Distribution characteristics of microplastics in the soil of mangrove restoration wetland and the effects of microplastics on soil characteristics

Microplastics that enter the soil environment are transformed by migration and can affect soil properties, which in turn have an impact on soil function and biodiversity. In this study, we investigated the distribution of soil microplastics at different planting densities and their effects on soil properties in a mangrove restoration wetland. The results showed that the average abundance of soil microplastics in the study area was 2177.5 n/500g, with the largest proportion of 0.038-0.05 mm diameter microplastics accounting for 70.9% and the rest of the diameter microplastics accounting for less than 20%, indicating that the smaller the diameter microplastics are easy to accumulate in the wetland soil. The abundance of microplastics in the restored area by planting density was ranked as 0.5×0.5m > 1.0×0.5m > 1.0×1.0m > control area. Three microplastics, polyethylene terephthalate (PET, accounted for 52%), polyethylene (PE, accounted for 24%), and polypropylene (PP, accounted for 15%), were the most prevalent and dominant microplastics in the soils of the area. SEM images showed that fractures, tears, EDS spectroscopy showed that a large number of metals were detected on the surface of microplastics. PET can influence the distribution of soil particle size due to its adsorptive viscosity, which may affect soil structure. Apart from soil pH, all other physicochemical factors changed significantly in response to PET. Besides, the results of the CV analysis reflect that soils in vegetated areas are more susceptible to the effects of PET than bare ground soils resulting in greater variability in the properties.

Testing a theoretical framework for the environment-species abundance paradigm: a new approach to the Abundant Centre Hypothesis

The linkage between environment, a species' fitness and its abundance is central to the theory of evolution. So far, all studies of this linkage have been heuristic and empirical due to an inability to determine fitness either experimentally (independent of abundance) or theoretically (from species-environment interaction). One category of such studies involves the Abundant Centre Hypothesis which posits that a species' abundance rises to a maximum at the centre of its range. We argue that the confusing mix of results from ACH studies arises from ignoring the central premise that the abundance distribution cannot be independent of the environment. First, we employed a theoretical framework to identify an environmental context (an elevational transect; 200-2800 m in the eastern Himalayas) likely to favour ACH. We then improved upon some previously identified conceptual and methodological shortcomings of ACH studies. Using systematically collected bird data (245 species; 15867 records) from that transect we found that the community average abundance profile is symmetric, as expected by ACH. Notwithstanding which, the abundance profiles of individual species showed a small degree of asymmetry which was correlated with elevation. This elevational dependence may be due to the hard elevational limits at the lower and upper ends of the mountain, as expected from theoretical considerations. We also showed that the average abundance profile shape is close to gaussian, while ruling out uniform and inverted-quadratic shapes. This work demonstrates that selecting a particular category of environmental contexts can help in integrating theoretical tools into a field dominated by empirical studies. Such a union should spur the development of more detailed and testable theoretical models for better insights in an important field.

Assessment of water quality based on biological indices of macrobenthos: a river under pressure from tourism activities

Cijulang River is one of the leading ecotourism objects in Pangandaran, West Java Province, Indonesia. However, the river has a variety of activities that can increase the water pollution in the river such as Green Canyon cliffs tourism, ecotourism of mangrove conservation, housing, and industrial siting. Macrobenthos is one of the bio-indicators that can assess the rate of water pollution in rivers, especially their organic pollutants. Therefore, this research aims to determine water pollution status in Cijulang River Tourism by comparing various biotic indices. The study was conducted at four site sampling locations from upstream to downstream in the rainy season period and dry season period using different methods namely, line transect model, water quality assessment by biological indexing (diversity, species dominant, and family biotic), species deficit, and organic measurement. The research showed 5873 macrobenthos and divided into 27 species with an average abundance of 167 ind.m-2 and are mainly dominated by gastropod species Faunus ater (40%). They are extreme species that can live in high organic pollution and water salinity. This divided the research of quality water assessment of Cijulang River into three categories as follows: slightly polluted (score 36-46) at Green Canyon site, moderately polluted (score 50-60) at Boat Shelter and Muara Cijulang location, and highly polluted (score 66) at Nusawiru site.Keywords:RiverBio-indicatorOrganicAquatic pollution

Seasonal variation in the essential oil from Varronia curassavica Jacq. accessions

Varronia curassavica has anti-inflammatory properties because of the terpenes, α-humulene and β-caryophyllene, present in the essential oil. The objective of this study was to evaluate the influence of seasonality on the essential oil of V. curassavica accessions. Leaves from six accessions were collected from the Germplasm Bank of the Federal University of Minas Gerais over 12 months. Correlations between the essential oil content and meteorological factors were determined. Gas chromatography analysis coupled with mass spectrometry was conducted to determine the chemical composition of the essential oil. The content and chemical composition of the oil varied throughout the year. Relative humidity was correlated with accessions ICA-VC2 (-0.64) and ICA-VC4 (0.68). β-bourbonene, β-elemene, spathulenol, germacrene, caryophyllene oxide, α-humulene, and β-caryophyllene occurred in all accessions. Accession ICA-VC3 exhibited lower variation (22.17%), higher average (0.97%) essential oil, and maintained an average abundance of α-humulene greater than 2.6%, which is the amount necessary for phytotherapeutics.

