Peat soil quality index and its determinants as influenced by land use changes in Kubu Raya District, West Kalimantan, Indonesia

Abstract

Nusantara RW, Aspan A, Alhaddad AM, Suryadi UE, Makhrawie, Fitria I, Fakhrudin J, Rezekikasari. 2018. Peat soil quality index and its determinants as influenced by land use changes in Kubu Raya District, West Kalimantan, Indonesia. Biodiversitas 19: 535-540. Tropical peatland is continuously damaged in large area in Indonesia, caused by deep and wide drains which change the ecosystem. This research was conducted to evaluate the soil quality index (SQI) based on peatland use. The research was conducted in Kubu Raya District, West Kalimantan Province, in secondary peat forest, shrubland, oil palm plantation and corn field. The variables observed in this research were subsidence, water-table level, depth of peat, bulk density, water content, porosity, organic carbon, total nitrogen, total potassium, cation exchange capacity, base saturation, ash content, available phosphorus, and exchangeable calcium, magnesium, sodium, C/N ratio and soil acidity. The results showed that SQI in secondary peat forest, shrubland, corn field and palm oil plantation were 0.40, 0.37, 0.37 and 0.37 respectively. The stepwise regression analyses showed that the variables influencing SQI were the depth of peat, water-table level, and ash content. Secondary forest had the highest level (0.74) for the depth of peat with 509 cm depth while the other sites had average level (0.41-0.43) with 108.4 cm-115.5 cm mean depth. SQI of peatland increased with the increasing depth of peat and ash content. The differences showed that land use change of peatland, from forest to plantation area would decrease its SQI.

Land use conversion from peat swamp forest to oil palm agriculture greatly modifies microclimate and soil conditions

“…On the other hand, natural peatland changes to agricultural oil palm also reduces the soil quality index as the changes affect the peat soil quality especially its peat depth, water-table depth and ash content (Nusantara et al, 2018). Change in water table depth decreases soil nutrients and affect the temperature and soil moisture of an area.…”

Kaleka Agroforest in Central Kalimantan (Indonesia): Soil Quality, Hydrological Protection of Adjacent Peatlands, and Sustainability

“…The various measured soil properties were combined into a 'soil quality index' based on a minimum data defined by [62,63] through a Principal Component Analysis (PCA) on datasets for various crops, soil types, and climates. The scores were combined to form a weighted average according to [64][65][66]:…”

Kajian Kualitas Tanah pada Lahan Gambut Terbakar di Kota Pontianak Provinsi Kalimantan Barat

“…Hasil dari penentuan indeks kualitas tanah yang dihasilkan diharapkan dapat menentukan arah pengelolaan kualitas tanah yang tepat dan pemulihan lahan untuk menjaga keberlanjutan lahan-lahan gambut. Satu diantara tujuan penentuan faktor penentu dalam kualitas lahan dapat menjelaskan upaya-upaya dalam pengelolaan lahan gambut (Nusantara et al, 2018). Tujuan penelitian ini adalah menentukan indeks kualitas tanah dan faktor utamanya pada lahan gambut terbakar dan tidak terbakar di Kota Pontianak, Provinsi Kalimantan Barat.…”

“…Hasil penelitian berbeda ditunjukkan oleh Raisei dan Pejman (2021) dimana nilai rata-rata IKT pada lahan terbakar lebih rendah sebesar 28% (0.39-0.55) daripada tidak terbakar (0.56-0.75), nilai tersebut mengindikasikan hilangnya fungsi tanah karena kebakaran lahan. Penelitian terdahulu pada penggunaan lahan gambut kebun sawit, kebun jagung dan semak belukar dengan nilai sama yaitu rendah (0,37) namun berbeda pada hutan sekunder dengan kriteria sedang (0,40) (Nusantara et al, 2018). Hal ini menunjukkan bahwa perubahan ekosistem gambut menjadi penggunaan lahan lainnya dapat menurunkan kriteria IKT-nya.…”