The north–south coordinate was a strong explanatory variable both for species numbers and species composition. This is not surprising because, compared to the sites north of the lake, the area around lake Mälaren is both climatically favourable (Raab and Vedin 1995) and has a high density of sites with old trees. Mälaren has been identified as a diversity hot-spot for saproxylic beetles (Ehnström and Waldén 1986), with the western part of Mälaren regarded as being especially species-rich. This was only weakly supported by the results of the present study, as the variable RT90E (west–east
coordinate) had low explanatory power. Practical implications The high conservation value of parks for saproxylic insects shown in this study is dependent on the retention of old trees. Thus, the total rejuvenation of trees, which is considered in some parks, would be fatal KU55933 molecular weight to the resident fauna. However, all trees will sooner or later die, or they have to be removed for safety or aesthetic reasons. If they individually and continuously are replaced when they die there will be a continuous supply of new trees growing into the ancient-tree age class which in turn means a continuous supply of suitable habitat for the saproxylic insects. On a short term a good measure is to retain trees, or parts of trees, that are cut Verubecestat cost or fallen in a “tree-graveyard”
situated in a remote part of the park, where it does not conflict with the aesthetic values. Such graveyards is both a chance for insects to finalise their development and a habitat patch that can be colonised (Aulén and Franc
2008). However, compared to the management aiming at a long term continuous supply of old trees, this is of minor importance, both {Selleck Anti-infection Compound Library|Selleck Antiinfection Compound Library|Selleck Anti-infection Compound Library|Selleck Antiinfection Compound Library|Selleckchem Anti-infection Compound Library|Selleckchem Antiinfection Compound Library|Selleckchem Anti-infection Compound Library|Selleckchem Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|Anti-infection Compound Library|Antiinfection Compound Library|buy Anti-infection Compound Library|Anti-infection Compound Library ic50|Anti-infection Compound Library price|Anti-infection Compound Library cost|Anti-infection Compound Library solubility dmso|Anti-infection Compound Library purchase|Anti-infection Compound Library manufacturer|Anti-infection Compound Library research buy|Anti-infection Compound Library order|Anti-infection Compound Library mouse|Anti-infection Compound Library chemical structure|Anti-infection Compound Library mw|Anti-infection Compound Library molecular weight|Anti-infection Compound Library datasheet|Anti-infection Compound Library supplier|Anti-infection Compound Library in vitro|Anti-infection Compound Library cell line|Anti-infection Compound Library concentration|Anti-infection Compound Library nmr|Anti-infection Compound Library in vivo|Anti-infection Compound Library clinical trial|Anti-infection Compound Library cell assay|Anti-infection Compound Library screening|Anti-infection Compound Library high throughput|buy Antiinfection Compound Library|Antiinfection Compound Library ic50|Antiinfection Compound Library price|Antiinfection Compound Library cost|Antiinfection Compound Library solubility dmso|Antiinfection Compound Library purchase|Antiinfection Compound Library manufacturer|Antiinfection Compound Library research buy|Antiinfection Compound Library order|Antiinfection Compound Library chemical structure|Antiinfection Compound Library datasheet|Antiinfection Compound Library supplier|Antiinfection Compound Library in vitro|Antiinfection Compound Library cell line|Antiinfection Compound Library concentration|Antiinfection Compound Library clinical trial|Antiinfection Compound Library cell assay|Antiinfection Compound Library screening|Antiinfection Compound Library high throughput|Anti-infection Compound high throughput screening| because its’ short term effect and because most of the valuable contributions to the graveyard emanate from the old trees. As almost all lime trees in ifoxetine parks, and many lime trees in the more natural sites, were originally pollarded, they are at risk of breaking apart when the shoots from the last pollarding are allowed to grow into large trees. This was observed on several of the sites in this study. The risk of breakage is especially great in re-grown sites where the closer canopy gives less light to the trees, which in turn decreases the production of carbohydrates needed for building a stable trunk. For keeping these old trees alive it is important to continue pollarding. However, old trees that has not been managed for a long time need careful treatment when management is resumed (Slotte 1997; Wisenfield 1995). A strong reduction of the crown by cutting all large branches may be fatal. As pollarding is an expensive measure, it is important that it should only be done on sites where there is the potential to retain the associated fauna and flora, i.e. where one can forecast a continuous supply of old trees in the future. Most of the parks in the present study do have this potential due to the continuous replacement of trees that die.