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1

Observation of Coral Reef and Macroalgae Competition in the Sempu Strait, Malang

Isdianto Andik, Kurniawan Andi, Wicaksono Agus Dwi, Marhaendra Quanta Nur Ihza, Putri Berlania Mahardika, Fathah Aulia Lanudia, Asadi Muhammad Arif, Luthfi Oktiyas Muzaky, Pratiwi Dwi Candra, Harahab Nuddin

Journal of Ecological Engineering

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2023

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Vol. 24, nr 10

174--184

EN

Competition for space between coral reefs and macroalgae has a significant impact on coral cover and, consequently, on the sustainability of coastal ecosystems. This study aimed to ascertain the Sempu Strait’s substrate coverage, dominant coral reef lifeform, coral-macroalgae competition, and water quality. The Underwater Photo Transect method and the CPCe software are used to monitor coral reefs. The condition of the approximately 11.5% of living corals was deemed to be substandard. The western portion of the Sempu Strait is dominated by encrusting, branching, and massive corals, whereas the eastern portion is dominated by Acropora corals. Temperature varied between 26 and 35 °C, salinity varied between 17 and 35 ppt, pH varied between 7 and 8, water clarity varied between 2.25 and 2.73 m, and dissolved oxygen varied between 6.28 and 6.71 mg/L. Competition between corals and macroalgae is observed at multiple stations, including Banyu Tawar, Waru-Waru, and WatuMeja. This phenomenon can be attributed to the presence of suitable substrates such as sand, rubble, and pebbles, as well as favorable seasonal conditions and water quality that promote the growth of macroalgae. Essentially, macroalgae grow more rapidly than corals, resulting in competition for growing space.

2

Humped Relationship between Herbaceous Species Richness and Biomass Reveals a Potential for Increasing Productivity in a Temperate Desert in Central Asia

Tao Ye, Zhou Xiao-Bing, Zhang Jing, Yin Ben-Feng, Wu Nan, Zhang Yuan-Ming

Polish Journal of Ecology

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2020

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Vol. 68, nr 1

67--83

EN

Species richness-biomass relationship has become a primary focus in plant community ecology. The most commonly reported pattern of species richness and biomass is the humped relationship with a peak in richness at moderate biomass, although negative, positive, or no relationships exited in some cases. However, the richness-biomass relationship in the temperate deserts of Central Asia, where herbaceous species with different life forms are abundant, remains unclear. In this study, 21-214 plots with herbaceous richness and aboveground biomass for each of four plot sizes (0.25, 25, 100, and 400 m2) were surveyed in early summer and early autumn in the Gurbantunggut Desert, China. Linear and quadratic regressions were employed to examine the richness-biomass relationship and the location of the richness peak. Significantly unimodal species richness-biomass relationships were observed in all plot sizes and seasons (except for 0.25 m2 plot in summer). In most cases (9/11), the biomass at the richness peak was higher than half of the biomass range. Meanwhile, the percent of sampling plots where the biomass was less than the peak was considerably greater than 50% (72.7 to 100%) in all cases, and nine of them were more than 95%, indicating strong interspecific coexistence and weak interspecific competition. In conclusion, under the background of increasing precipitation and nitrogen deposition, the humped richness-biomass relationship and the high percent of sampling plots with low biomass jointly revealed a huge potential for increasing productivity, which is crucial for the carbon fixation and ecosystem stability in deserts of Central Asia.

3

The Influence of Vegetation Structure on the Composition of the Seed Rain and Seedling Pool in Abandoned Molinion caeruleae Meadows

Kostrakiewicz-Gierałt K.

Polish Journal of Ecology

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2017

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Vol. 65, nr 2

269--284

EN

The investigations of the effect of different habitat conditions on the composition of the seed rain and seedling pool were conducted in the years 2014 and 2015 in abandoned patches of Molinion caeruleae dominated by small-stature meadow taxa (patch I), tall-growing grasses (patch II), as well as shrubs and trees (patch III). Observations showed that along the successional gradient the seed rain and seedling pool diminishes. The prevalence of perennials and native taxa in the seed rain and seedling pool occurred in all the study sites. Moreover, in the propagule and seedling pools of all the patches hemicryptophytes and meadow taxa prevailed but their number decreased in successional sites. Also, the abundance of ruderal and grassland taxa decreased gradually, at expense of number of forest species. Zoochorous species prevailed in the seed rain and seedling pool of all patches. Number of hydrohorous species decreased in successional patches, while the abundance of species with other dispersal modes were similar. Irrespective of patch character, the species producing propagules with medium size dominated in the seed rain and seedling pools, whereas a significant decrease of number of small-seeded species was noticed only in the seedling pool. Despite the diminishing of the seed rain and seedling pool along the successional gradient, the gap creation might be a very effective way of active protection of Molinion caeruleae meadows. However, the gap colonisation requires permanent monitoring to avoid further spreading of undesired taxa.

4

Altitude Patterns of Leaf Carbon Isotope Composition in a Subtropical Monsoon Forest

Pan S., Zhang W., Zhao M., Li Y., Xu S., Wang G.

Polish Journal of Ecology

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2015

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Vol. 63, nr 4

512--522

EN

Leaf carbon isotope composition (δ13C) of both vascular and non-vascular plants were investigated in order to assess their variability along an altitude gradient (414, 620, 850, 1086, 1286 and 1462 m) from a subtropical monsoon forest located at Mt. Tianmu Reserve, eastern China. Leaf δ13C values of all plant species ranged from -34.4 to -26.6‰, with an average of -29.8‰. There is no significant difference in leaf δ13C between vascular plants and mosses, however, trees had significantly higher δ13C values than herbs. For pooled data, leaf δ13C was positively correlated with altitude. Leaf δ13C was significantly and negatively correlated with annual mean temperature and atmospheric pressure, while it was significantly and positively correlated with soil water content. Furthermore, there was no relationship between leaf δ13C and soil nitrogen content or soil phosphorus content. The altitudinal trend in leaf δ13C is the consequence of the interaction between temperature, atmospheric pressure and soil water content.

