Identification of land characteristics to increase red chili productivity in Mangunan, Bantul, Indonesia

Red chili the vegetable commodities with significant economic value. The supply of chili is often constrained, so it is necessary to increase the land. Land suitability evaluation is needed to determine the suitable of land in Mangunan, Bantul for cultivation of red chili. The objective of this study is to identify land characteristics for red chili to facilitate the expansion of cultivation areas. The study was done using a survey method The soil analysis is conducted in accordance with the methodology prescribed by the Indonesian Centre for Land Resources and Agriculture. The results showed that the actual land suitability at altitudes of 0-300 m asl is S3 with a limiting factor being P element. The height of 300-350 m asl is N with limiting factor slope of land. At altitudes of 350-400 and 400-450 m asl is S3 with limiting factors C- organic and P element. After evaluation and improvement efforts, the suitability of potential land at an altitude of 0-300, 350-400 and 400-450 m asl was S2 with improve the addition of organic matter or fertilization P. The altitude of 300-350 m asl was S3 with improve making bench terraces and parallel planting.


Introduction
One vegetable item that receives a lot of attention is red chili, which has a high economic value and has grown to be an essential element of Indonesian culture.[1,2].Every year, the need for chili grows due to the growing population and the emergence of industries that need the raw ingredients for chili.The significant demand for chilies as a culinary spice, in the food business, and for medicinal purposes has the capacity to yield substantial revenues.Red chili plants are plants that can be planted regardless of a particular season, because of its nature that does not know the season [3].However, the price fluctuations of red chilies are so large that they require a strategy in their cultivation.Based on data from [4], Red chili production had a decline from the previous period.The amount decreased from 1.5 million tons to 1.36 million tons compared to the previous year.However, the demand for chili is always increasing, On the other hand, demand for red chilies is increasing which has caused the government to import them [5,6].
Bantul Regency is one of the red chili producers in DIY province.In 2018 the red chili harvest area was 381 hectares with a harvest of 15,957 quintals, in 2019 the harvest area increased to 535 hectares with yields increasing to 16,540 quintals.In 2020 the harvest area increased from the previous year to 587 hectares and yields increased to 64,603 quintals [7].The productivity of red chilies in Bantul Regency needs attention from the government and farmers, this is because red chili plants have high economic value and are the main horticultural crop used by the community.On the other hand, land conversion also always occurs.Most of the agriculture land was turned into houses and housing [8,9].Therefore, it is necessary to expand agricultural land to replace agricultural land that has been converted.
One of the areas that can be developed as a source of red chili cultivation is Mangunan Village.Mangunan Village is one of the areas in Bantul that is not used as land for chili cultivation.According to data [10], horticultural agricultural statistics of Dlingo District in 2018-2021, especially on red chili commodities, have fluctuating data on the area of harvest and production of large chili.In 2018, the harvest area of large chili horticultural crops was 3 hectares with a production of 157 quintals, then in 2019 and 2020 the harvest area decreased to 0 hectares with a production of 0 quintals, and in 2021 the harvest area of large chili plants increased from the previous year to an area of 1 hectare with production reaching 26 quintals.On the other hand, Mangunan village is one of the agro tourism destinations developed by the local government.The development of horticultural centers can be carried out, one of which is by cultivating red chili plants.This condition makes the Mangunan area not used as a center for horticultural crops including large chili, although it has the potential for the development of chili plants.Based on these conditions, land evaluation is needed to find out whether the Mangunan area can be used for large chili cultivation or not.Information about land characteristics will be an input in the context of developing red chili cultivation areas.
Land evaluation is a method used to assess the quality and suitability of land for future development purposes.Land appropriateness refers to the degree to which land is suitable for specific purposes.The condition being referred to is the current state of the land, both before and after it has undergone repairs.In order to determine the suitability of land for specific purposes, it is essential to categorize land suitability.Land suitability classification is the evaluation and categorization of land based on its appropriateness for specific purposes [11][12][13].Hence, it is necessary to assess the appropriateness of the site in order to get data on land suitability for cultivating chili plants.This evaluation was carried out in addition to supporting the supply of red chili needs, as well as one of the agrotourism destinations developed in Mangunan village.The purpose of this study is to identify land characteristics for large chili plants as one of the developments of red chili cultivation areas in the Special Region of Yogyakarta.