Diversity and Ecological Index of Penaeid Shrimp Collected from Mangrove Area of Kuala Langsa, Aceh, Indonesia

Shrimp is a fishery product that has high economic value. However, information of diversity and ecological index of penaeid shrimp Kuala Langsa was not well reported. Thus, this study aims to determine the species, analyze the ecological index and analyze the long relationship in penaeid shrimp caught in the Kuala Langsa mangrove waters. This study used purposive sampling method, for sampling was carried out with three locations and three repetitions. The results of the identification research found three species of the Penaeus genus with a total of 144 individuals consisting of P. monodon, P. indicus and P. merguiensis species with an average abundance value per station of 0.18, 0.09 and 0.21 ind/m2, the diversity index with an average number of 0.98 is categorized as low, the uniformity index 0.9 is categorized as high and the dominance index 0.37 is categorized as low. The length and weight relationship of male and female P. monodon species showed positive and negative allometric patterns, male and female P. indicus showed the same pattern, namely negative allometric and male and female P. merguiensis showed isometric and negative allometric patterns. Shrimp is a fishery product that has high economic value

Abundance of Plankton in the Waters of Geger Beach, Badung Regency, Bali

Geger Beach is located in Peminge traditional village area, Sawangan, Nusa Dua, Bali which is a tourism area and there is seaweed cultivation managed by local people. Such human activity will affect the quality of the waters which will result in an increase in nutrients and organic matter which can further lead to changes in the structure of plankton. The purpose of this study is to find out the types of plankton and the abundance of plankton found in the waters of Geger Beach using the pour method. This research was conducted in March 2021. Sampling is conducted once a week at three observation points. The total phytoplankton species obtained as many as 32 species consisting of 6 classes, namely Bacillariophyceae (23 genera), Xanthophyceae (1 genus), Cyanophyceae (3 genera), Ulvophyceae (1 genus), Conjugatophyceae or Zygnematophyceae (2 genera), Coscinodiscophyceae (2 genera). The dominant type of phytoplankton found during the study was the Gyrosigma fasciola species in the Bacillariophyceae class. Meanwhile, the total zooplankton obtained by 11 species consisting of 5 classes, namely Maxillopoda (3 genera), Hexanauplia (3 genera), Magnoliopsida, Branchiopoda, and Copepoda (1 genus). The dominant type of zooplankton found during the study was the Cyclops sp. species in the Maxillopoda class. The average abundance of phytoplankton is 120 cells/l, while the average abundance of zooplankton is 20 cells/l. The average diversity value of phytoplankton is 2,7, while the diversity of zooplankton is 1,4. The average dominance index value of phytoplankton is 0,06, while the average zooplankton dominance index is 0,25.

Distribution and Abundances of Planktic Foraminifera and Shelled Pteropods During the Polar Night in the Sea-Ice Covered Northern Barents Sea

Planktic foraminfera and shelled pteropods are important calcifying groups of zooplankton in all oceans. Their calcium carbonate shells are sensitive to changes in ocean carbonate chemistry predisposing them as an important indicator of ocean acidification. Moreover, planktic foraminfera and shelled pteropods contribute significantly to food webs and vertical flux of calcium carbonate in polar pelagic ecosystems. Here we provide, for the first time, information on the under-ice planktic foraminifera and shelled pteropod abundance, species composition and vertical distribution along a transect (82°–76°N) covering the Nansen Basin and the northern Barents Sea during the polar night in December 2019. The two groups of calcifiers were examined in different environments in the context of water masses, sea ice cover, and ocean chemistry (nutrients and carbonate system). The average abundance of planktic foraminifera under the sea-ice was low with the highest average abundance (2 ind. m–3) close to the sea-ice margin. The maximum abundances of planktic foraminifera were concentrated at 20–50 m depth (4 and 7 ind. m–3) in the Nansen Basin and at 80–100 m depth (13 ind. m–3) close to the sea-ice margin. The highest average abundance (13 ind. m–3) and the maximum abundance of pteropods (40 ind. m–3) were found in the surface Polar Water at 0–20 m depth with very low temperatures (–1.9 to –1°C), low salinity (<34.4) and relatively low aragonite saturation of 1.43–1.68. The lowest aragonite saturation (<1.3) was observed in the bottom water in the northern Barents Sea. The species distribution of these calcifiers reflected the water mass distribution with subpolar species at locations and depths influenced by warm and saline Atlantic Water, and polar species in very cold and less saline Polar Water. The population of planktic foraminifera was represented by adults and juveniles of the polar species Neogloboquadrina pachyderma and the subpolar species Turborotalita quinqueloba. The dominating polar pteropod species Limacina helicina was represented by the juvenile and veliger stages. This winter study offers a unique contribution to our understanding of the inter-seasonal variability of planktic foraminfera and shelled pteropods abundance, distribution and population size structure in the Arctic Ocean.

