Editing Nypa fruticans (section)

===Environmental Requirements:===
''Nypa'' is not a mangrove in the strict sense, as it does not
exploit truly littoral environments nor can it tolerate inundation with
undiluted sea-water for extended periods.
Casual observation of most ''Nypa'' populations will reveal the
limited adaptiveness of the palm. It occurs most commonly in areas
where brackish water occurs, extending far upstream into permanent
fresh-water areas where tidal-influenced water-level fluctuations are
able to carry and deposit the seeds. Secondarily, it can occur on low
flats and depressions near or far from the main water bodies, at the
base of eroding slopes and cliffs, or on sandy ridges or embankments.
It can tolerate infrequent inundation, so long as the substrate in
which it grows does not dehydrate for too long a period. The palm grows
as an undershrub, infrequently as a tree, or can dominate in mixed
forest. The species' 'ecological climax' appears to be in pure stands
on islets in the main channels or low flats on the inside of river
meanders where fine, rich silt deposits occur. These deposits are
replenished frequently by floods or wet season run-off from nearby
rivers.

Apart from temperature, the most critical environmental condition for
''Nypa'' is the percentage dilution of the sea-water by seaward
flowing fresh-water. ''Nypa'' does not require saline conditions at
all as the luxuriant stands in pure fresh-water indicate; the palm is
tolerant of an average low salinity, the salt-water tides being crucial
for seed dispersal and deposition of silt.

One of the authors (JD), during visitation to colonies in the Herbert
River delta, immediately north of Lucinda, Queensland, noted the
unexpected complete absence of seedlings and juvenile plants in the
populations. The uniformity of the size-class structure within these
colonies suggests that reproduction and expansion of these particular
colonies has been by clonal means rather than by recruitment of new
plants by seed.