Transcript Survey5Forest Mensuration

Oku losZ{k.k
Ekkiu & 2
Ok`{kksa dh ÅapkbZ Ekkiu
Forest Mensuration
• bl l= dk mn~s’; izf’k{k.kkfFkZ;ksa dks ou ekiu ds ckjs fuEu
dh tkudkjh nsuk gS %
– ifjHkk"kk,a
– mapkbZ ukius ds fl)kar
– mapkbZ ukius ds midj.k
Aims: The aim of this session is to help trainees in
analysing the following aspects of Forest
Mensuration:
1.
Definitions
2.
3.
Height measurement principles
Instruments of height measurement
ifjHkk"kk,a Definitions
• dqy ÅapkbZ ¼VksVy gkbZV½ ;g t+ehu Lrj ls N= ds lcls maps fcUnq
dh lh/kh nwjh gS A
• BwaB ÅapkbZ ¼ cksy gkbZV½ ;g t+ehu Lrj ls igys N= fuekZ.k djus
okyh igyh thfor ;k e`r 'kk[kk dh nwjh gS A
• Total height: is the straight-line distance from the highest point of the
crown to the ground level.
• Bole height: is the distance from the ground level to the position of the
first crown forming living or dead branch.
ifjHkk"kk,a Definitions - 2
• BwaB ÅapkbZ & BwaB dh t+ehu Lrj ls f’k[kj rd dh mapkbZ gS A
• N= yEckbZ& ;g og lh/kk uki gS tks N= ds f’k[kj ls ysdj ] BwaB dh lcls fupyh gjh
'kk[kk o fupyh gjh 'kk[kkvksa ftu ls gjk N= curk gS] ds e/; fcanq rd gS A
• N= ÅapkbZ & ;g tehu Lrj ls ysdj rus dh lcls fupyh gjh 'kk[kk o fupyh gjh
'kk[kkvksa ftu ls gjk N= curk gS] ds e/; fcanq rd dh mapkbZ gS A
• Stump height: is the height of the top of the stump above ground.
• Crown length: is the vertical measurement of the crown of a tree from
the tip to the point half way between the lowest green branches
forming green crown all round and the lowest green branch on the
bole.
• Crown height: is height from the ground level to the point half way
between the lowest green branches forming green crown all round
and the lowest green branch on the bole.
mapkbZ ukius ds fl)kar
Height measurement principles
• VªhxukseSfVªd fl)kar & VªhxukseSfVª xf.kr dh og 'kk[kk gS tks dks.kksa o f=Hkqtksa dh
Hkqtkvksa ds uki o mu ij vk/kkfjr dk;ksZa ls lac/k j[krh gS A
• ftu rhu VªhxukseSfVªd dk;ksaZ ¼ lkbZu] dkslkbZu o VSUtsaV ½ ds lac/k esa ge ckr dj jgs gSa
os f=Hkqt dh nks Hkqtkvksa dh yEckbZ dk vuqikr gS A ;s vuqikr ,d dks.k ¼FkhVk½ ds ,sls
VªhxukseSfVªd dk;Z gSa ftlesa foijhr Hkqtk o`{k dh ÅapkbZ dks bafxr djrh gSA
•
Trigonometric principle: Trigonometry is a branch of mathematics dealing
with measurements of the angles and sides of triangles, and functions
based on these measurements. The three basic trigonometric functions
that we are concerned with here (sine, cosine, and tangent) are ratios of
the lengths of two sides of a triangle. These ratios are the trigonometric
functions of an angle, theta, such that here, opposite side (y) refers to tree
height.
leku f=Hkqt ds fl)kar
PRINCIPLE of SIMILAR TRIANGLES
leku f=Hkqt os f=Hkqt gSa ftuds rr~LFkkuh dks.k rks leku gSa ijUrq ftudh
rr~LFkkuh Hkqtk,a vyx yEckbZ dh gks ldrh gSa A
Similar triangles are triangles whose
corresponding angles are the same, but whose
corresponding sides may be of different lengths.
C
A
D
F
E
B
Thus △ABC is similar to △DEF: f=Hkqt ABC f=Hkqt DEF ds leku gS
∠ABC=∠DFF; ∠BCA=∠EDF; ∠CAB=∠DEF
leku f=Hkqt SIMILAR TRIANGLES - 2
D
A
B
AB / DE = AC / DF
C
E
F
leku f=Hkqt SIMILAR TRIANGLES - 3
vH;kl 1 Exercise 1
;fn vki tkurs gSa fd nks f=Hkqt leku gSa rks vki lekurk dh ifjHkk"kk ds vk/kkj ij ;g
Hkh izekf.kr dj ldrs gSa fd
1 f=Hkqtksa dh rr~LFkkuh Hkqtk,a vuqikfrd gSa vkSj
2 f=Hkqtksa ds rr~LFkkuh dks.k vuqdwy gSa A
If you know two triangles are similar, you can use the definition
of similarity to prove:
1. Corresponding sides of the triangles are proportional, and
2. Corresponding angles of the triangles are congruent
If the tree’s shadow is 50’ long & the
woman’s shadow is 10’ long; how tall is
the tree if the woman is 6’ tall?
