Land use Change Assessment as An Effort To Mitigate Climate Change in Belawan Watershed Using Integrated Approach
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015
LAND USE CHANGE ASSESSMENT AS AN EFFORT TO
MITIGATE CLIMATE CHANGE IN BELAWAN WATERSHED
USING INTEGRATED APPROACH
1*
1
2 1 RAHMAWATY , NAJMATUL KHAIRAT AND ABDUL RAUF
Forestry Study Program, Faculty of Agriculture, University of Sumatera Utara, Medan 20155,
2 Indonesia, emailAgroecotechnology Study Program, Faculty of Agriculture, University of Sumatera Utara,
Medan 20155, Indonesia, email
*Corresponding author
ABSTRACT
Changes in the land cover are one of important issues in North Sumatra, especially in Belawan
Watershed. Belawan Watershed was located across Deli Serdang District and Medan City. In
order to mitigate climate change, this study aimed to evaluate the changes of land cover during
eleven years period (2000 to 2011) and to determine the main factor causing the change of land
cover in Belawan Watershed. The Geographic Information System (GIS) with overlay technique
was used to analyze land cover changes and the Analytical Hierarchy Process (AHP) with
questionnaires and interviews were used to determine the cause of changes and the factors
driving the changes in land cover (integrated approach). Field observations were also made to
the biophysical conditions due to changes in land cover. The results showed that during eleven
years, extensive changes in land cover were the greatest in dry land farming mixed shrubs that
became dry land agriculture. Economic factors were the main cause of changes, followed by
social factors and ecological factors. Economic criteria selected by respondents as the most
important priority for activities in Belawan Watershed could not be separated from economic
activities that were aligned with spatial development. This certainly influenced the basis of
economic or financial considerations to convert agricultural land into non-agricultural use either
for residential, offices, and other facilities. In order to mitigate climate change in Belawan
Watershed, it is expected that the role of all stakeholders, especially local governments should
be improved so that changes in land cover can be minimized.”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015
2000-2011 periods is necessary. Among 83% of the total watershed Belawan is located in Deli Serdang district. This Belawan Watershed in Deli Serdang has the largest in district in Kutalimbaru with total area almost 27% out of 83% of the total watershed Belawan Deli Serdang. Meanwhile, the smallest area is in Namorambe District with of the total area. only 0.02% (5 ha)
Analysis of Land Cover Changes in Belawan Watershed used land use data from 2000 and 2011 (11 years period). The data were obtained based on the results of previous year’s data available in the Central Forest Area Consolidation (BPKH), Ministry of Forestry, i.e. data from 2011 can be used as a comparison to each interval data from the last five to six years. Analysis of extensive changes in land cover in Belawan Watershed in 2000-2011 can be obtained by comparing the area and the changes that occurred in 2000 and 2011. Land use changes in Medan City are important to be studied because the land use change will affect the climate change in Medan City. In North Sumatra, research on land use had been carried out (Rahmawaty
et al., 2011; Onrizal, 2010). This study aimed to analyze land cover changes in
Belawan Watershed from 2000 to 2011 and to analyze the factors causing land cover changes in Belawan Watershed.
MATERIALS AND METHODS
This study was conducted from March to August 2013 in Belawan Watershed (Fig.1). Data collection was conducted from March to April 2013, and the data analysis was conducted from May to August 2013. Data processing was performed at the Laboratory of Integrated Forest Management Department of Forestry, Faculty of Agriculture, North Sumatra University.
Belawan Watershed is located across Deli Serdang District and Medan City. The total area of Deli Serdang is 83 % of the watershed area Belawan and 10.04 % of the total area of Medan. Sub-districts included in the region of Deli Serdang District of Hamparan Perak, Kutalimbaru, Namorambe, Pancurbatu, Sibolangit, and sunggal. The area of Medan are Medan District of Helvetia, Medan Belawan, Medan Marelan , Medan Selayang , Sunggal Medan and Medan Tuntungan. The area of each district included in the watershed areas Belawan. Belawan Watershed is located mostly
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015 Belawan Watershed Map
Figure 1: Study site map The Geographic Information System (GIS) with overlay technique was used to analyze land use changes. The Analytical Hierarchy Process (AHP) with questionnaires and interview was used to determine the cause of changes and the
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015
Belawan Watershed needs to be regulated by government agencies to maintain ecosystem sustainability.
