Optimal Land And Water Allocation Model For The Maximization of Net Agricultural Return In Drought Prone Regions

In this study, the land and water resources allocation model was developed to determine optimal cropping patterns and water resources allocations at different rainfall probability exceedance levels (PEs) to ensure maximum agricultural return in the Hormat-Golina valley irrigation command area, Ethiopia. To account the uncertainty of rainfall variability, the monthly dependable rainfall was estimated at three levels of reliability (20, 50 and 80% PEs) which are representing wet, normal and dry seasons based on regional experience. The irrigation water demand which was used as an input to the optimization model was estimated at each level of reliability by using CROPWAT model. The net annual returns of optimal cropping patterns were estimated as 181, 179 and 175 million Ethiopia Birr at 20 %, 50 % and 80 % PEs, respectively. The result of the optimal cropping pattern indicates that, the net annual return of the command area was increased to 45.75%, 45.84% and 47.01% than the Government targeted at 20%, 50% and 80% PEs, respectively. The findings reveal that the optimal land and water resources allocation model is very useful to the planners and decision makers to maximize the agricultural return particularly in areas where land and water resources are limited.

PENGOPTIMALAN LUASAN LAHAN PERTANIAN TERHADAP KETERSEDIAN AIR PADA DAERAH IRIGASI TAMPA KABUPATEN BARITO TIMUR

Daerah Irigasi Tampa yang terletak di Kecamatan Paku, Kabupaten Barito Timur, Provinsi Kalimantan dengan luas baku sawah pada 2000 Ha, memiliki layanan jaringan irigasi sebesar 1.278 ha, Namun pada hanya terdapat 500 Ha yang dapat di manfaatkan untuk pertanian. Penelitian ini bertujuan untuk menganalisis ketersediaan serta kebutuhan air untuk pola tanam yang optimal. Penelitian ini memberikan solusi pola tanam yang optimal terhadap luasan lahan pertanian menggunakan sorfware bantu (weap, cropwat dan pomqm). Penelitian ini menggunakan beberapa perhitungan antara lain perhitungan curah hujan efektif, evapotranspirasi serta debit andalan. Selanjutnya dilakukan perhitungan ketersediaan air eksisting pada Daerah irigasi Tampa sesuai pola tanam yang ada. Tahapan selanjutnya dilakukan perhitungan kebutuhan air untuk pola tanam optimal. Hasil analisis ketersedian air dan kebutuhan air memberikan nilai debit maksimum 0,226 m3/dtk dan untuk debit minimum sebesar 0,154 m3/dtk dan kebutuhan air maksimum sebesar 9,684 mm/hr. Pengoptimalan dilakukan dengan 2 alternatif pola tata tanam dan menggunkan jenis tanaman padi unggul yakni alternatif pertama padi-padi-palawija dan alternatif ke dua padi-palawija-padi. Hasil perhitungan alternatif pertama adalah kebutuhan air maksimum sebesar 0,117 m3dtk dan kebutuhan minimum sebesar 0,003 m3/dtk. Untuk alternatif ke dua didapat kebutuhan air maksimum sebesar 0,146 m3/dtk dan kebutuhan minimum adalah sebesar 0,025 m3/dtk. Hasil pengoptimalan alternatif kedua didapat tanaman Padi 109 Hektar dan 111 hektar. Untuk Hasil Optimasi alternatif ke dua didapat 378,52 hektar padi dan 250,9 hektar tanaman palawija. Berdasarkan analisis diatas, alternatif pola tata tanam ke dua lebih optimal dalam memberikan produktifitas hasil tanaman dengan asumsi untuk padi unggul adalah 10 ton/ha dan palawija 2,3 ton/ ha maka didapat sebesar 3785,2 ton/ tahun untuk tanaman padi unggul dan 577,1 ton/ tahun untuk tanaman palawija. Kata kunci: irigasi tampa, kebutuhan air, ketersediaan air, pengoptimalan. The Tampa Irrigation Area, which is located in Paku District, East Barito Regency, Kalimantan Province, with an area of 2000 Ha of raw rice fields, has an irrigation network service of 1,278 ha, however only 500 Ha can be utilized for agriculture. This study aims to analyze the availability and demand for water for optimal cropping patterns. This research provides optimal cropping pattern solutions for agricultural land area using auxiliary software (weap, cropwat and pomqm). This study uses several calculations including the calculation of effective rainfall, evapotranspiration and mainstay discharge. Furthermore, the calculation of the availability of existing water in the Tampa irrigation area is carried out according to the existing cropping pattern. The next step is to calculate the water requirement for optimal cropping patterns. The results of the analysis of water availability and water demand give a maximum discharge value of 0.226 m3/s and for a minimum discharge of 0.154 m3/s and a maximum water requirement of 9.684 mm/day. Optimization is done with 2 alternative cropping patterns and using superior types of rice plants, namely the first alternative is rice-rice-palawija and the second alternative is rice-palawija-rice. The result of the first alternative calculation is that the maximum water requirement is 0.117m3 s and the minimum requirement is 0.003 m3/s. For the second alternative, the maximum water requirement is 0.146 m3/s and the minimum requirement is 0.025 m3/s. The results of the second alternative optimization obtained rice plants of 109 hectares and 111 hectares. For the second alternative optimization results obtained 378.52 hectares of rice and 250.9 hectares of secondary crops. Based on the above analysis, the second alternative cropping pattern is more optimal in providing crop productivity with the assumption that for superior rice is 10 tons/ha and palawija 2.3 tons/ha, it is obtained 3785.2 tons/year for superior rice plants and 577 ,1 ton/year for secondary crops. Keywords: optimization, tampa irrigation, water availability, water demand.

