Food Availability Analysis based on Land Suitability Evaluation on Paddy Production in Banyumas Regency, Indonesia

Land suitability evaluation for specific uses can be prepared based on land conditions, in this case for paddy plants, which are the basic staple food of the community. This study aims to determine the land suitability for paddy, determine land balance which is based on the area of paddy fields and built-up land to determine the potential of existing land reserves, and to determine paddy productivity. The research was conducted in Banyumas Regency in three districts, Kedungbanteng, Patikraja, and Purwojati as sampling area. The methods used in this study are land suitability analysis with the land unit approach method and land suitability based on SPKL version 2.0 weighted factor method, land resource balance analysis by calculating the reserve of land resources to determine the amount of paddy reserves, and food security analysis with qualitative descriptive method. The results showed that the land suitability class for paddy in Kedungbanteng District was dominated by class N with the highest value of Ntc/eh/lp of 25,57%, Patikraja District by class S2 with the highest value of S2c of 20,13%, and Purwojati District by class Neh of 51,51%. The only district that still has land reserves that can be used is Purwojati District of 635 ha. Food security in Kedungbanteng District has the highest land productivity, followed by Patikraja District with stagnant land productivity, and Purwojati with low land productivity.


Introduction
Banyumas Regency is one of the regencies in Central Java Province that has a large paddy harvest area but lacks paddy production.Based on data from the Central Java Provincial Statistics Agency, Banyumas Regency in 2022 had a paddy harvest area of 52,539 hectares with a paddy production that only 284,554 tons.The production of paddy in Banyumas Regency can be categorized as non-optimal production, this can be caused by various things.In general, the lack of optimal paddy productivity can be distinguished by biophysical environmental factors and farmer's capability factors.Biophysical environmental factors are related to land capability and land suitability for paddy.Soil characteristics, such as suboptimal soil physical properties and low level of nutrients, are some of the causes of non-optimal paddy production in Banyumas Regency.Nonoptimal paddy production can also be caused by the low efficiency of fertilization, the selection of poor-quality paddy seeds, and the presence of plant pests and weeds [3].
Meanwhile, Banyumas Regency has a land conversion rate to built-up areas of 2,228 ha in the period of 2011-2021 [5].Land conversion occurs in paddy fields, moorlands, gardens, forests, vacant land, and water bodies.Until 2021, the area of paddy fields converted into built-up areas is 142.1 ha while the other side it has paddy field area of 31,501 ha.The decrease in the size 1313 (2024) 012023 IOP Publishing doi:10.1088/1755-1315/1313/1/012023 2 of paddy fields in Banyumas Regency can be caused by several factors.The results of the analysis show that the increase in populations, number of industries, and Gross Regional Domestic Product (GRDP) have a positive influence on changes in agricultural land in Banyumas Regency [6].Kondisi tersebut akan berdampak terhadap ketersediaan pangan yang ada di Kabupaten Banyumas dimana di saat yang sama produksi padi masih tergolong rendah dari luas lahan yang ada.Kedungbanteng, Patikraja, and Purwojati District are case study locations based on the differences in landform, slope, elevation, and irrigation system for the paddy field.Kedungbanteng terletak di sisi utara Banyumas dimana ia terletak di kaki Gunung Slamet.Patikraja memiliki kombinasi bentuklahan dataran dan kaki perbukitan struktural.Purwojati memiliki kombinasi bentuklahan lereng perbukitan struktural.Perbedaan dari faktor -faktor tersebut dapat menjadi bahan pertimbangan ketersediaan pangan dari wilayah kajian terkait.

Study Area
This study is in Banyumas Regency with an area of 1.328 km 2 and consists of 27 districts.Astronomically, Banyumas Regency is located between 7°15'05" -7°37'1" South Latitude and between 108°39'17" -109°27'15" East Longitude.Kedungbanteng district is located at the north part of Banyumas Regency.Patikraja district is located at the central part of Banyumas Regency.Purwojati district is located at the south part of Banyumas Regency.

