High Species Diversity Research Articles

Struktur Komunitas Karang Lunak Pada Kedalaman Berbeda di Teluk Jemeluk Amed, Kabupaten Karangasem, Bali

Reef is ecosystem in tropical waters which rich of biota constituent, with high species diversity. One of biota that compiler coral reefs are soft corals (Octocorallia, Alcyionacea). The aim of this research is to know the soft coral community structure at different depths and the influence of the limiting factors of soft corals. Soft coral data retrieval is done in 3 observation points. Each depth research carried out by installing 6 transects quadrants through 100 meter transect line parallel to the shoreline. Data retrieval of water quality carried out on site research and laboratory testing. The water quality data taken include; temperature, brightness, salinity, pH, flow velocity, DO, depth, nitrate and phosphate. Retrieving data using the soft coral community structure. The highest density values found in every station a depth of 5 meters and the lowest at each station a depth of 15 meters. According to Odum (1971), the value of diversity in the research area included in the high category of H' ? 3.0, as well as to the value of uniformity in the high category at stations 1 and 3 on each depth of H ? 0.6 and at station 2 for each depth in the low category of E ? 0.4. According to Odum (1971), the value of dominance classified in the high category of 0.75 to 1.00, which means that there are species that dominate that Sinularia flexibillis except at a depth of 15 meters which is rated as moderate dominance. The observation of the condition of the community structure is still relatively good, as the limiting factor in the study area is very suitable for soft corals.

Factors and thresholds determining sediment delivery pathways between forest road and stream in mountainous watershed

Road erosion is a global environmental issue. The transport of eroded sediment from road to stream can devastatingly impact water quality. Research efforts to combat this issue have prioritized maintaining roads and preventing erosion. Little research has explored the fate of eroded road materials in their transport from road to stream. Therefore, taking the Xiangchagou watershed in the Dabie Mountains of China as a case, this study investigated how local geography determines the formation and thresholds of different delivery pathways (gullied, partially gullied, and diffuse pathways) for road-eroded sediment through runoff, based on the binary logistic regression analysis, random forest model, and the lowest point data fitting methods. It explored how these different pathways have variable impacts on local plant and soil communities. Our results showed that soil D50, bulk density, shrub-grass coverage, and local plant diversity varied significantly (p < 0.05) between different delivery pathways. In particular, soil bulk density and local plant diversity varied significantly (p < 0.05) among different position of these delivery pathways. Specifically, the diffuse pathways are characterized by lower soil bulk density, looser soil structure, and higher species diversity, likely explained by the deposition of sediment-loaded runoff. Gullied pathways, conversely, had significantly more compacted surface soil and lower local plant diversity, likely as a result of scouring by sediment-loaded runoff. Slope gradient of upslope catchment (Us), road segment (Rs), and lower hillslope (Ds) and effective contributing area (Eca), which determine the intensity and kinetic energy of sediment-loaded runoff, are the main external drivers that determine the occurrence of gullied pathways. By contrast, the soil median particle size, surface roughness, and shrub-grass cover of lower hillslope, which contribute to erosion resistance of hillslope, are the primary intrinsic drivers promoting development of pathways from partial to full gully. Furthermore, we found that the critical topographic thresholds for the initiation of the gully pathways and the continued development of gully from partial to complete gully pathways could be expressed as Ds = 0.35Eca−0.13 and Ds = 0.41Eca−0.17, respectively. These results are expected to provide basis for understanding the formation and development mechanism of sediment delivery pathways from road to stream.

The Characteristics of the Skin Physiological Parameters and Facial Microbiome of "Ideal Skin" in Shanghai Women.

