Changes in land use and land cover in forest areas in Bener Meriah and Aceh Tengah Districts, Indonesia

This research aims to obtain information regarding land use and land cover (LULC) changes in forest areas in Bener Meriah and Aceh Tengah Districts in 2000-2021, especially on the loss and gain of forest areas, and conversion between land cover classes. We used Landsat 5 (TM) satellite imagery data recorded in 2000 and 2006, and Landsat 8 (OLI) satellite imagery recorded in 2014 and 2020/2021 on path/row data, namely 130/57. The classification processes of LULC included the determination of training areas, supervised classification, and accuracy assessment. The LULC in Bener Meriah and Aceh Tengah districts are dominated by primary dryland forest and secondary dryland forest 250348.45 ha (53.65%) and 103153.16 ha (22.11%), respectively; other land covers, plantation forest 45601.12 ha (9.77%) and shrubs 314722.96 ha (6.74%). However, there is a very significant increase in mixed dryland agriculture areas, from 3186.33 ha (0.68%) in 2000 to 19283.26 ha (4.13%) in 2021. Forest area management has shown a positive trend by significantly increasing in primary dryland forest areas, but there has also been a significant increase in mixed dryland agriculture areas. It is important to find solutions to prevent the spread of deforestation and maintain the sustainability and services of forest ecosystems.


Introduction
Land use change is a process by which human activities transform the natural landscape for economic activities.Land use changes are often nonlinear and might trigger feedback to the system, stress living conditions, and threaten people with vulnerability.Land-use change models play an important role in exploring possible future developments in the land-use system.With a model, the functioning of the system can be explored through "what-if" scenarios and the visualization of alternative land-use configurations that may be the result of policy decisions or developments in society [1] [2].Different types of land cover can be managed or used very differently.Land use/land cover change (LULCC) is recognized as a key component of environmental change at global, regional, and local scales.Changes in land use and land cover have implications for global warming, loss of biodiversity, land degradation, 1297 (2024) 012085 IOP Publishing doi:10.1088/1755-1315/1297/1/012085 2 watersheds, hydrology, and even human well-being [3] [4].However, the processes and factors associated with LULCC are very complex, resulting from interactions between humans and various environmental, socio-economic, policy, and institutional factors, each of which also contributes as driving factors [5][6] [4].
Deforestation in tropical regions is generally characterized as the conversion of forest land to other uses, especially agriculture.Changes in land use and land cover have a major impact on soil properties and land degradation which results in the decline of land in supporting plant growth and production [7][8] [9].In 2018, the forest cover figure in Aceh Province was reduced by 15,071 ha.The high rate of deforestation has severe impacts on the environment; Many natural disasters have occurred in Aceh, such as floods and droughts.One area in Aceh that is under quite serious pressure on land/forest resources is the Gayo Highlands (GH), consequently leading to a reduction in the quantity and quality of services they provide.Added to this is the pressure from climate change on coffee cultivation.GH is the main producer of Indonesian Arabica coffee.Coffee production in GH, which is cultivated at a lower altitude of 900-1000 m asl, experiences a very significant decrease in the quantity and quality compared to higher altitudes.This condition encourages farmers to look for new land that is more suitable in higher areas, which unfortunately are protected forests [10][11].Ramli et al. [12] reported that the deforestation that occurred in the Krueng Peusangan Watershed (KPW), where the GH-protected forest is one of the water catchments, was one of many watersheds in the country that was experiencing deforestation.It was found that between 1999-2009 and 2009-2019, there had been a consistent decrease in forest cover area and an increase in built-up area.Local climate change was also occurring in this KPW [13] [14].
Information regarding land use and land cover changes in Bener Meriah and Aceh Tengah Districts is very important, to: 1) provide information about land cover changes; 2) explain the land use dynamics of these changes; 3) explain the projected dynamics of the land use and land cover in the future; and 4) identify critical areas that are vulnerable to environmental change, which will be beneficial for the sustainability of coffee production and the preservation of forest areas.The objective of this research is to describe land use and land cover changes in Bener Meriah and Aceh Tengah Districts during 2000, 2006, 2014, and 2021.