Annual changes in the Biodiversity Intactness Index in tropical and subtropical forest biomes, 2001–2012

Few biodiversity indicators are available that reflect the state of broad-sense biodiversity—rather than of particular taxa—at fine spatial and temporal resolution. One such indicator, the Biodiversity Intactness Index (BII), estimates how the average abundance of the native terrestrial species in a region compares with their abundances in the absence of pronounced human impacts. We produced annual maps of modelled BII at 30-arc-second resolution (roughly 1 km at the equator) across tropical and subtropical forested biomes, by combining annual data on land use, human population density and road networks, and statistical models of how these variables affect overall abundance and compositional similarity of plants, fungi, invertebrates and vertebrates. Across tropical and subtropical biomes, BII fell by an average of 1.9 percentage points between 2001 and 2012, with 81 countries seeing an average reduction and 43 an average increase; the extent of primary forest fell by 3.9% over the same period. We did not find strong relationships between changes in BII and countries’ rates of economic growth over the same period; however, limitations in mapping BII in plantation forests may hinder our ability to identify these relationships. This is the first time temporal change in BII has been estimated across such a large region.

Comparative Secretomics Analysis Reveals the Major Components of Penicillium oxalicum 16 and Trichoderma reesei RUT-C30

In this study, the major secretome components of Penicillium oxalicum 16 and Trichoderma reesei RUT-C30 under wheat bran (WB) and rice straw (RS) solid-state fermentation were systematically analyzed. The activities of the major components, e.g., cellulase, hemicellulase, and amylase, were consistent with their abundance in the secretomes. P. oxalicum 16 secreted more abundant glycoside hydrolases than T. reesei RUT-C30. The main up-regulated proteins from the induction of WB, compared with that from RS, were amylase, pectinase, and protease, whereas the main down-regulated enzymes were cellulase, hemicellulase, swollenin, and lytic polysaccharide monooxygenase (LPMO). Specifically, WB induced more β-1,4-glucosidases, namely, S8B0F3 (UniProt ID), and A0A024RWA5 than RS, but RS induced more β-1,4-exoglucanases and β-1,4-endoglucanases, namely, A0A024RXP8, A024SH76, S7B6D6, S7ZP52, A024SH20, A024S2H5, S8BGM3, S7ZX22, and S8AIJ2. The P. oxalicum 16 xylanases S8AH74 and S7ZA57 were the major components responsible for degrading soluble xylan, and S8BDN2 probably acted on solid-state hemicellulose instead of soluble xylan. The main hemicellulase component of T. reesei RUT-C30 in RS was the xyloglucanase A0A024S9Z6 with an abundance of 16%, but T. reesei RUT-C30 lacked the hemicellulase mannanase and had a small amount of the hemicellulase xylanase. P. oxalicum 16 produced more amylase than T. reesei RUT-C30, and the results suggest amylase S7Z6T2 may degrade soluble starch. The percentage of the glucoamylase S8B6D7 did not significantly change, and reached an average abundance of 5.5%. The major auxiliary degradation enzymes of P. oxalicum 16 were LPMOs S7Z716 and S7ZPW1, whereas those of T. reesei RUT-C30 were swollenin and LPMOs A0A024SM10, A0A024SFJ2, and A0A024RZP7.

Crustacean and mollusk species diversity and abundance in the mangrove communities of Mimika District, Papua, Indonesia

Setyadi G, Rahayu DL, Pribadi R, Hartati R, Wijayanti DP, Sugianto DN, Darmawan A. 2021. Crustacean and mollusk species diversity and abundance in the mangrove communities of Mimika District, Papua, Indonesia. Biodiversitas 22: 4146-4157. A mangrove crustacean and mollusk species diversity study was carried out in four mangrove estuaries in Mimika District, Papua, Indonesia. Two locations were selected on each estuary; for each location, samples of crustaceans and mollusks were collected from 5 m × 5 m plots, and mangrove trees were recorded on 10 m × 10 m plots at a distance of 10 m, 250 m and 500 m perpendicular to the riverbank. This study recorded a total of 41 species of crustaceans and 32 species of mollusks the latter comprising three species of bivalves and 29 gastropod species. The number of crab species found was among the highest compared to similar studies in the world. The average number of species collected from each 25 m2 plot was 7.6 ± 4.2 species for crustaceans, with an average abundance of 87 ± 3.5 individuals; for mollusks, it was 3.3 ± 3 species with an average abundance of 28 ± 48.4. Crustacean abundance and species composition were influenced by inundation frequency. There was a strong correlation between the crab Parasesarma cricotum and the association of Rhizophora apiculata and Bruguiera gymnorrhiza mangroves, and Clistocoeloma amamaparense and the association of B. gymnorrhiza, R. apiculata, and Bruguiera parviflora mangroves. For mollusks, correlations were found between Terebralia palustris and Ellobium aurisjudae and the association of R. apiculata and B. parviflora mangroves. The highest crustacean Shannon-Wiener diversity index was associated with Sonneratia alba and Avicennia marina mangroves, and the highest mollusk Shannon-Wiener diversity index was associated with R. apiculata and B. gymnorrhiza mangroves.