Land cover in Watershed Belawan can generally be classified into twelve types i.e. primary dry forest, scrub, plantation, dry land agriculture, dry land agriculture mix, settlement, clearing, body of water, secondary mangrove forests, ponds, shrub swamps and rice paddies. Table 1 lists broad types of land cover in 2000, and 2011. Changes of land cover classification data from 2000 to 2011 was obtained by comparing the land cover in 2000 and 2011 to obtain land cover of the predetermined interval. Furthermore, the classification results provided data of any changes in the area to obtain land cover change from 2000 and 2011, which was quite extensive (Table 1).
Tabel 1. Land cover types changes in Belawan Watershed in 2000-2011
Changes occurred between 2000 and
in 2000 in 2011
Land cover types2011 (ha) (ha) (Ha) Dry land-primary forest 506.11 506.11 Shrubs 569.61 569.61 Plantation 3,847.96 3,902.45 +54,49 Dry land farming/ agriculture 9,183.42 23,512.78 +14.329,36 Settlement 4,466.12 4,466.12 Open land 668.86 411.18 -239,24 Water body 292.81 292.81 Secondary mangrove forest 757.77 690.55 -67,22 Fishpond 2,267.27 2,702.05 +434,78 Shrubs mixed bush 1,746.94 1,344.46 -402,46 Dry land farming mixed shrubs 14,857.79 -14.857,78 Rice field 1,070.68 1,837.19 +766,51 Total 40,235.36 40,235.36 Table 2. Matrix of extensive changes in land use in Belawan Watershed from 2000 to 2011
Total in
Land cover in 2011 (ha)
2000 DryDry land Open Water Land cover Plantation land-
Secondary Shrubs farming Shrubs land body Fishpond primary Dry land mangrove mixed mixed in 2000
Settlement Rice field (ha) forest farming/agriculture forest bush shrubs
(ha) Dry land - primary forest 506.,11
506.11 Shrubs 569.61 569,61 Plantation 3,820.06
27.89 3,847.95 Dry land farming/ agriculture
8,706.59 476.81 9,183.41 Settlement
4,466.12 4,466.12 Open land
18.43 360.73 289.69 668.86 Water body
292.81 292.81 Secondary mangrove forest
690.55 67.22 757.77 Fishpond
2,267.26 2,267.26 Shrubs mixed bush
63.95 338.51 1,344.46 1,746.92 Dry land farming mixed shrubs 14,778.28 50.454
29.05 14,857.78 Rice field 1,070.68 1,070.68
Total in 2011 506.11 569.61 3,902.44 23,512.78 4,466.12 411.18 292.81 690.55 2,702.04 1,344.46 1,837.19 42,502.62 Changes (ha) +54.49 +14,329.36 -239.24 -67.22 +434.78 -402.46 -14,857.78 +766.51 Changes (%) 1.42 164.58 -66.32 -9.73 19.17 -29.93
71.59 Map of Land Use Changes in Belawan Watershed in 2000-2011
Figure 2. Map of Land Use Changes in Belawan Watershed in 2000-2011
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015
Table 2 showed that 27.89 ha of plantation in 2000 changed into dry land farming/agriculture in 2011, 18.43 ha of open land in 2000 changed into plantation in 2011, 67.22 ha of secondary mangrove forests in 2000 changed into fishpond in 2011, 338.51 ha of shrub mixed bush in 2000 changed into fish pond in 2011, 63.95 ha of shrub mixed bush in 2000 changed into plantation in year 2011, 29.05 ha of dry land farming mixed shrubs in 2000 changed into fishpond in 2011, and 50.45 ha of dry land farming mixed shrubs in 2000 changed into open land in 2011. Map of land cover changes can be seen in Figure 2.
The dominant changes of land area from 2000 to 2011 occurred on dry land farming/agriculture, which is consistent with the statement by Irawan (2005) and Rahmawaty et al., (2011). Dry-land farming/agriculture land types are mostly located in the upstream and downstream parts of the watershed i.e. in Belawan Kelambir Lima village of Medan Marelan Subdistrict and Kelumpang village of Pancur Batu Subdistrict. The society in the upstream part of Belawan Watershed mostly practiced dryland farming, especially sugar cane, corn crops, and vegetables (Fig. 2).
Watershed conditions were still well maintained and clean which attracted the surrounding community to conduct bathing and washing activities on the bank of the river (Fig. 3).