Studied area
The research was done in Mangunan.Mangunan Village is one of the areas located in Dlingo District, Bantul Regency and held from July 2022 to March 2023.The distance from Yogyakarta to Mangunan Village is about 28 kilometers.The area of Mangunan Village is 952.37 hectares consisting of 6 villages, including Cempluk, Sukorame, Lemah abang, Kanigoro, Kediwung, and Mangunan.The characteristics of the soil in Mangunan Village as a sampling are the types of Mediterranean and Latosol which have an altitude of 300 to 450 meters above sea level and have hilly contours.The annual air temperature in Mangunan Village in 2017-2021 is 22-30°C which is the optimum temperature for growth [10].The administrative map of Bantul Regency (a), position of Dlingo District on the map of Bantul Regency (b) and the location of the research (c) can be seen in Figure 1.

Data collection and analysis
The study employed a survey methodology and conducted descriptive and geographical analysis using Arc-GIS.Soil sample is conducted to assess the specific characteristics of the land in Mangunan Village, taking into account the elevation of the area.Determination of soil sample points can be done by mapping areas / areas based on height and area that can be determined from the DEMNAS map which is then converted into contour lines on topographic maps.
From the DEMNAS map, the area can be determined which then determines the sample point to be taken.Mangunan Village has 6 hamlets, namely Cempluk, Sukorame, Lemah abang, Kanigoro, Kediwung, and Mangunan, which are the research locations.Soil sampling locations carried out at each altitude, namely 0-300 m asl, 300-350 m asl, 350-400 m asl, and 400-450 m asl.Representative samples were taken at different altitudes.At altitudes 300-350 m asl, 350-400 m asl, and 400-450 m asl each is represented by 4 representative samples, while at altitude 0-300 m asl is represented by 10 representative samples.The representative sample was taken based on the area size (Figure 2).The suitability classification of land for red chili was evaluated using the matching method in data analysis.To determine land suitability classes, this research uses the law of the heaviest limiting factors [14].The analysis results are grouped into classes very suitable (S1), quite suitable (S2), marginal suitable (S3), and unsuitable (N) [11][12][13][14][15]. Determination of land suitability classes is displayed using spatial analysis using ArcGIS which is used to map land suitability classes [16].

Results and discussion
There is an urgent demand for available land for the cultivation of agricultural crops.Nevertheless, urbanization has resulted in the transformation of certain agricultural areas into developed land.Land identification is necessary in order to increase agricultural areas and ensure that plant culture adheres to the standards for optimal plant growth.Red chili is a highly profitable agricultural commodity that is favored by farmers.Nevertheless, the consistent decline in red chili production in Mangunan necessitates the identification of land suitability.The availability of land for crop cultivation, especially red pepper plants, will ensure the sustainability of farming.
Table 1 shows the results of the analysis and land suitability for each parameter.The results of the analysis showed that most of the parameters at all altitudes are appropriate for chili.However, research conducted using the matching method using the main weighting factors, the existence of suitable parameters for chili is ignored.
Land suitability in its natural condition, known as actual land suitability or present suitability, refers to the level of appropriateness without taking into account any improvement initiatives or management strategies to address existing limits or limiting factors in each map unit.These limiting factors are observed soil and climate characteristics that are associated with the growing conditions of the plants evaluated.
The investigation revealed the specific land suitability class in Mangunan Village across four different altitude locations.
Climate data indicates that Mangunan experiences significant precipitation, which is a challenge for chili farming.The rainfall in this location falls within the S3 category, indicating moderate appropriateness based on land suitability factors.Rain is needed for water supply, especially for rainfed land.Local climatic conditions will determine the success of crop cultivation [17].
Based on the matching results, the location is classified as part of the S3-na subclass, along with the S3wa, na,eh level, at an altitude ranging from 0 to 300 meters above sea level.At this height, the land adaptability is classed as somewhat suitable due to limiting factors such as water availability, nutrient availability (particularly P2O5), and land slope.Potential land suitability refers to the appropriateness of land that can be attained through land improvement endeavors.The potential land appropriateness is determined by the input provided, taking into account the amount of management to be implemented.This allows for the estimation of land productivity and production outcomes per unit area.The primary limiting issue in Mangunan Village, situated at an elevation of 0-300 meters above sea level, is the deficiency of phosphorus (P) minerals., the improvement effort is to provide P2O5 fertilizer as recommended and the addition of organic matter [18][19][20].Improvement efforts that can be made due to high rainfall include creating proper drainage channels so that water can be minimized around red chili plants.Another effort that can be made in cultivating red chili plants is by raising the beds and using mulch [21,22].The land suitability class within an altitude range of 0-300 meters above sea level, now classified as S3wa, na, eh, will potentially be reclassified as S2wa, na, eh.The primary limiting factors for this change are the availability of phosphate, rainfall, and land slope.
The availability of nutrients will affect plant growth.Nutrient supply is needed in both vegetative and generative phases of plants.Lack of nutrients will cause plants not to grow optimally and as a result the results obtained will also not be optimal [23].Fertilizer application will help plants get an adequate supply of nutrients.However, fertilizer application must be carried out in accordance with the provisions to maintain the sustainability of the land used.