Data
This study uses primary data in the form of field surveying and secondary data from various sources.Field survey activities aim to observe soil characteristics quickly in the field.The following are secondary data sources used in this study.

Land Suitability
Land suitability is the suitability of a piece of land as a place for a particular activity or use.Land suitability consists of the suitability of environmental physical properties which include climate, soil, topography, hydrology, and drainage.In contrast to land capability, land suitability emphasizes the suitability of a plot of land for a particular type of use so that it requires various considerations in its management aspects [7].Land suitability is assessed based on current land conditions (actual land suitability) or after improvement or land improvement (potential land suitability) [8].The structure of land suitability classification according to its level includes orders, classes, subclasses, and units [9].The order indicates the type of suitability of the land.There are two orders, namely suitable (S) and not suitable (N).Order S means that the land for sustainable use of the land is expected to provide benefits without significant risk to land resources.Meanwhile, order N means that land has quality that does not support sustainable land management, so its use needs to be reconsidered.There are four classifications of land suitability, namely highly suitable (S1), moderately suitable (S2), marginally suitable (S3), and not suitable (N).The results of this land suitability analysis can be used as a basis for land use planning so that land can be used more optimally, sustainably, and sustainability [9].The productivity of paddy plants based on land suitability class is S1 (100-80%), S2 (80-60%), S3 (60-40%), and N (<40%) from the potential paddy productivity of 8 tons/ha [10].
Land suitability is the suitability of a piece of land as a place for a particular activity or use.Land suitability consists of the suitability of environmental physical properties which include climate, soil, topography, hydrology, and drainage.In contrast to land capability, land suitability emphasizes the suitability of a plot of land for a particular type of use so that it requires various considerations in its management aspects [7].Land suitability is assessed based on current land conditions (actual land suitability) or after improvement or land improvement (potential land suitability) [8] (Ritung et al., 2007).The structure of land suitability classification according to its level includes orders, classes, subclasses, and units (FAO, 1976).The order indicates the type of suitability of the land.There are two orders, namely suitable (S) and not suitable (N).Order S means that the land for sustainable use of the land is expected to provide benefits without significant risk to land resources.Meanwhile, order N means that land has quality that does not support sustainable land management, so its use needs to be reconsidered.There are four classifications of land suitability, namely highly 1313 (2024) 012023 IOP Publishing doi:10.1088/1755-1315/1313/1/0120234 suitable (S1), moderately suitable (S2), marginally suitable (S3), and not suitable (N).The results of this land suitability analysis can be used as a basis for land use planning so that land can be used more optimally, sustainably, and sustainably [8].The productivity of rice plants based on land suitability class is S1 (100-80%), S2 (80-60%), S3 (60-40%), and N (<40%) from the potential rice productivity of 8 tons/ha [9].
This research uses the land unit approach and land suitability for paddy as its method.The method we used for land suitability is based on the implementation guidelines for the land suitability assessment system (SPKL) version 2.0 from the Center for Research and Development of Agricultural Land Resources, Ministry of Agriculture, 2015.The data collection process uses primary and secondary data to validate land suitability parameters.Land suitability parameters that use primary data by rapid determination are soil drainage, soil texture, soil depth, pH, slope, flood occurrence, and presence of rocks.Meanwhile, the parameters of temperature, water availability, cation exchange capacity, and base saturation were validated using secondary data.Each parameter was then processed using the Weighted Factor Method and determined the limiting factors affecting land suitability for paddy.The data collection process used qualitative methods with descriptive analysis methods.

