Cereals–soybean intercropping is not well studied, despite the importance of these crops in increasing agricultural profitability and ensuring nutritional and food security in Southeast Asia. We compared different intercropping practices (IPs) with monocropping practices (MPs) for their yield and economic performance by small-scale farms without mechanization. The treatments were IPs of rice–maize, rice–soybean, or maize–soybean compared with MPs of rice, maize, or soybean as sole crops, across three provinces in the rainfed areas of western Indonesia with a wet climate. Our results show that the yield advantages using the land equivalent ratio of the IPs were 44% for rice–maize, 54% for rice–soybean, and 63% for maize–soybean compared to MPs. Rice equivalent yield, maize equivalent yield, and the gross margin under IPs were significantly higher per cycle than under MPs; IPs provided a substantially lower cost of production and of paid workers. Compared to just rice, there were additional net return gains of USD 160 and USD 203 ha⁻¹ per cycle under rice–maize and rice–soybean intercropping. Maize–soybean intercropping resulted in an additional net return gain of USD 153 ha⁻¹ compared to just maize. These results suggest there is considerable potential for small farmers to increase their yields and profits by intercropping in rainfed areas with a wet climate.

The potency and challenges of sorghum development in tidal swamplands in Indonesia have yet to be well studied. Thus, our study is the first to evaluate the land suitability, economic performance, and strategies for developing sorghum in the tidal swamplands in Central Kalimantan. We use the land suitability evaluation method, a gross margin and profit analysis, a break-even analysis, and a competitive analysis as the methods for assessing the potency and utilization of sorghum in this study. As a tool for decision-making, SWOT was also used, followed by a quantitative strategic planning matrix (QSPM) analysis. The results show that 578,511 ha of arable land is suitable for sorghum development. Economically, sorghum farming can generate IDR 12,894,000 per ha with a revenue-cost ratio of 1.72; the break-even price would be IDR 2447 per kg, around 42% lower than the current market price. Sorghum is also more competitive than cassava (Q = 0.76), sweet potato (Q = 0.58), and soybeans (Q = 0.61) and less competitive than maize (Q = 1.33). Based on the QSPM analysis, five alternative strategies were obtained for developing sorghum in tidal swamplands: (1) optimization of productivity; (2) improvement in the quality of human resources for farmers; (3) facilitation of partnership cooperation; (4) application of site-specific technology; and (5) optimization of waste utilization. These strategies show that the expansion of sorghum planting has potential in the tidal swamplands and economic value for the community.

The development of shallot cultivation at back quartz sand during rainy or off season can be considered as new innovation. The objectives of this study is to obtain shallot varieties that are adaptive in terms of the growth, production, and quality parameters. The research was conducted during off season in Palangkaraya. The experimental design used in this research is randomized block design (RBD) 4x3 with 4 treatments of varieties (Maja Cipanas, Tajuk, Bauji and Bima Brebes), and 3 replication for each treatment. The results showed that soil bulk density increased with the deepening of the soil, however soil water content decreased. Based on growth parameter, Tajuk showed the best results and significantly different comparing to Bima Brebes, with plant height consecutively 46.88 cm and 39.52 cm, number of leaves 70.7 and 35.27 and number of shoot 13.43 and 6.60. For production parameter, the weight of varieties of Maja Cipanas, Bauji dan Bima Brebes is 10 grams more than Tajuk with weight is 6,97 grams only. The produstion of Tajuk is low and not significantly different from Bima Brebes, with production is respectively 15.28 ton/ha and 13.31 ton/ha, while the varieties of Bauji showed the highest dry production of 22.4 ton/ha although it is not significantly different with Maja Cipanas that can produce 18.49 ton/ha. For quality parameter, the varieties of Bima Brebes showed the optimum results in terms of parameter of hardness of tubers and total dissolved solids (TDS) with the value of 4.9 kg /cm² and 16,42 % respectively.

The need of landuse planning become apparent since the lands have the opportunity to be developed. Appropriate landuse planning based on spatial land resource data management is then required, in order to achieve sustainable landuse. The objective of this study was to design and allocate appropriate agricultural land regions for land use policy through extensification and intensification programs in order to support sustainable food crops development areas. The procedure of land resource evaluation consisting of land capability evaluation (LCE) and land suitability evaluation (LSE) was applied to determine land allocation of arable lands for rice farming development. The use of geographic information system (GIS) technology was also employed not only for spatial data management but it can also be applied to support decision making within establishing landuse planning. In the case of Pulang Pisau District, land allocation for extensification and intensification regions are mainly found in southern part and mostly located at watershed areas with each total area of 380,261 ha (36.81%) and 29,941 ha (2.90%), respectively. In order to support these potential areas, specific programs can then be formulated to increase the yield and productivity for these regions.

The main problem faced by sloping lands in the humid tropic includes land degradation influencing natural ecosystem damage broadly. Land conversion and improper land-use have been widely recognized as the main cause of environmental damage since the demands for agricultural lands become greater than land resource available. The objective of this study was to determine the concept of appropriate land-use planning through environmentally sound spatial management in order to prevent land and environmental degradation. The sub-district of Antang Kalang was chosen as study area representing sloping lands in humid tropic that have a susceptibility to erosion. Conservation approach by the use of USLE erosion risk prediction model and land evaluation through land suitability classification was used in this study. The geographic information system (GIS) and remote sensing (RS) technology were applied to generate spatial basic information and to assist in spatial analysis. Two crops, upland rice, and rubber, representing food crop and estate p have been selected based on the local resource that has been existed since a long time ago. The result of spatial analysis shown that the arable land for agricultural practices covers 9,039 hectares (23.19%) while for non-arable land, it is allocated for forest preservation with total areas 29,934 hectares (76.81%). Land-use planning and land resources management involving conservation aspect and land suitability evaluation should be taken into account for farming practice at sloping lands areas since the value of soil loss potential appears as an indicator of erosion risk. Permanent cultivation system and the intercropping farming system is the option of recommended agricultural practice at sloping lands in the humid tropic that have a susceptibility to erosion.

The appropriate concept of land use planning is required since the lands have the opportunity to be developed for agricultural purposes. Gunung Mas regency with total areas of 1,084,012 hectares is mainly covered by forest with various slope classes. The objective of study was to allocate the lands to be utilized based on its capabilities and suitability for food and plantation crops. Land evaluation approach was implemented to provide appropriate land use planning especially for food crop farming and plantation. Hierarchically, procedure of land capability evaluation (LCE) was used to classify lands based on their capability to produce common cultivated crops without deteriorating over a long period of time. Therefore, the proper land use for cultivation was further analysis using land suitability evaluation (LSE) procedure to determine fitness of a given type of land for a specific crop. The application of GIS and remote sensing technology were then used to generate additional spatial data as basic planning analysis. The results showed that agricultural system was located and implemented appropriately at arable lands. The use of LCE and LSE procedure can then be implemented to promote proper land use on sustained basis as important part of agroecological management.