Land-cover change: quantification metrics for perforation using 2-D gap features.

Perforation or gap formation in a vegetation is a major process in landscape transformation. The occurrence of gaps profoundly alters the microclimatical conditions in a vegetation. A method is proposed to quantify perforation by using the three main 2-D characteristics of the gaps: area, number and boundary length.

The interior-to-edge breakpoint distance as a guideline for nature conservation policy.

A method is proposed to quantify disturbance impact on isolated habitats. For every landscape patch, the breakpoint distance, defined as the penetration distance for which equality of interior and edge habitat is observed, can be calculated. Disturbance with equal impact at all patch sides is assumed.

An analysis of the balance between root and shoot activity in Lolium perenne cv. Melvina. Effects of CO concentration and air temperature.

This study investigated the mechanisms which control the partitioning between roots and shoots in plants subjected to changes in environment. Two types of analyses were used: firstly, an examination of the cost and revenue associated with investment in different plant parts, and secondly, a test of the principle of functional equilibrium between roots and shoots, i.e.

Diurnal changes in the response of canopy photosynthetic rate to elevated CO2 in a coupled temperature-light environment.

The relative increase with elevated CO2 of canopy CO2 uptake rate (A), derived from continuous measurements during the day, was examined in full-cover vegetative Lolium perenne canopies after 17 days of regrowth. The stands were grown at ambient (358±50 μmol mol(-1)) and increased (626±50 μmol mol(-1)) CO2 concentration in sunlit growth chambers. Over the entire range of temperature and light conditions (which were strongly coupled and increased simultaneously), A was on average twice as large in high compared to ambient CO2.