Analysis of built-up land development in the center of Boyolali District, Indonesia in 2009 and 2019

Built-up land development will continue to increase over time. Population growth and regional spatial plans are examples of several factors that influence the process of implementing built-up land development in an area. Boyolali Sub-district became an area with rapid development of built-up land that occurred between 2009 and 2019. Therefore, this study was conducted to determine the area of land that experienced development and to determine the distribution of the development of undeveloped land into built-up land. This study used satellite imagery in 2009 and 2019 of Boyolali. Those images are interpreted and digitized, resulting in two maps of built-up land of Boyolali Sub-district in 2009 and 2019. The change of undeveloped land into built-up land is not only centered in one place but spread across all areas of the Boyolali Sub-district. The results of this study show that the area of built-up land in Boyolali District increased from 2009 to 2019. The change of undeveloped land into built-up land in Boyolali District was 62.59 ha (625,900 m2) within 10 years.


Introduction
Community activities will not be separated from land as a place to live.The need for land to meet the needs of the population continues to grow but the availability of land to fulfil it is limited.Hauser [1] argues that 46% of urban population growth is due to population movement and regrouping.And 54% is due to natural growth.High population certainly affects the area of built-up land used.The population of each region continues to change.The increasing population can be caused by increasing birth rates and population movements that can result in changes in land use in an area.According to Malingreau and Christiani [2], land use is human intervention either permanently or periodically on land with the aim of fulfilling needs, both material, spiritual, and a combination of both land use is an important element in regional planning.
Classification of land cover/use is an attempt to classify various types of land cover/use into a similarity according to a certain system [3].Land use in each place is not the same, in rural areas land is used for social activities, and agriculture/plantations for community economic activities.Land in urban areas is more diverse in its use, for example for public facilities such as educational facilities, health facilities, and economic activities.The undeveloped land of an area includes green open space, agriculture, plantations, water areas, production, and mining of natural resources.In the district/city, the handling of green open space facilities for the realization of the city environment will be further regulated by the local regulation itself, which is an environmental facility program including the development of green lanes, parks, and river/channel conservation programs.Urban areas in Indonesia tend to experience typical problems, namely the high rate of population growth, especially due to urbanization, which causes the management of urban space to become increasingly difficult.Development in an area needs to be assessed in advance so that there is no damage to the ecosystem in the area and so that the budget used for development does not exceed the plans of the local government.Some studies about land development have been carried out.According to Bachtiar [4] in his study entitled Analysis of Land Use Change in Karanganyar District in 1998 and 2003, the study was conducted to determine the changes that occurred in the Karanganyar Subdistrict area in that year and to find out what factors influenced land use change in the study area.The level of population growth, population density per area, and the availability of public facilities to support community activities are factors that cause land change in the study area in that year.The development of residential areas is one of factors that influence land use change Rakuasa and Pakniany [5].Residential area development will increase along with population expansion and land demand.In Lafia, Nigeria land development from 1999-2019 caused suburban expansion and change the typical boundaries [6].
Boyolali sub-district had a population of 59,237 in 2009 which increased to 72,134 in 2019 [7,8].The development carried out must be in accordance with the city's spatial plan and remain environmentally sound so that the area can take advantage of its potential and not lose its characteristics that are not owned by other areas, so The government must have a development plan and in its implementation it needs to be supervised so that it is in accordance with the plan that has been set.The need for housing increases as a result of population growth in an area.The rapid development of the population has resulted in an increase in facilities to support people's lives such as roads, educational facilities, shopping centers, health facilities, and others.The area of land used for residential settlements is getting wider, also called the area of built-up land is increasing, so the availability of green open land is getting narrower.Green open land is not only used for community needs but also to maintain the ecosystem in an area.Green land in an area can function to preserve flora and fauna, green land with large trees can be useful to prevent soil erosion, become a water catchment area that can be used to meet community needs, and can also prevent flooding.Areas that do not have land for infiltration will be prone to erosion and prone to flooding.
Geographically Boyolali sub-district is located at 110⁰ 32' 56" east longitude to 110⁰ 38' 2" east longitude and 7⁰ 29' 11" south latitude 7⁰ 32' 56" south latitude.The northern part is bordered by Semarang Regency and Ampel District, Cepogo District to the west, to the south is bordered by Musuk District and Mojosongo District, and the east is bordered by Mojosongo District.Boyolali sub-district is located at an altitude of 400-700m above sea level and is classified as a medium plain.Boyolali Subdistrict is located in the center of Boyolali City and is one of the areas that the government pays the most attention to in its development programs.The addition of public facilities and improvements to existing public facilities such as road improvements, toll road construction, construction of city parks, construction of gas stations in Boyolali city center, and other facilities such as large public parking lots in Boyolali city center.Population growth and increasing urbanization flows that occur in the Boyolali Sub-district, road construction, and improvements to facilitate community accessibility to carry out socio-economic activities are examples of factors that change land from green land to built-up land in the study area.
The construction of the Trans Java toll road to facilitate community mobility between cities and across the northern Boyolali sub-district is also an example of the change of green land to built-up land.The mobility that occurs is not only people but also goods mobility.Mobility is one of the social and economic activities of the community.This movement/mobility can be utilized to encourage development growth, economic development, and utilized in other sectors.Supporting facilities for the socio-economic activities of the community available in Boyolali Sub-district include health facilities such as hospitals, markets, city parks, educational facilities, worship facilities, and accessibility that is quite adequate for this study area.This study utilizes imagery that can be obtained from Google Earth.The images used in this study are 2009 images of Boyolali Sub-district and 2019 images of Boyolali Sub-district.Analysis is a thinking activity to decompose a whole into components so as to recognize the signs of the components in relation to each other and their respective functions in an integrated whole (Komaruddin, 2002 in Zakky [9]).This study analyses maps that have been interpreted and digitized using the Arc.GIS 10.3 map processing application on the 2009 image of Boyolali Sub-district and the 2019 image of Boyolali Subdistrict.A similar study in Sadranan Beach, Gunung Kidul also used digitation and interpretation methods from UAV imageries, then resulted 8 land use classifications [10].The satellite image also can be used to monitor and study the sea surface temperature (SST) and the distribution of chlorophyll-a concentration since it has a thermal band and a fairly high temporal resolution [11].