Everyone pursues perfect skin, but there exist significant differences between cultures, and no commonly accepted standards have been established. Therefore, our study attempted to define the "ideal skin" of oriental women and analyze the relationship between different skin physiological parameters and microbiomes. Based on our customized grading standard, the VISIA CR photos of 111 young women aged from 18 to 25 in Shanghai were collected and scored by the severity of pores, acne, spots, and wrinkles. The volunteers were then divided into "ideal skin" (W1), "normal skin" (W2), and "undesirable skin" (W3) groups. The physiological parameters of facial skin were measured by non-invasive instrumental methods, and the skin microbiome was analyzed by 16S rRNA and ITS high-throughput sequencing. From "ideal skin" to "undesirable skin", the skin physiological parameters, α-diversity, and composition of the facial microbiome showed noticeable regular changes. Compared with the "normal skin" (W2) and "undesirable skin" (W3), the "ideal skin" (W1) group had lower sebum content, TEWL, melanin, hemoglobin, and roughness but higher hydration content and skin pH value. Furthermore, the Shannon index of skin bacteria was significantly increased in W1 (P = 0.004), suggesting that the ideal skin had higher species diversity. From W1 to W3, the species composition was changed significantly. The abundance of Actinobacteria was increased, while Proteobacteria and Bacteroidetes were decreased. Correspondingly, the abundances of lipophilic Propionibacterium and Malassezia were increased, while the abundances of Stenotrophomonas, Pseudomonas, Ralstonia, and Streptococcus, were significantly decreased. Additionally, Spearman correlation analysis revealed strong correlations between the physiological parameters and the microbiota. Notably, the Shannon index of skin bacteria was significantly positively correlated with skin hydration (P = 0.03) but negatively correlated with the abundance of Cutibacterium (P = 0.000), hemoglobin content (P = 0.025), and sebum content (P = 0.5). Therefore, the skin hydration content and the abundance of Cutibacterium played an important role in maintaining the α-diversity and skin homeostasis. Ideal skin had better water-oil balance and barrier function, higher microbial diversity, and more reasonable species distribution. Therefore, daily skincare needs to control skin oil and maintain skin microecological balance to achieve ideal skin conditions for young women aged 18-25 years old.

Overview of the Success of In Vitro Culture for Ex Situ Conservation and Sustainable Utilization of Endemic and Subendemic Native Plants of Romania

Romania has a relatively high diversity of plant species, including 3829 vascular and 979 non-vascular spontaneous plant taxa (species and subspecies). Due to uncontrolled harvesting as well as other causes, including climate change and ecological collapse, the speed of species extinction and the narrowing of the genetic base of plant resources has been reported as a critical issue. Therefore, the national Red List of Romanian flora includes 1453 threatened taxa, of which 95 are endemic and 90 subendemic. Many of these have high ornamental, medicinal–cosmetic, and/or aromatic properties. The high extinction risk of these valuable plants has stimulated both the reconsideration of their vital importance as genetic resources and interest in finding effective methods for conservation. Cultivating these phytogenetic resources in a human-controlled environment is of high importance for effective ex situ conservation, which can further serve sustainable exploitation needs and may facilitate in situ conservation actions. In vitro culture is a powerful tool for producing elite plants for cultivation for different purposes. This review summarizes the current knowledge on in vitro multiplication of 22 endemic and subendemic native plants of Romania, examining the materials used, the treatments applied, and the results obtained in each stage of the micropropagation protocol (culture initiation, proliferation, rooting, and acclimatization). The findings from the reviewed studies are presented in a comparative way, and the potential of plant tissue culture in conservation and sustainable exploitation of these Romanian species is outlined.

Phylogenetic analyses reveal bat communities in Northwestern Mexico harbor a high diversity of novel cryptic ectoparasite species.

Parasites are integral parts of ecosystem function and important drivers of evolutionary processes. Characterizing ectoparasite diversity is fundamental to studies of host-parasite interactions, evolution, and conservation, and also for understanding emerging disease threats for some vector borne pathogens. With more than 1400 species, bats represent the second most speciose mammalian clade, but their ectoparasite fauna are poorly known for most species. We sequenced mitochondrial Cytochrome Oxidase C subunit I and nuclear 18S ribosomal gene fragments, and used Bayesian phylogenetic analyses to characterize ectoparasite taxon identity and diversity for 17 species of parasitized bats sampled along the Baja California peninsula and in Northwestern Mexico. The sequence data revealed multiple novel lineages of bat bugs (Cimicidae), flies (Nycteribiidae and Streblidae), and ticks (Argasidae). Within families, the new linages showed more than 10% sequence divergence, which is consistent with separation at least at the species level. Both families of bat flies showed host specificity, particularly on Myotis species. We also identified new records for the Baja peninsula of one tick (Carios kelleyi), and of five Streblid bat fly species. One Nycteribiid bat fly haplotype from Pallid bat (Antrozous pallidus) hosts was found throughout the peninsula, suggesting potential long distance co-dispersal with hosts. Different bat bug and tick communities were found in the north and south of the peninsula. This study is the first systematic survey of bat ectoparasites in the Baja California peninsula, revealing novel lineages that are highly genetically differentiated from other parts of North America. For some ectoparasite species, haplotype distributions may reflect patterns of bat migration. This work is a first step in characterizing ectoparasite diversity over the Baja California peninsula, and understanding how ecological and evolutionary interactions shape bat ectoparasite communities among host species in different parts of their ranges.

