Distribution of crabs along a habitat gradient on the Yellow Sea coast after Spartina alterniflora invasion

The effects of Spartina alterniflora invasion on macrobenthos have long been of concern; however, there is currently no unified conclusion regarding these effects. Most studies on crabs focus on one species or limited habitat types, and assessments of the community-level effects of S. alterniflora invasion considering multiple species and habitat types have rarely been conducted. In this study, we sampled crabs along a habitat gradient from the shoreline to inland areas on the Yellow Sea coast, including the mudflat, S. alterniflora marsh, Suaeda salsa marsh and Phragmites australis marsh. A total of 10 crab species were found among all habitats, with five species in the mudflat, six species in S. alterniflora marsh, seven species in S. salsa marsh and four species in P. australis marsh. The Shannon index values for the crab communities were similar between S. alterniflora marsh and S. salsa marsh, and these values were significantly higher than those for the mudflat and P. australis marsh. However, the total biomass of crabs was highest in the mudflat, and Metaplax longipes, Philyra pisum and Macrophthalmus dilatatus exclusively preferred the mudflat. The analysis of principal components and similarities showed that the crab community structure in S. alterniflora marsh was most similar to that in S. salsa marsh, while the crab community structure in the mudflat was most different from that in the other habitat types. Our results demonstrate that the distribution of crabs varies across a habitat gradient after S. alterniflora invasion and that the crab community in S. alterniflora marsh is slightly different from that associated with the local vegetation but shows a large difference from that in the mudflat. This study indicates that some crab species may have adapted to habitat containing alien S. alterniflora, while other crab species reject this new marsh type. The effects of the distribution of crabs after S. alterniflora invasion on the regional ecosystem need further study in the future

Habitat and bird composition in winter in Sanjiang Nature Reserve, China

Volume: 16Start Page: 163End Page: 16

Structure and Characteristics of Plant-Frugivore Network in an Urban Park: A Case Study in Nanjing Botanical Garden Mem. Sun Yat-Sen

Interaction between animals and plants is an important way to maintain terrestrial biodiversity and ecosystem function, but little is known about the structure of reciprocal networks between fruit plants and frugivore birds in urban habitats. To explore the characteristics of the plant–frugivore network and network roles of species, we observed the fruit ripening phenology of 21 species of fruit plants and the interactions between these plants and 39 species of frugivore birds during the whole year in a large urban park. Then, we assessed the characteristics of the total plant–frugivore and seasonal networks, and analyzed the network roles of species and the relationship between their network roles and ecological traits. Fruit ripened mainly in autumn and winter, and interaction connections in the two seasons contributed 39.68% and 44.83% to the total network, respectively. The specialization (H2′), connectance (C), nestedness, and interaction evenness (eH2) of the network were lower in autumn and winter, while the interaction diversity was higher. Compared with the networks (N = 1000) generated by the null model, the observed network exhibited higher nestedness and interaction diversity (E2) and lower specialization (H2′), connectance (C), and interaction evenness (eH2). A correlation analysis combining ecological traits and network roles showed that plants with black fruit had higher effective partners and partner diversity, while other traits of plants and birds were not significantly correlated with their network parameters. The important plants (N = 6) and birds (N = 3) contributed to 71.78% and 67.55% of the total network connection, they were mainly evergreen plants with black and red drupes and omnivorous generalist birds with medium and large sizes. Our research highlighted the seasonal differences in urban plant–frugivore network and the value of important species in maintaining network structures and providing ecosystem services

Anthropogenic Food Utilization and Seasonal Difference in Diet of Cercopithecus lowei at a Community Protected Forest in Ghana