Materials and methods
The study was carried out in areas within the protected forest in the GH which includes Bener Meriah and Aceh Tengah Districts.The material used in this study is Landsat satellite image data.Other supporting data is in the form of base maps and thematic maps regarding the study area.The base map consists of the Indonesian Land Map and Administrative Map.The thematic maps consist of a Regional Function Direction Map, Land Cover Map, Soil Type Map, and Watershed Map.
The land use and land cover systems in Bener Meriah and Aceh Tengah Districts were assessed for 2000, 2006, 2014, and 2021 using remote sensing data sources using satellite image data.The satellite image data used are Landsat 5 (TM) satellite images recorded in 2000 and 2006, as well as Landsat 8 (OLI) satellite images recorded in 2014 and 2020/2021 on path/row data, namely 130/57.The presentation of land cover classification data is presented by carrying out an image interpretation process, image interpretation is carried out to obtain a classification of land cover classes at the study location.The method for classifying land cover is carried out using a supervised method [15] [16][17], several stages of the classification process include pre-processing, interpretation of visual data, supervised classification, and accuracy test.
The analysis in this study is an analysis of land change by identifying patterns of land use and land cover change for each land use and land cover class [18][19] at the study location based on a period, namely between 2000, 2006, 2014, and 2021.The analysis was conducted by calculating the area of land cover change that has been interpreted based on the year class and determined by utilizing the Mic.Excel software extension in the form of a pivot table which is then presented and tabulated.In 2006, LULC in forest areas were still dominated by forest, namely primary dryland forest, secondary dryland forest, and plantation forest 166915.86ha (35.77%), 201995.22ha (43.29%) and 43800.16ha (9.39%), respectively.However, there were a decrease in the area of primary dryland forest cover and an increase in the area of secondary dryland forest cover.Other land cover were dominated by shrubs 24,875.33ha (5.33%) and savanna 22,670.96ha (4.86%).
In 2021, LULC in protected forest areas were still dominated by forests, namely primary dryland forest, secondary dryland forest, and plantation forest 250,348.45ha (53.65%), 103,153.16ha (22.11 %) and 45,601.12ha (9.77%), respectively.Primary dryland forest and plantation forest covers increased very significantly, which was marked by a decrease in the area covered by secondary dryland forest and shrubs.Other land covers were dominated by shrubs 31,472.96ha (6.74%), savanna 12,904.48ha (2.77%), and mixed dryland agriculture 19,283.26ha (4.13%).Apart from being marked by an increase in the area of primary dryland forest cover, this period was also marked by a very significant increase in the area of mixed dryland agricultural cover.
The comparative appearance of land use and land cover in 2014 and 2021 in the forest area is shown in figure 2. In Bener Meriah and Aceh Tengah Districts, LULC are proportionally very good, with Forest covers are more than 55% in Bener Meriah District and more than 69% in Aceh Tengah District.However, stakeholders need to pay attention that a good proportion forest cover does not necessarily indicate good forest cover quality.
Ramli et al. [13] reported similar results in the catchment area of Krueng Peusangan Watershed (KPW), the location of the protected forest of Bener Meriah and Aceh Tengah Districts, that forest experienced a significant decrease from 1999 to 2019, with a total loss of 21.76%.Deforestation in KPW was mainly due to the increase and expansion of agricultural activities, especially plantations and cultivation.Therefore, a balance was needed between environmental protection, mitigation, economic development, and social welfare [12] [20].
Forests play a significant role in increasing soil fertility, regulating water availability, and absorbing carbon, so the existence of forests is closely related to the success of agricultural businesses in a broad sense and the welfare of humanity.Two factors cause forest degradation, the first is an indirect cause and the second is a direct cause [21][22] [23].Indirect causal factors are the dominant causes of environmental damage, while direct causes are limited to the behavior of residents who are forced to exploit forests excessively due to necessity.Indirect causes include 1) population growth, 2) government policies that harm the environment, 3) industrialization of wood, housing, and paper industries, 4) failed reforestation and reclamation, 5) increase in poor people in rural areas, 6) weak law enforcement in the forestry and environmental sectors, 7) low level of public awareness of the importance of forest conservation.

