Soil Morphological and Physicochemical Properties at Reforestation Sites After Enrichment Planting of Shorea Macrophylla in Sampadi Forest Reserve, Sarawak, Malaysia

Abstract

Implementation of effective soil conservation management is required in order to rehabilitate and manage degraded forest land in the tropics. For the humid tropics of Sarawak, Malaysia, extensive information on the soil characteristics for rehabilitation of degraded forest lands is essential to guide future forest management programme. In this study, a preliminary assessment on the current status of the soil morphological and physicochemical properties at one of the reforestation sites in Sarawak which was established after enrichment planting of Shorea macrophylla in comparison to an adjacent secondary forest was conducted. The soil profiles in the study sites were established at the reforestation areas of different age stand (year 1996; SM96, 1997; SM97, 1998; SM98 and 1999; SM99) planted with Shorea macrophylla located in Sampadi Forest Reserve as well as existing secondary forest adjacent to the reforestation sites (secondary forest, SF). Soil profile description was conducted at each study sites and soil samples were collected from each identified soil horizon for determination of the soil physicochemical properties. The results showed that the soils in the study area consisted of mainly grey-white podzolic soils which derived from combination of sandstone, coarse-grained, humult ultisols and sandy residual parent material. According to the Sarawak Soil Classification, the morphological properties in the studied sites resemble of Bako soil series as a dominant unit in association with Saratok series in which, corresponds to Typic Paleaquults of Soil Taxonomy by USDA-NRCS Classification. The general soil physicochemical properties indicated that the soils at both reforestation sites and secondary forest were strongly acidic in nature with pH (H2O) of less than (pH < 5.5) with low nutrient status. The acidic nature of the soils might be ascribed to the presence of high exchangeable Al which concomitantly, increased the level of Al saturation of the studied soils. Observation within each soil profiles indicated that soil acidity decreased with depth, resulting in higher pH (H2O) at deeper horizons for all studied sites. For the soil total carbon and total nitrogen, soils at secondary forest depicted higher values in total carbon and total nitrogen at surface soils as compared to the reforestation sites which indicate large pool of organic matter at surface soil derived from the above vegetation. In terms of the soil physical properties, the soils observed were relatively of sandy texture and did not varied widely among the studied sites. In addition, the soil bulk density at reforestation sites was relatively higher than secondary forest due to higher penetration of roots and accumulation of organic matter contents in secondary forest. Based on the current progress of this study, it is recommended that determination on the soil characteristics should be taken into consideration as an important indicator prior or during the establishment of reforestation area in order to ensure the success of reforestation activity in tropical rainforests.

Evaluation on Soil Hardness in Riparian Forest Restoration along Kayan Ulu River, Sarawak, Malaysia

“…The bulk density (BD) value (data not shown) decreases with increasing soil penetration resistance. Thus, this trend was similar with our previous studies whereby it had lower BD with 1.36 g mL -1 at subsurface soils in SPD98 and higher content of soil organic matter as compared to the subsurface soils in SPD96 with 1.32 g mL -1 bulk density of soils (Perumal et al, 2015). High soil penetration resistance with high water content enhanced decomposition activities by soil microbes.…”

“…The area receives more than 4,000 mm of rainfall annually with annual temperatures ranging from 23°C to 33°C (Department of Irrigation & Drainage, 2016;Meteorological Department, 2016). Our previous studies reported that periodic inundation occurred with low fertility and nutrient status along the riparian forest of Kayan Ulu River, Lundu, Sarawak (Jaffar et al, 2018a(Jaffar et al, , 2018bPerumal et al, 2015Perumal et al, , 2017. The soil type in the study area constituted of combination of sandstone, coarse-grained, humult Ultisols and sandy residual parent material (Perumal et al, 2015(Perumal et al, , 2017.…”

“…Our previous studies reported that periodic inundation occurred with low fertility and nutrient status along the riparian forest of Kayan Ulu River, Lundu, Sarawak (Jaffar et al, 2018a(Jaffar et al, , 2018bPerumal et al, 2015Perumal et al, , 2017. The soil type in the study area constituted of combination of sandstone, coarse-grained, humult Ultisols and sandy residual parent material (Perumal et al, 2015(Perumal et al, , 2017. The reforestation sites were previously logged-over in the past 40 years and most of the forests have lost their original structure of soils (Jaffar et al, 2018b).…”

“…With regard to the impact of compaction on practical forest management issues, most report and review forms such as those of Batey (2009);Hattori et al (2013); Ishizuka et al (1998) were available. Our previous studies have been conducted in restoration sites to examine different aspects of the soil properties existing in the riparian ecosystem (Jaffar, Wasli, Perumal, Lat & Sani, 2018a, b;Perumal, Wasli, Ho, Lat & Sani, 2015;2017;Wasli et al, 2014). This study was conducted to determine the potential of indigenous species in relation to the soil hardness for future forest restoration strategies along the riparian ecosystem.…”

Influences of inorganic and organic fertilizers to morphological quality attributes of Shorea macrophylla seedlings in a tropical nursery

“…In the humid tropics of Borneo, Shorea macrophylla (de Vriese) P.S. Ashton is mainly chosen on the basis of its socio-economic and ecological importance as one of the common indigenous tree species used for tropical forest rehabilitation and reforestation programs in Sarawak, Malaysia (Perumal et al 2015(Perumal et al , 2017a. This endemic riparian species, locally known as "Engkabang jantong" (Light Red Meranti) (in Malaysia) and "Tengkawang Hantelok" (in Indonesia) belongs to the family of Dipterocarpaceae, the most important family of tropical rainforest trees in Southeast Asia (Utomo et al 2018).…”