5

Soil seed bank and extant vegetation of a dry valley

Li Y., Bao W., Wu N.

Polish Journal of Ecology

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2011

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Vol. 59, nr 3

507-522

EN

Although crucial for guiding vegetation improvement efforts, soil seed bank (SSB) and extant vegetation (EV) in dry valleys remains poorly understood. A germination method and field surveys were applied to address this problem and investigate the characteristics of SSB and corresponding EV of eight sites across the dry Minjiang River valley in Southwest China. Furthermore, the relationships between SSB and EV were compared to provide guidance for vegetation enhancement. Eight sites were classified into two groups - central and transitional sites that differ according to moisture conditions. Seed density and species richness in SSB were lower in less moist central sites compared with those in more moist transitional sites of the valley as well as the coverage of the community. Moreover, species richness and litter thickness were lower in central sites. Comparing SSB strategies of species from eight sites, transient strategy was the most frequently observed category, followed by short-term persistent and long-term persistent strategies. In terms of both SSB and EV, the most abundant life forms were hemicryptophytes, intermediate phanerophytes, and therophytes, whereas less abundant were chamaephytes and cryptophytes. Low Sorenson.s similarity indices (22.32%) and significantly negative Kendall.s correlation in species composition indicate that species composition of SSB was not closely related to corresponding EV for each of the eight sites. Low seed density, especially the lack of viable dominant shrub seeds, dominant transient SSB strategy species, and low correspondence in species composition between SSB and EV imply that the potential for vegetation enhancement in the dry valley is weak, particularly in less moist central sites. To preserve the good EV of more moist transitional sites and introduce seeds of dominant species to improve poor EV in central sites, EV is likely to be a feasible standard for improving vegetation in dry valleys.

6

Road-side herbaceous vegetation : life history groups and habitat preferences

Sera B.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

69-79

EN

The study examine s the vegetation diversity (235 herbaceous species) in variable road-site types in terms of life history components (life traits) like life form, type of pollination, seed dispersal, spreading ability, life strategy according to Grime's classification, and in terms of habitat preferences using Ellenberg's indicator value (in relation to light, temperature, moisture, nitrogen, soil pH and soil salinity). Plants registered as alien species were evaluated also according to invasive status, level of abundance, introduction mode and land use habitat. Study localities (9 sites) were situated in the Ceskomoravska highlands and the South Bohemian regions (Czech Republic). The plant species were recorded in the bands (width in range of 1.5-3.0 m) along the verge of two types of roads (motorways with median stripes) and secondary roads (II and III classes). In total - road length of about 15 km and the total area of roadside vegetation of about 8 ha were surveyed. The annual/therophyte species with a tendency to seed dispersed by wind, preferring a light and dry habitat, and having the RC (competitiveruderal) life strategy were mainly found along the motorways. It means that road verges along motorways are quite insolated and constitute the dry habitats, probably suitable for ruderal, weedy, non-native, and invasive species. On the contrary, species with a tendency to vegetative reproduction and the C (competitive) strategy occur mainly along the secondary roads. It seems that the secondary roads are alternative habitats for grassland flora. Species occurred on the verges of the secondary roads do not belong to the particular group of the life traits. The salt tolerant species Puccinellia distans (Jacq.) Parl. was found along all types of roads. Almost 24% of all recorded herbaceous species growing in road-sites were alien species.

7

Leaf nitrogen resorption pattern along habitats of semi-arid sandy land with different nitrogen status

Luo Y., Zhao X., Zuo X., Zhang J., Liu R., Wang S.

Polish Journal of Ecology

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2010

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Vol. 58, nr 4

707-716

EN

To assess nitrogen (N) resorption patterns in semi-arid sandy land, N concentrations in green leaves (N[g]) and senesced leaves (N[s]) of 35 species of shrubs and herbages were measured along habitats of decreasing soil total N (0.54 to 0.041 g g[^-1] d.w. of top soil level) in Horqin Sandy Land (Inner Mongolia, China). These habitats are following: inter-dune grassland (IDG), fixed sand dune (FD), semi-fixed sand dune (SFD), semi-mobile sand dune (SMD), and mobile sand dune (MD) were considered. Results showed that Ng and Ns (i.e. nitrogen resorption proficiency, NRP) increased and leaf nitrogen use efficiency (NUE) decreased significantly with increasing soil N status across the above habitas, but nitrogen resorption efficiency (NRE) was not affected. The levels of N[g], N[s] and NUE experience two stages across habitats: first, there were low N[g] and N[s and high NUE in MD and SMD; second, there were high N[g] and N[s] and low NUE in IDG, FD and SFD. Plants from IDG, FD and SFD had incomplete N resorption during foliar senescence, but plants from MD and SMD had complete N resorption. Leaf NRE was determined by life forms which had no significant effect on N[g] but on N[s] and NUE. For all plants in the five habitats, NRE and NUE decreased with the sequence of grass, herb, shrub, while Ns showed a contrary tendency. Plants from strong N limitation habitats did not show higher NRE, but showed higher NRP and leaf NUE, so NRP was a more sensitive indicator of changes in N status than NRE. In conclusion, Leaf N resorption patterns were mainly determined by soil N status across habitats, and there were some consistent patterns among life forms.