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Elozetes a Gaiabol.
(Mintha ez eltunt volna? Vagy csak nem
vettem észre)
Kornyesz #688, 1999. julius 10. Donella Meadows: The
forest is more than a collection of trees (Az erdo tobb, mint a
fak gyujtemenye)
Mintegy 40 evvel ezelott Herb Moore, a Dartmouth fiatal
tanara vett egy paradicsom-dugvanyt, ovatosan szetvalasztotta a
gyokereit ket kotegre es elultette azokat ket cserepben. Locsolta
mindkettot, amig azok nem indultak fejlodesnek. Azutan mar csak
az egyiket locsolta. A paradicsomok kifejlodtek, finomak volt.
Tobbszor megismetelte a kiserletet azzal a kiegeszitessel, hogy
egy masodik noveny vegig a viz nelkuli edenyben volt. Ezen is
termettek finomak, de masok elhervadtak, azonban sokkal
lassabban, mint *donor" nelkuli kontroll noveny egy szaraz
cserepben..
Kesobbi kiserletek azt mutattak, hogy egy noveny nem csak
vizet tud adni a masiknak, hanem radioizotopot is.
Borman asni kezdett a dartmouthi egyetem kozeleben egy
feher-fenyo erdoben s a gyokerekbe fecskendezett festekeket,
gyomirtokat es radioaktiv nyomjelzoket..Azt talalta, hogy a fak
nem csupan a kornyekukre adtak le ezekbol, hanem a gyokereik
osszetett *atultetett" halozatot, fonatot kepeztek (graft).
A nagy fak a tapanyagokat atadtak a kisebb, gyengebb faknak.
Borman szerint ezek a kiserletek azt mutattak, hogy a
vetelkedesnek a tulelesben valo szerepet tulertekeltek. Sok fa
osszekapcsolodott egy szerves egysegge, a resztvevok
elveszitettek az egyeniseguknek legalabb is egy reszet es a
halozati tarsaik is hatottak rajuk.
Ekkor mar ismert volt, hogy tolgyfak betegsegei a gyokerek
szovedeken at egyik farol a masikra terjednek. 1966-ban Borman
es munkatarsa egy osszefoglalo munkaban 180 tudomanyos
kozlemenyt sorolt fel, amelyek arrol irtak, hogy anyagok jutnak at
egyik fabol a masikba. 150 farol voltak adatok - tolgyfa, juhar,
hars, fenyo, lucfenyo, koris, vorosfenyo, erdei fenyo, nyir.
Olykor ket kulonbozo faj ad egy halozatot, - pl. juhar+nyir,
nyir+szilfa, szantal+ a tropusi Eugenia-fa.
Az anyagszallitas gyakran a gyokerek fonatan at tortenik.
Maskor a talajon at, mint a Bormann-paradicsomnal. Olykor
vannak a fak kozotti kozvetitok, egyuttmukodo gombafonatok,
mycorrhizak, amelyek osszekeverednek a gyokerekkel, a
falevelek altal termelt cukrokbol elnek, es tapanyagokat vesznek
fel a talajbol. A cukrokon kivul vandorolnak a novekedesi
hormonok, gyomirtok, korokozok is, kevesbe gyakran a viz es
asvanyi anyagok.
Ezt az anyagforgalmat jol ismerik a biologusok, de nem sokat
foglalkoznak vele. Meglepodtem, amikor nehany honappal ezelott
egy erdo-okologus, Scot Tens egy beszelgetesekben emlitette a
gyokerfonatokat - en semmit nem hallottam errol korabban.
A gondolat megvaltoztatta a nezetemet arrol, hogy mi is az
erdo.
Micsoda? A gyokerek egyutt novekednek? A fak anyagokat
adnak le? Mit jelent ez?
Mit jelent ez az erdogazdalkodas, a valogato betakaritas, a
tarvagas eseteben? Mit jelent, ha savas eso esik, ha szarazsag
jon, ha gyomirtokat fecskendeznek, ha ki akarjuk pusztitani a fak
korokozoit? Hogyan befolyasolja ez azon nezetunket, hogy a vilag
a vetelkedes es nem az egyuttmukodes reven halad elore?