Diversity and enzymatic activity of the microbiota isolated from compost based on restaurant waste and yard trimmings

IntroductionThe bad management of organic waste negatively affects environmental quality and composting has been a viable recycling alternative. Microorganisms are responsible for waste degradation during the composting process and, consequently, for transforming this waste into natural fertilizer. This work aimed to analyze and identify the biodiversity of yeasts and filamentous fungi throughout a composting process based on organic residues under different treatments (commercial inoculum, non-commercial inoculum, and control treatment) and to investigate the enzymatic activity of these microorganisms.MethodsMicroorganisms were isolated and identified from samples at 0, 5, 10, 20, 40, 60, and 120 days. Filamentous fungi were identified according to their macroscopic and microscopic characteristics, and yeasts were identified by sequencing the 18S rDNA region. All identified strains were evaluated for ligninolytic, cellulolytic, hemicellulolytic, amylolytic, pectinolytic, proteolytic, lipolytic, and ammonification. During the composting phases, the filamentous fungi were higher than the yeast population.Results and discussionAt the beginning of the process, a higher species diversity was observed, and the population of yeasts and filamentous fungi was, on average, 6.50 log CFU g−1. The microbial communities were similar throughout the process in the two inoculated treatments, which showed more significant microbial activity, diversity, and efficiency in the transformation of organic matter, and consequently, advantages in terms of the final product quality compared to the control treatment. The yeasts Pichia kudriavzevii, Pichia farinosa, Issatchenkia orientalis, and the filamentous fungi of the genus Aspergillus spp. proved to have high biotechnological value and could be used as starter cultures to accelerate the composting process.

Two new deep-water species of squat lobsters (Crustacea: Anomura: Galatheoidea) from the Central and Southwest Indian Ridge

The high diversity and endemism of benthic species on seamounts are extensively documented. Although the number of squat lobster species from seamount habitats has increased, species from the Central Indian Ridge (CIR) and Southwest Indian Ridge (SWIR) systems remain largely unknown. The hydrothermally active Indian Ridge system harbours potential sites for future Seafloor Massive Sulphides (SMS) mining. Since seabed mining may create a long-lasting impact on the deep-sea ecosystems, it could harm the unique deep-sea life associated with mineral deposits. This study identified two undescribed squat lobster specimens: one from the genus Munidopsis Whiteaves, 1874 from the CIR system in water depths ranging from 1981 to 2033 m, and one from the genus Typhlonida Macpherson & Baba in Machordom, Ahyong, Andreakis, Baba, Buckley, Garcia-Jimenez, McCallum, Rodriguez-Flores & Macpherson, 2022 from the SWIR system in depths ranging from 2070 to 2404 m. Both new species may be distinguished morphologically and genetically based on the partial mitochondrial (mtCOI) gene. To generate baseline environmental and biodiversity data, efforts for accurate sampling and correct identification of biological species are required.

Infestation of Oriental House Rat (Rattus tanezumi) with Chigger Mites Varies along Environmental Gradients across Five Provincial Regions of Southwest China.

Chigger mites are the exclusive vector of scrub typhus. Based on field investigations of 91 survey sites in 5 provincial regions of Southwest China, this paper reported variations of chigger infestation on the oriental house rat (Rattus tanezumi) along various environmental gradients. A total of 149 chigger species were identified from 2919 R. tanezumi in the 5 provincial regions, and Leptotrombidium deliense (a major vector of scrub typhus in China) was the first dominant chigger species, followed by Ascoschoengastia indica and Walchia ewingi. Rattus tanezumi had a stable overall prevalence (PM = 21.10%), mean abundance (MA = 7.01), and mean intensity (MI = 33.20) of chiggers with the same dominant mites in the whole Southwest China in comparison with a previous report in Yunnan Province, but chigger infestations on R. tanezumi varied along different environmental gradients. Rattus tanezumi in mountainous landscape had a higher infestation load of chiggers with higher species diversity than in flatland landscape. The infestation was higher at lower altitudes and latitudes. A high intensity of vegetation coverage was associated with high infestations. The results reflect the environmental heterogeneity of chiggers on the same host species. Warm climate and high relative humidity are beneficial to chigger infestation on R. tanezumi.

