Atmospheric CO2 concentrations have been increasing from ∼280 to 405 mmol mol−1 air from the preindustrial era until now. As this rise is a major driver for global warming and increasing variability in weather patterns, it is predicted that the frequency and duration of heat waves will continue to increase in many arable regions during this century. Lentil (Lens culinaris Medik.) is a cool‐season crop whose production has recently expanded into areas where it is subject to high temperature stress during pod filling (e.g., Australia). The objective of this experiment was to determine whether growth at elevated atmospheric CO2 concentrations (e[CO2], imposed by free‐air CO2 enrichment [FACE]) is able to compensate for the negative impact of a 3‐d heat wave event imposed at the flat pod stage on two lines of lentil. Grain yield under e[CO2] subjected to the heat wave were equivalent to grain yield under ambient without the heat wave event. The heat wave reduced grain yield by 33%, but this was not made more or less severe by e[CO2]. This reduction was attributed to a small decrease in aboveground biomass (6%) and a larger decrease in harvest index (16%) due to the heat wave event. The number of pods and grains per square meter were reduced by the heat wave (29–32%), whereas seed size was not affected. The effects of the heat wave during the event were evident on the foliar canopy temperature measured with an infrared thermometer, which increased by 6°C, and on the electron transport rate calculated from the quantum efficiency of photosystem II obtained with chlorophyll fluorescence measurements.

Elevated atmospheric carbon dioxide (CO 2 ) increases the instantaneous rate of photosynthesis in C 3 plants. With ample nutrients and water, this so-called 'CO 2 fertilization effect' generally leads to improved growth and production of many plant species that humans use as food. To determine whether increasing CO 2 could be beneficial to growth and yield of leafy Brassica vegetables, trials were established in a Free Air CO 2 Enrichment facility at Horsham, Australia using projected atmospheric CO 2 concentrations for the year 2050. The experiment measured the interacting effects of CO 2 (ambient CO 2 366 mmol/mol, elevated CO 2 562 mmol/mol), nitrogen (low/high) and Brassica rapa cultivars ( ) 2) on shoot growth under south-eastern Australian conditions. For cultivars 'Karate' and 'Chop Suey', significant interaction between elevated CO 2 and a high nitrogen treatment (196 kg/ha) increased the fresh weights of shoots.

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Web-spinning activity of Achaearanea tepidarorium (Koch) was observed in relation to amount of prior feeding, hours of food deprivation. and the number of flies (Drosophila melanogasters available in the animal's environment.Web spinning was positively related to the number of flies consumed in a 24-h period prior to testing, but did not vary significantly between 24 and 72 h of food deprivation. The amount of available food in the environment was positively related to web-spinning activity during a 48-h test period.