Sustainable Land Use(was Mulches)

>  An argument surely I would have thought for some restraint in drawing
>  off so much water for those (non-native) lawns. >>
> 
> Hi, Moira.  Thanks for your insightful comments.  Of course people should
> practice good water use practices in our arid climate.  The truth is,
> however, that something like 90% of California's water supply goes to
> irrigate farmland, so even a sea change in urban water use practices would
> have only a small effect on overall supplies.  Drip-irrigation for
> agriculture has proven to be something of a double-edged sword.  Yes, it
> would help to conserve water if it were only used to replace flood- and/or
> sprinkler-irrigation in the areas where those are practiced.  Unfortunately,
> where they can be practiced successfully (usually on flat farmland), those
> methods continue to be used because they are cheaper.  The introduction of
> drip-irrigation has instead had the effect of rapidly expanding the amount of
> irrigated farmland, as areas (usually hilly) once considered suitable only
> for grazing are found to grow vineyards and orchards quite successfully.  I'm
> not sure what the solution is, but I think I could be a rabid
> environmentalist without too much provocation!
> 
Hi Kurt
Sounds like yet another example of people pursuing their own agendas
with no regard for the health and welfare of the local ecosystem. One
wonders how long it will be before some disaster overtakes the area.
There are examples of this all over the world. In Africa, for instance,
the spread of the Sahara has undoubtedly been hastened by overgrazing
and the turning of almost all the tree cover into firewood, and this
desertification is now taking place in a good deal of East Africa as
well.

Here in NZ farmers have been wont to extend their acres by draining
wetlands, with disastrous effect on wildlife. Fortunately there has
actually been a reversal in this trend in recent years, with quite a few
people actually establishing or reviving wetalnds on their farms. In
many cases they have actively landscaped the land as well and created
some delightful watery gardens, so that everybody benefits.

A very serious loss of wetland has occurred here also on some coasts,
especially in our north which has extensive natural mangrove swamps.
Around Auckland in particular, where urban sprawl is at its worst, a
good deal of this land has in the past been drained to give more space
for housing. Fortunately, before it was all gone the important part
these areas play in fish breeding began to be appreciated and the  Dept
of Conservation made urgent moves to give them protection. For a country
where fising is a major industry the loss of breeding grounds must
obviously be excessively damaging.

An on-going battle also exists between those wanting to preserve intact
our already much-depleated remaining untouched native forests and others
who want to exploit them in various ways, from clear-felling to
sophisticated selective logging. A fair area in the south-west of South
Island has the protection of World Heritage status, but cynics may
wonder if this was only achieved because of the near-impossibility of
logging land where it rains about 350 days a year and the ground is like
one huge wet sponge.

We do in fact have enormous acreages of plantation pine (Pinus radiata)
which provides the bread and butter of the timber industry.
Unfortunately for those advocationg conservation native beech
(Notofagus) is well suited to chipping and some of our Podocarp timbers
such as Rimu and Kauri are highly sought after for fine joinery and
furniture. So much Kauri was however extracted about 100 years ago that
that now the remnants are nearly all protected and apart from recycling
old buildings, where it was once the principal timber and even 
harvesting ancient stumps, the only legitimate source of new wood is the
helicopter extraction of the odd giant which dies naturally. They
usually fly in a portable sawbench and then lift out the cut timber! No
scraps are wasted, as they are eagerly snapped up by wood carvers.

Rimu is still being cut, usually by selective logging as it does not
normally occur in pure stands. Much less is being extracted than
formerly and there is a good deal of reworked furniture on sale, but
conservationists would like to see further protection, as it too is
rapidly getting rarer. The bush area around were we live was logged for
Rimu around the turn of last century and we are delighted to see there
is now a good deal of natural regrowth, with young trees reaching a fair
size, but these are slow growers and need several hundred years to reach
maturity (Kauris even longer). Some deliberate replanting of the Kauri
has taken place in recent years, so their future looks a little
brighter. They actually grow quite fast in their early years and after
the first hundred may have a good part of their final height but a
pathetically small girth when compared with mature tree. Though not as
tall as your Redwoods these trees can achieve an immense bulk with a
scarcely tapering columnar stem which can yield enough timber to build
twelve small houses (or so it was once claimed). The largest known
surviving tree is named Tane Mahuta ("Lord of the Forest"). He has his
own visiting book, but in recent times he was found to be suffering root
damage from the feet of admiresrs and now one has to approach him on a
raised walkway. He is impressively tall as well as stout and the best
way to view his crown I found is to lie on the ground and look up!

One interesting development over the last few years has been an attempt
by this country to halt the excessive exploitation of timber on many of
the Pacific Islands. To replace the revenues these countries might
receive from such logging (IF they can wrest some of the profits from
exploiting multinationals) we have been encouraging the locals to
themselves make more use of the forests  for food, medicine and limited
timber extraction while also running ecotourism ventures to gain some
direct income. This seems to be working well in some places like
Vanuatu, where a good flow of tourists has been established and the
locals seem to be pleased with the way things are developing. Whether
the momentum can be maintained though, remains to be seen.

Moira
-- 
Tony & Moira Ryan <theryans@xtra.co.nz>
Wainuiomata (near Wellington, capital city of New Zealand)



-- 
Tony & Moira Ryan <theryans@xtra.co.nz>
Wainuiomata (near Wellington, capital city of New Zealand)
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