'less negative effect' is correct and usable in written English.
It is typically used to describe something that is not as bad or damaging as it could be. For example, "The new policy has had a less negative effect on the company's profits than expected."
However, red wines certified by Demeter experience a positive or less negative effect from added SO2.
A less negative effect was found at the highest flue gas concentration when the algae were grown at 75 μmol m-2 s-1 PFD.
The conventional harvesting method applied at Usutu involved removing tree stems with bark from sites but not slash (Crous et al. 2007b) and is considered to have a less negative effect on site productivity than slash removal due to low nutrient content losses from stem wood (Mälkönen 1976; Olsson et al. 1996; Wall 2012).
Results on this context were also discordant; with a study showing that replacing only the coarse portion has less negative effect than replacing both portions (coarse and fine) (Hassan et al. 2000), while another study claims that replacing the fine portion with its equivalent RAP material results in better PCC mixes (Huang et al. 2006).
Sobering fact: Years of heavy drinking have a less negative effect on women, compared to men.
First, the food: Feed made from chickens and rabbits has a far less negative effect on the environment than feed from cud-chewing ruminants; I can easily swap out lamb for a more benign meat source.
Thus, less negative effects were associated with disinfection byproduct formation.
On the contrary, weather changes have relatively less negative effects on the RF signals.
Moreover, comparisons to native crayfish species showed that these had less negative effects on fish due to lower consumption and reproduction rates and population densities.
The variation of wind direction has less negative effects for VAWT because they do not need to be positioned into the wind direction.
However, if the major cause of some region's recent loss in net aboveground biomass change is global change-type drought, those soils with less drainage capacity should help buffer against increased evapotranspiration, resulting in less negative effects of global change-type drought on growth, mortality and net biomass change.