Figure 3. The condition of the upstream part of Belawan Watershed
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015
and should have the consistency of less than 10% or 0.10 to be considered correct or accurate.
The weighted value was then recapitulated and ranked to obtain overall conclusions on factors causing land cover changes in Belawan Watershed. Table 3. Criteria Considered to Cause Land Cover Change
Criteria Geometric Average Priority Rank Social
0.20
0.28
2 Ecology
0.37
0.25
3 Economy
0.23
0.46
1 Total
0.81
1 The most dominant factor leading to land cover changes in Belawan
Watershed was the economic criteria. According to Rustiadi (2001) in order to support higher economic growth, land resources management was often tactless and did not consider sustainability aspects (for short term). This study showed that if there is no efforts conducted to manage the land cover change, Belawan Watershed sustainability will be threatened and the resources of high-quality land will experience reduction and people will continue to depend on land resources in Belawan Watershed resulting to low quality of land. Education is among factors influencing people on how to sustainably utilize the existing land in Belawan Watershed. Most residents in the area of Belawan Watershed are in the elementary and secondary levels (Syahrial, 2009). In addition to educational factors, socio-cultural factors are also important to be considered in land management. Komarsa (2001) reported that socio-cultural factors are concerned with the educational background, occupation, age, motivation and perception, views or attitude to life and customs which greatly affects the changes occurred in Belawan Watershed. Economic factors are the dominant factor causing the change in land cover and can be anticipated by providing alternatives to reduce the damage in Belawan Watershed. Criteria and alternatives offered are the result of interviews on ten respondents in order to obtain the respondents’ assessments on the six alternatives offered to each respondent (Table 4).
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015
alternative to be offered (Table 4). Data summary will be used to determine alternatives to manage the factors causing land cover changes in Belawan Watershed.
Alternatives offered in solving problems of land cover change in Belawan Watershed were zoning, spatial planning, land acquisition, manufacture of infiltration wells, socialization, and law enforcement. Zoning is a barrier zone that essentially stipulated in the laws. Zoning is associated with the land use itself as a protected zone in conservation zone rules in the law firm. Spatial planning is more directed to local regulations that have been made and are planned based on region for each region. Land acquisition alternative was offered because watershed area must have 30% forest area of the total area as green open space in Belawan watershed.
The upstream part of Belawan Watershed contained sand mining along the riverbanks, therefore, alternative was offered to make infiltration wells to prevent erosion and flooding. Socialization leads to the liveliness of the public and to maintain public awareness of watershed areas. Law enforcement alternative was offered to guard the strictness of the rules that bind the community when breaking the existing policies. Hall of Watershed Management (BP DAS) has already publicly announced that the watershed areas must have 30% vegetation cover to be regenerated as a watershed. Among socialization activities carried out was planting one billion trees through collaboration with the Indonesian Heritage Foundation preceded by socializing greening plan to all communities in the Belawan Watershed covering 8 villages.
Business approach to the community has been done, but the people who live in the watershed areas are still conducting land conversion. There should be a decisive participation from government officials such as district head of each region, so that they can monitor the state of the watershed according to the function. There should also be firm enforced rules in the society as a tool to remind the community on how important it is to sustainably utilize the Belawan Watershed.
CONCLUSIONS
During eleven years period (2000- 2011), the extensive land use changes occurred on dry land farming/agriculture, followed by changes in secondary mangrove forest to become fishpond. The dominant factors causing land use changes in the Belawan Watershed based on AHP analysis was economy, while the law enforcement was the first rank as alternative offered to solve the land use change issue in Belawan
”, SEAMEO BIOTROP, Bogor-INDONESIA, 12-13 OCTOBER 2015 Rahmawaty, TR Villanueva, MG Carandang. 2011. Participatory Land Use Allocation.
LAP Lambert. Saarbrucken, Germany. Rustiadi. 2001. Dinamika Spasial Perubahan Penggunaan Lahan dan Faktor - Faktor
Penyebabnya di Kabupaten Serang Provinsi Banten. Tesis. Institut Pertanian Bogor. Bogor. Syahrial, R. 2009. Analisis Peruntukan Lahan Daerah Aliran Sungai (DAS) Belawan Kaitannya dengan Tata Ruang. USU Press. Universitas. Medan. Wijaya CI. 2004. Analisis Perubahan Penutupan Lahan Kabupaten Cianjur Jawa Barat Menggunakan Sistem Informasi Geografis. Skripsi. Institut Pertanian Bogor.
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