Land Resource Balance
Land resource balance is a calculation that describes land area and changes in land area over a period where measurements use hectares or square meters.One of the functions of this calculation is to determine the potential and reserves of a land use with a certain utilization.In this case, the land use is in the form of paddy fields as one of the staple food sources for the population in Indonesia.The potential of this land can be determined based on the results of the land suitability classification in the relevant area while its utilization is determined through secondary data on the existing paddy field area.If both are known, then the reserve of land resources that can still be utilized can be calculated.In addition, the productivity of paddy that can be produced according to the theory of land suitability can also be estimated.The reserve of land resources can be calculated by the formula.
-Utilization land comes from the area of existing paddy fields in the region.
The calculation assumes that all non-agricultural land can be utilized without considering built-up land and already considering non-paddy agricultural land.The non-agricultural area is then calculated with the potential paddy that can be produced based on the land suitability class of each region.An area certainly has a variety of land suitability classes so that it can be determined through the middle value as a standard for calculation.In general, the formula that will be used is:

Food Availability
Food availability is the condition of food availability from domestic production and food reserves.Food availability in Indonesia, especially in Java, is closely related to the adequacy of rice supply.Paddy as a rice-producing crop is a very important commodity for Indonesia as a producer of staple food.Efforts to increase rice production in Indonesia have been ongoing throughout history and have become a top priority in development, especially in the agricultural sector.The main strategies undertaken in efforts to increase rice production include intensification and extensification of paddy cultivation [12].
Intensification is carried out by applying varietal technology and cultivation techniques to increase land productivity both through increasing yields per unit area and increasing planting intensity each season [12].This is related to land suitability in supporting paddy farming.The condition of agricultural land is systematically exhausted and there is a diminishing water supply.Thus, in maintaining and increasing land productivity, the water scarcity factor is a limiting factor that needs to be addressed to support the sustainability of paddy field systems through irrigation systems [13].
Meanwhile, extensification is carried out by opening new paddy fields through the construction of irrigation networks, printing new paddy fields, expanding paddy cultivation, and opening swamp land [12].The significant rate of conversion of agricultural land to nonagricultural uses, especially paddy fields, has resulted in a decrease in paddy fields.This is due to an imbalance in the food land balance because the development of new food agricultural land is not balanced with the conversion of productive agricultural land into other functions such as settlements due to an increase in population [13].(Chaerani et al., 2010).Food availability analysis is identified through the condition of paddy productivity in an area.Paddy productivity of the three districts in Banyumas, namely Kedungbanteng, Patikraja, and Purwojati, was obtained through secondary data.The parameters used were paddy production (tons) and land area (ha) obtained from the Department of Agriculture and Food Security of Banyumas Regency.

Land Suitability for Paddy
Land suitability for paddy was carried out in Kedungbanteng, Patikraja, and Purwojati districts which have differences in landform, slope, and altitude to irrigation systems on paddy fields.The results of the land suitability assessment for rice fields are presented in Table 2, which consists of moderately suitable (S2), moderately suitable (S3), and unsuitable (N) areas.Each land suitability class has a limiting factor as a determining factor in land use planning.2, the class of land suitability or paddy plants that dominate in Kedungbanteng District is class N which is presented in red with a percentage of 75.22%.The limiting factors of this class consist of erosion hazard (eh), temperature (tc), land preparation (lp), and rooting media (rc).The next class of land suitability for paddy plants in this district is quite suitable (S2) which is presented in green with a percentage of 19,37%.As for the limiting factors in this class consist of rooting media (rc), erosion hazard (eh), and nutrient retention (nr).Lastly, the land suitability class for paddy is slightly suitable (S3) which is presented using yellow color with a percentage of 5,40%.Limiting factors in this class consist of erosion hazard (eh) and land preparation (lp).