Diversity, Composition, and Abundance of Avian Species in and around SemienMecha District Wetlands North Western, Ethiopia

The objective of the present study was assessing the species composition, relative abundance and species diversity of avifauna found in wetlands of Semin Mecha District. The diversity, relative abundance and distribution of the avian species were investigated from January 2019 to August 2019 both wet and dry seasons. Both point count and line transect methods were employed to identify birds from the three wetlands. A total of 39 species, 28 genera 14 families and 8 orders were identified. The order Charadriiformes dominated the list (4 families with 14 species) followed by Pelecaniformes (2 families with 9 species), Gruiformes (2 families with 4 species), suliformes 2 families with 3 species), psseriformes (1 family with 6 species), the rest Accipitriformes, phoenicopteriformes and podicipediformes(1 family with 1 species) each. Out of total 39 species, one species (Black billed gull) was endangered, two species (wattled crane and Black crowned crane were vulnerable, one specie (Rouget's rail) was near threatened, and thirty five bird species recorded were under the Least Concern category. Species abundance and diversity varied between the three habitats. Weinner Simpson index showed significant diversity of birds in Koga reservoir had higher species diversity (H’=5.9) followed by kurt Bahir dembar(H’=4.15) and lower species diversity Kurt Bahir (H’=2.53).The study shows that habitat destruction due to anthropogenic activities:- over-grazing, sedimentation, poor management of catchment, recession farming, over-utilization of resources, lack of awareness , Lack of sense of ownership, giving less attention to conservation were the main threats to the survival of wetland birds in the study area. The current management of wetlands is poor because of misuse of wetlands as the result birds are endangered. Thus urgent conservation measures are recommended to conserve the bird species.

Seasonal difference in soil health indicators mediating multidiversity-multifunctionality relationship depends on body size of soil organisms: Evidence from rubber plantation agroforestry system

Soil health is the foundation for the maintenance of ecosystem stability and multifunctionality. It is necessary to identify the key indicators of soil health that indicate ecosystem multifunctionality against anthropogenic disturbances such as land use change. Many studies have shown the pivotal role of soil biodiversity in maintaining ecosystem multifunctionality. However, the key role of soil multidiversity (including different body size soil organisms across multitrophic levels) in affecting ecosystem functions is poorly understood. We have implemented a multitrophic perspective to study soil multidiversity by including bacteria, fungi, nematodes (5 feeding types), and arthropods (thripidae, poduridae, and others). Here we show that a multitrophic approach for soil biodiversity assessment is important to highlight trophic interactions and their subsequent effects on the soil multidiversity-ecosystem multifunctionality (MEF) relationship. We postulate that soil multidiversity promotes soil health and thus drives the MEF relationship. We assessed soil multidiversity, 11 variables for ecosystem functions, and ecological network stability (reflected by co-occurrence network patterns) in rubber plantations differing in land-use intensity represented by monoculture (MRP), high (RHD) and low (RLD) diversity of other plant species. We also included tropical rainforest (TRF) as a reference system to compare our results. Results showed that soil multidiversity, multifunctionality, and soil network stability significantly improved in RHD as compared to MRP. Soil multidiversity rather than single diversity component had strong positive effects on multifunctionality. More specifically, we found that the relationship between soil multidiversity and multifunctionality was seasonally dependent on the soil attributes and the body size of soil organisms. We observed a negative correlation between large body size organisms and soil nutrients content in the dry season while a positive correlation between small body size soil organisms and enzymatic activities in the rain season. Particularly, we emphasized the role of soil multidiversity in enhancing ecosystem multifunctionality and stability via its prominent impacts on soil health. Our study elucidates that accurate identification of soil health indicators is an important approach to imply remedial management strategies to maintain soil health and MEF relationship in managed ecosystems such as rubber plantations.

Factors influencing carrion communities are only partially consistent with those of deadwood necromass

Research on decomposer communities has traditionally focused on plant litter or deadwood. Even though carrion forms highly nutrient-rich necromass that enhance ecosystem heterogeneity, the factors influencing saprophytic communities remain largely unknown. For deadwood, experiments have shown that different drivers determine beetles (i.e., decay stage, microclimate, and space), fungi (i.e., decay stage and tree species) and bacteria (decay stage only) assemblages. To test the hypothesis that similar factors also structure carrion communities, we sampled 29 carcasses exposed for 30 days that included Cervus elaphus (N = 6), Capreolus capreolus (N = 18), and Vulpes vulpes (N = 5) in a mountain forest throughout decomposition. Beetles were collected with pitfall traps, while microbial communities were characterized using amplicon sequencing. Assemblages were determined with a focus from rare to dominant species using Hill numbers. With increasing focus on dominant species, the relative importance of carcass identity on beetles and space on bacteria increased, while only succession and microclimate remained relevant for fungi. For beetle and bacteria with focus on dominant species, host identity was more important than microclimate, which is in marked contrast to deadwood. We conclude that factors influencing carrion saprophytic assemblages show some consistency, but also differences from those of deadwood assemblages, suggesting that short-lived carrion and long-lasting deadwood both provide a resource pulse with different adaptions in insects and microbes. As with deadwood, a high diversity of carcass species under multiple decay stages and different microclimates support a diverse decomposer community.

