Andriana E. Sanam, Muhammad SM Nur, Jakobis Johanis Messakh |
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633
ALTERNATIVE MANAGEMENT OF RIVER WATERSHED WITH
BATULESA METHOD FROM ENVIRONMENTAL ASPECTS
Andriana E. Sanam
1
, Muhammad SM Nur
2
, Jakobis Johanis Messakh
3
Master of Environmental Science Students, Nusa Cendana University
1
, Environmental
Science Lecturer, Nusa Cendana University,
2,3
Indonesia
emeliasanam47@gmail.com, mahmuddinundana@gmail.com, yapmessakh@gmail.com
KEYWORDS
Meto Batulesa
Watershed, Actual
Erosion, Erosion
Tolerance,
Alternative
Conservation
ARTICLE INFO
Accepted:
April, 26
th
2022
Revised:
May, 7
th
2022
Approved:
May, 12
nd
2022
ABSTRACT
The research was conducted in the Meto Batulesa watershed, with a
watershed area of 8,968 ha, located between two regencies, Kupang
and Kupang city. The purpose of this research is to calculate the actual
erosion rate and tolerable erosion, so that conservation alternatives can
be found. Based on the map of land units, there are 19 land units that
are then used for soil sampling, slope, observation of soil management
and soil conservation. The sampling method used purposive sampling,
the data taken to calculate erosion estimates using the Universal Soil
Equation (USLE) method, while the erosion tolerance used the
concept of equivalent depth and resource life based on (Hammer 1981)
and (Arsyad 2010). The results of the study show that the highest
actual erosion value of 225.68 tons/hectare/year and the lowest is 2.78
tons/hectare/year. The value of erosion tolerance among 19 land units,
in which are 10 land units is above the erosion tolerance so that they
require alternative management, while 9 of them are without
conservation. Alternative management in the form of modifications to
the values of C and P include 1. Terrace Gulud: Corn + Beans + Mulch
of Plant Remnants, 2. Corn + Soybean with rotational cropping pattern
+ mulch of crop residues, 3. Bench terrace + corn cassava/soybean, 4.
Secondary forest and 5. Primary forest.
INTRODUCTION
Efforts to overcome critical land in NTT by the government in carrying out conservation
in NTT covering an area of 3,615 Ha/year so that the deviation between the rate of degradation
and planting efforts reaches 4:1, if the deviation will increase sharply to 8:1 then the percentage
of buildings and plants only reaches 50% of amount planted (Nama et al, 2016). Based on these
data, it is necessary for conservation from the government to increase it to 50%again for
maximum.
According (Kupang Department of Environment and Forestry, 2019), incope Land
degradation in the watershed in NTT is highly dependent on the integrated movement of all
sectors and is supported by the availability of accurate and actual spatial data from competent
data trustees. The cause of land degradation, namely the existence of forest land fires is one of
the important inputs for watershed degradation, so it is necessary to arrange and regulate
relevant regional regulations as well as strict sanctions against perpetrators of land and forest
fire.
Volume 3, Number 7, May 2022
e-ISSN: 2797-6068 and p-ISSN: 2777-0915
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The real impact of degradation is erosion. One of the methods used to calculate the
erosion rate is the Universal Soil Equation (USLE) method. This method is an erosion model
designed to predict the average soil erosion in the long term from a farming area with a certain
cropping and management system. The predicted form of erosion is sheet or groove erosion,
but cannot predict deposition and does not take into account sediment yields from erosion of
ditches, riverbanks, and riverbeds (Arsyad 2010). According to (Wischmeier & Smith, 1978),
factors that affect the USLE equation are land use which plays a large role and is accompanied
by conservation actions that will be carried out.
