Seedling Growth and Quality of Avicennia marina (Forssk.) Vierh. under Growth Media Composition and Controlled Salinity in an Ex Situ Nursery

Abstract

Avicennia marina (Forssk.) Vierh. is an important mangrove species that inhabits the outermost zone of mangrove forests, but it has been shown to have a poor ability to regenerate due to its low seedling quality. We conducted a study to evaluate the specific growth requirements of A. marina, i.e., medium and salinity level. Germinated seeds were transplanted to pots filled with media, i.e., silt loam (M1), loam (M2), sandy loam (M3), or sand (M4), with various salinity levels 5 (S1), 5–15 (S2), 15–25 (S3), or 25–35 ppt (S4). Survival rate, growth, biomass partition, and seedling quality were observed for 14 weeks after transplanting the seeds. The highest rate of seedling survival was found in the S2 condition, and higher concentrations of salinity lowered the survival rates. The S1 treatment promoted the initial 8 week growth of the seedlings. Growth medium had no significant effect, except on the survival rates grown in M4. Growth medium composition had no distinct effect on seedling growth. The S2 and S3 treatments induced better growth (in terms of shoot height and root length) and resulted in high-quality (i.e., Dickson quality index) seedlings in any type of medium. The S3 treatment increased the seedling quality in M1 and M4, whereas the S4 treatment only benefited seedlings in the M4 medium. According to the results, a specific range of salinity (5–15 ppt) with circulated water in any type of medium is recommended for the establishment of an ex situ nursery for the propagation of A. marina, in contrast to the general range of salinity (4–35 ppt) stated in previous references.

Impacts of different salinity levels on seedling growth and survival of black mangrove (Avicennia germinans)

“…Production is also influenced by salinity, and at the stage of development, an increase in salinity reduces height and growth, particularly in Avicennia spp. (Whigham et al 2009;Nguyen et al 2015;Budiadi et al 2022).…”

“…Further reductions in leaf life span and the incapacity to sustain fresh leaf production result in a significant drop in leaf area per plant at very high salinity. Reduced leaf area can be caused by salinity and nitrogen levels (Sobrado 2000;Suárez and Medina 2005;Budiadi et al 2022).…”

“…Salt secretion is a very active system that comprises several metabolically regulated phases. As a result, declines in the solutes transported to leaves were more relevant in hypersaline circumstances (Ball 2002;Basak et al 2004;Budiadi et al 2022).…”

Diversity, composition, structure and canopy cover of mangrove trees in six locations along Bintuni riverbank, Bintuni Bay, West Papua, Indonesia

“…There were a number of factors affecting the higher Avicennia sp., distribution in these two locations, one of which was the low rate of substrate sediment that increase the potential of life growth (Affandi et al 2010). Therefore, even though the Avicennia sp., is known as a salt-tolerant species and tends to adapt to water fluctuation (Chen and Ye 2014), the species is unable to grow longer due to a low root penetration system and does not produce fibrous mud, poor ability to regenerate and susceptible to the extreme micro-climate attributes, in particular close to the estuary (Budiadi et al 2022). Therefore, it can be assumed that there was a pattern of mangrove diversity zonation among the six locations which is obviously influenced by environmental factors, such as the ability to tolerate water salinity, the capability of growing with seawater inundation, etc (Irawan et al 2021).…”

A preliminary survey of hymenopteran fauna of Iranian mangrove ecosystem, northern part of the Persian Gulf and Oman Sea

“…The mangrove ecosystem can also prevent sedimentation, stabilize the habitat, and maintain nutrient cycles, thus providing protection to the inland ecosystem against the erosive force of the sea. Thus, the economic productivity of coastal and terrestrial communities relies on the maintenance of the ecological sustainability of mangroves (Budiadi et al, 2022). The mangroves are mainly threatened by natural (pest damage, storms, acid rain) and anthropogenic (oil spills, industrial wastes, infrastructure development) factors (Erfanifard, 2022).…”