Givnish and Vermelj (1976) observed that leaves optimize their size (thus mass) for the conditions. This may be interpreted as meaning that they maximize their free-energy content. The larger the leaves the higher their respiration and evapo-transpiration, but the more solar radiation they can capture. Deciduous forests in moist climates have a leaf-area index (LAI) of about 6 (see also Section 2.4). Such an index can be predicted from the hypothesis of highest possible leaf size, resulting from the trade-off between having leaves of a given size versus maintaining leaves of a given size (Givnish and Vermelj, 1976). Size of leaves in a given environment depends on the solar radiation and humidity regime, andwhile, for example, Sun and shade leaves on the same plant would not have equal exergy contents, and in a general way leaf size and LAI relationships are consistent with the hypothesis of maximum exergy storage.
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Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.