Several methods of vegetative soil conservation techniques are any use of plants or
vegetation, or plant remains as a medium for protecting the soil from erosion, inhibiting surface
runoff, and increasing soil moisture content, as well as improving soil properties, both physical,
chemical and biological properties (Mulyandari & Susila, 2020). Mechanical soil conservation
techniques or also known as civil engineering are efforts to cultivate agricultural land in
accordance with the principles of soil conservation as well as water conservation. This
technique includes mounds, mound terraces, bench terraces, individual terraces, credit terraces,
contour bunds, garden terraces, stone rows, and stone terraces. Specifically for water harvesting
purposes, mechanical conservation techniques include the construction of water catchment
structures, rorak, and dams (Dariah et al, 2004).
One of the cross-regency watersheds on the island of Timor is Meto Batulesa. Meto
Batulesa watershed with an area of 8,961 Ha which is located between two regencies, namely
Kupang Regency and Kupang City. Based on the biophysics of the Meto Batulesa watershed,
the average rainfall at 3 rain stations is Naioni 1,704.4 mm/year, Oenesu 1,412.20 mm/year,
and Bakunase 1,294.4 mm/year, accompanied by the type of soil rensina which is susceptible
to hazards. Erosion and the slope ranges from 15-25% which is relatively steep and is supported
by the use of land in the form of secondary dry land forest, dry land and shrub agriculture, and
shrubs and open land. There is a change in land use to settlements and the shifting cultivation
system practiced by farmers in the upstream area as well as the existence of former manganese
mining by the community in the past. Upper Meto Batulesa watershed. This is thought to have
caused erosion that occurred greater than the rate of soil formation or erosion that was tolerated.
If the land management system in the upstream part of the Meto Batulesa watershed continues,
it will certainly create new critical lands, while according to (RPJM-12 Kupang City, 2016),
Naioni Village and Fatukoa Village are included in the protective area for the lower area with
the aim of maintaining and revitalizing water catchment areas or areas that function
hydrologically so as to ensure the availability of water resources.
The objectives of this research are to calculate the actual and tolerable erosion in the
Meto Batulesa watershed, to provide conservation recommendations based on estimates of
actual erosion and erosion tolerance in the Meto Batulesa watershed.
RESEARCH METHOD
The research location is located in the Meto Batulesa watershed, part of which is in the
Kupang district and also the city of Kupang with a watershed area of 8. 967.66 Ha. Research
(starting from May – June 2021). Field research for soil sampling using purposive sampling
methodor adjusted to the purpose so that the Staratifield Random Sampling method is used so
that it is distinguished from slope, land cover and soil type so that 19 land units were obtained.
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The data collection carried out in this study used secondary data in the form of rainfall
data from the Kupang BMKG, soil types from the Kupang district soil type map, Kupang
district land cover map and slope map. Primary data in the form of soil sampling, soil profile
observations, soil order determination, plant management observations and conservation
actions.
The variable in this study is the rainfall in the Naioni, Bakunase, Oenesu areas. analyzed
using the Bols 1978 formula to obtain the erosivity of rain. The K value was obtained from
field and laboratory observations and adjusted to the K value based on (JICA, 1995). CP value
used is based on (Abdurrahman. et al., 1984), and Arsyad 2000 while for erosion tolerance
based on the age of use of the soil and the effective depth of the soil, field observations were
carried out to determine the orders and sub-orders of soils with a taxonomy book guide
(Department of Agriculture, 2015) so that the calculation of erosion tolerance is carried.
RESULTS AND DISCUSSION
a. Land
Of the 19 land units in the Meto Batulesa watershed, 2 types of soil were found, namely
inceptisol soil and entisol soil.
