Zooplankton species composition and diversity in the seagrass habitat of Lawas, Sarawak, Malaysia

Abstract

Seagrass habitats are considered to be some of the most biodiverse ecosystems on the planet and safeguard some ecologically and economically important fauna, amongst which are some globally threatened species, including dugong. Malaysian seagrass ecosystems are not widespread, but their existence supports some significant marine fauna. A rigorous zooplankton study was conducted from May 2016 to February 2017, in the seagrass habitat of Lawas, Sarawak, Malaysia, to examine their temporal composition and diversity, together with their ecological influences. A total of 45 zooplankton species from 13 significant groups were recorded in the seagrass habitat. The population density of zooplankton ranged between 2,482 ind/m³ and 22,670 ind/m³ over three different seasons. A single zooplankton copepod was found to be dominant (47.40%), while bivalves were the second largest (31.8%) group in terms of total abundance. It was also noticed that the average relative abundance (0.62) and important species index (62.08) of copepods were higher than for other groups that exist in the seagrass meadow, whereas copepod Parvocalanus crassirostris showed both the highest average relative abundance (0.41) and the highest important species index (41.15). The diversity (H') and richness index of the intermediate season were found to be highest due to favourable physico-chemical conditions. Within the referred seasonal cluster, the wet and dry seasons were almost similar in terms of species abundance, while the intermediate season was distinct, with high species diversity backed by ANOSIM analysis results. Copepod and bivalves formed one group with a common similarity level of 0.80. The CCA (Canonical Correspondence Analysis) model established that abiotic factors, especially turbidity, NO2, rainfall, dissolved oxygen and pH were significantly correlated with abundance of individual groups of zooplankton. Zooplankton assemblage and abundance in Lawas were found to be very rich in multiple seasons, indicating that the productivity of uninterrupted seagrass habitat might be high and the system rich in biodiversity.

Diversity and Community Structure of Zooplankton in Homestead Ponds of a Tropical Coastal Area

“…The highest abundance of zooplankton was 346.14 ± 7.22 ind./L, and the lowest was 211.52 ± 11.01 ind./L in the homestead ponds of the study area. A similar abundance of zooplankton was found by [50], which was relatively lower than that of the other studies [41,42,46,47]; this may be due to differences in the ecosystems as well as lack of feeding and fertilization in the studied homestead ponds [38]. The mean abundance of the zooplankton was found to be higher (301.19 ± 40.55 ind./L) in February and lower (293.02 ± 21.12 ind./L) in December in the present study.…”

“…Bosmina sp and Mesocyclops sp, indicates a high amount of suspended material in the water body. The zooplankton communities identified from Lakshadweep Archipelago, India (56 species, 7 groups) [41], from a seagrass habitat (45 species, 13 groups) [42] and a man-made lake (27 species, 3 groups) in Malaysia [43], from the maritime channel systems in the Bay of Bengal (32 species, 11 groups) [1], and from a salt marsh estuary, Cox's Bazar (33 species, 11 groups), in Bangladesh [44] were far more numerous than those in the present study, which can be attributed to diversified ecosystems. However, several previous studies have recorded a similar number of zooplankton species in brood ponds (11 genera, 6 groups) [45], Kaptai Lake (10 genera, 3 groups) [46], and aquaculture ponds (9 genera, 4 groups) [47].…”

Diversity of fish and macrobenthos at the coastal area of Tanjung Kidurong Power Plant (TKPP), Sarawak, Malaysia

“…The cluster analysis of fishes revealed two distinct clusters; the closest station to the power plant and SEB4 formed one cluster; whereas, station SEB2 and SEB3 formed another cluster, indicating that the number of fishes in each cluster was nearly identical. Different research groups performed similar cluster analysis, habitats and other groups of the organism (Al-Asif et al, 2020; Johan et al, 2020;Ismail et al, 2021).…”

Trends in Seagrass Research and Conservation in Malaysian Waters

“…The overall seagrass biodiversity in Johor was assessed by Sabri et al [72]. Japar Sidik & Zakaria [73] reported the cause of purple colo- [94]; 12 [95]; 13 [96]; 14 [97]; 15[27]; 16 [4]; 17 [99]; 18[62]; 19 [100]; 20 [28]; 21 [101]; 22 [102]; 23 [61]; 24 [103]; 25 [104]; 26 [105]; 27 [106]; 28 [107]; 29 [30]; 30 [108]; 31 [109]; 32[39]; 33 [110]; 34[63]; 35 [111]; 36 [112]; 37 [113]; 38 [65]; 39 [114]; 40 [115]; 41[59]; 42 [116]; 43 [117]; 44 [118]; 45 [119]; 46[60]; 47 [76]; 48 [123];49 [121]; 50 [122]; 51 [120]; 52 [75]; 53 [58]; 54 [74]; 55 [73]; 56 [72]; 57 [124]; 58 [125]; 59[70]; 60 [126]; 61[51]; 62 [127]; 63 [128]; 64[50]; 65[69]; 66 [18]; 67…”

“…However, the first published documents on seagrass-associated fauna were found in 2004 by Mohammad-Noor et al [41] and the number of publications on this topic has grown over time. Sea cucumbers from Penang island [93,146], zooplankton from Lawas, Sarawak [94], dugong feeding grounds from the Sibu Archipelago, Malaysia [87], and Molluscan communities from Penang, Malaysia [95] were all reported in recent documents. The previously published documents suggested that fauna, for instance, fishes [4,47,48,97,104,106,142,[147][148][149][150], different fish larvae [131,[151][152][153][154][155][156][157][158][159][160] [138,[172][173][174], porcellidiidae [124], crabs [175,176], polychaeta [170], seahorse [111,177], plankton [97,101,132,135,[178][179][180][181], dugong…”