vxj isM+ dh Nk;k 50 QhV yEch gS vkSj efgyk dh 10
QhV rks isM+ fdruk mapk gS ;fn efgyk 6 QhV yach
gS
leku f=Hkqtksa ds fl)kar ij vk/kkfjr midj.k
Instruments based on properties of similar
triangles
• fØlfpu fgIlksehVj Christen's hypsometer
• fLeFkht+ fgIlksehVj Smythies' hypsometer
• mUur dSfyilZ Improved callipers
fØlfpu fgIlksehVj
Christen’s Hypsometer
VªhxukseSfVªd fl)karksa ij vk/kkfjr midj.k
Instruments based on trigonometric
principles
•
•
•
•
•
czSafMl fgIlksehVj Brandis hypsometer
,cuht+ ysoy Abney's level
gkxk vkYVhehVj Haga altimeter
Cywe&yhl fgIlksehVj Blume-leiss hypsometer
jSykLdksi Relaskop
Trignometric Principle
VªhxukseSfVªd fl)kar
,cuht+ ySoy Abney Level
,cuht+ ySoy & dSls bLreky djsa
ns[kus okyk isM+ ls nwj ml LFkku ij [kM+k gksrk gS tgka ls isM+ dh
pksVh o ry nksuksa fn[kkbZ nsa A fQj vkbZihl fudkydj mlds fiugksy
ls isM+ dh pksVh dks ns[kk tkrk gS A blls midj.k Vs<+k gks tkrk gS
'kh’ks esa cqycqyk ugha fn[kkbZ nsrk gSA blfy, isM+ dh pksVh
ns[krs le; isp dks ?kqek;k tkrk gS rkfd fLifjV ysoy {kSfrt voLFkk esa
vk tk, A fLifjV ysoy dks yxkrkj /khjs /khjs fgykdj ml fLFkfr esa yk;k
tkrk gS tc cqycqys dh Nfo dks {kSfrt rkj dh ykbZu 'kh’ks ij nks cjkcj
Hkkxksa esa ckaVs vkSj nwljs fgLls esa isM+ dh pksVh {kSfrt rkj dks
Nwrh fn[krh gks A bl fLFkfr esa isM+ dh pksVh ds mBku dk dks.k
i<+ fy;k tkrk gS A blh rjg ry ds <yku dk dks.k i<+ fy;k tkrk gS A fQj
mi;qDr QkZewys ds ek/;e ls isM+ dh mapkbZ fudkyh tkrh gS A
Abney Level – How to use?
The observer stands away from the tree at a place from where
the top of the tree and the base are visible. Then the top of the
tree is sighted through the pine hole of the eyepiece after pulling
it out. This makes the instrument inclined and the bubble is not
seen in the mirror. Therefore, while sighting the top, the screw is
Rotated to bring the spirit level in a horizontal position. The
spirit level is continued to be moved slowly to the position
when the bubble image is bisected by the line of horizontal wire
on the mirror and in the other half the tree top is seen touching
the horizontal wire. At this position, angle of elevation to the top
of the tree is read. Similarly, the angle of depression to the base
can also be read and the height of the tree determined by using
suitable formulae
,cuht+ ysoy
,cuht+ ySoy ds ykHk :
1 ouhZ;j ds lkFk mBku o <yku ds lVhd dks.k nsrk gS A
2 NksVk o gYdk gS vkSj igkM+ksa esa vklkuh ls bLrseky fd;k tk
ldrk gS A
,cuht+ ySoy dh gkfu %
1 gkFkksa dh daiu ls isM+ dh pksVh ;k ry dks ns[kuk FkksM+k eqf’dy
o le; yxus okyk gS A
2 LihfjV ySoy dks isp fgykus ds lkFk isM+ dh pksVh ;k ry dks ns[kuk o
,SMtLV djuk ] Fkdkus okyk dk;Z gS A
Abney Level
Advantages:
1. Gives accurate angles of elevation or depression with the
vernier
2. Small and light and can be used even in hills without
difficulty.
• Disadvantages:
1. Shaking of the hand makes the sighting of the top or
bottom of the tree a little difficult and time-consuming
2. The spirit level has to be adjusted by moving the head of
the screw while simultaneously looking to the top or
bottom of the tree. This is quite tiresome.
Cywe&yhl fgIlksehVj
Blume Leiss Hypsometer
gkxk vkYVhehVj Haga Altimeter
vH;kl&2
• Økmu gkbZV dk D;k eryc gS\
• mapkbZ ukius ds fl)karksa dk fooj.k nks A
• isM+ dh mapkbZ ukius ds fy, VSatSaV eSFkM dk fooj.k
nks A
• mapkbZ ukius ds midj.kksa dh lwph nsa A
• ,scht+ ySoy ds ckjs esa o ykHk & gkfu ds ckjs esa fy[ksa A
• leku f=Hkqtksa ls vki D;k le>rs gSa \
Exercise - 2
• What do you mean by crown height?
• Describe the height measurement principles.
• Describe the height measurement of a tree by
using tangent method.
• List the instruments of height measurement?
• Describe the Abney's Level, its advantages and
disadvantages.
• What do you understand by Similar Triangles?
THANK YOU
/kU;okn