Elterit-e azon nezetunktol, hogy inkabb egyedek gyujtemenyet
latjuk es nem osszekapcsolt rendszereket? Eddig nem lattuk a
faktol az erdot? Ha kivagunk egy fat, de bennhagyjuk a ronkot,
nem segit a betegsegek megelozeseben. Ha egyes kivalasztott
faknak adunk gyomirtokat, az szetterjed es megmergez celba nem
vett fakat is. Az osszekottetesben allo fak valoszinuleg sokkal
ellenallobbak a szellokesekkel szemben, de kevesbe a betegsegek
irant.
A szalalo vagas varatlan eredmennyel jarhat - lehet, hogy nem
egy vetelkedot vagunk ki, hanem egy (elet)tarsat.
Szeretnek melyebb tanulsagokat levonni, mint ezeket a
gyakorlati dolgokat. A professzoraim a vetelkedes fontossagat
hangsulyoztak, azonban en inkabb az egyuttmukodest fogadom el
mukodesi elvkent. Szeretek osszetett, kolcsonhatasban levo
rendszerekben gondolkodni. Van egy osztonos, egyesek szerint
esszerutlen nezetem, hogy az erdo tudja es megsiratja, ha egyetlen
fa kidol.
Szeretem a fak kozotti titkos forgalomra vonatkozo nezeteket.
Nem vagyok vak a termeszetbol levonhato leckek irant. Aha! -
A nagy fak tamogatjak a kicsiket. Ok egyutt allnak, nem kuzdenek
egymas ellen. Ha egyet kivagunk, mi hullamokat kuldunk a
kolcsonos osszefuggesben levo kozossegen at.
Ha ez igaz a fakra, akkor miert ne lenne igaz az emberekre?
Ez termeszetesen tul van egyszerusitve, van sokfele vetelkedes
is az erdoben. A halozat tovabbjuttatja a betegsegeket, a
mergeket, ahogyan a tapanyagokat es hormonokat is. Senki sem
tudja az okat, ha van oka, hogy egy fa miert osztja meg mindenet
a tobbivel. A termeszet tulsagosan osszetett ahhoz, hogy
megerositsen barmifele egyszeru vilagnezetet.
Pi
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Volume 291, Number 5501, Issue of 5 Jan 2001, pp. 48-49.
ESSAYS ON SCIENCE AND SOCIETY:
Toward Sustainable Chemistry
Terry Collins*
2. resz
---
In their current formal training, all chemistry students will learn that
the chlorination of phenol proceeds by a mechanism known as electrophilic
aromatic substitution. But very few will learn of EDCs and their dangers or
come to know that prime examples of EDCs, namely PCDDs, are produced in
trace quantities whenever phenol is chlorinated. This hazardous omission
illustrates one important type of content that is simply missing from the
conventional curriculum.
Green chemistry can dramatically reduce environmental burdens of both
classes of persistent pollutants by moving the elemental balance of
technology closer to that of biochemistry. Significant reductions in the
dispersal of many persistent pollutants have already been achieved. By the
late 17th century, the use of lead oxide as a correcting agent for acidic
wine was banned on pain of death in Ulm in the duchy of Wurtemburg.|| More
recently, large reductions in lead pollution have been achieved in what are
recognizable examples of green chemistry, for instance, by replacement of
lead additives in paint with safe alternatives, by the development of
cleaner batteries, and by the as yet unfinished and sometimes flawed
progression away from tetraethyl lead toward safer combustion promoters in
fuels. PCDDs and PCDFs have been greatly reduced in the pulp and paper
industry by the replacement of chlorine with chlorine dioxide as the
principal bleaching agent.
Nevertheless, much more can and must be done. For example, chlorine-based
oxidations such as pulp bleaching, water disinfection, household and
institutional cleaning, and clothing care continue to produce huge volumes
of organochlorine-containing effluent. Despite industry efforts to reduce
pollutant concentrations, some of the inescapable trace contaminants are
persistent, bioaccumulative carcinogens and/or EDCs. Chlorine-based
oxidation technologies could be replaced with alternatives based on
catalytic activation of nature's principal oxidizing agents, oxygen or
hydrogen peroxide. My research group has patented TAML activators, which
are potent but selective peroxide-activating catalysts comprised of
biochemically common elements for these and other fields of use.
