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roral mp yields, rneher inan dedueis [mm ihenr in
gene-ah we would gain in pop 57 pashiie yield using
riiuogen fixing and bmedibk shehereeiis species,
and lone uvp yield by using high werer—dernend, non.
ieguuunoiis, and inedilile shdreroell ipxizi
However, where we experierroe revere wa ur deeri
winds, which grearly reduee all yields, we iniiar aelea
sakrresihnm er sandrblastrleslslam wlndbruk nu
inaxner whai ihe inieirisie yields oi ehe sheireroelr. ii is
rare lor iea-Ironl nee- lo hear eneerively leg. ihe nuier
«5 rows nl eoeonurs on Exposed islands yield lirlle
map), so rhae oneroe m honuine seaeeasi planis hrr seed
or lriul yields is oilen irrelevnni when epnsidering
speeieslorrnuldple film,
For noisied uees, or ones whose ampy Ims above
she general loreri level wind nl even low speeds nray
inerease ihe lranrplraiiori rnle, aorneliniea doubling
warer use. The {find ugreaiesr on walenlovrng plania,
and iriueh less or. dry/adapted speeies which have
impermeable lerl mode and good eonuol M woman,
or a edver olsplnes and hares
Ha, dry wrndi, and winds laden wiih sail have ihe
rnoar damaging eheer on pirnr yields (lie-we, aniinal
yields), alrhough at high wind ipeedi ineehnnienl
danrage ran oeeur, whreh preyenis or reduces yields no
iriarier wnai ihe hurnidiiy or sah eonreni oi ihe winds.
Damaged map plums such as eorn or ban-nus suiier
phorosyneihie inelhrirney ranging horn 20-357. when
ihe leal lrnirnae are iurn or lrayed, or ihe ribs are
bluken (Chang, weal
rlarirs show dillerenr resisrnnees lo wind dnrriage
- wind lolrrenl (and wind-lasi) These are ihe rriany
shori or ereeping planrs ar ihe boundary layer ol shll air
near ihe ground, or lire hunkhne planrs el sea (oasis.
eg. Cerosliurn, Amuwn'a heierophylls Yields are lliile
alieeied by snong winds
~ Exyuslur Ioltmnl, e.g, barley, some Brasslas,
Casuaririii and Cvpmsma repens Yield: are redueed in
slrong winds, our dry riialrer yield is less alleered lhan
in windeereriive planis
. wind sensiine. These are ihe niany unporrani erups
* §
§ ii
lg §
2 it
¥
5 §
. ei. new
at;
FIEHIE 5.11
WAVER USE AND wuw PRODUCED
"I: mm ol hrouuow insruse yields on burl ilurs our mulls!
my use
such as eiirus, avoerdo, iriwrlruir.vines, inany
deeiduous hulls. eorn, rue-r cane, and blnims aoeh
plane helyu and yields rapidly decrease wlrh inneases
in wind speed Fur ihese species, very irrrensive
ihelierlreii sysienia are mnfli].
l-roplenir arise when ihe planrs used lor snelierlreli
leg puplar) are iheinseives heavy wale'reuu speeiea
wirh invasive roora. An annual rode—eurring or rrp—hne
niay ire necesary along rueh windoiealis re penrul ihe
nop sheliered is ooiain sunieieni waier, but ii is pier in
ehoose uioresuiraole spedes in llie hisipiaee,
H - i
ihe herein and densiiy, or peneuaoihiy, ol windineaii
irees are ihe erieieal shelrer—elieol laeiors sirrne
rotlfigumlimis ol windireli rnay causes hoskpoekets in
develop in ene sirll air oi shelrered hollows,
PERMEABILITY ii an iinporranr lneior ii we wanr lo
reduce (mil nsk or lo exeend ihe wlndbreak elleer
lrigure 5.16)
Briefly, we need windorealrs spread ai no mm mm m
runes rhe hedgerow heighr in any severe wind. in ihe
esralrlishrnenr oi wind—sensilive lree crop we may
reruaiiy need eeniinuous linieiplanil windhreak Th1
lengih el windhmk needs in he gamer ihan ihe lengih
or ihe held proieded, as wind runnels nrnund die end
ulwindlamuin a regular now paiiern,
Windmik Cengguraiions
in general, speeies ehnsen lor windereak should per-nil
40-70% ol ihe wind ihrorigli. whreh prevenrs ihe
lonnairon at a hirhuleni wind ovenuin nii ihe leeward
side. Windhuk neighr is ideally onehhh el ihe spare
heiween windbreaksbul is siill eneerrve lor low crop ri
oneihrriieih ol lhe inlerspree
sensiiile mnllgnrirlans are shown in figure 5. 1
NM: ihai seine wind siielier sysienis are placed
lhmughoul or wiihui lire rrnp or (mil area
A Dense wllmbrmk will. hare riern area bdaw. Elleers,
good summer eool shade lor liveslocle poor lo useless
winier sneiier. clunrps oi sueh irees on knolls allow
aniinalr lo escape heal, and dies and rnosuunoes are
rnueh iedueed.
W Cums“, piriris, Casuamia
n Alierriaie lug—ergl pianiing or very permeable
irees, gums: good lruru-line“ serironi sysierns m
redure sail burn and provide shelrer (or more dense
ireee on islands and coasls giggles Amucnnn, pines,
Casuarlm
c, Compound vnndlrreal or high densiiy mm» The
bear pmledion lor eroding heeehes, lining ihe wind
sniodrhly over ihe her-4h berrn nnd napping sand, Also
eheeiive in dusksmlm areas as a dual luv» 5%.
Ground Connuluulus, Phyla lLippiul, Mrstmbrye
sniieniurn Low shrubs erhiuni uiiueiiim, worrnweod,
shrubs» Cupmsma rems Trees Lytlum. Cedrus,
ciinresslis, soine planrs
127