BIODIVERSITAS ISSN: 1412-033X Volume 17, Number 2, October 2016 E-ISSN: 2085-4722 Pages: 409-416 DOI: 10.13057/biodiv/d170202 Soil and leaf nutrient status on growth of Macaranga gigantea in secondary forest after shifting cultivation in East Kalimantan, Indonesia DWI SUSANTO1,, DADDY RUCHIYAT2, MAMAN SUTISNA2, RUDIANTO AMIRTA2 1Department of Biology, Faculty of Mathematic and Natural Science, Universitas Mulawarman. Jl. Barong Tongkok No. 4, Gunung Kelua, Samarinda Ulu, Samarinda-75123, East Kalimantan, Indonesia. Tel./Fax.: +62-541-749140, 749152, 749153, email: [email protected] 2Faculty of Forestry, Universitas Mulawarman. Jl. Ki Hajar Dewantara, Kampus Gunung Kelua, Samarinda, East Kalimantan, Indonesia Manuscript received: 31 December 2015. Revision accepted: 1 May 2016. Abstract. Susanto D, Ruchiyat D, Sutisna M, Amirta R. 2016. Soil and leaf nutrient status on growth of Macaranga gigantea in secondary forest after shifting cultivation in East Kalimantan, Indonesia. Biodiversitas 17: 409-416. Macaranga gigantea is an important pioneer plant species in the tropical secondary forest of Kalimantan and as far the attractive wood species was not commercially cultivated. This study aims to determine the soil and nutrient status on growth of M. gigantea in the secondary forest particularly after shifting cultivation activity. For this purposes, the observation plots with 50m x 50m sizes were made and measured to collect the data of diameter, height, soil conditions and leaf nutrient concentrations (N, P and K) of M. gigantea in different ages of natural growth. A simple linear correlation analysis was used to determine the relationship of plant growth with the leaf and soil nutrient concentrations as well. The results showed that the soil condition on growth of M. gigantea has the average at pH 4.7, CEC 5.57 meq/100g, base saturation 30.22%, and the concentration of soil nutrients were 0.062±0.015% (N), 12.65±4.9 ppm (P), and 57.76±33 ppm (K). We also found that the leaf nutrient concentration was 1.94±0.13% (N), 0.22±0.08% (P) and 0.66±0.27% (K), respectively. Moreover, the highest growth of diameter was found from the 6 years old of plant (27.88 m). The annual yield of diameter and high were 4.65 cm year-1 and 2.96 year-1 and it was gradually decreased until the 10 years old of plant. The negative correlations was observed from the soil nutrient K and growth of diameter and high of M. gigantea (r=0.95, p< 0.05). The positive correlation was observed from the P and K content in the leaf of plant and growth of M. gigantea (diameter, height and volume increment, p<0.1). We suggested that phosphorus and kalium content was play an important roles on the growth of M. gigantea and this nutrient factor should be considered well when this species will be cultivated for the commercial purposes in the future. Keywords: Macaranga gigantea, nutrient status, soil condition, secondary forest INTRODUCTION land so that the land can be fertile again and replanted (Lahji et al. 1992; Imang et al. 2008). Imang et al. (2008) Shifting cultivation or slash-and-burn farming or swidden classified fallow periods among the Kenyah in four agriculture, is an age-old and prevailing subsistence categories commonly used at field sites: shrub vegetation farming practice in the tropical regions, and is one of the (0-2 years), young secondary forest (5-8 years), old traditional practices of forest and land management (Imang secondary forest (more than 9 years), and primary forest. et al. 2008; Inoue et al. 2010; Comte et al. 2012; Li et al. During the fallow period, soil fertility is regenerated 2014). Generally, shifting cultivation involves three through naturally occurring processes. The different essential features: (i) the clearing of natural vegetation, (ii) mechanisms are partly related to build-up of nutrients in a cropping period, usually one to three years, and (i) iia plant biomass, litter layer and soil organic matter during the fallow period, 10-20 years, during which the land is succesional reforestation under the fallow period (Gauguin abandoned to natural vegetation. Usually the fallow period et al. 2002). The accumulation of nutrients in plant biomass must be longer the cropping period. Traditionally, in many is affected by soil fertility and crop species. When areas, it is 10-20 years or more, but with increasing compared, relatively fertile Inceptisol soil accumulated population density, the fallow period will decrease considerably more nutrients than the less fertile Oxisol. A dramatically (Gauguin et al. 2002). Shifting cultivation two year Piper aduncum fallow accumulated twice as much system adopted by the Dayak Kenyah people in Samarinda, nitrogen (N), three times as much phosphorous (P), almost East Kalimantan, Indonesia an area of forest is cleared seven times as much potassium (K) and twice as much usually rather incompletely, the debris is burnt, and the