Table 1 Soil Types in the Meto Batulesa Watershed
Sample
No. Unit
Land
Type of soil
USDA
Sub
Order
Mark
K
4
I
Inceptisol
Tropepts
0.07
1
II
Inceptisol
Tropepts
0.07
12
III
Entisol
Orthents
0.32
4
IV
Inceptisol
Tropepts
0.07
9
V
Inceptisol
Tropepts
0.07
8
VI
Entisol
Orthents
0.32
3
VII
Inceptisol
Tropepts
0.07
13
VIII
Inceptisol
Tropepts
0.07
12
IX
Entisol
Orthents
0.32
11
X
Inceptisol
Tropepts
0.07
14
XI
Inceptisol
Tropepts
0.07
7
XII
Inceptisol
Tropepts
0.07
2
XIII
Inceptisol
Tropepts
0.07
6
XIV
Inceptisol
Tropepts
0.07
14
XV
Inceptisol
Tropepts
0.07
10
XVI
Inceptisol
Tropepts
0.07
15
XVII
Inceptisol
Tropepts
0.07
14
XVIII
Inceptisol
Tropepts
0.07
12
XIX
Entisol
Orthents
0.32
Source: Research results and JICA, 2005
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b. Slope
Table 2 Slope Class of Meto Batulesa Watershed
No
Slope class
Classification
Area_Ha
%
1
0 - 8%
Flat
3,417.52
38.11
2
8 – 15%
Sloping
3,996.75
44.57
3
15 – 25%
Slightly Steep
1553.39
17.32
4
25 -45%
Steep
-
5
> 45
Very Steep -
Total
8,967,66
100
Source: Based on Slope Class Map of Meto Batulesa watershed
Class slopes I is an area with a slope of 0-8% with a percentage of 38.11% of the total
area of the entire research area. In this slope class the erosion hazard is relatively smaller. This
is because the rain water that falls will not immediately flow in the form of surface runoff but
will still be stuck on the ground surface and even infiltrate into the ground.
Class II is a slope with a slope of 8 -15% with an area percentage of 44.57% of the total
area of the entire research area. The rate of erosion that occurs in this slope class is relatively
higher than that of slope class I (if other erosion factors are the same) due to an increase in
surface runoff which results in an increase in the strength to erode and transport soil particles.
For slope class III, a slope with a slope of 15-25% or a slightly steeper area of 17.32% of
course the amount of erosion will be greater than the second slope class because it is included
in the steep category.
c. Land Cover
Table 3 Table of C . Values
No
C Nilai Value
Sample
1
0.32 (tree without bush)
Sample 1
2
0.2 (Mixed Garden)
Sample 2
3
0.32 (tree without bush)
Sample 3
4
0.32 (tree without bush)
Sample 4
5
0.32 (tree without bush)
Sample 5
6
0.32 (tree without bush)
Sample 6
7
0.32 (tree without bush)
Sample 7
8
0.01 (undisturbed bush)
Sample 8
9
0.01 (undisturbed bush)
Sample 9
10
0.3 (shrub)
Sample 10
11
0.3 (shrub)
Sample 11
12
0.2 (mixed garden)
Sample 12
13
0.01 (undisturbed bush)
Sample 13
14
0.01 (undisturbed bush)
Sample 14
15
0.01 (undisturbed bush)
Sample 15
Source: Author's research results 2021
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d. Rainfall
The R value is taken from the average monthly rainfall for 5 years and then calculated
using the Bols formula (1978) and then. The classification is then used to determine the R value
in the Meto Batulesa watershed with high rainfall classification, namely Naioni rain post,
moderate rain classification, Oenesu rain post and low for Bakunase rain post.
Figure 1 Map of Land Units in the Meto Batulesa watershed
e. Actual Erosion Value and Erosion Hazard Level
Table 4 Estimation of Actual Erosion in the Meto Batulesa Watershed
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From table 4, it can be seen that the erosion calculation using the USLE formula is the
highest erosion on land unit 19 and the lowest on land unit 5. The high erosion rate on land unit
19 is caused by the length of the slope of 50 meters and landslides were found in that land unit.
Table 5 Erosion Rates in the Meto Batulesa Watershed
No.
Erosion Class
A (Erosion)
Tons/Ha/Year
Land area
1
Class I
19.17
1,535,48
2
Class II
-
-
3
Class III
25,72
6594.07
4
Class IV
250,22
795.91
5
Class V
371.332
34.39
Source: 2021 data processing
From Table 5 the level of erosion hazard is obtained from the classification between soil
solum and the amount of erosion per year so that the erosion hazard level (TBE) is included.