Figure 3. Map of land suitability for paddy fields in Kedungbanteng District
Based on Table 3, the limiting factor in the form of erosion hazard (eh) is found in every area in the Kedungbanteng district.The Kedungbanteng area is prone to disasters where in 2018 -2019 there were 14 landslides, 3 fallen trees, 1 fire, and 1 extreme weather [14].As for the landslide disaster in Kedungbanteng Subdistrict, Banyumas Regency in 2019 resulted in dozens of damaged houses and dozens of lives lost.The Kedungbanteng Regency area is included in the Logawa Sub-watershed area whose geomorphology is divided into volcanic and structural formations that have different characteristics [15].Volcanic formations are composed of loose volcanic materials such as lava, while structural formations are composed of sedimentary rocks of Tertiary age.The nature of loose materials such as lahars and sedimentary rocks of Tertiary age makes landslides easy to occur.Patikraja district has a a different total area and percentage for each land suitability class (Table 4).The largest percentage of land suitability in Patikraja is 27,99% on land suitability subclass S3eh.Whereas the smallest percentage of land suitability id 1,98% on land suitability subclass S3rc.Both the largest and smallest percentage are located at land suitability class S3, the difference is the subclass or limiting factor.Therefore, it can be concluded that the limiting factor has a considerable influence on the classification of land suitability.4, it could be idenified that most of the limiting factor on Patikraja district are Rooting Condition (RC) and Erosion Hazard (EH).There are several ways to improve the limiting factor for erosion hazard.Erosion hazard can be improved by crop rotation [16].The best way to prevent soil erosion is crop rotation because it is a conventional and easy to implement process of changing crops to prevent excessive uptake of soil nutrients by a single crop.This enhancement of EH limiting factor can be applied in Patikraja District because of the relief of slight slope and categorized in the plain landform.
Rooting condition as one of the limiting factors on land suitability in Patikraja district is permanent and cannot be improved [17].Drainage, soil texture, and soil depth are the characteristics of land that are used in the rooting condition limiting factor.These are the three characteristics of land which are permanent as of their natural condition.Based on these twolimiting factors, land suitability subclass S3eh and Neh can be improved, while the land suitability subclass S3 rc cannot be improved.Based on figure 4, land suitability for paddy fields in Purwojati district shows moderately suitable (S2), marginally suitable (S3), and unsuitable (N).The result of the land suitability assessment indicated that 48,49% of Purwojati district is suitable for rainfed paddy fields.Of this, 1,58% of the area is moderately suitable, 46,91% is marginally suitable (Table 5).Unsuitable areas for rainfed paddy fields 51,51% and mostly spread in the suburbs of Purwojati District.The moderately suitable land (S2) means that the land has a limiting factor that will affect its productivity and requires additional input.The marginally suitable land (S3) means that the land has several limiting factors that severely affecting plant growth, requiring sustained agricultural treatments which often increase the expenditure which are difficult to justify, or otherwise will reduce productivity [18].The limiting factors of land suitability Purwojati District are erosion hazard (eh) and rooting media (rc).6 above, it is known that in the three case study areas, each area has a significant area in terms of paddy field, non-paddy area, and non-agricultural area.Land potential has an important meaning in land management and land use.Land is said to be a potential land if it has a high level of subtraction and has a carrying capacity for human needs so that it has high economic value.High land potential can produce high quality crops and produce more crops.Land use on land that has high potential certainly has a positive impact on the results of land use.The potential of land for agriculture, especially paddy fields, is very necessary in its management.This is because paddy production is also influenced by land potential.Land that has high potential automatically produces high paddy production.Based on the calculation of the balance of land resources in each district (Table 7), only Purwojati district still has land reserves that can still be utilized where approximately 635 ha can still be utilized as a food source in the region.Purwojati has a majority land suitability class of S3.In class S3, land can produce paddy around 40 -60% of the maximum yield of tons/ha that can be produced.According to theory, 1 ha can produce 8 tons/ha of paddy under the best conditions.If the average S3 class is assumed to be 50%, then the land can produce 4 tons/ha of paddy.With an area of 635 ha, the district is still capable of producing 2,540 tons of paddy to at least meet the basic needs of the population in the region.Based on the results of the land productivity graph in Kedungbanteng, Patikraja, and Purwojati Districts in 2018-2022, there are differences between the three districts.In general, Kedungbanteng District has the highest land productivity.Patikraja tends to have stagnant productivity, while Purwojati has the lowest land productivity.