In recent times, the diet and foraging behaviors of wild animals are influenced by anthropogenic foods since they often share their natural habitats with humans. We investigated the composition, preferred food item, contribution of anthropogenic food at garbage dump sites, and the seasonal effects on the diet of Lowe’s monkeys (Cercopithecus lowei) in the Duasidan Monkey Sanctuary, Ghana. We found that Lowe’s monkeys fed on 13 plant species, as well as anthropogenic foods and invertebrates. The composition of plant diet changed seasonally: Lowe’s monkeys relied more on buds in the dry season while they consumed more fruits in the wet season. However, anthropogenic food was a major component of the diet for both wet (34.8%) and dry seasons (41.3%), suggesting that the monkeys consistently rely on anthropogenic food throughout the year. Nevertheless, we did not observe any conflict between monkeys and local people. The results suggest that Lowe’s monkeys heavily rely on anthropogenic food at human garbage dumps while they maintain a part of their foraging activities in the wild, indicating a need for the proper management of garbage as well as the protection of the natural habitats of Lowe’s monkeys in the Duasidan Monkey Sanctuary, Ghana

Bulbuls and crows provide complementary seed dispersal for China’s endangered trees

Abstract Background Different functional frugivores generally exhibit unequal contributions, both in terms of quantity (seed removal) and quality (seedling recruitment), to effective seed dispersal of plant species. However, variations in this dispersal pattern generated by frugivores across different regions are still unknown. Methods In our study, we evaluated the contributions of two functional frugivore bird groups, the bulbuls (Pycnonotidae) and crows (Corvidae), in both the seed removal and seedling recruitment of the endangered Chinese yew tree (Taxus chinensis) across three different geographical regions in eastern China. Results The dominant crow species, Urocissa erythrorhyncha, was the most common disperser crow species at all sites, while the dominant bulbul species varied across the three sites. Furthermore, the two functional groups of dispersers diverged in the aspects of seed removal (quantity) and seedling recruitment pattern (quality). While bulbuls outperformed crows in seed removal (quantity), crows took more seeds to a safer site for seedlings (quality). Conclusions Our results highlight the importance of variations in the effective seed dispersal patterns of different functional disperser groups across different regions in the conservation and management of endangered tree species

Complete mitochondrial genome of the reed parrotbill Paradoxornis heudei (Aves: Passeriformes: Muscicapidae)

The mitochondrial genome of Paradoxornis heudei is described in this study. The molecule is 16,924 bp in length and contains 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and an AT-rich region. All PCGs use the typical start and stop codons, except COX3, ND2, and ND4 use T or TA as their stop codons. The rrnL and rrnS genes are 1602 bp and 984 bp in length, respectively. Phylogenetic analysis shows that the least evolved Paradoxornis locates at the basic position of Muscicapidae and among Paradoxornis, the other three species are firstly clustered together, then constitute a monophyletic group with P. heudei

A 4-MeO-TEMPO, PEG-NO2 and HCl Catalytic System for Highly Efficient Aerobic Oxidation of Alcohols

A combination of 4-MeO-TEMPO/PEG-NO2/HCl for catalytic aerobic oxidation of alcohol is described. A wide range of alcohols was efficiently oxidized to the corresponding carbonyl compounds by using this oxidation system and the turnover number (TON) for benzyl alcohol oxidation reached up to 56000

Effects of Invasive Smooth Cordgrass Degradation on Avian Species Diversity in the Dafeng Milu National Nature Reserve, a Ramsar Wetland on the Eastern Coast of China

Invasive smooth cordgrass (Spartina alterniflora) has been expanding rapidly through the coastal wetlands of eastern China and these changes negatively affect local birds. In the Dafeng Milu National Nature Reserve (henceforth referred to as DMNNR), rapid degradation of spartina occurs after an increase in milu (Elaphures davidianus; hereafter elk) numbers and ecological hydrological engineering. We evaluated the impact of such degradation on the abundance and species diversity of birds in the DMNNR during 2017–2021. We found that the area covered by S. alterniflora decreased significantly in the study area at a rate of 310 ha per year and by 62% during 2017–2021 (p S. alterniflora area, the species richness and abundance of birds first increased and then decreased. Songbird density clearly decreased but species richness did not significantly do so. This research demonstrated that during the initial stages of vegetation degradation, there was a positive effect on bird diversity. With the increasing vegetation degradation increases, both songbirds and waterbirds experience negative impacts. The DMNNR is an important stopover site for waterbirds in the East Asian–Australasian Flyway, and additional measures are needed to control vegetation degradation and to restore the native habitats for birds