The erosion hazard level in the Meto Batulesa watershed consists of four classes, including
class I erosion, which is mild with the amount of erosion 19.17 tons/ha/year and the land area
is 1,535.48 ha, the type of soil is inceptisol with a soil solum above 90 cm and the vegetation
is shrubs. undisturbed, so that the rain that falls can be held in the bushes and there is little
chance for surface runoff because the permeability is fast, and is on a slope of 0-8% flat to
undulating 8-15% so that this is what causes erosion in this category. light.
For the medium category (III) erosion estimation is 25.72 tons/ha/year with a land area
of 6.594.07 ha. The vegetation is in the form of undisturbed shrubs, trees without shrubs, and
shrubs.
The level of erosion hazard with heavy category (IV) erosion value is 250.22 tons/ha/year
with a land area of 795.91 ha, vegetation in the form of mixed gardens and trees without shrubs,
as well as shrubs. Areas of heavy erosion are around Fatukoa, Oenesu and Naioni.
The classification of the erosion hazard level (V) is very heavy with an erosion estimate
of 371.332 tons/ha/year with a land area of 34.39, the vegetation in the form of mixed gardens
and the soil types are entisols and solum soils of 30-60 cm. The land use is in the form of open
land, with a gentle to slightly steep slope. If the land cover is open land because there is no
barrier to resist the flow of the soil surface, then erosion will certainly occur and is included in
heavy erosion so that it is a priority scale for conservation.
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Table 6 Erosion Tolerance Comparison
LAND
UNITS
SOIL
ORDER
SUB-
ORDER
F
K
Effective
Depth
(mm)
Depth
equivalent
AGE
USAG
E
(year)
T
value
I
Inceptisol
Tropepts
1
600
600
400
1.5
II
Inceptisol
Tropepts
1
600
600
400
1.5
III
Entisol
Orthents
1
600
600
400
1.5
IV
Inceptisol
Tropepts
1
600
600
400
1.5
V
Inceptisol
Tropepts
1
600
600
400
1.5
VI
Entisol
Orthents
1
600
600
400
1.5
VII
Inceptisol
Tropepts
1
600
600
400
1.5
VIII
Inceptisol
Tropepts
1
800
800
400
2
IX
Entisol
Orthents
1
600
600
400
1.5
X
Inceptisol
Tropepts
1
600
600
400
1.5
XI
Inceptisol
Tropepts
1
900
900
400
2.25
XII
Inceptisol
Tropepts
1
900
900
400
2.25
XIII
Inceptisol
Tropepts
1
900
900
400
2.25
XIV
Inceptisol
Tropepts
1
600
600
400
1.5
XV
Inceptisol
Tropepts
1
900
900
400
2.25
XVI
Inceptisol
Tropepts
1
600
600
400
1.5
XVII
Inceptisol
Tropepts
1
600
600
400
1.5
XVIII
Inceptisol
Tropepts
1
900
900
400
2.25
XIX
Entisol
Orthents
1
600
600
400
1.5
Source: Data Processing 2021
The calculation of erosion tolerance is needed to determine the tolerance limit of the
soil to be used. The method used in calculating the T value uses the concept of equivalent depth
and resource life. The equivalent depth is the depth of the soil after it has been eroded.
Productivityreduced by 60% of the uneroded soil productivity. The value of the soil
depth factor based on the sub-order of the soil multiplied by the effective depth of the soil will
get the equivalent depth while the effective depth is the depth of the soil to a layer that inhibits
the growth of plant roots. The equivalent depth is then divided by the useful life of the soil and
then converted to tons/ha/year.