Marine traffic and potential impacts towards cetaceans within the Madeira EEZ

Human population growth has resulted in an increase of marine traffic. This has been associated with wildlife disturbance and the effects are expected to increase with continued traffic expansion. A particularly impacted group is cetaceans, known to play an important role in the sustainability and regulation of marine ecosystems. An assessment of marine traffic can therefore contribute towards wildlife conservation measures, especially when evaluated in the context of important areas for cetaceans. The present study took place in Madeira’s Exclusive Economic Zone (EEZ), an area hosting a high diversity of cetacean species as well as island-associated groups. Automatic Identification System (AIS) data were collected from a land station between 2008 and 2011 and marine traffic and cetacean visual data collected during shipboard surveys between 2001 and 2011. Results show that Madeira’s offshore traffic (up to 12 n.miles from the shore) corresponds to approximately 12% and 22% of the traffic observed in the Baltic and North Sea, respectively. It is mostly composed of cargo ships navigating over fixed routes and using the area as a passage towards different destinations. Cruise ships intersect the area mainly to reach Funchal’s port. The number of recreational boats in the area was found to be underestimated since many of them are not equipped with AIS devices. The level of Madeira inshore traffic is harder to evaluate since it is a small area encompassing a shipping route, yet it may represent 0.8% of the traffic recorded in the Strait of Gibraltar. According to the inshore shipboard survey data, coastal marine traffic is mainly composed of fishing boats (47%), recreational boats (24%), ships (17%), whalewatching boats (10%) and big game fishing boats (2%). Most inshore and offshore vessels were found to be navigating at over 10 knots. An inshore ‘higher use corridor’ common to both vessels and cetaceans was identified as a potential danger zone.

Gapless Genome Assembly of Puccinia triticina Provides Insights into Chromosome Evolution in Pucciniales.

Chromosome evolution drives species evolution, speciation, and adaptive radiation. Accurate genome assembly is crucial to understanding chromosome evolution of species, such as dikaryotic fungi. Rust fungi (Pucciniales) in dikaryons represent the largest group of plant pathogens, but the evolutionary process of adaptive radiation in Pucciniales remains poorly understood. Here, we report a gapless genome for the wheat leaf rust fungus Puccinia triticina determined using PacBio high-fidelity (HiFi) sequencing. This gapless assembly contains two sets of chromosomes, showing that one contig represents one chromosome. Comparisons of homologous chromosomes between the phased haplotypes revealed that highly frequent small-scale sequence divergence shapes haplotypic variation. Genome analyses of Puccinia triticina along with other rusts revealed that recent transposable element bursts and extensive segmental gene duplications synergistically highlight the evolution of chromosome structures. Comparative analysis of chromosomes indicated that frequent chromosomal rearrangements may act as a major contributor to rapid radiation of Pucciniales. This study presents the first gapless, phased assembly for a dikaryotic rust fungus and provides insights into adaptive evolution and species radiation in Pucciniales. IMPORTANCE Rust fungi (Pucciniales) are the largest group of plant pathogens. Adaptive radiation is a predominant feature in Pucciniales evolution. Chromosome evolution plays an important role in adaptive evolution. Accurate chromosome-scale assembly is required to understand the role of chromosome evolution in Pucciniales. We took advantage of HiFi sequencing to construct a gapless, phased genome for Puccinia triticina. Further analyses revealed that the evolution of chromosome structures in rust lineage is shaped by the combination of transposable element bursts and segmental gene duplications. Chromosome comparisons of Puccinia triticina and other rusts suggested that frequent chromosomal arrangements may make remarkable contributions to high species diversity of rust fungi. Our results present the first gapless genome for Pucciniales and shed light on the feature of chromosome evolution in Pucciniales.