Feeding Postures and Substrate Use of François’ Langurs (<i>Trachypithecus francoisi</i>) in the Limestone Forest of Southwest China

The feeding posture of a group of François’ langurs in Fusui County, Guangxi, was studied using instantaneous scan sampling from January to December 2016 to explore how the species adapts to karst limestone forests by collecting data on feeding posture, forest strata height, and substrate use. The results showed that leaves were the main food type of the François’ langurs, with young leaves accounting for 64.97% ± 19.08% of the food composition, mature leaves accounting for 11.88% ± 12.09%, fruits accounting for 12.96% ± 12.89%, flowers accounting for 4.16% ± 4.06%, and other food types, including stems, petioles, and other unknown parts of the tree, accounting for a total of 6.03% ± 9.09%. The François’ langurs had four main postures during feeding, of which sitting and bipedal standing feeding accounted for the largest proportions, at 85.99% ± 5.97% and 12.33% ± 6.08% of the total records, respectively. Quadrupedal standing and suspending were rarely observed and only appeared occasionally during feeding activities at the peak resting period, the two postures together accounting for 1.39% ± 1.59% of the total records. The feeding postures of the langurs had marked seasonal variation, as evidenced by the fact that seated feeding accounted for a significantly higher proportion of the total behavioral records in the rainy season than in the dry season, whereas feeding while standing bipedally was significantly more frequent during the dry season. Correlation analyses showed that feeding posture was correlated with food composition, showing a positive correlation between the proportion of bipedal standing feeding and mature leaf consumption. François’ langurs preferred to forage in the lower and middle forest layers, with the lower forest layer accounting for 55.93% ± 16.50% of the total number of recordings and the middle forest layer accounting for 33.63% ± 18.33%. Langurs were less likely to forage on the ground (rocks), accounting for only 6.79% ± 4.78% of the records. The frequency of langurs feeding in the upper part of the forest layer was the lowest at 3.65% ± 2.73%. Additionally, in the dry season, langurs utilized the lower forest layer more but used the middle forest layer less than in the rainy season. This study demonstrates that the spatial distribution of foods in the limestone forest has an important effect on the feeding posture of François’ langurs and their forest layer utilization

Cloning, Expression, and Characterization of a Novel Thermostable and Alkaline-stable Esterase from Stenotrophomonas maltophilia OUC_Est10 Catalytically Active in Organic Solvents

A thermostable and alkaline-stable novel esterase (Est7) was identified through the whole genome sequencing of Stenotrophomonas maltophilia OUC_Est10. The open reading frame of this gene encoded 617 amino acid residues. After heterologous expression in Escherichia coli BL21 (DE3), the purified Est7 was separated as a single protein and presented a molecular mass of 70.6 kDa. Multiple sequence alignment indicated that Est7 had a typical catalytic triad (Ser-Asp-His) and the conserved sequence (GDSL) typical of the family II lipid hydrolase proteins. Est7 showed good stability in alkaline buffers, especially in Tris-HCl buffer at pH 9.0 (residual activity 93.8% after 96 h at 4 &deg;C) and in the medium temperature conditions (residual activity 70.2% after 96 h at 45 &deg;C and pH 8.0). The enzyme also retained higher stability toward several hydrophilic and hydrophobic organic solvents (e.g., after incubation in 100% acetonitrile or in n-hexane the enzyme retained about 97% and 84% of the activity in the absence of organic solvent, respectively). Furthermore, Est7 could catalyze the transesterification reaction of vinylacetate with 2-phenylethanol and cis-3-hexen-1-ol to their corresponding acetate esters in petroleum ether or tert-butyl methyl ether. These results indicate Est7 as a promising biocatalyst for applications of Est7 in non-aqueous media