Table 1. Characteristics of land suitability for red chili.
Situated at an elevation ranging from 300 to 350 meters above sea level, this area falls under the Neha sub-class with Neh-1unit levels.This indicates that the land suitability class is deemed unsuitable due to the limiting factor of the land's slope.The altitude ranging from 350 to 400 meters above sea level falls into the sub-class S3-wa, nr, na, eh.This sub-class is characterized by unit levels S3wa, nr-4, na-2, eh-1, indicating that the height is categorized as marginally suitable.The limiting variables for this classification are the availability of C-organic and P2O5.Furthermore, the altitude of 400-450 meters above sea level is included in the sub-class S3-wa, nr, na.eh with unit levels S3wa, nr-4, na-2, eh-1 which means that the height is classified as land marginal suitability with main limiting factors for the availability of C-organic and P2O5.In addition, situated at an elevation ranging from 300 to 350 meters above sea level, the actual land suitability class with unit levels Neh-1 with limiting land slope.Improvement efforts that can be made are by building terraces if land conditions allow [24,25].However, if the slope of the land is too high, it is not recommended to cultivate annual crops, including cultivating red chilies, planting parallel to the contours, and planting ground covers.So that the altitude of 300-350 meters above sea level will be a potential land suitability class S3eh-1.
Altitudes of 350-400 and 400-450 meters above sea level actual land suitability class at the unit level S3wa, nr-4, na-2, eh-1 with main limiting factors C-organic and nutrient deficiency P. efforts to improve it are by adding organic matter and applying P2O5 fertilizer.Synthetic fertilizer commonly used to meet the needs of element P in the soil is SP-36.For the availability of P elements to be even more optimal, meeting P needs must pay attention to the accuracy of dosage and time in accordance with plant needs.So that the altitudes of 350-400 and 400-450 meters above sea level will be potential land suitability classes S2wa, nr-4, na-2.eh-1.At all altitudes, factors that limit water availability, especially due to high rainfall, can be overcome by constructing drainage channels or by making raised beds.while the limiting factor is the slope of the land, making terraces can be done as long as the slope of the land still allows.However, on high slopes of land, it is best not to plant annual crops.
The results of the analysis carried out, the actual suitability of land for chili in Mangunan Village are presented in Figure 3.The figure depicting the prospective land suitability is displayed in Figure 4.

Conclusions
Mangunan Bantul, Special Region of Yogyakarta has land characteristics with soil texture, namely red clay, appropriate category drainage, effective depth of deep roots and not a flood-prone area.The soil exhibits a high cation exchange capacity (CEC), high base saturation (KB), acidic pH, medium to low organic carbon content (C-organic), medium total nitrogen content (N), low phosphorus content (P), and high potassium content (K) suitable for growing red chili.
The findings of the land suitability analysis conducted in Mangunan Village for chili cultivation indicate that at an elevation of 0-300 meters above sea level, the suitability level is classified as S3 (marginal suitability) due to the limiting factor of element P. The height of 300-350 m asl is N (not suitable) with limiting factors slope of land.At altitudes of 350-400 and 400-450 m asl is S3 (marginally suitable) with limiting factors C-organic and element P.After evaluation and improvement efforts, it was obtained that the suitability of potential land in Mangunan Village for chili at an altitude of 0-300 m asl was S2 (quite suitable) with efforts to enhance the incorporation of organic matter or the application of P fertilizers.The altitude of 300-350 m asl was S3 (marginally suitable) with efforts to improve making bench terraces and parallel planting.At altitudes of 350-400 and 400-450 m asl is S2 (quite suitable) with efforts to improve the addition of organic matter and P fertilization.
To ensure the sustainable production of red chili plants in Mangunan, it is necessary to provide organic materials, fertilize the plants, and practice parallel planting.Terracing can be implemented at an elevation of 300-350 meters above sea level (asl) in order to mitigate the risk of erosion and minimize environmental damage.

Figure 1 .
Figure 1.Map administration of Bantul District and Mangunan Village as a research location.

Figure 2 .
Figure 2. Map of the altitude of the representative sample.

Figure 3 .
Figure 3. Map of the actual land suitability for red chili in Mangunan Bantul, special Region of Yogyakarta.

Figure 4 .
Figure 4. Map of the potential land suitability for red chili in Mangunan Bantul, special Region of Yogyakarta.