Figure 1. Boyolali sub-district as the study area
Boyolali sub-district is located at an altitude of 400-700 mean sea level and is included in the classification of medium plains and this study area is located in the center of Boyolali City.Boyolali sub-district is nicknamed "The City of Milk" because of the abundant production of cow's milk in this area which has become one of the economic commodities.The population in Boyolali in 2009 was 59,237 people which increased to 72,134 people in 2019.

Tools and Materials
Software ArcGIS 10.3 was used in this research for geographic data processing and geospatial analysis.Data processing materials included satellite images of Boyolali Sub-district in 2009 and 2009 that were obtained from Google Earth.Besides that, this research also used statistical data of Boyolali in 2009 and 2019 from Badan Pusat Statistik.

Stages of data processing and analysis
The method used in this research was interpreting and digitizing the 2009 image of Boyolali District and the 2019 image of Boyolali District using the Arc.GIS 10.3.These processes generated the 2009 land use image and the 2019 land use image.Land use images are overlaid, and then used to calculate the built-up area development in the study area.

Research flow chart
This research was carried out through several stages starting from raw data to becoming a map of builtup land in Boyolali in 2019.Figure 2

Results
The analysis process is carried out after interpreting and digitizing the image.The results of the analysis in this study can be seen in Figure 2, Figure 3, and Table 1.The green color represents built-up land, yellow represents undeveloped land, blue represents built-up land that changed into undeveloped land, and red color represents undeveloped land that changed into built-up land.The area of each land development can be seen in Table 1.The development of undeveloped land into built-up land in Boyolali District from Table 1 is 62.59 ha / 625,900 m² in a period of 10 years.Undeveloped land in the area is quite extensive at 1441.96 ha.The change of undeveloped/empty land to built-up land is not only centered in one place.Based on the map, the development of built-up land spreads almost in all areas of Boyolali Sub-district.The construction of a toll road that crosses the northern part of Boyolali Sub-district, the development and improvement of accessibility, and the construction of housing as a place to live for both people who live permanently and people who only live temporarily in several areas in Boyolali Sub-district are examples of the development of built-up land that occurs in Boyolali Sub-district.

Discussion
Region is defined as a geographical unit with certain regional boundaries where the components within it have linkages and functional relationships between one region and another [12].In general, development in an area is certain.The development of built-up land is an example of development carried out by the government of an area that is useful for encouraging the development/growth of an area both in economic conditions, development of public facilities, social conditions, and the development of human resources in the region [13].
Boyolali Sub-district has experienced changes in land use in several areas and undeveloped land into built-up land has increased significantly.Land development occurs in several villages in Boyolali Subdistrict such as the construction of toll roads that pass through Penggung Village, Kiringan Village, and Karanggeneng Village.The development of built-up land is not only changing into toll roads but also the increase in settlements needed by the community, the increase in community public facilities such as educational facilities such as schools and universities [13], the construction of health facilities such as hospitals and health centers, and community economic facilities such as markets and malls/supermarkets.The development of parks and cities can also be used by the government and the community as green land that can be used as water catchment.
The development of an area certainly needs to be studied in advance so that the development is in accordance with the formulated regional spatial plan.The development also requires a land suitability study to avoid environmental damage [14].Boyolali sub-district is located at an altitude of 400-700m above sea level and is classified as medium land.Built-up land is located in a lower area than the surrounding area [15].The area of built-up land development obtained in the study in the Boyolali Subdistrict area between 2009 and 2019 has been presented in Figure 3 with the development of undeveloped land into built-up land in Boyolali Sub-district is 62.59 ha / 625,900 m² in a period of 10 years.The development of undeveloped land into built-up land is quite extensive, there is a significant development compared to previous years.Built-up land is located in a lower area than the surrounding area [15].
The study conducted by Bachtiar [4] has similarities with this study by examining land which is a place where humans carry out their activities both social and economic activities.The two studies certainly have differences, in the study conducted by Bachtiar [4] obtained the results of knowing land use change, and factors that encourage land use change in Karanganyar Subdistrict in 1998 and 2003, while the study conducted in Boyolali Subdistrict in 2009 and 2019 obtained the results of knowing the area of development of undeveloped land into built-up land, and knowing the distribution in which there was a change of undeveloped land into built-up land.

Conclusions
The results of the analysis of 2009 and 2019 the images of Boyolali Subdistrict can be seen in the area of built-up land in the Boyolali Subdistrict area in 2019 which has been overlaid and presented in Figure 3.The development of undeveloped land into built-up land in Boyolali Subdistrict is 62.59 ha / 625,900 m² in a period of 10 years.The development of an area certainly needs to be studied in advance so that the development is in accordance with the regional spatial plan that has been formulated by the government.Changes from undeveloped land to built-up land are not only concentrated in one place.It can be seen from the map that the development of built-up land is spread throughout almost the entire area of Boyolali District.
describes the flow chart of this research.

Figure 3 .Figure 4 . 6 Figure 3
Figure 3. Map of Land Use of Boyolali Sub-district in 2009 and 2019

Table 1 .
Land Development in Boyolali Sub-district from 2009 to 2019