afforestation of denuded hill slopes mahesh kumain
TRANSCRIPT
Presented by
Mahesh Kumain
M.Sc. Student
IoF, Pokhara
Roll No: 11
Section
General forestry
Afforestation of Denuded Hill Slopes
Presentation outlines
Introduction
Methodology
Discussion
Conclusion
1. INTRODUCTION
Silvicultura
• Silvicultura is the practice of controlling the
establishment, growth, composition, health, and
quality of forests to meet diverse needs and values.
• Silviculture is that branch of forestry which deals
with the establishment, development, care, and
reproduction of stands of Timber.
Regeneration
Regeneration is defined as “the renewable of a forest
crop by natural or artificial means.”
Methods of regeneration
There are two main methods of regenerating forest
crops
1. Natural regeneration,
2. Artificial regeneration
The objectives of artificial regeneration are:
1. Reforestation
2. Afforestation
Regeneration…
Reforestation: Restocking of felled or otherwise cleared woodland by artificial means.
Afforestation : Establishment of a forest by artificial means on an area from which forest vegetation has always or long been absent.
Objectives of Afforestation
To increase the production of timber.
To increase the production of fuel and small timber.
Soil conservation.
Protection of catchment of rivers.
Increasing natural beauty of landscape
Denuded hill slopes
simply denuded means “Nango Danda pakha”.
About 85% area is covered with hills in our country.
They are also sloppy, some are covered with vegetations
and some are naked , eroded, degraded.
In most area some vegetal cover establishes naturally,
but in drier parts of the country, their afforestation
becomes a matter of importance not only for productive
and bio-aesthetic reasons but also for conservation of
soil and water.
2. METHODOLOGY
Basically, this term paper has been prepared
through literature survey from internet, books
and publications. No field visit has been made
for this purpose.
3. DISCUSSION
DISCUSSION …
The following things should be considered while
afforestation in denuded hill slopes:
1. Factors of locality and other conditions: Soil is poor,
shallow and stony. Excessive soil erosion, excessive
runoff, The incidence of grazing which was one of the
most important cause of denudation is very heavy.
2. Closure: Before starting afforestation work it is necessary
to close the area by fencing or by the cooperation of local
people against felling, grazing and firing for 2-3 years.
DISCUSSION …3. Soil preparation: Soil preparation is done either in the form
of
A) Contour trenches:
Contour trench are usually made on slope upto 20% as the
operation becomes costly on steeper slope.
They are usually made with the help of any leveling
instruments.
In forest, Abney’s level, which is the easiest instruments to
use, is generally used.
Alternatively, the contours can be easily marked by any
locally improvised wooden contouring frame,
DISCUSSION … structure A contouring frame in the form of letter “A” of English
alphabet is made of 5-6 cm wide sown timber piece, 1-2 cm
thick. Two such pieces are joint to make “A” of height 1.5m
with legs about 2m apart. To keep the legs in position, they are
strutted with a horizontal piece on which is middle point is
marked.
A plumb bob is suspended from a nail fixed in the apex. When
thread of the plumb bob pass through the middle point mark
of the horizontal piece, the two points on which the
contouring frame stands, are on the same contour.
1.5m
2m
Plumb
bob
fig. Contouring frame with a plumb-bob
DISCUSSION … structure
DISCUSSION …
B.Pitches or pits:
In place where the slope is rocky and contour
tranches can not be made, patches for sowing and
pits for planting may be made at selected places
marked by stakes without bothering for regular
spacing.
DISCUSSION …
4. Choice of species: The selection of species
depends on different factors but should be selected
indigenous species as possible. The fast growing ,
non-palatable species which can survive under the
adverse condition. It is advisable to start with either
pioneer species or species that occurs in the earlier
stage of succession.
DISCUSSION …A few species that are used in afforestation of the denuded hill slopes are
given below.
Temperate: Pinus wallichiana, Cedrus deodara, Juglans regia, Quercus
spp., Rhododendron spp., Alnus nepalensis.
Moist sub-tropical : Pinus roxburghii, Pinus patula, Alnu nepalensis,
etc.
Dry sub-tropical: Acacia modesta, Acacia catechu,, Prosopis juliflora,
Robinia pseudacacia, etc.
In chure hills: Schima wallichii, Acacia catechu, cassia siamia, Acacia
auriculiformis, Bamboos and grasses eg. Eulelioapsis binata etc.
DISCUSSION …
5. Method of raising plants: for the species mentioned
above, planting of nursery grown seedling is the best
but for some species direct sowing may be done.
6. Tending: weeding may have to carry out one or twice
in a year depending upon the local condition can be
continued for some years. However, weeding should be
done continuously so that the plants do not suffer from
isolation.
DISCUSSION …
7. Treatments of gullies: To check erosion, stone or
brush wood check dams are provided or masonry
check dams may be constructed where ever
necessary. When the dams get silted up the area is
planted with Agava, Ipomea, Arundo donax and
Vitex negundo.
4. CONCLUSION
There are many challenges to afforestation in
denuded hill slopes i.e. soil erosion, over grazing,
firing, construction of development activities etc.
Different factors must be considered i.e. Factors of
locality, Soil preparation activities, Choice of
species, Methods of raising plants, Tending
operation etc. while afforestation in denuded hill
slopes.
Conclusion …
Sites and choice of species are two major
factors must be considered while success in
afforestation activities in denuded hill slopes