Characterizing a Populated Riparian Zone

Abstract

Developments adjacent to river, over the years, have impacted the ecological systems along riparian zones. This paper is to explore the changes occurring in a populated riparian zone. For over 35 years, the nipah swamps along the study site at the edge of Kuching city, Sarawak, Malaysia are subjected to human disturbances. Once a nipah forest is dominated by Nypa fruticans, the study site is being replaced by Sonneratia caseolaris-a mangrove forest. Both plants are indigenous to Southeast Asia region. We observe in the study site that Nypa fruticans, habitually a dominant species, is weakened when human disturbances are high, and leads to event taken over by Sonneratia caseolaris. We point out that Sonneratia caseolaris behaves intrusively rather than neighborly in disturbed systems. Here, we suggest that the plant also has high resistance towards human disturbances. This is a growing behavior contradictory to reports of Sonneratia caseolaris in natural systems. KeywordsMangrove, Nipah Swamp, Nypa fruticans, Sonneratia caseolaris, Urban River BackgroundHuman activities increasingly either degrade ecosystems, leading to harsher abiotic conditions and/or more limited dispersal of the species originally present; or introduce new species which alter the biotic environment and potentially reduce chances for system redevelopment. In both situations, novel ecosystems can be expected [1]-[3]. This paper is to gain understanding of the mentioned changes in a populated riparian zone because this would allow people to identify, proactively address specific concerns and monitor changes over time.Riparian zones are the interfaces between terrestrial and aquatic ecosystems, and host a wide array of plant and animal life [4]- [6]. Understanding of terrestrial-aquatic interactions is critical for assessing ecological effects of development because human settlements are often clustered near such areas [7] Study SiteLocated at the eastern edge of Kuching city, the study site is near Muara Tabuan Light Industrial Park. The industrial park is beside the confluence point of tidally-influenced Tabuan and Kuap Rivers (Figure 1). Earliest development of this area was traced to 1978 with the construction of a manufacturing plant, followed by housing estates and villages nearby. It was once a nipah swamp, characterized by nipah palms or Nypa fruticans lining the banks of Kuap River. For over 35 years, the nipah swamps along the two rivers are subjected to human interventions [10]. It is for this reason that makes this area an ideal site to have an investigation on its characteristics. A total of 22 polygons of 100 m × 100 m are delineated along the riparian strip for analysis. Some intact nipah swamps are still thriving on the opposite bank of the industrial park, allowing comprehensible comparison to the polygons being studied. Field InvestigationBorneo Island is one of the many islands dotted the western Indo-Pacific region. As such, the typical mangrove zones depicted in Figure 2 holds true for the study site [11]. The site i...