Day 268 - 24 Jun 96 - Page 26


     
     1        soil aluminium, which is present at toxic levels for
     2        virtually all cultivated crops.  The cost of this
     3        application is about US $350 per hectare and represents
     4        nearly twice3 the purchase price of the virgin land.  The
     5        arable crops planted are, in order of importance, soya,
     6        maize, rice and mandioca.  Soya is at present enjoying a
     7        good price on the export market and occupied no less than
     8        3.9 million hectares of cerrado in 1994, producing 8.8
     9        million tonnes, while 4.0 million tonnes of maize were
    10        produced (World Wildlife Fund Brazil, pers. Comm).
    11        However, far more of the cerrado is exploited as improved
    12        pasture, planted with such exotic grasses as Brachiaria,
    13        Hyparrhenia rufa and Panicum maximum, than as arable land.
    14        It is difficult to find recent figures for the number of
    15        cattle raised on the cerrado but in 1995 it was estimated
    16        at 38 million and the present number is certainly much
    17        higher.
    18
    19        The system of cultivation of the cerrado is far from
    20        environmentally friendly.  The employment of intensive
    21        mechanization requires huge tracts of monoculture with
    22        great areas of bare soil and the concomitant problems of
    23        erosion by rain and wind, while the legally required
    24        reserve areas have to be kept in concentrated blocks so
    25        that the trees do not impede spraying aircraft."
    26
    27        Can I just say that the reserve areas he is referring to
    28        will be in a biological sense rather than Indian reserves.
    29
    30        "Clearly it would be better if such reserves were dispersed
    31        as a web to act as corridors for animals and a more
    32        widespread seed source for recolonization.   Incidentally,
    33        the Brazilian laws for maintenance of reserve areas are
    34        extremely enlightened, requiring 50% of land to be kept
    35        under natural vegetation in Legal Amazonia and 20% in all
    36        the rest of Brazil.  If such laws were strictly observed,
    37        problems of conservation would be greatly reduced.  Of the
    38        many other environmental problems, heavy, and often
    39        careless, use of pesticides and depletion of water reserves
    40        by giant rotating irrigators are amongst the most
    41        important.
    42
    43        Obviously the cerrado biome has received a formidable
    44        agricultural onslaught and has been much altered during the
    45        last 20 or so years.  It is very difficult to estimate the
    46        total area which has been changed to arable, planted
    47        pasture or other man-made landscape but a conservative
    48        figure seems to be about 40% (Ratter, 1991; Dias, 1992; WWF
    49        Brazil, pers. Comm).  It is interesting to compare this
    50        with the well-publicized figures for destruction of the
    51        Brazilian Amazonian rainforest, for which accurate
    52        information is available.  To date approximately 450,000
    53        square kilometres of rainforest, representing some 13% of
    54        its original area has been destroyed, while at least
    55        800,000 square kilometres of cerrado, 40% of the original
    56        area, has suffered a similar fate.  So much emphasis has
    57        been put on the emotive issue of the destruction of the
    58        rainforests that the world has largely forgotten the fate
    59        of their floristic cousins, the savanna woodlands.
    60

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