Incubation behaviour of the African jacana

In African jacanas all parental care is by males. The male's daytime attendance of the nest (= incubation constancy) averages 53% and is characterized by frequent, short ‘on’ and ‘off shifts in which he leaves the nest, on average, 35 times per day. Ambient temperatures affect both the incubation constancy and the duration of ‘on’ and ‘off’ shifts: on the coldest (x̄ = 22,9°C) of 4 days of variable weather in which egg and ambient temperatures were monitored together with the male's incubation behaviour, the incubation constancy was 70,9%, the eggs were unattended 28,1%, the ‘on’ shifts were long (x̄ = 22,5 min) and the ‘off’ shifts short (x̄ = 8,4 min). In contrast, on the hottest day (x̄ = 31,3°C) the eggs were unattended 56,5% of the day; they were incubated 6,9% and shaded 36,6%. Both ‘on’ (x̄ = 4,7 min) and ‘off’ (x̄ - 6,3 min) shifts were short. At night, when the eggs were constantly incubated, their temperature remained constant at 34,1 °C (SD = 0,4; n = 69) whereas in daytime their temperature ranged between a daily mean of 33,2–37,1°C (n = 4 days) and between extremes of 27,0–39,6°C. On a hot day (x̄ - 30,0°C) when the male was prevented from shading the test egg its temperature reached a lethal level (43,8°C) in 30 min. It is suggested that the high ambient temperatures prevailing in the African jacana's breeding range have facilitated the evolution of a uniparental care system in this species, but the males’ unusual incubation behaviour associated with high temperatures may also have led to the high clutch predation rate found in this species

Food consumption and pellet production in the black-shouldered kite, Elanus Caeruleus

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A growing city: agriculture and food security in the growing urban context

There are different kinds of growth, some of which are beneficial to life and some not. Sometimes it may look good on the surface but underneath the surface the roots are rotten and diseased. Physical growth is often related to food and resources, while mental health is related to stress. What can be found is that often different types of growth are in competition with one another. This is what is happening between our urban industrial systems and our food systems. They are competing for the same land at the expense of each other. This thesis delves into the various systems that affect urban growth and agricultural growth in the South African context. When looking at food security in the South African context, one finds that even though the country as a whole is food secure, a large portion of the population are still hungry and malnourished. One finds further that food insecurity is not an isolated problem – there are numerous issues of concern which share the same roots. These issues and concerns are in fact linked to the stresses that can affect wellbeing. Thus this thesis explores how physical health and mental wellbeing can come together in the production of a farm which heals a scar in the inner city landscape. Through considering the effects that urban conditions have on humans in contrast to the effects that the natural environment has on humans, this thesis addresses a design problem which seeks to unite the two extremes. It seeks to join the city with agriculture, allowing the city to continue expanding without losing arable land, and agriculture can improve the quality of the inner city. The design is formulated through response to context and climate, using biomimicry as a tool to create conditions conducive to life

Clearing your Desk! Software and Data Services for Collaborative Web Based GIS Analysis

David Tarboton is a professor at Utah State University. This presentation was given as part of the GIS Day@KU symposium on November 18, 2015. For more information about GIS Day@KU activities, please see http://www.gis.ku.edu/gisday/2015/.Platinum Sponsors: KU Department of Geography and Atmospheric Science; KU School of Business. Gold Sponsors: Bartlett & West; Kansas Biological Survey; KU Environmental Studies Program; KU Institute for Policy & Social Research; KU Libraries. Silver Sponsors: State of Kansas Data Access and Support Center (DASC). Bronze Sponsors: KU Center for Remote Sensing of Ice Sheets (CReSIS); TREKK Design Group, LLC; Wilson & Company, Engineers and Architects

Measurements and Modeling of Snow Energy Balance and Sublimation from Snow

Snow melt runoff is an important factor in runoff generation for most Utah rivers and a large contributer to Utah\u27s water supply and periodically flooding. The melting of snow is driven by fluxes of energy into the snow during warm periods. These consist of radiant energy from the sun and atmosphere, sensible and latent heat transfers due to turbulent energy exchanges at the snow surface and a relatively small ground flux from below. The turbulent energy exchanges are also responsible for sublimation from the snow surface, particularly in arid environments, and result in a loss of snow water equivalent available for melt. The cooling of the snowpack resulting for sublimation also delays the formation of melt runoff. This paper describes measurements and mathematical modeling done to quantify the sublimation from snow. Measurements were made at the Utah State University drainage and evapotranspiration research farm. I attempted to measure sublimation directly using weighing lysimeters. Energy balance components were measured, by measuring incoming and reflected radiation, wind, temperature and humidity gradients. An energy balance snowmelt model was tested against these measurements. The model uses a lumped representation of the snowpack with two state variables, namely , water equivalent and energy content relative to a reference state of water in the solid phase at 0 degrees Celcius. This energy content is used to determine snowpack average temperature or liquid fraction. The model is driven by inputs of air temperature, precipitation, wind speed, humidity and solar radiation. The model uses physically based calculations of radiative, sensible, latent and advective heat exchanges. An equilibrium parameterization of snow surface temperature accounts for differences between snow surface temperature and average snowpack temperature without having to introduce additional state variables. This is achieved by incorporating the snow surface thermal conductance, which with respect to heat flux is equivalent to stomatal and aerodynamic conductances used to calculate evapotranspiration from vegetation. Melt outflow is a function of the liquid fraction, using Darcy\u27s law. This allows the model to account for continued melt outflow even when the energy balance is negative. The purpose of the measurements presented here was to test the sublimation and turbulent exchange parameterizations in the model. However the weighing lysimeters used to measure sublimation suffered from temperature sensitive oscillations that mask short term sublimation measurements. I have therefore used the measured data to test the models capability to represent the overall seasonal accumulation and ablation of snow

The Source Hydrology of Severe Sustained Drought in th Southwestern U.S.

This paper considers the risk of drought and develops drough scenarios for use in the study of severe sustained drought in the Southwestern United States. The focus is on the Colorado River gbasin and regions to which Colorado River water is exported, especially southern California, which depends on water from the Colorado River as well as the four major rivers in northern California. Drought scenarios are developed using estimates of unimpaired historic streamflow as well as reconstructions of streamflow based on tree ring widths. Drought scenarios in the Colorado River are defined on the basis of annual flow at Lees Ferry. Possible spatial manifestations of the Colorado River drough scenarios for input into a Colorado River system simualation model are developed by disaggregating the Lees Ferry flow to monthly flows at twenty nine source locations required by the model. The risk, in terms of retun period, of the drough scenarios developed, is assessed using stochastic models applied to both the Colorado River basin and the comvined flow in four major California rivers. The risks of severe sustained drought occurring concurrently in the Colorado River basin and California is also assessed