Comparison of actual erosion and tolerable erosion is very important to know because
it has an important purpose as a determinant of whether conservation is needed or not. Based
on this comparison, the A<EDP value is in l land units (1, 2, 3, 4, 6, 7, 9,10, 13, 15 and 19)
which means that conservation is necessary. An alternative to reducing actual and modified
erosion is the value of crop management factors or CP .
For the EDP value > A, it is in the land unit (5, 8, 11, 12, 15, 16, 17, and 18) so it does
not require conservation but still maintains the carrying capacity of the environment.
f. Conservation Criteria
Land physical parameters
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Table 7 Land Physical Parameters
Climate
Rainfall
1,136 mm Year
Rainy day
103 days
Land
physiography
Land slope
0-8 Plains
15-25 Steep
Place Elevation
331 masl-350 masl
Geomorphology
Landscape
Land
appearance
(Relief)
Lowland -
hills
Rock
distribution
Small Stone- Big Rock
Root system
depth
80-90 cm
Land
Type of soil
Inceptisols and Entisols
Physical
properties
Texture
- Sandy Clay
- loamy sand
Structure
- Angular lump
Permeability
28.5-32.57 cm/Hour
Consistency
Sticky wet soil, if the two fingers are stretched, the soil
is left on both fingers, Moist soil: Slightly plastic can
take the form of twists. Dry Soil: Hard to withstand
pressure
Wet soil: Slightly sticky, when both fingers are
removed, some soil is left on one finger.
moist:Slightly plastic, can be in the form of soil
rotation, soil mass is easily deformed.dry :Hard :
resistant to pressure, soil mass can be broken by hand
Level (BO)
1.70 and 09
Hydrology
Erosion
55,553 tons/ha/year and 150,875 tons/ha/year
Source: Data Processing 2021
g. Forest landscape management indicators
Table 8 Forest landscape management indicators
Indicator
Criteria
Parameter
Information
Social
culture
Social
culture
Total population
divided
with an area.
the higher the population, the
higher the pressure on land
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custom
customs
violators are fined
and reprimanded by
the traditional leader
Customs regulate behavior
will have an impact on the
success of conservation
ecology
Erosion
Estimation of actual
erosion
The lower the land cover, the
erosion will occur
economy
Level
Well-being
Income per capita
the higher the level of
community income from the
existence of the forest, the
greater the damage to the
forest
Source: Data Processing 2021
Based on field research on the economy, ecology and socio-culture of the Naioni
community with a population of 1,112 people and an area of 3500km2 differenceBetween the
total population and the area is the population density per kilometer so that it is obtained 1.59
km2, meaning that every 1.59 km2 distance is inhabited by 1 person so that the population
density in Naioni Village is not too dense.
LevelThe average education level of the Naioni community is still low because some
people only have elementary school education and some have not even finished elementary
school. The customs used if there is a violation, the consequence is to pay a fine and be
reprimanded by the customary leader.
ParameterThe ecology used is the level of erosion based on the estimation of actual
erosion which is in the heavy and very heavy category due to the land cover in the form of trees
without shrubs. Based on the average per capita income level of Kupang City of 3.05 million
per month in 2020(Kupang City Economic Indicators, 2020).
