The disappearance of muntjac (Muntiacus reevesi) and roe deer (Capreolus capreolus) pellet groups in a pine forest of lowland England

Reliable knowledge of the disappearance rate of faecal pellets is essential for converting pellet density to deer density when using standing-crop pellet-group counts. Disappearance of muntjac and roe deer pellet groups was monitored in four growth stages of a pine forest of lowland England over a 15-month period. Time to disappearance of the pellet groups (days) of both species significantly differed between habitats and months; it was shorter in late summer to early autumn and in habitats with more ground vegetation. Muntjac pellet groups disappeared more quickly than roe deer pellet groups. Time to disappearance of roe deer pellet groups was negatively correlated with air and grass temperature in pre-thicket and pre-fell habitats, while time to disappearance of muntjac pellet groups was negatively correlated with frequency of rainfall and positively correlated with the run of wind (air passage over a site within a 24-h period measured in km) in pre-thicket habitats. It is the time of the standing-crop pellet-group counts and the disappearance rate of pellet groups deposited in different months and habitats that determine the appropriate method for conversion of pellet-group density to deer density

A global assessment of the effects of climate policy on the impacts of climate change

This study presents the first global-scale multi-sectoral regional assessment of the magnitude and uncertainty in the impacts of climate change avoided by emissions policies. The analysis suggests that the most stringent emissions policy considered here – which gives a 50% chance of remaining below a 2oC temperature rise target - reduces impacts by 20-65% by 2100 relative to a ‘business-as-usual’ pathway (A1B) which reaches 4oC, and can delay impacts by several decades. Effects vary between sector and region, and there are few noticeable effects of mitigation policy by 2030. The impacts avoided by 2100 are more strongly influenced by the date and level at which emissions peak than the rate of decline of emissions, with an earlier and lower emissions peak avoiding more impacts. The estimated proportion of impacts avoided at the global scale is relatively robust despite uncertainty in the spatial pattern of climate change, but the absolute amount of avoided impacts is considerably more variable and therefore uncertain

The effect of short-term flooding on the sap flow, gas exchange and hydraulic conductivity of young apricot trees

The effect of short-term flooding was examined in 2-year-old apricot trees (Prunus armeniaca cv. Búlida). Six apricot trees of similar appearance were submitted to two treatments: three were irrigated daily, while the others were flooded for a period of 50 h by submerging the pots in plastic water tanks. The trees were removed from the water, drained and then placed in the same conditions as the control plants. A decrease in transpiration in the flooded trees with respect to the control plants was evident. The daily pattern of soil O2 concentration and plant hydraulic resistance followed a similar trend during the flooding. However, this relationship was not maintained throughout the experiment, since the O2 values increased rapidly when the waterlogging ceased, while plant hydraulic resistance only recovered at the end of the experiment when the original root system, damaged by flooded conditions, was replaced with new roots. In flooded trees, the midday leaf water potential decreased progressively from the beginning of flooding, but gradually recovered when the waterlogging ceased. Leaf conductance values of treated plants were slow to recover, reaching values of the control plants 8 days after the leaf water potential had recovered. The close relationship observed during most of the experiment between the leaf water parameters, leaf conductance and plant hydraulic conductance indicate that hydraulic messages are likely to play a dominant role in co-ordinating the observed responses of the shoot.The study was supported by two projects: Riego inteligente para un manejo sostenible en frutales (CYCIT-AGL2000-0387-CO5-O4) and Desarrollo de un equipo autónomo para la medición de caudal de savia en plantas leñosas (PETRI-95-0693-01).Peer reviewe