Food Availability
The land productivity of Kedungbanteng District always exceeds that of Patikraja and Purwojati District, except in 2021.However, the land suitability for paddy in this district is only 24.78%.Based on this, the larger the area of land that is not suitable for paddy crops, is 75.22%.The unsuitability is due to geomorphological factors in the form of volcanic formations with frequent landslides.The high land productivity in Kedungbanteng district proves that there are more active paddy fields compared to paddy fields that are potentially suitable for land suitability.This can make Kedungbanteng District have the highest land productivity.
Patikraja district with productivity tends to stagnate due to the dominant land suitability suitable for paddy fields in the district, which is 74.31%.In addition, in terms of optimal land balance in land use as paddy fields with active land that exceeds potential land, so that productivity in the district is quite good.However, in 2022 it decreased quite significantly.Average land productivity in 2018-2021 reached 6.23 tons/ha, while in 2022 only 5.30 tons/ha  was below the average land productivity.The decline in land productivity is caused by climate change that affects the paddy planting cycle.According to the irrigation system, Patikraja district was initially irrigated by the Banjaran River, but due to land conversion in Purwokerto, the irrigation conditions have changed [19] .Meanwhile, land productivity in Purwojati District being the lowest can be caused by land suitability which shows that 48.49% of Purwojati District area is suitable for rain-fed paddy fields.Thus, more than half of the district area, or 51.51%, is not suitable for wet-paddy farming as a food reserve.The limiting factor of land suitability in the form of erosion hazard needs to be evaluated to be able to increase productivity through land suitability, one of which is with crop rotation.In addition, the low productivity in Purwojati District is also caused by the lack of maximum land utilization in the district.Based on previous results on land resource balance, Purwojati District still has land reserves that can be utilized around 635 ha as a source of food availability in the region.Purwojati District in the form of erosion.Food security in Patikraja District is high even though land suitability is low.This is because there are many active paddy fields compared to paddy fields that are potentially suitable for land suitabily.

Recommendation
In general, recommendations that can be considered are capacity building in terms of farmers, the importance of further education about the limited land conditions, planting methods that can be applied to maximize yields, and mitigation against climate change that can affect the lack of paddy productivity.

Figure 4 .
Figure 4. Map of land suitability for paddy fields in Patikraja District

Figure 5 .
Figure 5. Map of land suitability for paddy fields in Purwojati District

4 . Conclusion 1 .
Land suitability for paddy in the three case study areas has three classes, namely S2, S3, and N.Each class of land suitability has a limiting factor as a determinant in land use planning.Land suitability for paddy in Kedungbanteng District is dominated by class N with the highest value of Ntc/eh/lp at 25,57%, Patikraja District is dominated by class S2 with the highest value of S2rc at 20,13%, and Purwojati District is dominated by class Neh at 51,51%.Kedungbanteng and Purwojati District are not suitable for paddy, while Patikraja District is moderately suitable for paddy.2. Land balance based on the calculation of land resource balance in three districts, only Purwojati District has land reserves that can be utilized.The land reserve is 635 ha and capable to producing 2,540 tons of paddy.3. Food security in Kedungbanteng District has the highest land productivity, followed by Patikraja District with stagnant land productivity, and Purwojari with low land productivity.Kedungbanteng District has land suitability for paddy of 24%, Patikraja District has land suitability of 74%, while Purwojati District has land suitability of 48,49%.The limiting factors in Kedungbanteng District are landslides, Patikraja District in the form of climate change, and

Table 1 .
Source of secondary data used in research.

Table 2 .
Area of land suitability for paddy fields in each district

Table 3 .
Area of land suitability subclasses in Kedungabanteng District

Table 4 .
Area of land suitability subclasses in Patikraja District

Table 5 .
Area of land suitability subclasses in Purwojati District

Table 6 .
Comparison of Paddy Field Area and Non-Agricultural Land of Banyumas Regency in 2022

Table 7 .
Land Reserved of Banyumas Regency in 2022