Orthoptera (Insecta) fauna of the Kashkadarya region, Uzbekistan

Abstract. Nurjaniv AA, Medetof MZH, Kholmatov BR, Abdullahyev II, Tufliyev NKH, Nurjonov FA. 2023. Orthoptera (Insecta) fauna of the Kashkadarya region, Uzbekistan. Biodiversitas 24: 112-121. More than 30,000 different species of orthoptera insects, most of which are found in the tropics and subtropics, are known to exist in the world's fauna. The most extensive among the orthopteroids is the order Orthoptera, which includes more than 20,000 species of insects. Most are herbivores, while others are predators or have a mixed diet. Large size, jumping abilities, and open lifestyle make orthopteran characters accessible to many landscapes. Orthopterans play a significant role in the movement of the energy flow as an important link in biocenosis, connecting secondary consumers with producers. Many species of Orthopterans, especially grasshoppers, are dangerous pests of agriculture. Harm is especially noticeable from those locust species, which could make swarms. The research was carried out in various agro and natural landscapes to determine the species composition of orthopteran insects in the Kashkadarya region. A total of 1274 samples were collected from 11 coordinates in 10 different landscapes during the scientific trips. They comprised 657 females (51.4%), 403 males (31.6%), and 214 nymphs (16.7%). The distribution of 70 species belonging to 50 genera and 7 families of orthopteran insects is discussed in this research. Samples were taken from 6 coordinates in 6 types (cucurbits, orchards, alfalfa, mulberry, vineyards, and mung bean fields) of agro-landscapes and 6 coordinates in 4 natural (plains of the Karshi desert, hills, mountains, and saxaul forests) landscapes. The highest species diversity has been found in orchards, where 129 samples of 20 orthopteran species have been collected in the Guzar district of the Kashkadarya region. The Karshi desert was identified as the landscape with the lowest number of species, with 41 samples of 9 species collected. The average density of insects in the desert was 0.4 per square meter. Two species were found in all 12 coordinates of 10 different landscapes, and 11 were found only once in one coordinate.

Microfaunal Recording of Recent Environmental Changes in the Herschel Basin, Western Arctic Ocean

ABSTRACTMicrofaunal assemblages of benthic foraminifera, ostracods, and tintinnids from two marine sediment cores retrieved from the Herschel Basin of the Canadian Beaufort Sea shelf document relationships with environmental parameters such as salinity, sea-ice cover, and turbulence. Cores YC18-HB-GC01 and PG2303-1 were collected at 18 and 32 m water depth, respectively. At these sites, sediment accumulation rates range between 0.6 and 1.7 cm yr–1 allowing a near-annual temporal resolution over the last 50 years. Multivariate analyses indicate that benthic foraminiferal assemblages respond primarily to food supply. Dissimilarities between the microfaunal assemblages of the two cores are mainly the result of bottom water salinity levels linked to water depth. High abundance of the benthic foraminiferal species Elphidium clavatum and occurrences of Elphidium bartletti point to varying, but relatively low, salinities at the shallow core site YC18-HB-GC01, which may be affected by variations in the summer halocline depth. Higher species diversity and more abundant Cassidulina reniforme and Stainforthia feylingi characterize the deeper core PG2303-1, which might reflect more stable conditions and higher bottom-water salinities throughout the studied time interval. The most important microfaunal shift of the last 50 years, observed in the shallower longer core YC18-HB-GC01, occurred at the turn of the 21st century. Prior to ∼2000 CE, the presence of Islandiella norcrossi indicates more stable and saline conditions. Since ∼2000 CE, increased abundances of Haynesina nivea and of the ciliate Tintinnopsis fimbriata suggest decreased salinity and increased turbidity. An increased abundance of Eoeponidella pulchella after ∼2000 CE suggests a concurrent increase in productivity in the last two decades. This shift is nearly synchronous with a decrease in mean summer sea-ice concentration, which can play an important role in bottom water stability on the shelf. Easterly winds can induce a reduction in the sea-ice cover, but also foster a westward spreading of the Mackenzie River plume and the upwelling of nutrient-rich Pacific waters onto the shelf. Both factors would explain the increased freshening and productivity of the Herschel Basin. The last two decades were also marked by a decrease in ostracod abundance that may relate to higher water turbidity. This study shows that combining information from benthic foraminifera, ostracods, and tintinnids provides a comprehensive insight into recent hydrographic/climatic changes in nearshore Arctic habitats, where productivity is critical for the food security of local communities.

