Effects of Soil Compaction and Relative Light Intensity on Survival and Growth Performance of Planted Shorea macrophylla (de Vriese) in Riparian Forest along Kayan Ulu River, Sarawak, Malaysia

Aina Nadia Najwa Mohamad Jaffar,Mohd Effendi Wasli,Hamsawi Sani,Mugunthan Perumal,Jonathan Lat

doi:10.1155/2018/6329295

Aina Nadia Najwa Mohamad Jaffar, Mohd Effendi Wasli + Show 3 more

Open Access

https://doi.org/10.1155/2018/6329295

Copy DOI

Abstract

A study was conducted in riparian forest along Kayan Ulu River, Sarawak, Malaysia, to investigate the effects of soil compaction and relative light intensity (RLI) on survival and growth performance of planted Shorea macrophylla. The study sites were stands reforested in different years (1996: SPD96; 1997: SPD97; 1998: SPD98; 1999: SPD99). The survival, growth performance, soil compaction, and RLI were measured. SPD96 trees had the highest survival (84%) and showed the most favourable growth. Average height, mean annual increment in height, and RLI were highest in SPD97 while mean annual increment in volume was highest in SPD98. Soil compaction in SPD98 and SPD99 was higher as compared to SPD96 and SPD97. This was due to the compacted soils caused by anthropogenic activities and natural causes (wet soils) in riparian forest along Kayan Ulu River at shallow depth. High survival and favourable growth performance of S. macrophylla were influenced by the edaphic factor with special reference to less compacted soils and high RLI. Stepwise multiple regression demonstrated significant effects of soil penetration resistance at the depth of 0-30 cm and RLI on mean annual increment in diameter. Further ecological studies on other environmental factors should be implemented to draw up a Dipterocarp planting scheme for the future restoration of riparian ecosystem.

Highlights

Southeast Asia’s tropical rainforest which includes a portion of Borneo Island is considered as one of the world’s biodiversity hotspots [1]
Information on the Reforestation Sites. This assessment was conducted in riparian forest at Sampadi Forest Reserve (N01∘34󸀠13󸀠󸀠, E109∘53󸀠12󸀠󸀠) which is along Kayan Ulu River, Lundu, Sarawak, and is approximately 72 km from the city of Kuching (Figure 1) [19, 20]
The survival percentage of planted S. macrophylla at various age stands is shown in Table 1 and increased with age ranging from 84% in SPD96 to 55% in SPD99

Summary

Introduction

Southeast Asia’s tropical rainforest which includes a portion of Borneo Island is considered as one of the world’s biodiversity hotspots [1]. The richness of species in the tropical rainforest is undergoing disturbance due to the overexploitation of forest resources for various land uses such as shifting cultivation, conversion for lands to agriculture, illegal logging activities, and clearance of forest area for development purposes These extinction instances of endangered species, disruption in the carbon cycle which might lead to global climate change, expansion of degraded lands, and reduction of soil productivity may negatively affect the ecological health of the tropical forest [2]. Considering such a situation, it is crucial to conserve forest resources in a sustainable manner [3]. Enrichment planting is the most common technique used on degraded forests without eliminating the existing valuable

Objectives

Methods

Results

Conclusion