Sebaran Spasial Konversi Lahan Sawah dan Penetapan Alternatif Lokasi Lahan Pangan di Kabupaten Toba

Abstract

Isu strategis sektor pertanian di Kabupaten Toba adalah konversi lahan sawah. Belum adanya Perda Lahan Pertanian Pangan Berkelanjutan (LP2B) menjadi ancaman bagi lahan sawah di Kabupaten Toba. Lokasi geografis wilayahnya yang strategis menjadi daya tarik investor dan masyarakat untuk membangun fasilitas pelayanan, sehingga mendorong perkembangan wilayah. Peran Kabupaten Toba sebagai penyuplai beras terbesar keenam di Sumatera Utara harus dipertahankan melalui penetapan lahan sawah prioritas. Tujuan penelitian ini: (1) menganalisis tingkat perkembangan wilayah Kabupaten Toba; (2) mengidentifikasi konversi lahan sawah serta sebaran spasial dan faktor penentunya; (3) menganalisis kesesuaian lahan untuk padi sawah; (4) menentukan lahan sawah prioritas dan strategi pengendalian konversi lahan sawah di Kabupaten Toba.

Bahan penelitian diperoleh dari instansi pemerintahan dan hasil wawancara dengan responden. Data sekunder terdiri dari peta RTRW Kabupaten Toba tahun 2017-2037, data potensi desa (Podes) Kabupaten Toba tahun 2020 dan 2021, peta penggunaan lahan sawah Kabupaten Toba tahun 2010 dan 2020, Satuan Peta Tanah (SPT) Kabupaten Toba, dan peta RBI Kabupaten Toba. Alat yang digunakan meliputi Arcgis 10.3, QGIS 3.6, GeoDa, SPSS statistics 20, kuesioner, dan kamera digital. Metode analisis yang digunakan meliputi Skalogram, Global and Local Moran Index, Regresi Logistik, dan AWOT yaitu gabungan Analytic Hierarcy Process (AHP) dan Strengths, Weaknesses, Opportunities, and Threats (SWOT).

Hasil penelitian menunjukkan bahwa pada tahun 2020 dan 2021 terdapat 4 kecamatan yang tergolong relatif berkembang, 4 kecamatan cukup berkembang, dan 8 kecamatan lainnya kurang berkembang. Pada tahun 2010-2020, lahan sawah terkonversi ke penggunaan lain seluas 3.529 ha yang mengelompok di Kecamatan Balige. Faktor penentu konversi lahan sawah meliputi jarak yang semakin dekat ke pusat pemerintahan, jarak yang semakin dekat ke pasar, dan pola ruang. Kesesuaian lahan untuk padi sawah di Kabupaten Toba terdiri atas 3 kelas, yaitu S2 seluas 7.787 ha dan menyebar di seluruh area serta S3 seluas 7.287 ha dan mengelompok di bagian Barat area Toba, khususnya di Kecamatan Laguboti dan tetangganya. Sedangkan kelas N seluas 1.579 mengelompok di bagian Timur area Toba. Lahan sawah prioritas di Kabupaten Toba terdiri atas 3 kelas, yaitu prioritas 1 seluas 10.305 ha, prioritas 2 seluas 1.784 ha, dan prioritas 3 seluas 4.632 ha. Strategi yang disarankan untuk pengendalikan konversi lahan sawah di Kabupaten Toba meliputi penerbitan Perda LP2B, pemberian subsidi input produksi kepada petani, dan memanfaatkan APBD pada sektor pertanian untuk pembangunan infrastruktur pertanian.

Paddy field conversion is an agricultural strategic issue of Toba Regency. Toba have not enacted regional regulations concerning sustainable agricultural land yet, which may threaten the existence of paddy fields. The strategic location of Toba could attract investors and societies to build public facilities that encourages regional development. The role of Toba as the sixth biggest rice supplier in North Sumatra should be maintained by prioritizing the paddy fields. The aims of this study were: (1) to analyze regional development of sub-districts of Toba Regency, (2) to identify paddy field conversion, their spatial pattern, and the driving factors of the conversion, (3) to analyze the suitability of cultivating paddy field, (4) to determine the priority of paddy field protection and to generate strategies for controlling paddy field conversion. This study used secondary data from government agencies and interviews respondents. The secondary data consisted of RTRW map of Toba for 2017-2037, village potential data of 2020 and 2021, a paddy field map, a soil map, and an Indonesian basemap (RBI). The study used tools consisting of Arcgis 10.3, QGIS 3.6, GeoDa, SPSS statistics 20, a questionnaire, and a digital camera. A few methods were used including Scalogram, Global and Local Moran Index, Logistic Regression, The Hybrid Method of Analytical Hierarchy Process (AHP) and SWOT (Strengths, Weaknesses, Opportunities, and Threats) (AWOT). The result showed that in 2020 and 2021, four of the sub-districts were comparatively well developed, four others were considered developed (hierarchy2), and 8 remaining sub-district were less developed. From 2010-2020, the paddy field was converted to other land uses by 3.529 ha clustered in the Balige subdistrict. The driving factors of paddy field conversion include distance to near central government, distance to near market, and spatial planning. We found three suitability classes in this district, namely S2 at 7.787 ha which were dispersed in all directions, S3 at 7.287 ha that were clustered in west Toba, particularly the Laguboti sub-district and its neighbors, N at 1.579 that were clustered in east Toba. The priority of paddy field protection in Toba Regency could be divided into three classes: priority 1 by 10.305 ha, priority 2 by 1.784 ha, and priority 3 by 4.632 ha. The main strategies to control paddy field conversion in Toba Regency include land protection regulation, the subsidy of production input to farmers, use of the local government budget to build agricultural infrastructure.