calcium (Ca) and magnesium (Mg) than did a two year land is cultivated for a few years-usually less than five Imperata cilindrica fallow (Noordwijk et al. 2008). years-then allowed reverts to forest or secondary vegetation Macaranga gigantea is a fast-growing pioneer species (fallow period) before being cleared again. The average of in secondary tropical rain forests, and abundantly in the fallow period in Pampang Village, Samarinda was 6-10 open mixed dipterocarp forests after shifting cultivation years and forest reopened limited to young secondary (Lawrence 2001; Lawrence 2005; Kiyono and Hastaniah forest. The purpose of this shifting cultivation is to rest the 2005; Susanto et al. 2015). Imang et al. 2008 reported that 410 BIODIVERSITAS 17 (2): 409-416, October 2016 Kenyah farmers also recognize some dominant species in Therefore, here in this research we focus our work on secondary forests (fallow period) that indicate the land is soil and leaf nutrient status of M. gigantea in fallow period fertile or not fertile for rice cultivation (cropping period). of shifting cultivation areas. By obtaining information Macaranga is important indicator species of trees in young about soil and leaf nutrient status of this plant, expected to and old secondary forests. When the species found are support if this species will be cultivated for the commercial dominant and grow well in a certain area, it means that the purposes in the future. land is fertile enough for cropping period. Information about flowering, fruiting and seed germination also has been reported by Susanto et al. (2016). On the other hand, MATERIALS AND METHODS M. gigantea has not yet been cultivated and information about soil, leaf nutrient status, growth and its correlation Study area from naturally succession in various tread and age in This research was conducted in Pampang, Sungai secondary forests is not yet known. Siring (village of Dayak Kenyah), Samarinda, East One of approaches in determining fertilizer Kalimantan, Indonesia. It was located between the requirements on plants which can be applied properly is coordinates of 00020’15.4”-00021’58.8” South and soil analysis. Plant tissue analysis is more practical to 117013’46.6”-117014’11.0” East (Figure 1). The average of determine nutrient status on plant than other methods. Plant annual rainfalls (2003-2013) was 2423 mm, the highest tissue generally analyzed is leaf. Nutrients in leaves not annual rainfall interception was 2757.5 mm in 2008. The only have a role in photosynthesis but also represent plant highest monthly rainfall interception was in April (288.3) nutrient status. Leaves also consist of tissues which always and the lowest was in August (115.3 mm). Wet period available for analysis of plant nutrient status. Leaf analysis occurs between 9-12 months, while dry period occurs has been used as indicator in nutrient diagnosis and as basic between 0-3 months. Average monthly temperature was recommendation for fertilizer application on fruit crops at 27.50 and average air humidity was 82% (Anon. 2012; some countries (Smith 1962; Leece 1976; Shear and Faust Susanto et al. 2016). Soil and leaf nutrient analysis, and 1980; Liferdi et al. 2008). Kim et al. (2015) reported the data analysis were conducted in the Soil Science foliar N and P concentration could be used as a parameter Laboratory at the Faculty of Forestry and Plant Physology to assess the nutrient environments of tree species restored Laboratory, Faculty of Mathematics and Natural Sciences, in a fire-disturbed urban forest. Singh (2006) also reported Universitas Mulawarman, Samarinda, East Kalimantan, that the growth rates (height, diameter and volume Indonesia. The research was conducted from July 2011 to increment) were positively related to foliar N and P January 2012. concentration. Figure 1. Map of study area in fallow period shifting cultivation at Pampang Village Samarinda, East Kalimantan SUSANTO et al. – Growth of Macaranga gigantea, leaf nutrient and soil status 411 Procedures Correlation between soil N, P, K concentration (X) with Research in the area of fallow periods shifting leaf N, P, K concentration and growth of M. gigantea (Y) cultivation begins by conducting interviews with land was explored through regression analysis, for significance owners (farmer) to obtain information about shifting through a two-tailed Student’s t-test (p= 0.05-0.10). cultivation cycles, location and age of fallow lands. For each age fallow land made one plot size of 50 m x 50 m. Coordinate point is determined using GPS, then measuring RESULTS AND DISCUSSION the following: number of trees M. gigantea, diameter and height of trees, sampling the soil and leaf of M. gigantea. Soil chemical properties Results of soil chemical analysis showed that the soil Measurement of diameter and height M. gigantea pH range between 4.4-4.7 with an average of 4.63 ± 0.11 On each plot was measured M.