Hybrid optimization model for conjunctive use of surface and groundwater resources in water deficit irrigation system

The Increasing demand for food production with limited available water resources poses a threat to agricultural activities. Conventional optimization algorithm increases the processing stage and it performed with in the space, which is allocated from user. Therefore, the proposed work is utilized to design with better performance results. The conjunctive allocation of water resources maximizes the net benefit of farmers. In this study, a novel hybrid optimization model developed is first of its kind to resolve the sharing of water resources conflict among different reaches based on a genetic algorithm (GA), bacterial foraging optimization (BFO) and ant colony optimization (ACO) to maximize the net benefit of the water deficit Sathanur reservoir command. The GA-based optimization model considered crop-related physical and economic parameters to derive optimal cropping patterns for three different conjunctive use policies and further allocation of surface and groundwater for different crops are enhanced with the BFO. The allocation of surface and groundwater for the head, middle and tail reaches obtained from BFO is considered as an input to the ACO as a guiding mechanism to attain an optimal cropping pattern. Comparing the average productivity values, Policy 3 (3.665 Rs/m3) has better values relating to Policy 1 (3.662 Rs/m3) and Policy 2 (3.440 Rs/m3). Thus, developed novel hybrid optimization model (GA-BFO-ACO) is very promising for enhancing farmer's net income and can be replicated in other irrigated regions to overcome chronic water problems. The productivity value of policy 3 was 6.54% greater than that of policy 2, whereas that of policy 1 was 6.45% greater. Overall, the comparison shows the better performance analysis of various optimization is done successfully.

Hybrid Optimization Model for Conjunctive Use of Surface and Groundwater Resources in Water Deficit Irrigation System

Increasing demand for food production with limited available water resources pose the threat to agricultural activities. The conjunctive allocation of water resources maximizes the net benefit of farmers efficiently. In this study, a novel hybrid optimization model was developed based on a genetic algorithm (GA), bacterial foraging optimization (BFO) and ant colony optimization (ACO) to maximize the net benefit of water deficit Sathanur reservoir command. The GA-based opti-mization model considered crop-related physical and economical parameters to derive optimal cropping patterns for three different conjunctive use policies and further allocation of surface and groundwater for different crops are enhanced with the BFO. The allocation of surface and groundwater for the head, middle and tail reach obtained from BFO is considered as input to ACO as a guiding mechanism to attain an optimal cropping pattern. Comparing the average produc-tivity values Policy 3 (3.665 Rs/m3) has better values relating to Policy 1 (3.662 Rs/m3) and Policy 2 (3.440 Rs/m3). Thus, the developed novel hybrid optimization model (GA-BFO-ACO) is very promising to enhance the farmer's net income as well as for the command area water conservation and can be replicated in other irrigated regions of the globe to overcome chronic land and water problems.

Economic analysis to optimize food plant patterns in Paloh Sub-district, Sambas District

The potential of land in The Paloh sub-district for the development of rice-mung beans is quite large. The rice and mung bean cropping patterns have been cultivated by farmers. The problems faced by farmers are the use of fertilizers that are not optimal, the use of superior seeds is still low. This study aims to (1) study the use of farm inputs, costs, and income, (2) analyze the optimal cropping patterns in food crop farming in The Paloh Sub-District. Sambas District. The analytical method used is farm analysis and optimization of cropping patterns using linear programming. The results showed that the rainy season rice cropping patterns and the dry season rice cropping patterns resulted in an income of IDR 87,071,580 per year. Based on the optimization results, it was found that the rainy season rice was 0.61 ha and dry season rice was 0.88 ha.