h. Conservation Alternatives on offer
Of the 19 land units, 10 of them require conservation, 9 do not require conservation
because their values are below the erosion tolerance. As for the management of the Meto
Batulesa watershed, 5 alternative scenarios are given, including:
Table 9 Erosion Tolerance Value
Unit
Land
cover
Land
Representativ
e Sample
Order
Land
Sub
Order
T
valu
e
Erosion
A:
T
I
Secondary
Dryland Forest
4
Inceptisol
Tropepts
15
37.10
A >
T
II
Secondary
Dryland Forest
1
Inceptisol
Tropepts
15
57.92
A >
T
III
Dryland and
Shrub Farm
12
Entisol
Orthents
15
41.78
A >
T
IV
Dryland and
Shrub Farm
4
Inceptisol
Tropepts
15
37.10
A >
T
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VI
Shrubs
8
Entisol
Orthents
15
21.85
A >
T
VII
Shrubs
3
Inceptisol
Tropepts
15
53.48
A >
T
IX
Open Ground
12
Entisol
Orthents
15
64.49
A >
T
X
Open Ground
11
Inceptisol
Tropepts
15
19.50
A >
T
XIII
Shrubs
2
Inceptisol
Tropepts
22.5
138.56
A >
T
XIX
Open Ground
12
Entisol
Orthents
15
194.02
A >
T
Source: Author's Analysis 2021
1. Terrace Gulud: Corn + Beans + Mulch of Plant Remnants
In land unit 3 in the form of entisol soil, found in Oenesu village with rainfall of 1,704
mm/year and land unit 4 in Naioni subdistrict with the land cover being dry land and
shrubland agriculture, with an average annual rainfall of 1,412 mm/year. The soil is inceptisol
soil. The alternative conservation offered is in the form of a mound terrace with plant
modifications in the form of corn, beans and plant residue mulch. If the alternative is given,
the value of the management factor (CP) used is 0.01 so that the erosion value for land unit 3
becomes 146 tons/ha/year and for land unit 4 erosion per year becomes 0.92
tons/hectare/year. In land unit 9 the land cover is open land with an R value of 916.84 K
value 0.32 LS 0.01 and CP 0.01 so that it has an erosion value of 1,
Table 10 Erosion Value After Modification
Unit
Land
Land Cover
R
K
LS
CP
A2 (tonnes/ha/year)
III
Dryland and Shrub Farm
916.83
0.32
0.71
0.01
1.25
IV
Dryland and Shrub Farm
916.83
0.07
1.81
0.01
0.70
IX
Open Ground
916.83
0.32
1.10
0.01
1.93
Source: Author's Analysis 2021
2. Corn + Soybean intercropping pattern + crop residue mulch
In land units 3 and 4, the types of land cover are secondary dry land agriculture and
shrubs, so that the conservation provided is in the form of corn plus soybeans with an
overlapping crop pattern and added mulch for crop residues.
The cropping pattern uses overlapping crops, namely the land is planted with two or
more plants with harvest time settings, so that after harvesting mulch the rest of the plants are
spread around the soil and cover the soil so that if rainwater falls there is no runoff so that it
can minimize the erosion value. The results of the calculation of erosion according to table
4.23 alternative erosion values are low, resulting in an erosion value of 6.49 tons/hectare/year
and 3.60 tons/hectare/year theoretically the erosion value is reduced.
Table 11 Erosion Value After Modification
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Unit
Land
Land Cover
R
K
LS
C
P
A2
(tonnes/ha/year)
III
Dryland and
Shrub Farm
916.83
0.32
0.71
0.09
0.36
6.49
IV
Dryland and
Shrub Farm
916.83
0.07
1.81
0.09
0.36
3.60
Source: Author's Analysis 2021
3. Terrace Bench + corn cassava / cassava.
For the third scenario, alternative bench terraces are provided in the form of corn and
cassava. The bench terrace is made to reduce the length of the slopes on land units 3 and 4,
the slope length reaches 50 meters, if the bench terrace is applied, the length of the slope will
decrease so that the erosion that occurs will be smaller.reducefrom41.78 tons/hectare/year
reduced to 6.49 tons/hectare/year. In the fourth land unit, it was reduced from 37.10
tons/hectare/year to 1.30 tons/hectare/year.
Table 13 Erosion Value After Modification
Land
Unit
cover
Land
R
K
LS
C
P
A2
(tonnes/ha/yr)
III
Dryland and
Shrub Farm
916.83
0.32
0.71
0.06
0.20
2.34
IV
Dryland and
Shrub Farm
916.83
0.07
1.81
0.06
0.20
1.30
Source: Author's Analysis 2021
4. Secondary Forest
The fourth scenario is conservation from secondary dry land forest, shrubs and open
land to secondary forest, the change in the CP value is 0.01 so the erosion value is getting
smaller.
