This paper reports on possible effects of selective logging on vegetation structure and its consequences for two tenrec species in a dry forest in western Madagascar. On a small scale semi-mechanized logging of less than 10 m per ha alters forest structure significantly. However on a large scale most of these changes are smaller than the variation of forest structure due to natural causes. The most profound ecological effect of logging is a reduction in the number of woody species in the regenerating cohort of trees. Potential longterm consequences of this feature are discussed. Microhabitat variables influencing the habitat utilization of two tenrec species,Echinops telfairi andTenrec ecaudatus, were identified in an area of unlogged forest. The conclusions derived from this analysis were then tested in other parts of the forest which had been modified by selective logging. Logging of the extent described above slightly impairs habitats forE. telfairi but has no effect onT. ecaudatus. Though the latter species is hunted extensively in the logged areas, loggingper se does not threaten the survival of either species.

Energy saving is a significant feature to take in account in the choice of renewable energy technologies to use. This paper techno-economically investigates an excess heat recovery system that is proposed to be installed in a thermal cure center geothermal source for producing domestic hot water to be conveyed through piping to a nearby three star hotel located in Antsirabe Madagascar. For that purpose, the hotel hot water needs were determined by using an available online free code, called Solo, and the effectiveness-NTU method was used to size the plate heat exchanger to be used to recover the geothermal heat. The proposed hybrid geothermal solution performance was compared with that of hybrid solar energy water-heaters in terms of electricity consumption related to water temperature adjustment. It follows from comparison results that the proposed hybrid geothermal solution is more profitable and allows about 73.2 (%) of electric energy saving while it is 54.9 (%) for hybrid solar option. Besides, economic evaluation confirmed that the geothermal installation allows a shorter return on investment more favorably.Keywords: Heat recovery system, geothermal energy, heat exchanger, energy savings, domestic hot water production.Recent investigations tended to assess domestic hot water and energy production by using geothermal