Trends in Land Use and Land Cover Changes
The trend in the LULCC in this study is only focused on the 2014-2021 period, considering that during this period there were significant changes in primary dryland forest cover, plantation, dryland agriculture, and mixed dryland agriculture covers.Meanwhile, for the other LULC, analysis was carried out only for LULC that has a significant change, while those that were relatively constant were not analyzed.Trends in LULCC in forest areas in Bener Meriah and Aceh Tengah Districts for the 2014-2021 period can be seen in table 2.
Table 2 shows a very significant increase in primary dryland forest cover in the 2014-2021 period of 76,541.13ha.This addition comes from improving the quality of secondary dryland forest cover of 94,488.29 ha and shrubs of 1,008.00ha.This shows that there has been an increase in the quality of forest area management from encroachment practices.However, in the same period, there was also a decline in the quality of land cover from primary dryland forest to secondary dryland forest 17,180.55ha, 209.98 ha savanna forest, 1,293.04ha scrub, 181.86 ha open land, 29 ha savanna, 69 ha, and mixed agricultural dryland 60.04 ha.
The area of secondary dryland forest decreased very significantly to 103,151.16 ha, apart from changing to primary dryland forest of 94488,29 ha, plantation forest of 333,78 ha, and shrub of 12.553,29 ha, but there was also a significant change in land cover to plantations 70.14 ha, dryland agriculture 190, 57 ha, and mixed dryland agriculture 1,412.65 ha.
The area of plantation forest land cover decreased very significantly to shrubs 6778.62 ha, plantations 58.64 ha, dryland agriculture 18.67 ha, mixed dryland agriculture 3662.09ha, and rice fields 1764 ha.The 2014-2021 period was marked by a very significant change in land cover from shrub cover to mixed dryland agricultural land cover of 9,347.26ha, plantations of 478.63 ha, and dryland agriculture of 554.25 ha.
The conditions above show that improving forest protection governance in Bener Meriah and Aceh Tengah Districts needs more attention from stakeholders, especially from the Environment and Forestry Service, Aceh.Positive things have been produced by a very significant increase in primary dryland forest land cover, but on the other hand, guard forest management still leaves homework that must be handled more carefully, considering that in this period there has been an increase in land cover for activities.plantations 690.09 ha, dryland agriculture 862.12 ha, and mixed dryland agriculture 19,283.26ha from previously only 8.81 ha, 2493 ha, and 3175.44 ha, respectively.

Conclusions
Land use and land cover in Bener Meriah and Aceh Tengah Districts are proportionally very good, with forest covers are more than 55% in Bener Meriah District and more than 69% in Aceh Tengah District.However, stakeholders need to pay attention that a good proportion the forest covers does not necessarily indicate a good quality of the forest covers.
Forest area management in Bener Meriah and Aceh Tengah Districts during the period 2000-2021 has shown a positive trend by a significant increase in primary dryland forest areas, but there has also been a significant increase in mixed dryland agriculture areas.
It is important to find solutions regarding the existence of agricultural land in the forest areas, to prevent the spread of deforestation rates, and maintain the sustainability and services of forest ecosystems in the future.

Figure 1 .
Figure 1.Land use and land cover in protected forest areas in 2000 and 2006

Figure 2 .
Figure 2. Land use and land cover in protected forest areas in 2014 and 2021

Results and discussion 3
Publishing doi:10.1088/1755-1315/1297/1/012085.1.Land Use Land Cover The focus of the study is land use and land cover in the protected forest area within the administrative boundaries of Bener Meriah and Aceh Tengah Districts.Types of land use and land cover identified in forest areas in the administration of Bener Meriah and Aceh Tengah districts, i.e. primary dryland forest, secondary dryland forest, plantation forest, shrubs, plantation, settlement, open land, savanna, body of water, dryland agriculture, mixed dryland agriculture and rice field.After the classification of the identified land use and land cover classes, spatial data processing was carried out to obtain trend data on changes in land use and land cover.Detailed land use and cover data in Bener Meriah and Aceh Tengah districts for 2000, 2006, 2014, and 2021 are presented in table 1.

Table 2 .
Trend of land use and land cover change in forest areas in Central Aceh and Bener Meriah Districts for the 2014-2021 period T= Open land, S=Savana, A= Body of water, Pt= Dryland agriculture,