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Environmental envelopes are so named because they depict how parameters of interest are shaped by their
environment. They are boundary lines separating the observed world from an imaginary one. Quantile
regression enables us to determine their position objectively. Once located, the envelope enables us to
separate the range(s) of a determinant variable over which some variable of interest (relating to biological
performance, for example) is inevitably minimal from the range over which it is potentially at its maximum
value. Thus, in ecosystem management, which is critical to the sustainability of land use after mine closure,
we can identify ways in which plant cover and species diversity are affected by environmental variables such
as soil infiltrability even under conditions when other determinants are not kept constant. Recognising this
paradigm allows restoration ecologists to reduce their dependence on factorial field experiments for
discovering suitable methods of mine site rehabilitation. It is also applicable to discovering relationships
between abiotic variables in large data sets, such as that between routinely measured soil properties and
ones which are not readily determined but of which knowledge is critical in determining appropriate
restoration practices after mining. If combined with the diagnosis and recommendation integrated system
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