Plants diversity and socioecological functions of homegarden in Sundanese rural area: A case in Sumedang District, West Java, Indonesia

Abstract. Suwartapradja OS, Iskandar J, Iskandar BS, Mulyanto D, Suroso, Nurjaman D, Nisyapuri FF. 2023. Plants diversity and socioecological functions of homegarden in Sundanese rural area: a case in Sumedang district, West Java, Indonesia. Biodiversitas 24: 156-175. Homegarden is one of the traditional agroforestry systems in Indonesia, which is traditionally planted with various annual and perennial plants. It has provided social, economic, cultural, and ecological functions. The objective of this study is to elucidate the vegetation structure and function of the homegarden system of two groups of rural communities who are affected by the development project of Jatigede Dam, Sumedang, West Java. The first community group of residents who lost their village, their homegarden, and another agricultural land due to the Jatigede dam and settled in new resettlement provided by the local government in Cihegar Mekar Hamlet. The second community group, residents living in the neighboring Kampung Cihegar Mekar, whose settlements and homegarden were not inundated by the Jatigede Dam, but the Jatigede Dam inundated their agricultural lands. Qualitative and quantitative methods were used with an ethnobotanical approach. The results showed that the diversity of species of the homegarden of Cihegar Mekar and Ciboboko Hamlets affected by the Jatigede dam project was high. In Cihegar Hamlet, the number of species, genera, and family in 2018 and 2022 was recorded at 63 and 155, 58 and 130, and 39 and 59, respectively. While in Ciboboko, Hamlet in 2018 and 2022 recorded the number of species, genera, and family at 81 and 144, 76 and 114, and 44 and 55, respectively. These variables have significantly increased in the past 4 years (2018-2022). The residents are intensifying the cultivation of their homegarden because other agricultural land types, such as wet-rice fields, have been dramatically reduced or even lost due to inundation by the Jatigede dam. The 224 plant species found in the homegarden consist of 127 (56.70%), 30 (13.39%), 27 (12.05%), and 13 (5.80%) ornamental, fruit, vegetable, and spice species. At least 20 species and varieties (landraces) of the homegarden have been considered to fulfill the daily household need, and some surpluses are sold to obtain household income. So, the high diversity of plant species in the village homegarden has essential functions to support food security and the population well-being of those affected people of the development project of Jatigede Dam. Homegardens appear to be an important strategy for attaining the rural development program and can be accomplished with proper planning.

Growth and drought resilience of four native tree species suitable for reforestation of Brazil’s Atlantic Forest

Abstract Deforestation of tropical forests has been a critical issue affecting climate change mitigation and biodiversity conservation. Reforestation strives to remedy this situation, yet it is futile as long as deforestation of primary forests continues. Since deforestation is partly motivated by the demand for valuable tropical wood, reforestation should focus not only on planting native tree species, but specifically on a high diversity of native tree species with high-quality wood. However, the eco-physiological information required for growing such species is limited, and their resilience to drought events is unknown. Here, we focused on four native tropical wood tree species identified as suitable for Brazil’s Atlantic Forest reforestation. Growth, carbon assimilation, water-use and xylem hydraulics were studied in seedlings of the two legume species Dalbergia nigra and Plathymenia foliolosa and the two non-legume species Cariniana legalis and Zeyheria tuberculosa. Seedlings were monitored weekly for 9 consecutive weeks, three to five weeks of which under induced drought. Growth and carbon assimilation were 25–65 per cent higher in the legume vs. non-legume species. In turn, non-legume species mostly avoided the drought by stomatal closure, producing a 50 per cent higher water-use efficiency (WUE) compared with the legume species. The average water potential at 50 per cent stomatal conductivity (Ψgs50) for legume species was −2.6 MPa, whereas for non-legume species it was −0.85 MPa. Still, each species showed a unique set of responses, indicating different growth strategies under mesic and xeric conditions. Our results indicate a divergence among legume and non-legume species, driven by a trade-off between plant productivity (carbon assimilation and growth) and plant safety (stomatal regulation and WUE). All in all, the four species of juvenile potted plants demonstrated a high capacity for recovery from drought, which supports their potential role in future reforestation under climate change.