Field observations at the research location found that there were factors supporting the
occurrence of erosion, including slope length, vegetation cover and soil type
Table 14 Calculation of alternative secondary forest conservation
LAND
UNITS
Land Cover
Representati
ve Sample
R
K
LS
CP
A2
(tonnes/ha/yea
r)
I
Secondary
Dryland Forest
4
1112.1
0
0.0
7
1.81
0.0
1
0.70
II
Secondary
Dryland Forest
1
1112.1
0
0.0
7
2.33
0.0
1
0.91
VI
Shrubs
8
916.83
0.3
2
7.45
0.0
1
10.93
VII
Shrubs
3
916.83
0.0
7
2.60
0.0
1
0.84
XIII
Shrubs
2
1112.1
0
0.0
7
8.90
0.0
1
3.46
[ ALTERNATIVE MANAGEMENT OF RIVER WATERSHED
WITH BATULESA METHOD FROM ENVIRONMENTAL
ASPECTS]
644
http://devotion.greenvest.co.id |Andriana E. Sanam, Muhammad SM Nur, Jakobis
Johanis Messakh
Vol. 3, No. 7, May 2022
XIX
Open Ground
12
916.83
0.3
2
3.31
0.0
1
4.85
IX
Open Ground
12
916.83
0.3
2
1.10
0.0
1
1.61
X
Open Ground
11
916.83
0.0
7
1.01
0.0
1
0.32
Source: Author's Analysis 2021
5. Primary Forest
On the land cover of secondary dryland forest and shrubs, the conservation
alternatives given are primary forest so that the modified value is the CP value to 0.001 so
that it reduces the value of the erosion rate.
Table 15 Calculation of alternative primary forest conservation
Land unit
Land Cover
R
K
LS
CP
A2(tons/ha/year)
I
Secondary
Dryland Forest
916.83
0.07
1.81
0.001
0.12
II
Secondary
Dryland Forest
1112.10
0.07
2.33
0.001
0.18
VI
Shrubs
916.83
0.32
7.45
0.001
2.19
VII
Shrubs
916.83
0.07
2.60
0.001
0.17
XIII
Shrubs
1112.10
0.07
8.90
0.001
0.69
XIX
Open Ground
916.83
0.32
3.31
0.001
0.97
IX
Open Ground
916.83
0.32
1.10
0.001
0.32
X
Open Ground
916.83
0.07
1.01
0.001
0.06
Source: Author's Analysis 2021
CONCLUSION
1. The highest actual erosion of 225,672 tons/ha/year was found in 19 land units in the Sumlili
area, the lowest was 2,676 tons/ha/year in the Oenesu area. Calculation of erosion tolerance
from 19 land units, 9 of which are below the erosion tolerance while 10 are above the erosion
tolerance, and the erosion hazard level for the very heavy erosion category (V) there are 2
land units included in the heavy category (IV) 6 land units, the Medium category (III) ) 7
land units, and very light (I) 3 land units for the light category (II) Not found in the Meto
Batulesa watershed.
2. Based on the physical condition of the Meto Batulesa watershed, the management
alternatives offered include, 1. Terrace Gulud: Corn + Beans + Mulch of Plant Remnants,2.
Corn + Soybean with rotational cropping pattern + mulch of crop residues, 3. Bench terrace
+ corn cassava/soybean, 4. Secondary forest and 5. Primary forest.
[ ALTERNATIVE MANAGEMENT OF RIVER WATERSHED
WITH BATULESA METHOD FROM ENVIRONMENTAL
ASPECTS]
Andriana E. Sanam, Muhammad SM Nur, Jakobis Johanis Messakh |
http://devotion.greenvest.co.id
645
Vol. 3, No. 7, May 2022
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Copyright holders:
Andriana E. Sanam, Muhammad SM Nur, Jakobis Johanis Messakh (2022)
First publication right:
Devotion - Journal of Research and Community Service
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