----- Original Message -----

From: Pankaj Oudhia

To: jatropha@...

Sent: Tuesday, March 25, 2008 9:37 AM

Subject: [jatropha] Re: On biodiesel and perpetual motion ?

Thanks Viren for your message. Here is minor correction in your
message. You have written.

'jatorpha has deveolped allelotrophic properties'

In fact Jatropha *possess* Allelopathic properties. It secrets so many
allelochemicals in soil. These allelochemicals inhibit growth of
native flora. Hence large scale plantation of such plants having
strong allelochemicals is curse for biodiversity.

When I was in Agriculture university I conducted small trial to study
allelopathic effect of Jatropha on Pigeonpea. Here is reference. This
lab study showed that Jatropha extracts are harmful to this crop
widely cultivated in crop bund where Jatropha plantation is in
progress in many parts of India including in Chhattisgarh.

http://ecoport.org/ep?SearchType=reference&ReferenceID=556604

Through on-going surveys I have listed over 500 native species
affected by Jatropha allelopathy.

What is status of pest infestation in Jatropha in your state?

regards

Pankaj Oudhia

--- In jatropha@yahoogroups.co.in, "Viren Lobo" <vlobo62@...> wrote:
>
>
> The Government policy on Biodiesel is based heavily on jatropha,
which they say can grow anywhere . particularly on wastelands and with
very little water .. .. To grow sucessfully in such conditions,
jatorpha has deveolped allelotrophic properties. ...... So what will
happen when millions of hectares are put under this plant ? The cut
paste from Robert Mc Arthurs book on Geographicla ecology shows that
under Gaus principle... no two species can live in the same niche ...
There has to be two distinct niches for them to exist .... The multi
species of the wet tropics, makes use of abundance to create such
multiple niches . In desert and semi desert conditions, a number of
unqiue niches are also created to use sun, rain and the nutireints
present in the soil.... What is the understanding of the those who in
thier wisdom think that jatropha is an answer to Inida's fuel crisis ???
>
>
> Viren
>
>
>
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>
> Some snippets from Robert Mc Arthurs book on Geographical ecology
>
>
> To do science is to search for repeated patterns not simply to
accumulate facts and to do the science of geographical ecology is to
search for patters of plant and animal life that can be put on amp .
>
> The theme running though this book is that he structure of the
environment , the morphology of the species , the economics of species
behaviour and the dynamics of population changes are the four
essential ingredients of all interesting biogeographic patterns ..
>
> Impact of adaibatics
>
> The derivation of adiabatic lapse rate is simple using the first
law of thermodynamics , the ideal gas law , and the rate of pressure
change with elevation . But since each of these has its own empirical
constraints , it is no greaer burden simply to assume the lapse rate
as an empirical rule . The derivation does show however that the
cooling rate is approximately constant....... We can now see why
mountaintops are cooler than lower elevations. In fact 3^F cooling of
100 feet of elevation on a moist mountain is very roughly equal to the
cooling of 100 miles of latitude , which has been called " hopkins
bioclimatic law " .
>
> now we suppose there is a small parcel of air being lifted by the
turbulence and cooling adiabatically f course as it rises . This air
finds itself less cool than the neighbouring air at each elevation and
hence it is lighter and continues to rise sucking up the air behind
it. .. this is called unstable. air which cools slower than than
adiabatic is stable and not vulnerable to eddies and disturbances ....
Warm air over a cold nocturnal desert is stable but gives way to
unstable air and dust deveils as the desert warms up in the day time .
>
>
> On competition
>
> For years ecologists were plaugued by an apparent paradox. many
species seemed to coexist in nature but not in the laboratory
experiments .. ...There has arisen from these and similar experiments
a widely accepted belief called the principle of competitive exclusion
or gause's principle .. The principle states that two species cannot
coexist unless they are doing differnt things or more baldly unless
there are two nches
>
> some terms
>
> competitor similarity - the more similar the competing species,
the smaller their zone of geographic or habitat overlap
>
> diffuse competition - sevarla competitors which can outcompete a
single species.
>
> resource overlap - the coexistence of two or more competitors
becomes rapidly more preacrious as the distance between their resource
mean approaches root 2 times thier standard deviation
>
> geographic sequences - along a geographic continuum two
competitors may be found in either of the following sequences 1. one
species then both , then the other 2. one species , then a vacant
zone , then the other .
>
> Volterra's thoery on competition
>
> equation to explain coexistence or one species replacing another.
>
>
> The economics of consumer choice
>
> Thus from a foraging birds point of view , there is a great
diversity of foliage types , from tree trunks to loose canopy , to
bushes to herbaceous ground cover , but each is repeated so that a
tree trunk feeder for example can find many trunks to search . This
postulate at least is required because it means that a searching bird
will have a fairly clear staititical .
>
>
> Functional morphology
>
> Some sort of continuity principle seems to be minimal: that nearby
morphologies are adapted for nearby methods of harvesting food.
>
>
> Cody 1971 has studied the economics of flocking behaviour of
fringillid species in the Mohave desert . He argues that foraging
flocks accomplish two things that are are not readily accomplished by
an individual acting independantly . First exploited vs unexploited
areas are more easily recognised with the result that S is reduced .
Second int he case of renewable resources flock behaviour can evolve
in such a wya as to optimze the return time to previous expoited areas.
>
> Compression hypothesis
>
> As the number of competing species incress feeding habitats
contract and the actual range of food items taken either remains
constant or actually increases slightly . .... Ocassionally however
the competitors may reduce the food in a species own favoured
location. In such situations the effect would be to increase the
species range of foraging species.
>
>
> The ringed kingfisher . should perch so that the greatest number
of grams of fish per day can be captured . so it perches high enough
to search a wide area for big fish .. but notice how this restricts
its diet : by perching so high so that it can survey a large area, it
can no longer see the very small fish .. and even if it did the
energy expended would not compensate for the long dive...
>
>
> Viren
>