Venom comparisons of endemic and micro-endemic speckled rattlesnakes Crotalus mitchellii, C. polisi and C. thalassoporus from Baja California Peninsula

A high diversity of rattlesnake species can be found in the Baja California peninsula and the island of the Gulf of California, nevertheless, their venom has been poorly evaluated. The aim of this work was to present the first characterization of endemic Crotalus mitchellii, micro endemic C. polisi and C. thalassoporus venoms. All samples provoke human plasma coagulation showing doses in the rank of 2.3–41.0 μg and also produce rapid hydrolysis of the alpha chain of bovine fibrinogen while the beta chain is attacked at larger incubation periods by C. polisi and especially by C. thalassoporus. Phospholipase activity ranging from 23.2 to 173.8 U/mg. The venoms of C. thalassoporus and C. polisi show very high hemorrhagic activity (from 0.03 to 0.31 μg). A total of 130 toxin-related proteins were identified and classified into ten families. Crotalus mitchellii venom was characterized by high abundance of crotoxin-like and other phospholipase proteins (34.5%) and serine proteinases (29.8%). Crotalus polisi showed a similar proportion of metalloproteinases (34%) and serine proteinases (22.8%) components with important contribution of C-type lectins (14.3%) and CRiSP (14.0%) proteins. Venom of C. thalassoporus is dominated by metalloproteases that amount to more than 66% of total toxin proteins. These results provide a foundation for comprehending the biological, ecological and evolutionary significance of venom composition of speckled rattlesnake from the Baja California peninsula.

The vegetation cover dynamics and potential drivers of habitat change over 30 years in the Free State National Botanical Garden, South Africa

As a conservation strategy, the South African National Biodiversity Institute (SANBI) establishes biodiversity gardens in areas with unique vegetation types that are vulnerable to extinction. The study aimed to (1) determine the vegetation cover dynamics of the Free State National Botanical Garden (FSNBG) over a 30-year period (1987–2017), focusing on different vegetation classes; (2) evaluate the ecological integrity of the Critical Biodiversity Area 1 (CBA1) vegetation using species abundance and vegetation cover; and (3) quantify potential conservation threats that may be drivers of vegetation cover changes. The “moderate vegetation cover” and “dense vegetation cover” had increased by 25.1 ha and 8.6 ha respectively in the FSNBG. Woody vegetation cover expanded significantly over the past 30-year period, suggesting “bush” encroachment. Shannon–Wiener diversity indices showed high overall plant species diversity of CBA1 vegetation type (H = 3.5), with the vegetation cover remaining high (79.6 ± 15.9%), 50 plant species no longer existing, suggesting reduced taxonomic richness. Major conservation threats included the presence of 27 alien and invasive plant species interspersed within different vegetation patches and anthropogenic habitat fragmentation in the past 19 years (i.e. covering ~ 18% of the buffer zone). We conclude that increased vegetation cover is associated with bush encroachment and we recommend interventions to reduce the population density of woody plants and establish permanent vegetation monitoring plots.

Eels as natural samplers highlight spatial heterogeneity in energy flow in an estuary

The high spatiotemporal heterogeneity makes it difficult to ensure the representation of samples in estuarine studies. Using Japanese eels as natural samplers (n = 881), we revealed the spatial heterogeneity of energy flow among three successive estuarine segments (upper, middle, and lower estuaries) of the Hamana Lake−Miyakoda River system on the Pacific side of central Honshu, Japan. In the upper estuary which serves as the nursery ground for eels, the predominant small eels (body weight <30 g) fed mainly on polychaetes (58.8% IRI [index of relative importance]), mainly Hediste atoka. This polychaete species depends on the detritus food chain driven by terrestrial inputs, and the detritus food chain appears to be predominant in the upper estuary. However, large eels (body weight >150 g) fed directly on terrestrial subsidies in the form of fallen insects (49.0% IRI) and earthworms (20.2% IRI), indicating that the detritus food chain does not directly affect the diet of large eels. Terrestrial subsidies in the form of living organisms do not contribute to the diet of eels in the adjacent middle estuary, which is the main growth habitat for eels within an estuary. However, small eels depend on terrestrial subsidies by feeding on oysters (71.6% IRI), which assimilate terrestrial particulate organic matter. The predominant medium eels were highly dependent on the high diversity and biomass of prey groups, as indicated by the high % IRI values of several groups, such as infaunal bivalves (31.7% IRI), oysters (19.0% IRI), amphipods (22.6% IRI), and polychaetes (16.4% IRI). Eelgrass beds usually serve as shelters and foraging areas for medium and large eels in the lower estuary. Despite the high species diversity around seagrass meadows, the eels concentrated on infaunal bivalves (85.4% IRI) with high biomass, predominantly Anadara sp. In addition to being tools for monitoring fauna, eels as natural samplers provide insights into the energy flow in ecosystems.