation on the San Andreas and San Gregorio‐Hosgri faults with a model that includes a viscoelastic lower crust. Modeled and measured velocities at coastal sites in Baja California south of the Agua Blanca fault, a region that most previous models consider Pacific plate, differ by 3–8 mm/yr, with coastal sites moving slower that the Pacific plate. We interpret these discrepancies in terms of strain accumulation on known on‐shore faults, combined with right lateral slip at a rate of 3–4 mm/yr on additional faults offshore peninsular Baja California in the Pacific. Offshore seismicity, offset Quaternary features along the west coast of Baja California, and a discrepancy between the magnetically determined spreading rate in the Gulf Rise and the total plate rate from a geological model provide independent evidence for a “Baja California shear zone.

Final report on project SP1210: Lowland peatland systems in England and Wales – evaluating greenhouse gas fluxes and carbon balances

Lowland peatlands represent one of the most carbon-rich ecosystems in the UK. As a result of widespread habitat modification and drainage to support agriculture and peat extraction, they have been converted from natural carbon sinks into major carbon sources, and are now amongst the largest sources of greenhouse gas (GHG) emissions from the UK land-use sector. Despite this, they have previously received relatively little policy attention, and measures to reduce GHG emissions either through re-wetting and restoration or improved management of agricultural land remain at a relatively early stage. In part, this has stemmed from a lack of reliable measurements on the carbon and GHG balance of UK lowland peatlands. This project aimed to address this evidence gap via an unprecedented programme of consistent, multi year field measurements at a total of 15 lowland peatland sites in England and Wales, ranging from conservation managed ‘near-natural’ ecosystems to intensively managed agricultural and extraction sites. The use of standardised measurement and data analysis protocols allowed the magnitude of GHG emissions and removals by peatlands to be quantified across this heterogeneous data set, and for controlling factors to be identified. The network of seven flux towers established during the project is believed to be unique on peatlands globally, and has provided new insights into the processes the control GHG fluxes in lowland peatlands. The work undertaken is intended to support the future development and implementation of agricultural management and restoration measures aimed at reducing the contribution of these important ecosystems to UK GHG emissions