9 research outputs found
Fog as a Fresh-Water Resource: Overview and Perspectives
The collection of fog water is a simple and sustainable technology to obtain fresh water for afforestation, gardening, and as a drinking water source for human and animal consumption. In regions where fresh water is sparse and fog frequently occurs, it is feasible to set up a passive mesh system for fog water collection. The mesh is directly exposed to the atmosphere, and the foggy air is pushed through the mesh by the wind. Fog droplets are deposited on the mesh, combine to form larger droplets, and run down passing into a storage tank. Fog water collection rates vary dramatically from site to site but yearly averages from 3 to 10Â l m(â2) of mesh per day are typical of operational projects. The scope of this article is to review fog collection projects worldwide, to analyze factors of success, and to evaluate the prospects of this technology
The effect of fire severity on first-year seedling establishment in a Pinus canariensis forest on Tenerife, Canary Islands
The Canarian pine (Pinus canariensis) exhibits
a striking combination of high adult resistance to fire and
intermediate serotiny. Hence, the study of its post-fire
regeneration can support valuable new insights about
functional adaptations to fire. Here, we analyse the firstyear
seedling establishment after fire in a P. canariensis
forest on the northern slope of Tenerife, Canary Islands.
The effects of fire severity and other explanatory variables
on the seedling density recorded 9 months after fire were
examined. We detected a clear unimodal relationship
between seedling density and fire severity, with maximum
regeneration associated with intermediate fire severity and
no regeneration associated with very high crown damage.
The results suggested that high severity fires may have
caused the partial destruction of the aerial seed bank and/or
the creation of unfavourable seedbed conditions for germination
and seedling emergence. The density of large
pine trees, reflecting seed availability, was the second most
important factor explaining the distribution of seedlings.
Cover of scorched needle litter on the ground correlated
strongly and positively with pine seedling density and
negatively with fire severity. The complete lack of regeneration
at sites most strongly affected by fire does not
represent a major threat for the stand recovery of the
Canarian pine, due to the very high tree resistance to fire
and the tremendous capacity of the Canarian pine to
resprout after fire. The observed very high seedling densities
at sites with intermediate fire impacts can probably be
related to both the complete liberation of the seed bank
(including seeds stored in serotinous cones) and favourable
micro-environmental conditions for seed germination and
seedling establishment