Environmental considerations also underpin the worldwide investigation and
development of supercritical and near-critical carbon dioxide as a clean
solvent. The present search for safer solvents in the green chemistry
community is distinguished b
y a remarkable burst of creativity that perhaps reaches its zenith in ionic
liquids. These solvents have unique properties such as the absence of any
vapor pressure under standard conditions.
Pollutant production can also be reduced by improving process selectivity,
reducing energy intensity, and minimizing the flow of matter to and from
the ecosphere via atom economic processes, that is, processes optimized to
reduce per unit of product the quantities of chemicals employed in the
reactions as solvents and reagents or produced as by-products.
To achieve such sustainable chemistry requires a sea change in the chemical
community. The principles of green or sustainable chemistry must become an
integral part of chemical education and practice. However, there are
several obstacles to overcome. First, chemists need to comprehensively
incorporate environmental considerations into their decisions concerning
the reactions and technologies to be developed in the laboratory. These
questions need to become as important as those associated with the
selectivity of the technology and how it works. Principles upon which to
base these decisions have already been developed. Second, it is critical
that chemistry that is not really green does not get sold as such, and that
the public is not misled with false or insufficient safety information. For
example, certain chlorine industry companies have sought to protect their
profits by distorting scientific data to make dioxins appear to be less
harmful to humans than they actually are. The general trust that chemical
ris
k is treated in a fair and reasonable manner must be strengthened. Third,
since many chemical sustainability goals such as those associated with
solar energy conversion call for ambitious, highly creative research
approaches, short-term and myopic thinking must be avoided. Government,
universities, and industry must learn to value and support research
programs that do not rapidly produce publications, but instead present
reasonable promise of promoting sustainability. Fourth, chemistry exerts a
near boundless influence on human action and is thus inextricably
intertwined with ethics. An understanding of sustainability ethics* is
therefore an essential component of a healthy chemical education.
The all-encompassing challenge lying before green chemists is to understand
the ethical forces, chemical-ecosphere relations, educational needs, and
research imperatives that sustainability brings center stage and to
reconcile this understanding as much as possible with economic maxims. If
chemists increasingly direct their strengths to contributing to a
sustainable civilization, chemistry will become more interesting and
compelling to people, and may lose its "toxic" image. It will become more
worthy of public support and spawn exciting economic enterprises that
nurture sustainability.
---
The author is at the Department of Chemistry, Carnegie Mellon University,
Pittsburgh, PA 15213, USA. E-mail: .
*H. Jonas, The Imperative of Responsibility: In Search of an Ethics for the
Technological Age (Univ. of Chicago Press, Chicago, 1984).
P. T. Anastas, J. C. Warner, Green Chemistry: Theory and Practice (Oxford
Univ. Press, Oxford, 1998).
J. Thornton, Pandora's Poison: Chlorine, Health, and a New Environmental
Strategy (MIT Press, Cambridge, MA, 2000).
$A4R.K. Katz, Ed., Endocrine Disruptors: Effects on Male and Female
Reproductive Systems (CRC Press, Boca Raton, FL, 1999).
||J. Eisinger, Natural History, 105, 48 (1996).
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Udv minden Kornyeszesnek!
A segisegetekre lenne szuksegem(unk)!
Kishegyesrol irok, ami Vajdasag kozepen(sziveben) helyezkedik el.
Ez egy 5-6ezer lakosu falucska, egy 13e embert szamlalo
kozsegben, feluton a Szabadkat Ujvidekkel osszekoto autout mellett !
Es van egy maroknyi lelkes fiatal, akik mindent megtennenek
azert, hogy ezt a kornyeket szebbe varazsoljak, es a termeszetnek
megadjunk minden segitseget, hogy kiheverje az utobbi nehany
(minden tekintetben nehez) evben ert seruleseket.
A lelkesedes mellett azonban szuksegunk lenne a Ti velemenyetekre,
tanacsaitokra, otleteitekre! Esetleg cimeket, weboldalakat ahol
ilyen temakban lehet tudakozodni.
Mindenki segitseget elore is koszonom!
Csore Robert
Platan Kornyezetvedelmi Mozgalom - Kishegyes
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